4.6 cast iron tensioner mod

GambleS197

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Getting ready to change the timing set on my car with a mmr kit before my first event for the year after talking with a buddy who built his motor he told me to file the teeth off the the tensioners. After reading a few other post seen a few guys talking about adding plunger spacers as well when doing them. My question is is the spacer necessary or can I get away with just filling the last three or four teeth can’t really find a definite answer anywhere
 

lwarrior1016

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There is a lot of debate on this topic. Personally, I like the spacer better. The whole point is to keep the chain tight in the event oil pressure is low. Or even during cranking, when you have no oil pressure.
 

GlassTop09

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After reading a few other post seen a few guys talking about adding plunger spacers as well when doing them.
Personally, I like the spacer better. The whole point is to keep the chain tight in the event oil pressure is low. Or even during cranking, when you have no oil pressure.
Just did a search on this after reading y'all's postings.................damn, I also like the spacer remedy as well (didn't know this was a thing)........so much so I'm gonna get me a set of them to put under the plungers inside of my OEM Ford cast iron chain tensioners then grind off the last 3-4 teeth of the ratchet stands because w\ these spacers installed under the plungers, the ratchets operating, IMHO, is now a moot point. These spacers should make this a very bulletproof setup going forward.

Glad I procrastinated on starting\doing my timing refresh job 1 more time...........would've missed out on this.

OP, I also agree w\ lwarrior1016.............go w\ the spacers.

 

lwarrior1016

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Just did a search on this after reading y'all's postings.................damn, I also like the spacer remedy as well (didn't know this was a thing)........so much so I'm gonna get me a set of them to put under the plungers inside of my OEM Ford cast iron chain tensioners then grind off the last 3-4 teeth of the ratchet stands because w\ these spacers installed under the plungers, the ratchets operating, IMHO, is now a moot point. These spacers should make this a very bulletproof setup going forward.

Glad I procrastinated on starting\doing my timing refresh job 1 more time...........would've missed out on this.

OP, I also agree w\ lwarrior1016.............go w\ the spacers.

I had a machinist buddy that cut a new set of plungers for me one time. They were longer than stock, so no spacers. And I just completely removed the ratchet piece out of it.

Nowadays, I’ve just been running the stock iron tensioners with the ratchet setup untouched.
 

GlassTop09

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I had a machinist buddy that cut a new set of plungers for me one time. They were longer than stock, so no spacers. And I just completely removed the ratchet piece out of it.

Nowadays, I’ve just been running the stock iron tensioners with the ratchet setup untouched.
Ah, so you've already done some reengineering of this design I see.........good stuff!

I was gonna do exactly the same w\ my iron tensioners (use the ratchets untouched) until I saw this thread & noted that someone had made a spacer to do w\ the existing plungers what you've already done prior.

I've always thought that this issue was best controlled thru limiting the plunger compression stroke length (looking at a 3rd Gen Coyote\VooDoo chain tensioner it looked like Ford had done this w\ the plunger design in these thus the ratchet was no longer needed\used) but never thought that the old Ford 2V cast iron chain tensioner plungers could be modified to actually adjust this plunger compression stroke length..........now I know better as someone figured out a simple method of doing this..........which makes these OEM Ford 2V cast iron chain tensioners the far & away best replacement part to use w\ a 4.6L\5.4L 3V as these solve so many of the known issues w\ the plastic units w\o any downside.......IMHO, whether the ratchets are used untouched or modified in conjunction w\ the spacers added under the plungers.

The deciding factor in my mind which way to go is whether or not a 2-step\NM2B WOT box (so specifically drag racing centered......) is being used..........or in my case, I only want to go thru this work 1 time thus I'm looking at\for the best overall design setup to go with for longevity along w\ retaining cam timing accuracy while eliminating as many of the known deficiencies around the plastic units thus I'm now favoring the OEM Ford 2V cast iron tensioners w\ modified ratchets & plunger spacers limiting the plunger compression stroke length over untouched ratchets now that I've been made aware of these plunger spacers & the reasoning for their use.............maybe a little over engineered if no 2-step\WOT box is used but definitely just as effective.......also is permanent once done........which is what appeals to me.
 

