More boost the answer??

[The patriot]

I installed my 370's about 2 months ago. I'm VERY happy with them, but I do have one question/concern.

While on the open highway at high speed, I get EGT's up to 1100 post turbo. This seems a little high to me. It's only high when I'm up around 85-90 mph and if I hold it to the floor. By the time I reach 95, it's at 1100.

Granted, this is not an every day occurance, but I havent put it under a substantial load since I've installed them. This is my real concern.

Driving around town, I really believe they give me a lower EGT. Also, when I go to park, theyre almost always under 300. My "old" ones usually required that I wait a minute.

Again, I'm real happy with them, just want to know if something can be done about this (more boost somehow?) or is this "normal".

Eric

PS I did notice that I had a few more pounds boost after the installation. Maybe a few more would help?

 

[Roger rodbolt]

Cool CFM = lower EGT's

Eric,



You're on the right track, more boost will help egt's until the intake air is too hot due to turbo overspeed... etc. Our 12 valve engines need more air flow particularly at higher rpm's. Adjusting the wastegate or installing an aftermarkert "elbow" in the wastegate actuator line will increase boost with increased fueling.



If your pump plate is not moved forward and you don't intend to increase fueling in the future, I'd just move the egt probe to the manifold, adjust the wastegate to max at 32lbs, tighten all intake/intercooler connections and probably pressure test the system, clean a/c condensor/intercooler/radiator of bugs or blocked airflow (big driving lights in the bumper openings) or internal oil, make sure that you are at least using a minimun of a clean stock airfilter (without the foam bottom)and remove the boot between airbox and fender. I'd also check the timing and consider 15 to 16 degrees if you are staying in this level of tune.



Four inch exhaust, ATS manifold, HX40 turbo, higher flow airfilters will be in your future if you put a big plate in your 215 pump. I recently purchased a core '97 5speed engine from a salvage yard. It has a rod blown through both sides of the block . I disassembled it and believe that it was stock except for injectors. Every piston was scored from excess egt heat and it appears that the increased friction/piston gall caused a rod bolt to break and destroyed the engine. I salvaged the big P pump, front cover, gears, etc. but the camshaft was broken in three places and crankshaft ruined. The head is intact but probably cracked from heat, just haven't take the time to disassemble it and check.



To a fellow NRA Lifer: Low egts are cool

 

[moparguy]

Eric, I really think you could benefit from a BHAF. Either the Fleetguard AH19037, or NAPA 2790. I've got about 5,000 miles on the NAPA filter with no noticed downside. Just lower EGT's.

After a 1200 mile, 19hour run from Montrose Colorado to Sheridan Arkansas without a shutdown, and running boost numbers of 10 to 20lbs. at about 2500 rpm for the 19 hours, I see no signs of heat discoloration or any other heat effects on the filter from the near proximity of the turbo.



I think a good low buck project would be the BHAF and a 16cm2 turbo housing, could do this for about $175. 00 or so (Piers has

the housing on sale for $125).



Of course, there are many other options if the buget is a bit fatter.



Good luck, Ronnie

 

[Forrest]

Eric, what kind of boost are you running when you measure 1100 degrees post turbo?

 

[The patriot]

Originally posted by Forrest

Eric, what kind of boost are you running when you measure 1100 degrees post turbo?

Not sure. It was night, and not many (actually none) were going as fast as I was. Kinda had to watch the other vehicles.

I'd guess around 26-27 psi, judging from what I've seen it run at lower speeds.

Eric

 

[Cooker]

I just wanted to stress that 1100 post turbo is very high. It has been my personal expereince that pre and post turbo differ considerably more than 300 degrees. Be careful about getting up over 900 for any period of time.



I agree with the others. I think some of the best mods for you are the BHAF and 16cm exhaust housing. This combo should be good for a minimum 150* drop in EGT's. It will likely be closer to 200*



JMHO,

Ryan

 

[Roger rodbolt]

I agree that a 16cm housing and BHAF are great upgrades, however in Eric's signature line he indicates that his engine is stock except for the injectors. With out pump mod's the 370 marine injectors are a modest fueling increase. 1100 degree post turbo during a short high speed run are, in my opinion, abnormally high for this setup. I hope that we can solve his egt's now because we all know how addictive BOMBing can be

.

 

[The patriot]

Originally posted by Roger rodbolt

1100 degree post turbo during a short high speed run are, in my opinion, abnormally high for this setup.

Yes. I'm just trying to picture what it would be like with my camper attached.

I have a new stock air filter, and the restriction gauge barely moves. I keep all the bugs out of the intercooler fins too.

I really like the way it runs with the injectors.

Is there any way I could make a home made exhaust elbow to experiment with boost levels? Or can it only be adjusted by the vacuum pot screw(proper teminology?) to the waste gate?

Eric

PS You guys talking about cracked heads are freakin me out!!

 

[Forrest]

Eric,



The reason I asked was that when I was running 32psi @ 950 degrees, post turbo, I moved the probe pre-turbo & it was 1500+



I always thought I was safe, so I ran that a # of times.

 

[JGK]

As a comparison...

Eric,



Our trucks are similar, though I've added a few extra mods. For comparison: I finally hit 1300 degrees pre-turbo for the first time the other day - WOT, empty up a 6% grade. 95 MPH, just under 36 lbs boost, 65 degrees outside temp, about 3000 ft. ASL.



There may be other things involved, but I really think a 4" exhaust and a BHAF will help.



