No low end power

Midlife Crises

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I’d leave the cams alone for now and change the gears. 4.10s will make a huge difference in low speed drivability and 3.73 would certainly be better than 3.55.
 

Rich

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4.10's are great for these cars. While I was considering a gear for my swap I thought about 4.56 and I wonder how much better those would have been for acceleration. Maybe the OP should look at a set of FRPP 4.56's.
 

ShelbySteve

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These cars are 400-700lbs heavier than a fox body so the extra torque over the pushrod 5.0 isn't as apparent, no big revelation there.

I couldn't stand the 3.55's with the stock motor, putting in Hot rod cams and keeping the stock gearing is just asking for frustration.
As for what to do gearing wise-are you planning on sticking with the TR3650, or will you upgrade?
Do you drag race it or do you just want a cruiser?

I use 4.10 gears and a 2.97 geared TR6060 in a built motor turbo car, the 3.55's couldn't get the car out of the hole and were awkward AF for 1/8th mile as I was shifting <100ft from the traps. The car was 4/10th's faster with 4.10's even though turbos aren't supposed to like lower gears according to the internet.
On the street, the 3.55's spun just as much as the 4.10's-the 4.10's just made it easier to pedal it and regain control.
Hard to say for now. Going 6 speed is an option and I prefer drag racing over carving corners
 

Rich

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4.10s will make a huge difference in low speed drivability and 3.73 would certainly be better than 3.55.

Agreed, my auto no longer downshifts when I accelerate in 5th, unless I floor it. It gets up and goes pretty quickly for what it is. Much, much better than the stock 3.31's.
 

RED09GT

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Agreed, my auto no longer downshifts when I accelerate in 5th, unless I floor it. It gets up and goes pretty quickly for what it is. Much, much better than the stock 3.31's.
Many 5R55 transmissions have died from full throttle downshifts out of 5th gear. If you want it to survive, click it to whatever gear you want manually and then accelerate. The 2/5 band wearing and the servos leaking are inevitable in the life of a 5R55. Click O/D off when climbing a hill and click O/D off before flooring it and it can survive a lot longer.
 

GlassTop09

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Should’ve posted the dyno sheet. Didn’t even think to look through the receipts and stuff I got with the car. Car has Mac long tubes, Ford racing cai, catted mid pipe with Mac pro chamber, borla axle back, bbk ud pulleys, and hot Rod cams. Assuming it still has the stock TB and it still has the 3.55 gears. The tq down low is terrible down low and I know it could be the cam profile among other things.