JC SSP

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Anyone have a pic of these plunger extensions or the filing of rachet teeth?
 

GlassTop09

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I had a machinist buddy that cut a new set of plungers for me one time. They were longer than stock, so no spacers. And I just completely removed the ratchet piece out of it.

Nowadays, I’ve just been running the stock iron tensioners with the ratchet setup untouched.
Hey lwarrior1016,

I got my set of 4.6L\5.4L cast iron tensioner plunger spacers in last week & pulled out my set of cast iron tensioners to see how these install..........what I saw when I pulled the plungers out of the tensioner bodies has answered a LOT of other questions I had surrounding these.......like why the "extra" chain oiling orifice in the tensioner body for 1..........that is not present on any Ford 3V Modular plastic chain tensioner.

Now I figured out\know exactly how Ford had initially designed these cast iron tensioners to operate & now even more, I understand that Ford knew they were making a substandard chain tensioner when they designed\used the plastic units for the production line 4.6L\5.4L 3V Modulars & why the 2V Modulars ran so long w\o timing & guide issues.....until folks started using 2-steps\NM2B WOT boxes or tuners sidestepping the ETC rev limiters for spark\fuel cut as primary rev limiters (mostly drag racing centered but some circle track racing as well when constantly running engines at\near rev limits).............also why Ford themselves only used these cast iron\metal designed chain tensioners in any Modular engine they deemed used for strictly performance (like the 03-04 Terminator 4.6L SC, 07-12 GT500 5.4L SC & 13-14 GT500 Trinity 5.8L SC & all Coyote\Coyote-variant engines from 11-present....).

The plungers in the cast iron\metal tensioners were designed w\ an oil metering plate under them to meter oil flow into the plunger\plunger bore then Ford installed a rubber piece that sits on top of the internal plunger spring & covers the plunger exit (or in reality, a vent) port in top of the plunger but this piece has spiral grooves cut into it to allow any trapped air to bleed out until oil gets there thus seals this off, so in effect the plunger would be hydro locked once extended in place under load as long as the EOP was there (the metering plate controlled the oil leakoff rate to allow the plunger to not become a rigid, solid fixture when extended & under pressure (thus no 1-way check like in a lash adjuster) but would allow a slow controlled compression when needed to keep from instantaneously shock loading the chain during rapid crankshaft accel\decel thus momentarily over tensioning it to keep from overly stretching\breaking it while at the same time prevent the chain from excess flopping due to excessive plunger over compression) thus this other orifice in tensioner body is where the chain gets it's continuous oiling from.
So, in essence, the ratchet stand was a secondary purpose part as long as the plungers properly hydro locked.......the chain guide would never rest on the ratchet stand at all except in a severe chain loading scenario (very rare in OEM-designed\tested usage cases but guaranteed to occur when using 2-steps\NM2B WOT boxes or using spark\fuel cut as primary rev limiting eventually overloading the ratchet stand & causing damage under prolonged use) or when the engine was shut off & EOP bled off (most common) .......thus would also protect the plastic stationary chain guides.......especially B1 chain guide.......from getting busted\broken from initial EOP loading the tensioner plungers back up (also what the internal plunger spring is for as well) causing excessive chain whip on startup.

