Intercooling my Setup - Add Boost or Timing?

[Swarzkopf]

So I'm throwing a CX Racing air to air intercooler on my setup. Currently, in short my setup is:

- Non-intercooled Novi 1200 with 3.33 pulley (kisses 13 PSI at 6300-6400 RPM before shifting)
- Cheap meth injection kit spraying at over 4 PSI
- 21* of max WOT ignition timing, 11.4-11.5 AFR

My IATs are making it into the 150*-ish range at the very end of a 1/4 mile pass. I'm guessing the car is putting down ~480 RWHP with a typical peaky centri blower curve. It's trapped 120 in the 1/4 mile a few times at full weight, and usually traps in the 116-118 range.

I'm hoping the IC, in combination with the meth, really drops my IATs. I'm contemplating three routes of action:

1. Leave everything else as is and hope for some power gains due to the colder charge.
2. Add a few * of ignition timing at WOT.
3. Drop a 3.25 pulley on the car.

Recommendations?

I'm thinking I"ll be pushing it with more then 21* of timing - I'd have to think cylinder pressure would start getting too high and I'd be in headgasket-danger-land.

I'm also a bit afraid to throw a smaller pulley on it, for the obvious reasons.

What do you guys think? Leave it alone and see how it does?

 

[skwerl]

Leave it as is. I think your computer is most likely pulling timing when IATs rise. Mine seems to pull timing over 135 degrees. You will most likely see gains by keeping the IAT below 135.

 

[Makdaddy]

Plus some of the turbo guys have had flow issues with the CX Racing air to air intercooler

if its not the bar setup you may have one of them

 

[Stage1]

I had one of their IC,s on my car would not make over 2lbs of boost.. I bought 05stokers procharger IC and got full boost..

 

[06gtmustang]

Low boost is due to not having the correct ic. I would say leave it as is when adding the ic and see how she runs.

 

[05moneypit]

Leave it alone and see what it likes.

Data logs are your friend.

 

[8306gt]

I would say 21 degrees is alot of timing with an intercooler and lower IAT's, much less without one and seeing 150 degree IAT. If it were me and I wasn't planning to build an engine anytime soon, I would add a good intercooler take some timing out of it and enjoy the 100 to 110 degree IAT'S and a little more safety.

 

[Brezick]

I would leave it as is and see how much an effect it has on the temp first.

 

[Swarzkopf]

Leave it as is. I think your computer is most likely pulling timing when IATs rise. Mine seems to pull timing over 135 degrees. You will most likely see gains by keeping the IAT below 135.

I know it is. I've got it set to progressively pull timing as IATs rise.

I guess I'll try the IC as-is without any tune or boost changes first. Fucking thing isn't going to get here until next Thursday now anyway. I'm not exactly thrilled with CX Racing's customer service at this point. Hopefully their product is better.

 

[Department Of Boost]

So I'm throwing a CX Racing air to air intercooler on my setup. Currently, in short my setup is:

- Non-intercooled Novi 1200 with 3.33 pulley (kisses 13 PSI at 6300-6400 RPM before shifting)
- Cheap meth injection kit spraying at over 4 PSI
- 21* of max WOT ignition timing, 11.4-11.5 AFR

My IATs are making it into the 150*-ish range at the very end of a 1/4 mile pass. I'm guessing the car is putting down ~480 RWHP with a typical peaky centri blower curve. It's trapped 120 in the 1/4 mile a few times at full weight, and usually traps in the 116-118 range.

I'm hoping the IC, in combination with the meth, really drops my IATs. I'm contemplating three routes of action:

1. Leave everything else as is and hope for some power gains due to the colder charge.
2. Add a few * of ignition timing at WOT.
3. Drop a 3.25 pulley on the car.

Recommendations?

I'm also a bit afraid to throw a smaller pulley on it, for the obvious reasons.

What do you guys think? Leave it alone and see how it does?

1psi of boost is about 13-14deg F of additional blower discharge temp. So every pound of boost you add, you increase your IAT’s. In a perfect world you want to meet your HP goals with as little boost as possible. Less boost, less heat. Less heat, more power. Easy peasy.

If you are trying for a HP goal it stands to reason that you run as much timing as you can safely run, then add boost. Or don’t add boost if you reach your goals.

I don’t see while on the meth you can’t run more than 21 deg of timing.

I'm thinking I"ll be pushing it with more then 21* of timing - I'd have to think cylinder pressure would start getting too high and I'd be in headgasket-danger-land.