Don’t have much experience here so does anyone think I should get ahold of Lito for a new tune or go ahead and do a tb and gears...or all of the above?
View attachment 76204
I had a hunch that your car has been tuned on a dyno, that's why I typed what I typed in my earlier post. Not to start a flame war here but when you're looking at a dyno plot of a 3V, just know you're not looking at the tune mapping results for actual low RPM normal driving w\ TBA (throttle blade angle) <30% open which is within the IMRC closed tune map (CMCV closed to simulate a long intake runner for low speed TQ & for emissions...daily driving operation), your dyno sheet curves represent mapping w\ the TBA at WOT (IMRC open tune mapping to simulate a short intake runner for hi RPM power so CMCV are full open) so the PCM is not in CL (adaptive fueling to maintain optimum AFR of 14.64) but is in OL (static fueling mapping), it's not using the VCT in dynamic mode (auto adjust cam timing according to desired load% read from the accelerator pedal thus PCM calculated load% w\ emissions goals programmed into it) but the VCT is static mapped so is retarding cam timing manually according to specific RPM markers (meaning that the VCT retard amount is specified to move a certain set amount of degrees until the RPM's cross a set marker at which then it will retard the cams to the next specified set amount of degrees retard...so on & so on until it reaches the last RPM setting marker which is never set for cams to retard in excess of 20* crank max) so what you see on that sheet doesn't actually represent what you're experiencing when driving normally since the normal driving RPM range will be <3000 RPM's & TBA is <30% open so the PCM will not be using the open IMRC mapping but using the IMRC closed mapping that most dyno tuners will usually not be spending a lot of time adjusting this mapping to match up w\ aftermarket camshafts....mostly due to customers not willing to pay for the amount of time dyno tuners would have to put into remapping\testing\revisioning it as well as a dyno can't load replicate this part of the operation well enough for accuracy as opposed to remote tuning (datalogging the engine and\or trans shift points if auto under actual driving conditions which will also take into account YOUR driving habits as well then tuner uses datalog recording to readjust BOTH IMRC close\open tune mappings along w\ other items of interest--rinse & repeat--as many times necessary until optimized for a flat fee) so the tendency of this part of the mapping being mismatched\unoptimized (using IMRC closed VCT mapping set up--which can allow the cam timing to be dynamically retarded up to a max of 60* crank retard from 0* if PCM desires according to sensor input data in relation to it's coded priorities in the firmware) w\ aftermarket cams which use entirely different GI cam timing specs vs the OEM cams unless the aftermarket cams require either phaser limiters which physically limit VCT travel to 20* retard max or phaser lockouts which lock the phasers at 0* completely defeating VCT to prevent PTV clearance issues....these Hot Rod cams are ground to allow full dynamic VCT retard range w\o limiters installed...why they're listed as a "drop in" camshaft set) after a dyno session can be high which isn't gonna help. Any VCT cam timing retard in excess of 20* crank from 0* for these 3V's, regardless of cams used, is NOT INTENDED for low RPM HP\TQ output as you'd be lowering the static cylinder pressure buildup during compression stroke too much....it's for emissions\MPG purposes only (a total of 40* worth). So for those cams that are requiring a phaser limiter be used to limit the max VCT retard range to 20* crank, they're actually doing you a favor concerning low speed HP\TQ....Comp Cams (others as well) knows this to be true. Fortunately this can also be setup to achieve in the tune w\ a "drop in" cam set providing the same benefits so is an option to consider. This is also why bringing in Coyotes into this discussion concerning a 3V is also deceptive because of the Coyotes using Tri-VCT which can move intake & exhaust cams independently of each other thus can change physical intake\exhaust cam open\close timing point positions relative to crankshaft degree rotation (think LSA, ICL, ECL, OL changes relative to 0*) as opposed to 3V's VCT using 1 camshaft per side so moves both intake lobes & exhaust lobes at the same time & the same amount of degree change (but not physically change cam LSA, ICL, ECL or OL relative to 0* as w\ a Coyote) so a Coyote engine can alleviate most all the issues that can cause a 3V to lose more low end HP\TQ than it should thru VCT, especially when emissions get involved (such as EGR functions for starters) so a 3V is at best a balancing act to get\maintain net max low end HP\TQ...even w\ OEM cams. This is 1 area where avg tuners are separated from great tuners concerning the 3V.........

This aspect of Ford's Spanish Oaks PCM operation w\ these 3V's IMHO gets overlooked far too much....especially when aftermarket cams are used & gets tied into a dyno curve discussion which is not entirely accurate. Now this doesn't necessarily change what most have said here concerning these Hot Rod cams vs OEM cams overall (why I also mentioned in my prior posting the GI cam timing point mapping I have done to show\explain where it all starts from) BUT unless the tuning has been properly done in the IMRC closed map for VCT to match to the Hot Rod cam specs well it can make the low RPM HP\TQ operation much worse......even the OEM cams aren't fully optimized for max low end HP\TQ in this mapping either originally as Ford leans towards the emissions tuning taking a higher priority vs power in this IMRC closed mapping to ensure meeting Fed emissions & MPG stds of the time of manufacture.....this IS a production vehicle at it's core so in order to achieve max low end HP\TQ within this IMRC closed map, regardless of cams used, tuning is required to "refocus" this mapping more towards HP\TQ production & away from emissions\MPG then blend the PCM tune mapping transitions from IMRC closed to IMRC open seamlessly when the TBA >35% open & RPM's exceed 3,000.

You don't have to take my word on this.....just go visit HP Tuner's web site & hit their BBS forums....they have a specific thread dedicated to explaining all this & all the steps to rectify the IMRC closed tune mapping to squeeze max low RPM power out of a 3V, especially when the CMCV's are deleted but can be done w\ the CMCV's still in operation as well........1st discovered\done by HP Tuner master techs back in 2008 when these 3V's were the bomb....