So, these Ford 2V cast iron chain tensioners are designed by Ford to hold the cam timing in place\steady once EOP loaded them whereas the plastic units can't due to having to try to maintain sufficient EOP loading under plunger to hold cam timing steady while at the same time providing sufficient chain oiling thru the plunger orifice port in top of plunger (so EOP is trying to keep up w\ a designed EOP orifice leakoff rate at the same time trying to maintain sufficient tension loading under the plunger thus on the guide\chain) so these plungers in the plastic tensioners will not hydro lock in place at all so cam timing will fluctuate constantly under load (which I can easily see all this going on thru my datalogs on a 3V Modular w\ 180,000+ mi on it......) thus is highly susceptible to EOP swings thus swinging cam timing & momentarily cavitating cam phasers under load causing some false knock to occur from KS voltages momentarily dropping randomly then returning to normal tracing falsely emulating a detonation sine wave down avg signal frequency in which the ECU determines to be cyl knock if signal frequency avg is outside of the non-accelerated\decelerated down avg frequency filter setting when there isn't any & momentarily cuts spark timing then immediately returns it w\o going thru the knock spark timing recovery process algorithm (true cyl knock\detonation emits a KS-generated electrical frequency rapid up\down sine wave that can't be seen visually in the datalog tracing but the ECU can "see" thus detect it......then will implement the stair-stepped spark timing recovery process algorithm once the real knock stops)......especially during off idle & part throttle low RPM operations where the operational EOP is at its lowest (also have recorded on datalogs)..........while also allowing the chains to become excessively loose during shut down when EOP is bled off (especially when the internal plunger spring tension weakens from constant heat cycling over time.....have physically witnessed this starting to occur on B1 during my FRPP Hot Rod cam install which is what kicked off gathering all the parts to do this timing refresh work.......) since there is nothing stopping the oil from draining out allowing the chains to get whipped around when engine is starting w\o EOP established thus excessively striking the plastic chain guides (notably B1 stationary guide as the chain whips into this guide, B2 stationary guide is inverted thus the chain whips away from this guide under the same loading.....why B1 guide is the 1 that gets broken the majority of the time in most 4.6L\5.4L 3V Modulars) causing guide breakage eventually over time (this is worse in the 5.4L 3V Tritons due to the longer chains used due to taller block deck heights.....).

This action has got to be robbing available engine HP\TQ across the board due to excessively unstable cam timing in both the 4.6L & 5.4L 3V Modulars & gets progressively worse as they age out...................Ford deemed this acceptable for a production line 3V Modular not being purposed for true performance usage (like normal daily driving\towing) but is inadequate for any Modular being purposed for performance use........thus Ford used these plastic chain tensioners in all production line 4.6L\5.4L 3V Modulars to solely cut production costs (cheaper to produce).........these plastic chain tensioners don't provide any tangible performance benefits at all...........only the cast iron\metal chain tensioners do.........Ford plainly knew this.......they designed\created both of them.

I'll be finding this out myself (recording it as well) soon in the near future, Lord willing.............even though Ford themselves has already quantified\proven this thru their designs.........so why did using these cast iron tensioners w\ ratchets in a 3V even become a debate at all? Every front timing component in a 4.6L 3V, outside of the cam phasers & oil pump, are OEM Ford 2V designed timing components thus the cast iron tensioners w\ ratchets are a natural fit\operationally sound replacement component...........

This shouldn't have even\never been\become a debate period IMHO after seeing this Ford internal design myself..............if performance is your goal w\ these 3V's, the OEM Ford 2V cast iron chain tensioner w\ the ratchets is THE 1 to go to, period.... end of story.......whether the ratchets are used untouched or whether the ratchets are modded in conjunction w\ installing these plunger spacers as none of this affects\changes the basic original Ford-design focus of the plungers hydro locking under the chain guides once EOP is applied & plungers filled\ extended & fully bled out to remove chain slack thus properly tensioned........which steadies\maintains the engine's cam timing accuracy under varying loads.......which is the MAIN thing for performance purposes.......the rest is extra but just as important IMHO.

If longevity is your goal & only want to do this timing refresh work 1 time but retain all the performance advantages while eliminating all the known timing deficiencies\shortcomings, IMHO the Ford 2V cast iron chain tensioners w\ ratchets is also your go to (this is my goal)..........whether 1.) used untouched if no 2-step\WOT box or bypassed ETC rev limiter is employed or 2.) ratchets modified in conjunction w\ plunger spacers installed if a 2-step\WOT box or bypassed ETC rev limiter is used up front or not immediately installed\used but may\could potentially be employed later on in future (my way of thinking as I'll never say never...).......IMHO just modding the ratchets alone won't stop the plastic guide breakage if a 2-step\NM2B WOT box or bypassing the ETC rev limiter is employed & routinely thrashed.......IMHO is why the plunger spacers were designed\created to be used w\ the modded ratchets in these 2V cast iron tensioners.
Then going forward, the only reasoning for pulling the front timing cover off again is to remove all existing modified timing components w\ ARP hardware to swap over to a rebuilt short or long block engine......including the modified HV oil pump........thus the "buy once cry once" adage.......

