High EGT's under hard acceleration

KPSquared · Jul 3, 2011

I have just recently got my truck back together and running well. The only issue I seem to have now is if I get on the throttle hard, my EGT's climb like a rocket until I let off. I could bury my gauge past the 1500 mark if I didn't let off.

I'm pretty new to all of this stuff, but I was under the impression that if everything is running right, it shouldn't do that. I was trying to see what my HPOP was putting out so I was trying to do some 80 - 140 km/h runs and I can't. It starts to get WAY to hot before I get anywhere close to speed. So, this is within 20 seconds under WOT.

2001 7.3, Cass Stage one singles, DP F6 with 80 Economy, 3.5/4" Magnaflow, 6637.

I just changed the up-pipe gaskets because they were leaking thinking that would solve the problem. It did help, but still not good.

I have heard that DP's tunes run a little hotter, but I didn't think it would be quite like this.

Anyone?

CSIPSD · Jul 3, 2011

Stock turbo still?

Boost levels?

KPSquared · Jul 3, 2011

Stock turbo. With that 80 Economy tune under WOT, I'm peaking at about 24 psi. maybe 22.

I think I may have a leaky IC boot. I'm gonna check that next. Will that cause the EGT's to spike like that?

Tom S · Jul 3, 2011

Yes it could. A good HPOP also helps.

CSIPSD · Jul 3, 2011

Stage 1's are only 160cc, just a slight bump from stock, you should not be having a huge jump.

I would also expect to see 28-30psi at WOT with stage 1's and a stock turbo.

Check your wastegate, tighten it a few turns. Also, as you mentioned, check all your IC boots and also the Y pipe boots, very common to have boost leaks at the intake manifolds.

CSIPSD · Jul 3, 2011

Tom S said:
Yes it could. A good HPOP also helps.

Going from AD splits to stage 1 singles he should be using the same or less HPO... I dont think its a pump issues, his boost is very low.

Whytry · Jul 3, 2011

Yea boost doesn't seem right at all. Do you have custom tunes on that dp?

Tom S · Jul 3, 2011

I agree that a leak is the first area of concern.

KPSquared · Jul 5, 2011

I'll get my pressure tester built and see what's up. Won't this truck de-fuel at 28 or 30 psi? I don't have a boost fooler. Or do the tunes compensate for that?

I don't remember the numbers, but the HPOP is working good.

Trying to find a local source for boots. Think I found a place but I'm on holidays so I gotta wait till I get home next week. Want something similar to diesel sites boots. If I can't find anything here, I'll just order a set. I live in the heart of oil country and there are a number of hose shops. One of them just might have what I'm looking for.

CSIPSD · Jul 5, 2011

If you dont have a boost fooler or regulator then the factory programing will begin to defuel at 22-25psi... However you would not see high egt's with that...

Get this...

http://shop.strictlydiesel.com/store.php/products/Overboost

and install.

But I am still betting on a boost leak somewhere.

genie144 · Jul 5, 2011

CSIPSD said:
If you dont have a boost fooler or regulator then the factory programing will begin to defuel at 22-25psi... However you would not see high egt's with that...

Get this...

http://shop.strictlydiesel.com/store.php/products/Overboost

and install.

But I am still betting on a boost leak somewhere.

I am not sure on DP's tuning but some tuners bypass the defuel in tuning without requiring a boost fooler. I would check with Jody before buying a boost fooler. Also you can make a boost fooler REALLY simply... It is an air regulator with a gauge and 1/4" line to the MAP. Set the regulator from your garage compressor and be done. Much less than $60+shipping. Strictly Diesel (formerly ITP) does make some quality parts though. Not knocking it at all.

Sam

Arisley · Jul 6, 2011

Tony's tunes defeat the overboost defueling. You still get an overboost CEL though.

KPSquared · Jul 6, 2011

So, Tonys tunes do, but what about Jody's?

I was under the impression you couldn't just build an overboost regulator. Something about calibration or something. I read something on DIesel Sites boost fooler page.

Charles · Jul 6, 2011

My 550 runs the 38R with some 300/100's and with no boost fooler it never defuels nor sets a SES because the program has that turned off.

I'll have to thank Matt for that. He pointed me toward a couple parameters that needed a little adjustment.

CSIPSD · Jul 6, 2011

Well I would love to remove that little jem... one less thing to have under the hood.

KPSquared · Jul 6, 2011

Ok... So... Matts and Tonys tunes do. What about Jody's?

genie144 · Jul 6, 2011

As far as boost foolers (this is my understanding)... You just set the regulator to 20-23psi on your home compressor then install with 1/4" between MAP.

There are 2 issues with the boost foolers that utilize a regulator. The first is maintaining the setting of the regulator - this is user error or crappy regulator. Strictly Diesel solved that by using a regulator that is preset and can't be changed - takes the user out of it. Strictly claims there's is better.

The second issue is accuracy. Most shop regulators are not as accurate at low pressures so your MAP won't see actual boost levels at low boost... So at <15psi your MAP will likely see a different boost number than what the engine is. This would affect the fueling, however most tuners that still require a boost fooler can account for that in the tuning... Also using a regulator for the pressure range we are talking about would also help. Diesel Site has overcome this "issue" using a pressure relief valve and manifold. They of course claim their's is better.

I don't have experience with either directly, but I really don't think either is better than the next or just a good regulator. They all accomplish the same goal through different means.

Sam