This is why I made the suggestion to consider getting remote tuned to correct any deficiencies found within the IMRC closed mapping that can be making these Hot Rod cams operate worse than what they would be if tuned properly within the IMRC closed mapping (where you're experiencing most of what you've posted) since these Hot Rod cams are what you're currently equipped with & Lito's prices are very good (currently in the $200.00 flat fee range I believe for a NA 3V tune including multiple revisions to get it fully optimized) to try to get you some relief NOW (make it better) w\ what you already have. You're gonna be retuning her anyway once you refit all for FI....so are you gonna suffer w\ her as she is now hating to cruise in her for cars & coffee meets/grocery getting putting excess wear & tear on your clutch\flywheel\PP while you're gathering parts to go FI?

This is your decision to make in the end..............I'm sure that you'll make the best decision that makes sense to you.....

You gonna be very hard pressed to find a local dyno shop to tune your car right w\ these cams for this price. There ARE shop tuners that can do just as good a job tuning but you generally have to pay more for it....depending on the tuner, a lot more to compensate for their time involved.....if they'll spend the time to tune these 3V's anymore (they'll generally make more money tuning Coyotes due to spending far less time tuning to optimization thus tuning more cars within the same time it'd take to fully & properly tune 1 3V on a dyno). Business Admin 101........... 3V tuning is slowly becoming a lost art in the enthusiast world the older they get....just as 2V tuning has already become.

When you hear most folks that state their car runs\drives better & more responsive after Lito tuned it (remote tuned) vs being tuned by a tuner on a dyno or from using a canned tune.....now hopefully you will understand a little better as to why they're saying that.

In closing I'm not trying to sway you into doing anything, just trying to explain to you some of why you're experiencing what you're feeling w\ your car & what can be done to make it better as it can be done within the tune according to the GI cam timing point specs of these Hot Rod cams (assuming all other aspects of your engine is in sound operating condition). As already been stated, if you want the most consistent low end, low speed HP\TQ you can get from your 3V from a cam perspective you gonna have to move away from these Hot Rod cams...or most any cam that tends to cause engine to excessively lope below 1,000 RPM's due to the EVO cam timing point during the power stroke being ahead of the 90* crank throw position from BDC (actual Hot Rod EVO point @ 97* BBDC using it's advertised duration specs....or you can get a copy of Ford's Hot Rod cam installation pdf which has this info included for both the Hot Rods & the OEM cams as well) w\ the VCT holding the cams at 0* timing.....contributing to the bucking you're experiencing as well as a small loss of low end HP\TQ from lost leverage vs the OEM cams when held at the same VCT 0* cam timing for comparison, their EVO cam timing point during power stroke is at 80* BBDC using it's advertised duration specs.....a full 10* AFTER the crank's throw has traveled thru it's 90* position (17* after the Hot Rod cams have already bled off cylinder pressure thru the open EV into the exhaust) allowing FULL leveraging of the cylinder expansion force application to the crankshaft from the piston at max crank throw length which will also allow the next firing cylinder in sequence to start applying it's force to it's crank journal throw after apex swing during it's power stroke BEFORE the previous fired cylinder's force is completely bled off when the EVO event starts occurring, smoothing out the power pulse transitions thus no bucking tendency......with more total net TQ thus net HP applied at the same RPM all else being equal....wonder why the OEM cams can provide more low end HP\TQ vs these Hot Rod cams in a cross-planed crank 3V (fires every 90* of crank rotation)? That's what is ground into these cams which the 3V's VCT cannot change (unlike a Coyote using Tri-VCT) but if not remapped properly within the IMRC closed tune mapping can make the differences much worse. Where the OEM cams will start losing ground against the Hot Rod cams is during mid\hi RPM operation when the VCT starts retarding the cam timing to maintain good cylinder AF fill volume rates during the intake stroke at speed by taking advantage of the higher exhaust scavaging velocities (LTH's improve on this even more vs the stock manifolds as long as the intake side isn't restricting airflow) & earlier IVO cam timing points available thru the larger cam OL created by it as well as correcting the issue w\ the EVO opening ahead of the crank throw at 90* during the power stroke to gain back some lost TQ at the expense of a little cylinder compression pressure buildup loss from retarding the IVC timing point during compression stroke at the same time by the same amount of degree retard losing some potential TQ to flatten out the net TQ decline across the upper RPM curve to drive the net HP higher as that is where the Hot Rod's cam timing points are optimized to provide vs the OEM cams....IOW's for improved racing performance while in NA form....both strip & track but not so much for normal low RPM street usage....their worse when used w\ a manual trans vs an automatic due to the auto's converter TQ multiplication & trans gearing ratios...but even an auto won't necessarily mask all the bucking tendency at low RPM's w\ these Hot Rod cams w\o a little help from some tuning.... But once you stage them engine RPM's above 3,000 & up along w\ the TBA exceeding 35% open w\ them Hot Rod cams to get the PCM to start using the IMRC open tune mapping (where your prior tuner did most of the optimizing at & is reflected somewhat by your dyno sheet results....hopefully the manual VCT cam timing mapping is set up according to Ford's published recommended WOT settings for these Hot Rod cams to achieve max mid\high RPM HP\TQ), get ready for a good ride....which I'm sure puts a smile on your face! Just not so much when grocery getting in your 3V steed......
Of course a PD blower can mask all of this easily if desired..........but won't correct it. Only a camshaft changeout w\ the proper physical GI cam timing points can correct it....