On meth I don’t think you would be in any danger of pushing a gasket out. I've seen claims that meth reduces IAT's between 100-150deg! Running a IC and meth should have your IAT's down so low that the intake will ice up! (joke)

With my old KB setup I was running 19.5psi, 18deg in timing, 93 octane and 160-170IAT’s for 20min at a time on the track. That is flat out abuse.

And keep in mind, your ECU will pull timing if the IAT’s get too high, the ECT’s get too high, it hears the slightest knock, etc. The system is pretty good of taking care of itself. This isn’t 1980’s technology we are dealing with here.

 

[Swarzkopf]

I know. I tune my own stuff. I pretty thoroughly massaged the timing and timing modifier tables to work with the meth injection.

1psi of boost is about 13-14deg F of additional blower discharge temp. So every pound of boost you add, you increase your IAT’s. In a perfect world you want to meet your HP goals with as little boost as possible. Less boost, less heat. Less heat, more power. Easy peasy.

If you are trying for a HP goal it stands to reason that you run as much timing as you can safely run, then add boost. Or don’t add boost if you reach your goals.

I'm looking to gain 1/4 mile performance, not really a specific horsepower number.

The trade off with pulleying down with a centri blower is that every smaller size pulley you run broadens the powerband a noticeable amount, resulting in real gains at the track. It's of course balanced by the accompanying rise in discharge temps.

It's a little different that with a PD blower.

Either way, I'm going to try the IC as-is first and see what happens. I'll have my SCT software at the track with me and may add a little timing depending on how things go. I'm going to wait on ordering the smaller pulley.

Thanks for all the input everyone.

 

[BruceH]

I ran a cx intercooler with my Paxton. Lost about 1-2 psi. It worked great.

 

[TexasBlownV8]

You'll lose 1-2 psi of boost over the piping and intercooler itself, but, your IATs should be much cooler. THEN you use a smaller pulley to recoup the lost boost, and you end up with more power at lower and safer temperatures.
Having IATs a little above ambient is what I missed on my air/air setup.

 

[KrisR]

As the others said, you will need to drop a couple pulley sizes to recoup the boost loss from adding the intercooler. I had a T-trim on my 05 GT for awhile and had a 3.60 pulley with no intercooler at first and saw about 11psi at 6500rpm. Added Vortech air-air IC kit and had to go down to a 3.20 to get the same 11 lbs. Ended up with a 2.87 pulley (still 6-rib with no real belt slip issues) and saw 15lbs at 6500.

 

[Swarzkopf]

We'll see. I'll try it as-is first. If it loses power, I'll add some timing; if that doesn't work, I'll pulley down.

As is usually the case with stuff like this, there is no single 'right' answer as everyones combination is different. I was looking for input and appreciate everyone's feedback. Thanks all.

 

[sportinawoody]

isnt 21 degrees a little much for a stock rod and piston ? seems like thats running on borrowed time

 

[Swarzkopf]

Eh... I don't know. While everyone throws out the '500 RWHP limit' for stock bottom end 3Vs, I tend to think there are other factors at play regarding failure. Like:

- Engine torque (with a Paxton Novi 1200, it's low)
- Boost delivery - boost onset is much more violent with a PD blower or turbo
- Presence of knock - I scan pretty religiously to make sure it isn't knocking

I may be at or near the limit, but I haven't read about nearly as many failures with centri blown 3Vs as I have with PD blower setups, especially at my performance level. I tend to think they're a little safer. Either way, wish me luck.

 

[sportinawoody]

. i just popped my stock block saturday on a 3rd gear run with a whipple at about 25k with the blower on. rod bolt let go. no knock and not running lean and i was at 16 degrees and a rich 11.2 afr making 480 on a mustang dyno

 

[Swarzkopf]

That sucks man. 25K miles is still a pretty decent run. Keep in mind, your Whipple brings boost in a more violent, instant manner then my Paxton and generally produces more torque - so I'm keeping my fingers crossed for now regarding my setup.

Good luck with the rebuild.

 

[one eyed willy]

so im guessing with 21* timing currently you are running 100% meth?

the CX intercoolers are fine, just depends on which one you get, guys have had issues with the in/out on the same side....ive been running a 31x12x4" CX for years with no issues, i have the kind with inlet/outlet on opposite sides.

With the CX intercoolers i see about 120* at the end of a spirited run with my turbo, i run 17* total at WOT. I have a 50/50 kit, but dont normally have it turned on, when i do, it is set for 12-15psi.