If your goal is to do this work as cheap as you can, then stick w\ the plastic chain tensioners as there isn't any performance advantage associated w\ their use..............IOW's, status quo...............

I suspect the old verbage..................."swallowing a camel but choking on a gnat"......... w\ the ratchet stand being the gnat seems to be the appropriate response as to why these became such a huge debate topic........the reality is, w\o a 2-step or WOT box used or bypassed ETC rev limiter in the tune--thus racing is the central theme, not daily driving usage, the ratchet stand by design is a NON ISSUE......thus a "gnat".

Anything done to the plastic chain tensioners WILL NOT achieve this aspect simply due to their internal plunger design which cannot be changed........except to replace them w\ the cast iron units. You can cheat this to some extent by using a higher viscosity oil to offset the bleed off rate to increase the chain tension from EOP but to fully resolve it you have to replace them w\ the cast iron tensioners...........

My 2 cents FWIW to this "debate" going forward........................I know I'm not typing anything here that you, lwarrior1016, don't already know.......but once I saw the internal plunger design for myself, my mechanical engineering mindset filled in the rest as it was that obvious. I plan to take a couple of pictures of these internal parts for my records......didn't think to do it the 1st time when I disassembled 1 of the cast iron tensioners to look inside the plunger bore & plunger body...............

Also typed for those so interested................
 

GambleS197

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Hey lwarrior1016,

I got my set of 4.6L\5.4L cast iron tensioner plunger spacers in last week & pulled out my set of cast iron tensioners to see how these install..........what I saw when I pulled the plungers out of the tensioner bodies has answered a LOT of other questions I had surrounding these.......like why the "extra" chain oiling orifice in the tensioner body for 1..........that is not present on any Ford 3V Modular plastic chain tensioner.

Now I figured out\know exactly how Ford had initially designed these cast iron tensioners to operate & now even more, I understand that Ford knew they were making a substandard chain tensioner when they designed\used the plastic units for the production line 4.6L\5.4L 3V Modulars & why the 2V Modulars ran so long w\o timing & guide issues.....until folks started using 2-steps\NM2B WOT boxes or tuners sidestepping the ETC rev limiters for spark\fuel cut as primary rev limiters (mostly drag racing centered but some circle track racing as well when constantly running engines at\near rev limits).............also why Ford themselves only used these cast iron\metal designed chain tensioners in any Modular engine they deemed used for strictly performance (like the 03-04 Terminator 4.6L SC, 07-12 GT500 5.4L SC & 13-14 GT500 Trinity 5.8L SC & all Coyote\Coyote-variant engines from 11-present....).

The plungers in the cast iron\metal tensioners were designed w\ an oil metering plate under them to meter oil flow into the plunger\plunger bore then Ford installed a rubber piece that sits on top of the internal plunger spring & covers the plunger exit (or in reality, a vent) port in top of the plunger but this piece has spiral grooves cut into it to allow any trapped air to bleed out until oil gets there thus seals this off, so in effect the plunger would be hydro locked once extended in place under load as long as the EOP was there (the metering plate controlled the oil leakoff rate to allow the plunger to not become a rigid, solid fixture when extended & under pressure (thus no 1-way check like in a lash adjuster) but would allow a slow controlled compression when needed to keep from instantaneously shock loading the chain during rapid crankshaft accel\decel thus momentarily over tensioning it to keep from overly stretching\breaking it while at the same time prevent the chain from excess flopping due to excessive plunger over compression) thus this other orifice in tensioner body is where the chain gets it's continuous oiling from.
So, in essence, the ratchet stand was a secondary purpose part as long as the plungers properly hydro locked.......the chain guide would never rest on the ratchet stand at all except in a severe chain loading scenario (very rare in OEM-designed\tested usage cases but guaranteed to occur when using 2-steps\NM2B WOT boxes or using spark\fuel cut as primary rev limiting eventually overloading the ratchet stand & causing damage under prolonged use) or when the engine was shut off & EOP bled off (most common) .......thus would also protect the plastic stationary chain guides.......especially B1 chain guide.......from getting busted\broken from initial EOP loading the tensioner plungers back up (also what the internal plunger spring is for as well) causing excessive chain whip on startup.