Now if you understand all this & can fully accept the side effects then sai le vie', enjoy that idle chop & be happy cause in the end your happiness is all that should matter to you IMHO......

Just an example of why thru the actual physical cam IVO, IVC, EVO, EVC timing point characteristics in relation to crankshaft rotation (that LSA, ICL, ECL, OL, cam advance & valve duration are all derived from in relation to the cam 0* degree mark which is the center mark of the LSA & what the middle tone ring finger on the 3 finger side of the cam phaser represents to the PCM when phasing the cam timing thru VCT to the crank timing) affecting the net outcome............... Everything can't be fixed thru the tune alone on a 3V but some of the side effects can be minimized to a certain extent thru the tune while still giving acceptable overall performance.

But them Hot Rod cams do sound good when idling though.....damn good!

Hope this helps.:beer:
 

RED09GT

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That is a very thorough walk through.

How much time did it take to write it all down?
 

Dino Dino Bambino

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The problem with the Hot Rod cams is that due to the longer duration and higher valve lift, the WOT cam timing remains 7 degrees retarded at lower rpm to avoid piston to valve contact whereas the stock cams are at zero.
A good tuner might be able to reduce the degree of low rev torque loss and improve driveability by playing with the VCT programming, but you can't have both a lopey cam AND still expect smooth low rpm engine operation.
The TiVCT system on the Coyote can adjust the lobe separation angle of the cams as well as the cam advance/retard for each cam due to it having separate intake and exhaust cams plus phasers on all of them. That allows the Coyote to have such a wide power band with good torque and driveability at low rpm, and the ability to pull to 7500rpm. The 3V, with only one cam per cylinder bank (SOHC), has to be content with a fixed lobe separation angle ground into it with only the cam advance/retard being adjustable. It's a world better than the SOHC 4.6 2V across the whole rpm range, and better than the SOHC 4.6 4V at lower rpm while matching it at higher rpm, but it can't hold a candle to the Coyote no matter how many N/A mods you do to it.
 