FWIW,

Jay

 

[Swamp Donkey]

I can burry my 1500 degree pyro in about 3-4 seconds. It goes way past the 1500 degree mark then bottoms out on a screw! This is at 38 lbs boost. So more boost does not cure egt's IMHO.

 

[cumminsgetme]

I'm running 45 pounds of boost and still bury my pyro guage. 1100 deg post turbo is way high for your kind of modifications. What kind of temperatures could you get it to before you installed the 370's. Seems like there is a problem lurking somewhere causing these high temps, but became more noticeable after installing the 370's due to the extremely high temps.

 

[The patriot]

Temp before the injectors was 900. This was doing the same thing. Find an open stretch of road, and floor it until it de-fuels.

I cant get the egt's this high doing anything else. Only in high gear floored for a good long time.

I'd get the 16cm2 housing tomorrow if you didnt have to screw with the exhaust system. This is a daily driver. I cant tie it up.

Also:

What is a BHAF. I know what it stands for, but what's involved with the mod. Can I use my stock filter housing? If not, where can this be purchased?

Dummy it up a bit guys. Pictures help too!

Eric

 

[Roger rodbolt]

Not all boost is the same?

Swamp Donkey,

What turbo and housing are you running? Timing? I suspect that a #6 plate on your setup may be fueling the engine while on piston is on the downstroke. If your are running a stock turbo... it's on overspeed-feeding hot air on the intake side which equals higher egts.



Serious fueling requires a lot of air and the cooler the better. 38 lbs for boost out of a H2E or twin setup will run cooler, if you're injecting the fuel at the proper time. I've not had problems with the HX40 other then 12 valve engines exceed the cfm if heavily fueled. Just trying to help maintain your driving pleasure---by keeping the hammer down!



Cumminsgetme,



Have you experimented with timing on your setup? Alot of the folks here are running 18 or 19 degrees but I've been reluctant to go there. (I've seen 21 on the 160hp pumps) Hoping that you could compare power, smoke and egt differences in say 16 and 19 degree timing. Thanks

 

[Swamp Donkey]

Re: Not all boost is the same?

Originally posted by Roger rodbolt

Swamp Donkey,

What turbo and housing are you running? Timing? I suspect that a #6 plate on your setup may be fueling the engine while on piston is on the downstroke. If your are running a stock turbo... it's on overspeed-feeding hot air on the intake side which equals higher egts.



Serious fueling requires a lot of air and the cooler the better. 38 lbs for boost out of a H2E or twin setup will run cooler, if you're injecting the fuel at the proper time. I've not had problems with the HX40 other then 12 valve engines exceed the cfm if heavily fueled. Just trying to help maintain your driving pleasure---by keeping the hammer down!

I have the stock turbo housing. Piers said he was going to Holset next week, so I am going to wait for a while and see what he comes up with! As for the timing, it is also stock for a 98 12v auto. I almost forgot about the timing issue. I always get caught up in the 4 inch exhaust, BHAF, and turbo housing ways of reducing egt's that the timing gets overlooked. Forrest e-mailed me and mentioned the timing as well so I did some searches on it and will get the timing adjusted when I get near a competent shop. Being way out in the sticks has its disadvantages! With the help of the TDR, I'll get my truck running like a scared hyenna!

 

[cumminsgetme]

Roger,

I have been fighting a real agressive popping at high rpm. I went to 19 deg hoping this would push the popping higher in the rpm range. It delayed the poping by 2-300 rpm, so it did help. It scares me a little running at 19 deg due to cylinder pressures getting too high. It seemed to have a little more pep on the top end, but it's hard to tell just by the seat of the pants. Smoke is always thick at full throttle but I didn't really see much difference going from 16-19. EGT's dropped about 50 deg... so it helped a little but not much. Fuel mileage has also gone down a hair. I went to 19 simply for experimentation and soon will drop back to 16 (where I was previously at). I think that all around efficiency is best around 15-16 deg.

 

[Roger rodbolt]

Thanks for the info.

Cumminsgetme,



I appreciate your feedback on the timing. Seems to me that there are a lot of variables in the P pump, different cam profiles and etc. It is interesting that your popping declined though. Wish I could offer some help but would be only guessing and anyone can do that. Good luck and let us know when you find the culprit. We all benefit

 

[cumminsgetme]

Roger,

I have settled with the fact that my 175 pump is simply too small and is causing the popping. The cam profile in the smaller pumps don't allow for enough fill time causing the pump to play catch-up under full throttle. Some people have this problem with the smaller pump and others don't. I think that those who don't may not be as heavily fueled or possibly have a less agressive driving style. My friend swore up and down that his truck didn't pop... . well, it did (his truck is very similar to mine and equally fueled). He said that he had never noticed it popping until I pointed it out! I guess I'll find out if the pump is the culprit when I swap to the big pump.

 

[Strick-9]

Gosh, I wonder who that idiot was. In my defense though, my truck shouldn't be at 3200 RPM with an auto unless I have the shift points wrong.



I've fixed MY popping noise though. It'll NEVER pop again.



hehe.



Just rubbing it in a little more Cord.



-Chris

 

[Roger rodbolt]

Cumminsgetme,



The big pump is sure to please . As you probably know, some of the early injector lines were restricted during manufacture. Using a numbered drill bit you can check and open up the flared ends when changing the pump. With the 215 pump, your injectors will appreciate the newly found flow . Dual turbos soon to follow!