So, these Ford 2V cast iron chain tensioners are designed by Ford to hold the cam timing in place\steady once EOP loaded them whereas the plastic units can't due to having to try to maintain sufficient EOP loading under plunger to hold cam timing steady while at the same time providing sufficient chain oiling thru the plunger orifice port in top of plunger (so EOP is trying to keep up w\ a designed EOP orifice leakoff rate at the same time trying to maintain sufficient tension loading under the plunger thus on the guide\chain) so these plungers in the plastic tensioners will not hydro lock in place at all so cam timing will fluctuate constantly under load (which I can easily see all this going on thru my datalogs on a 3V Modular w\ 180,000+ mi on it......) thus is highly susceptible to EOP swings thus swinging cam timing & momentarily cavitating cam phasers under load causing some false knock to occur from KS voltages momentarily dropping randomly then returning to normal tracing falsely emulating a detonation sine wave down avg signal frequency in which the ECU determines to be cyl knock if signal frequency avg is outside of the non-accelerated\decelerated down avg frequency filter setting when there isn't any & momentarily cuts spark timing then immediately returns it w\o going thru the knock spark timing recovery process algorithm (true cyl knock\detonation emits a KS-generated electrical frequency rapid up\down sine wave that can't be seen visually in the datalog tracing but the ECU can "see" thus detect it......then will implement the stair-stepped spark timing recovery process algorithm once the real knock stops)......especially during off idle & part throttle low RPM operations where the operational EOP is at its lowest (also have recorded on datalogs)..........while also allowing the chains to become excessively loose during shut down when EOP is bled off (especially when the internal plunger spring tension weakens from constant heat cycling over time.....have physically witnessed this starting to occur on B1 during my FRPP Hot Rod cam install which is what kicked off gathering all the parts to do this timing refresh work.......) since there is nothing stopping the oil from draining out allowing the chains to get whipped around when engine is starting w\o EOP established thus excessively striking the plastic chain guides (notably B1 stationary guide as the chain whips into this guide, B2 stationary guide is inverted thus the chain whips away from this guide under the same loading.....why B1 guide is the 1 that gets broken the majority of the time in most 4.6L\5.4L 3V Modulars) causing guide breakage eventually over time (this is worse in the 5.4L 3V Tritons due to the longer chains used due to taller block deck heights.....).

This action has got to be robbing available engine HP\TQ across the board due to excessively unstable cam timing in both the 4.6L & 5.4L 3V Modulars & gets progressively worse as they age out...................Ford deemed this acceptable for a production line 3V Modular not being purposed for true performance usage (like normal daily driving\towing) but is inadequate for any Modular being purposed for performance use........thus Ford used these plastic chain tensioners in all production line 4.6L\5.4L 3V Modulars to solely cut production costs (cheaper to produce).........these plastic chain tensioners don't provide any tangible performance benefits at all...........only the cast iron\metal chain tensioners do.........Ford plainly knew this.......they designed\created both of them.

I'll be finding this out myself (recording it as well) soon in the near future, Lord willing.............even though Ford themselves has already quantified\proven this thru their designs.........so why did using these cast iron tensioners w\ ratchets in a 3V even become a debate at all? Every front timing component in a 4.6L 3V, outside of the cam phasers & oil pump, are OEM Ford 2V designed timing components thus the cast iron tensioners w\ ratchets are a natural fit\operationally sound replacement component...........

This shouldn't have even\never been\become a debate period IMHO after seeing this Ford internal design myself..............if performance is your goal w\ these 3V's, the OEM Ford 2V cast iron chain tensioner w\ the ratchets is THE 1 to go to, period.... end of story.......whether the ratchets are used untouched or whether the ratchets are modded in conjunction w\ installing these plunger spacers as none of this affects\changes the basic original Ford-design focus of the plungers hydro locking under the chain guides once EOP is applied & plungers filled\ extended & fully bled out to remove chain slack thus properly tensioned........which steadies\maintains the engine's cam timing accuracy under varying loads.......which is the MAIN thing for performance purposes.......the rest is extra but just as important IMHO.