ShelbySteve

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I had a hunch that your car has been tuned on a dyno, that's why I typed what I typed in my earlier post. Not to start a flame war here but when you're looking at a dyno plot of a 3V, just know you're not looking at the tune mapping results for actual low RPM normal driving w\ TBA (throttle blade angle) <30% open which is within the IMRC closed tune map (CMCV closed to simulate a long intake runner for low speed TQ & for emissions...daily driving operation), your dyno sheet curves represent mapping w\ the TBA at WOT (IMRC open tune mapping to simulate a short intake runner for hi RPM power so CMCV are full open) so the PCM is not in CL (adaptive fueling to maintain optimum AFR of 14.64) but is in OL (static fueling mapping), it's not using the VCT in dynamic mode (auto adjust cam timing according to desired load% read from the accelerator pedal thus PCM calculated load% w\ emissions goals programmed into it) but the VCT is static mapped so is retarding cam timing manually according to specific RPM markers (meaning that the VCT retard amount is specified to move a certain set amount of degrees until the RPM's cross a set marker at which then it will retard the cams to the next specified set amount of degrees retard...so on & so on until it reaches the last RPM setting marker which is never set for cams to retard in excess of 20* crank max) so what you see on that sheet doesn't actually represent what you're experiencing when driving normally since the normal driving RPM range will be <3000 RPM's & TBA is <30% open so the PCM will not be using the open IMRC mapping but using the IMRC closed mapping that most dyno tuners will usually not be spending a lot of time adjusting this mapping to match up w\ aftermarket camshafts....mostly due to customers not willing to pay for the amount of time dyno tuners would have to put into remapping\testing\revisioning it as well as a dyno can't load replicate this part of the operation well enough for accuracy as opposed to remote tuning (datalogging the engine and\or trans shift points if auto under actual driving conditions which will also take into account YOUR driving habits as well then tuner uses datalog recording to readjust BOTH IMRC close\open tune mappings along w\ other items of interest--rinse & repeat--as many times necessary until optimized for a flat fee) so the tendency of this part of the mapping being mismatched\unoptimized (using IMRC closed VCT mapping set up--which can allow the cam timing to be dynamically retarded up to a max of 60* crank retard from 0* if PCM desires according to sensor input data in relation to it's coded priorities in the firmware) w\ aftermarket cams which use entirely different GI cam timing specs vs the OEM cams unless the aftermarket cams require either phaser limiters which physically limit VCT travel to 20* retard max or phaser lockouts which lock the phasers at 0* completely defeating VCT to prevent PTV clearance issues....these Hot Rod cams are ground to allow full dynamic VCT retard range w\o limiters installed...why they're listed as a "drop in" camshaft set) after a dyno session can be high which isn't gonna help. Any VCT cam timing retard in excess of 20* crank from 0* for these 3V's, regardless of cams used, is NOT INTENDED for low RPM HP\TQ output as you'd be lowering the static cylinder pressure buildup during compression stroke too much....it's for emissions\MPG purposes only (a total of 40* worth). So for those cams that are requiring a phaser limiter be used to limit the max VCT retard range to 20* crank, they're actually doing you a favor concerning low speed HP\TQ....Comp Cams (others as well) knows this to be true. Fortunately this can also be setup to achieve in the tune w\ a "drop in" cam set providing the same benefits so is an option to consider. This is also why bringing in Coyotes into this discussion concerning a 3V is also deceptive because of the Coyotes using Tri-VCT which can move intake & exhaust cams independently of each other thus can change physical intake\exhaust cam open\close timing point positions relative to crankshaft degree rotation (think LSA, ICL, ECL, OL changes relative to 0*) as opposed to 3V's VCT using 1 camshaft per side so moves both intake lobes & exhaust lobes at the same time & the same amount of degree change (but not physically change cam LSA, ICL, ECL or OL relative to 0* as w\ a Coyote) so a Coyote engine can alleviate most all the issues that can cause a 3V to lose more low end HP\TQ than it should thru VCT, especially when emissions get involved (such as EGR functions for starters) so a 3V is at best a balancing act to get\maintain net max low end HP\TQ...even w\ OEM cams. This is 1 area where avg tuners are separated from great tuners concerning the 3V.........