If longevity is your goal & only want to do this timing refresh work 1 time but retain all the performance advantages while eliminating all the known timing deficiencies\shortcomings, IMHO the Ford 2V cast iron chain tensioners w\ ratchets is also your go to (this is my goal)..........whether 1.) used untouched if no 2-step\WOT box or bypassed ETC rev limiter is employed or 2.) ratchets modified in conjunction w\ plunger spacers installed if a 2-step\WOT box or bypassed ETC rev limiter is used up front or not immediately installed\used but may\could potentially be employed later on in future (my way of thinking as I'll never say never...).......IMHO just modding the ratchets alone won't stop the plastic guide breakage if a 2-step\NM2B WOT box or bypassing the ETC rev limiter is employed & routinely thrashed.......IMHO is why the plunger spacers were designed\created to be used w\ the modded ratchets in these 2V cast iron tensioners.
Then going forward, the only reasoning for pulling the front timing cover off again is to remove all existing modified timing components w\ ARP hardware to swap over to a rebuilt short or long block engine......including the modified HV oil pump........thus the "buy once cry once" adage.......

If your goal is to do this work as cheap as you can, then stick w\ the plastic chain tensioners as there isn't any performance advantage associated w\ their use..............IOW's, status quo...............

I suspect the old verbage..................."swallowing a camel but choking on a gnat"......... w\ the ratchet stand being the gnat seems to be the appropriate response as to why these became such a huge debate topic........the reality is, w\o a 2-step or WOT box used or bypassed ETC rev limiter in the tune--thus racing is the central theme, not daily driving usage, the ratchet stand by design is a NON ISSUE......thus a "gnat".

Anything done to the plastic chain tensioners WILL NOT achieve this aspect simply due to their internal plunger design which cannot be changed........except to replace them w\ the cast iron units. You can cheat this to some extent by using a higher viscosity oil to offset the bleed off rate to increase the chain tension from EOP but to fully resolve it you have to replace them w\ the cast iron tensioners...........

My 2 cents FWIW to this "debate" going forward........................I know I'm not typing anything here that you, lwarrior1016, don't already know.......but once I saw the internal plunger design for myself, my mechanical engineering mindset filled in the rest as it was that obvious. I plan to take a couple of pictures of these internal parts for my records......didn't think to do it the 1st time when I disassembled 1 of the cast iron tensioners to look inside the plunger bore & plunger body...............

Also typed for those so interested................
Probably the best write up and explanation I’ve read on the issue thank you for that. I still be believe I will get plunger spacers because as you said “I’ll never say I’ll never need it.”
 

lwarrior1016

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Hey lwarrior1016,

I got my set of 4.6L\5.4L cast iron tensioner plunger spacers in last week & pulled out my set of cast iron tensioners to see how these install..........what I saw when I pulled the plungers out of the tensioner bodies has answered a LOT of other questions I had surrounding these.......like why the "extra" chain oiling orifice in the tensioner body for 1..........that is not present on any Ford 3V Modular plastic chain tensioner.

Now I figured out\know exactly how Ford had initially designed these cast iron tensioners to operate & now even more, I understand that Ford knew they were making a substandard chain tensioner when they designed\used the plastic units for the production line 4.6L\5.4L 3V Modulars & why the 2V Modulars ran so long w\o timing & guide issues.....until folks started using 2-steps\NM2B WOT boxes or tuners sidestepping the ETC rev limiters for spark\fuel cut as primary rev limiters (mostly drag racing centered but some circle track racing as well when constantly running engines at\near rev limits).............also why Ford themselves only used these cast iron\metal designed chain tensioners in any Modular engine they deemed used for strictly performance (like the 03-04 Terminator 4.6L SC, 07-12 GT500 5.4L SC & 13-14 GT500 Trinity 5.8L SC & all Coyote\Coyote-variant engines from 11-present....).