This aspect of Ford's Spanish Oaks PCM operation w\ these 3V's IMHO gets overlooked far too much....especially when aftermarket cams are used & gets tied into a dyno curve discussion which is not entirely accurate. Now this doesn't necessarily change what most have said here concerning these Hot Rod cams vs OEM cams overall (why I also mentioned in my prior posting the GI cam timing point mapping I have done to show\explain where it all starts from) BUT unless the tuning has been properly done in the IMRC closed map for VCT to match to the Hot Rod cam specs well it can make the low RPM HP\TQ operation much worse......even the OEM cams aren't fully optimized for max low end HP\TQ in this mapping either originally as Ford leans towards the emissions tuning taking a higher priority vs power in this IMRC closed mapping to ensure meeting Fed emissions & MPG stds of the time of manufacture.....this IS a production vehicle at it's core so in order to achieve max low end HP\TQ within this IMRC closed map, regardless of cams used, tuning is required to "refocus" this mapping more towards HP\TQ production & away from emissions\MPG then blend the PCM tune mapping transitions from IMRC closed to IMRC open seamlessly when the TBA >35% open & RPM's exceed 3,000.

You don't have to take my word on this.....just go visit HP Tuner's web site & hit their BBS forums....they have a specific thread dedicated to explaining all this & all the steps to rectify the IMRC closed tune mapping to squeeze max low RPM power out of a 3V, especially when the CMCV's are deleted but can be done w\ the CMCV's still in operation as well........1st discovered\done by HP Tuner master techs back in 2008 when these 3V's were the bomb....

This is why I made the suggestion to consider getting remote tuned to correct any deficiencies found within the IMRC closed mapping that can be making these Hot Rod cams operate worse than what they would be if tuned properly within the IMRC closed mapping (where you're experiencing most of what you've posted) since these Hot Rod cams are what you're currently equipped with & Lito's prices are very good (currently in the $200.00 flat fee range I believe for a NA 3V tune including multiple revisions to get it fully optimized) to try to get you some relief NOW (make it better) w\ what you already have. You're gonna be retuning her anyway once you refit all for FI....so are you gonna suffer w\ her as she is now hating to cruise in her for cars & coffee meets/grocery getting putting excess wear & tear on your clutch\flywheel\PP while you're gathering parts to go FI?

This is your decision to make in the end..............I'm sure that you'll make the best decision that makes sense to you.....

You gonna be very hard pressed to find a local dyno shop to tune your car right w\ these cams for this price. There ARE shop tuners that can do just as good a job tuning but you generally have to pay more for it....depending on the tuner, a lot more to compensate for their time involved.....if they'll spend the time to tune these 3V's anymore (they'll generally make more money tuning Coyotes due to spending far less time tuning to optimization thus tuning more cars within the same time it'd take to fully & properly tune 1 3V on a dyno). Business Admin 101........... 3V tuning is slowly becoming a lost art in the enthusiast world the older they get....just as 2V tuning has already become.

When you hear most folks that state their car runs\drives better & more responsive after Lito tuned it (remote tuned) vs being tuned by a tuner on a dyno or from using a canned tune.....now hopefully you will understand a little better as to why they're saying that.

In closing I'm not trying to sway you into doing anything, just trying to explain to you some of why you're experiencing what you're feeling w\ your car & what can be done to make it better as it can be done within the tune according to the GI cam timing point specs of these Hot Rod cams (assuming all other aspects of your engine is in sound operating condition). As already been stated, if you want the most consistent low end, low speed HP\TQ you can get from your 3V from a cam perspective you gonna have to move away from these Hot Rod cams...or most any cam that tends to cause engine to excessively lope below 1,000 RPM's due to the EVO cam timing point during the power stroke being ahead of the 90* crank throw position from BDC (actual Hot Rod EVO point @ 97* BBDC using it's advertised duration specs....or you can get a copy of Ford's Hot Rod cam installation pdf which has this info included for both the Hot Rods & the OEM cams as well) w\ the VCT holding the cams at 0* timing.....contributing to the bucking you're experiencing as well as a small loss of low end HP\TQ from lost leverage vs the OEM cams when held at the same VCT 0* cam timing for comparison, their EVO cam timing point during power stroke is at 80* BBDC using it's advertised duration specs.....a full 10* AFTER the crank's throw has traveled thru it's 90* position (17* after the Hot Rod cams have already bled off cylinder pressure thru the open EV into the exhaust) allowing FULL leveraging of the cylinder expansion force application to the crankshaft from the piston at max crank throw length which will also allow the next firing cylinder in sequence to start applying it's force to it's crank journal throw after apex swing during it's power stroke BEFORE the previous fired cylinder's force is completely bled off when the EVO event starts occurring, smoothing out the power pulse transitions thus no bucking tendency......with more total net TQ thus net HP applied at the same RPM all else being equal....wonder why the OEM cams can provide more low end HP\TQ vs these Hot Rod cams in a cross-planed crank 3V (fires every 90* of crank rotation)? That's what is ground into these cams which the 3V's VCT cannot change (unlike a Coyote using Tri-VCT) but if not remapped properly within the IMRC closed tune mapping can make the differences much worse. Where the OEM cams will start losing ground against the Hot Rod cams is during mid\hi RPM operation when the VCT starts retarding the cam timing to maintain good cylinder AF fill volume rates during the intake stroke at speed by taking advantage of the higher exhaust scavaging velocities (LTH's improve on this even more vs the stock manifolds as long as the intake side isn't restricting airflow) & earlier IVO cam timing points available thru the larger cam OL created by it as well as correcting the issue w\ the EVO opening ahead of the crank throw at 90* during the power stroke to gain back some lost TQ at the expense of a little cylinder compression pressure buildup loss from retarding the IVC timing point during compression stroke at the same time by the same amount of degree retard losing some potential TQ to flatten out the net TQ decline across the upper RPM curve to drive the net HP higher as that is where the Hot Rod's cam timing points are optimized to provide vs the OEM cams....IOW's for improved racing performance while in NA form....both strip & track but not so much for normal low RPM street usage....their worse when used w\ a manual trans vs an automatic due to the auto's converter TQ multiplication & trans gearing ratios...but even an auto won't necessarily mask all the bucking tendency at low RPM's w\ these Hot Rod cams w\o a little help from some tuning.... But once you stage them engine RPM's above 3,000 & up along w\ the TBA exceeding 35% open w\ them Hot Rod cams to get the PCM to start using the IMRC open tune mapping (where your prior tuner did most of the optimizing at & is reflected somewhat by your dyno sheet results....hopefully the manual VCT cam timing mapping is set up according to Ford's published recommended WOT settings for these Hot Rod cams to achieve max mid\high RPM HP\TQ), get ready for a good ride....which I'm sure puts a smile on your face! Just not so much when grocery getting in your 3V steed......
Of course a PD blower can mask all of this easily if desired..........but won't correct it. Only a camshaft changeout w\ the proper physical GI cam timing points can correct it....

Now if you understand all this & can fully accept the side effects then sai le vie', enjoy that idle chop & be happy cause in the end your happiness is all that should matter to you IMHO......

Just an example of why thru the actual physical cam IVO, IVC, EVO, EVC timing point characteristics in relation to crankshaft rotation (that LSA, ICL, ECL, OL, cam advance & valve duration are all derived from in relation to the cam 0* degree mark which is the center mark of the LSA & what the middle tone ring finger on the 3 finger side of the cam phaser represents to the PCM when phasing the cam timing thru VCT to the crank timing) affecting the net outcome............... Everything can't be fixed thru the tune alone on a 3V but some of the side effects can be minimized to a certain extent thru the tune while still giving acceptable overall performance.

But them Hot Rod cams do sound good when idling though.....damn good!

Hope this helps.:beer:
While the tuning and very specific details has me lost in the sauce, I got the just of the benefits of having Lito tune it. I already had it in mind as I’ve read nothing but good things about his tunes. Only possible issue is that my SCT tuner is an old one with the analog lcd screen, but I seen that it at least can do data logging and I’ll just need to get the cord to hook it up to a laptop. Would I be better off getting a newer tuner since I’ll be using it going forward with other modifications?
 

Rich

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Many 5R55 transmissions have died from full throttle downshifts out of 5th gear. If you want it to survive, click it to whatever gear you want manually and then accelerate. The 2/5 band wearing and the servos leaking are inevitable in the life of a 5R55. Click O/D off when climbing a hill and click O/D off before flooring it and it can survive a lot longer.
I knew about the servo bore issue but I did not know the 5th gear downshifts at wide open throttle problem. Thank you for that info.
 

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