The plungers in the cast iron\metal tensioners were designed w\ an oil metering plate under them to meter oil flow into the plunger\plunger bore then Ford installed a rubber piece that sits on top of the internal plunger spring & covers the plunger exit (or in reality, a vent) port in top of the plunger but this piece has spiral grooves cut into it to allow any trapped air to bleed out until oil gets there thus seals this off, so in effect the plunger would be hydro locked once extended in place under load as long as the EOP was there (the metering plate controlled the oil leakoff rate to allow the plunger to not become a rigid, solid fixture when extended & under pressure (thus no 1-way check like in a lash adjuster) but would allow a slow controlled compression when needed to keep from instantaneously shock loading the chain during rapid crankshaft accel\decel thus momentarily over tensioning it to keep from overly stretching\breaking it while at the same time prevent the chain from excess flopping due to excessive plunger over compression) thus this other orifice in tensioner body is where the chain gets it's continuous oiling from.
So, in essence, the ratchet stand was a secondary purpose part as long as the plungers properly hydro locked.......the chain guide would never rest on the ratchet stand at all except in a severe chain loading scenario (very rare in OEM-designed\tested usage cases but guaranteed to occur when using 2-steps\NM2B WOT boxes or using spark\fuel cut as primary rev limiting eventually overloading the ratchet stand & causing damage under prolonged use) or when the engine was shut off & EOP bled off (most common) .......thus would also protect the plastic stationary chain guides.......especially B1 chain guide.......from getting busted\broken from initial EOP loading the tensioner plungers back up (also what the internal plunger spring is for as well) causing excessive chain whip on startup.

So, these Ford 2V cast iron chain tensioners are designed by Ford to hold the cam timing in place\steady once EOP loaded them whereas the plastic units can't due to having to try to maintain sufficient EOP loading under plunger to hold cam timing steady while at the same time providing sufficient chain oiling thru the plunger orifice port in top of plunger (so EOP is trying to keep up w\ a designed EOP orifice leakoff rate at the same time trying to maintain sufficient tension loading under the plunger thus on the guide\chain) so these plungers in the plastic tensioners will not hydro lock in place at all so cam timing will fluctuate constantly under load (which I can easily see all this going on thru my datalogs on a 3V Modular w\ 180,000+ mi on it......) thus is highly susceptible to EOP swings thus swinging cam timing & momentarily cavitating cam phasers under load causing some false knock to occur from KS voltages momentarily dropping randomly then returning to normal tracing falsely emulating a detonation sine wave down avg signal frequency in which the ECU determines to be cyl knock if signal frequency avg is outside of the non-accelerated\decelerated down avg frequency filter setting when there isn't any & momentarily cuts spark timing then immediately returns it w\o going thru the knock spark timing recovery process algorithm (true cyl knock\detonation emits a KS-generated electrical frequency rapid up\down sine wave that can't be seen visually in the datalog tracing but the ECU can "see" thus detect it......then will implement the stair-stepped spark timing recovery process algorithm once the real knock stops)......especially during off idle & part throttle low RPM operations where the operational EOP is at its lowest (also have recorded on datalogs)..........while also allowing the chains to become excessively loose during shut down when EOP is bled off (especially when the internal plunger spring tension weakens from constant heat cycling over time.....have physically witnessed this starting to occur on B1 during my FRPP Hot Rod cam install which is what kicked off gathering all the parts to do this timing refresh work.......) since there is nothing stopping the oil from draining out allowing the chains to get whipped around when engine is starting w\o EOP established thus excessively striking the plastic chain guides (notably B1 stationary guide as the chain whips into this guide, B2 stationary guide is inverted thus the chain whips away from this guide under the same loading.....why B1 guide is the 1 that gets broken the majority of the time in most 4.6L\5.4L 3V Modulars) causing guide breakage eventually over time (this is worse in the 5.4L 3V Tritons due to the longer chains used due to taller block deck heights.....).

This action has got to be robbing available engine HP\TQ across the board due to excessively unstable cam timing in both the 4.6L & 5.4L 3V Modulars & gets progressively worse as they age out...................Ford deemed this acceptable for a production line 3V Modular not being purposed for true performance usage (like normal daily driving\towing) but is inadequate for any Modular being purposed for performance use........thus Ford used these plastic chain tensioners in all production line 4.6L\5.4L 3V Modulars to solely cut production costs (cheaper to produce).........these plastic chain tensioners don't provide any tangible performance benefits at all...........only the cast iron\metal chain tensioners do.........Ford plainly knew this.......they designed\created both of them.

I'll be finding this out myself (recording it as well) soon in the near future, Lord willing.............even though Ford themselves has already quantified\proven this thru their designs.........so why did using these cast iron tensioners w\ ratchets in a 3V even become a debate at all? Every front timing component in a 4.6L 3V, outside of the cam phasers & oil pump, are OEM Ford 2V designed timing components thus the cast iron tensioners w\ ratchets are a natural fit\operationally sound replacement component...........

This shouldn't have even\never been\become a debate period IMHO after seeing this Ford internal design myself..............if performance is your goal w\ these 3V's, the OEM Ford 2V cast iron chain tensioner w\ the ratchets is THE 1 to go to, period.... end of story.......whether the ratchets are used untouched or whether the ratchets are modded in conjunction w\ installing these plunger spacers as none of this affects\changes the basic original Ford-design focus of the plungers hydro locking under the chain guides once EOP is applied & plungers filled\ extended & fully bled out to remove chain slack thus properly tensioned........which steadies\maintains the engine's cam timing accuracy under varying loads.......which is the MAIN thing for performance purposes.......the rest is extra but just as important IMHO.

If longevity is your goal & only want to do this timing refresh work 1 time but retain all the performance advantages while eliminating all the known timing deficiencies\shortcomings, IMHO the Ford 2V cast iron chain tensioners w\ ratchets is also your go to (this is my goal)..........whether 1.) used untouched if no 2-step\WOT box or bypassed ETC rev limiter is employed or 2.) ratchets modified in conjunction w\ plunger spacers installed if a 2-step\WOT box or bypassed ETC rev limiter is used up front or not immediately installed\used but may\could potentially be employed later on in future (my way of thinking as I'll never say never...).......IMHO just modding the ratchets alone won't stop the plastic guide breakage if a 2-step\NM2B WOT box or bypassing the ETC rev limiter is employed & routinely thrashed.......IMHO is why the plunger spacers were designed\created to be used w\ the modded ratchets in these 2V cast iron tensioners.
Then going forward, the only reasoning for pulling the front timing cover off again is to remove all existing modified timing components w\ ARP hardware to swap over to a rebuilt short or long block engine......including the modified HV oil pump........thus the "buy once cry once" adage.......

If your goal is to do this work as cheap as you can, then stick w\ the plastic chain tensioners as there isn't any performance advantage associated w\ their use..............IOW's, status quo...............

I suspect the old verbage..................."swallowing a camel but choking on a gnat"......... w\ the ratchet stand being the gnat seems to be the appropriate response as to why these became such a huge debate topic........the reality is, w\o a 2-step or WOT box used or bypassed ETC rev limiter in the tune--thus racing is the central theme, not daily driving usage, the ratchet stand by design is a NON ISSUE......thus a "gnat".

Anything done to the plastic chain tensioners WILL NOT achieve this aspect simply due to their internal plunger design which cannot be changed........except to replace them w\ the cast iron units. You can cheat this to some extent by using a higher viscosity oil to offset the bleed off rate to increase the chain tension from EOP but to fully resolve it you have to replace them w\ the cast iron tensioners...........

My 2 cents FWIW to this "debate" going forward........................I know I'm not typing anything here that you, lwarrior1016, don't already know.......but once I saw the internal plunger design for myself, my mechanical engineering mindset filled in the rest as it was that obvious. I plan to take a couple of pictures of these internal parts for my records......didn't think to do it the 1st time when I disassembled 1 of the cast iron tensioners to look inside the plunger bore & plunger body...............

Also typed for those so interested................
Man, that is a very well written response. I cannot follow that up with anything of substance.

I do remember tearing these tensioners down, and on just about every other forum, everyone agrees the iron tensioners is superior. In every form. It wasn’t until I got on this forum that I saw folks that did not like the iron tensioners.

I do not like the chain slack that shows up in low pressure scenarios. I will use the iron tensioners in all my engines. And have been doing so in all of them that I have built for many years.
 

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