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88_pacifica
07-01-2007, 09:35 AM
Ok guys, I bought the Prosport Exh temp gauge and also 30# Boost gauge, have it all hooked up and they're both working like a champ. However, I have a question regarding EGT's for my application currently.

Basic 2.5, +.020 over stock rebuild except chrome-moly's, BS's removed. I have a mildly ported intake and exhaust manifold. Garrett T2, small 2.25 ported SV for now(will change soon to 2.5) and NOT IC'ed yet(coming soon). I have the stock T2 injectors, stock FP regulator, stock fuel pump(55 psi verified w gauge) and stock 88 exhaust and DP with an auto trans. Everything appears to be running well.

However these are my temps:
Idle- 12-1300*
Part throttle(no boost)- 13-1400*
Part boost- 14-1550*
Full Boost- 1550-1650*

Now, my questions are these regarding those temps. This a relatively speaking "stock setup" right now and I plan to stay within the normal boost #'s for now. but, are these safe temps. I have read that people are at 1400 in part boost and I'm slightly higher. What is the "high end" figure for these motors bone stock? Am I safe for now? I have considered +20's but I don't want to have crappy gas milage and the need for an adj fpr and all that.

When I IC it, will exh temps drop considerably? I can't see it doing that, but I guess it "could" since it's "somewhat" cooler. Also, when I open up my exhaust will it drop as well? Again, I guess it could, but I think that's doubtful. Am I really on the "ragged edge" of safety? My big concern is a "safe reliable car until I re-supply my funds to keep adding on here. SO, what are your thoughts guys? I will add more as I think of more. Thanks all...

Nate

88_pacifica
07-01-2007, 08:55 PM
Bump... Anyone with experience in this area?

Frank
07-01-2007, 08:58 PM
I think they are two high.

Where did you put the sensor?

Tony Hanna
07-01-2007, 09:04 PM
^+1
Could be due to ignition timing though. What's your base timing set at?

Frank
07-01-2007, 09:07 PM
Very good call... something we all forget.

88_pacifica
07-01-2007, 09:33 PM
stock 12* and sensor is in the #4 runner. Should I advance the timing a few degree's? Get it to "detonate" a little sooner?

Tony Hanna
07-01-2007, 10:05 PM
stock 12* and sensor is in the #4 runner. Should I advance the timing a few degree's? Get it to "detonate" a little sooner?

I wouldn't. The fact that your EGT's are that high with stock timing (retarding timing increases egt's) leads me to believe that it's a fueling issue. Too lean or way too rich will cause an increase in egt's. Without a way to monitor AFR, you're prettymuch stuck reading the plugs to figure out what's going on.

Try this: Buy a new set of plugs and install them. Find a nice stretch of road with a wide shoulder where you can safely make a full boost run. Right at the point where you're ready to lift off of the throttle, shut the key off, throw it in neutral, and coast to a stop on the shoulder. Now let the engine cool a bit, pull the plugs and have a look. Brown or black on the porcelin indicates a rich condition, white indicates lean, and a light tan is just right. Speckles of carbon or aluminum on a white insulator indicates detonation as a result of being excessively lean.

If you have a digital camera, take some pics of the plugs, and post them up here. We'll try to help you figure out what's going on.

88_pacifica
07-01-2007, 10:28 PM
Thanks Tony... :thumb: I'll give that a shot on the 4th since I have that day off...

Tony Hanna
07-01-2007, 10:49 PM
You're welcome.
Let us know what you figure out.

moparman76_69
07-02-2007, 01:57 AM
using that as a guide and going by the plugs when I pulled them the other day you're rich.

Tony Hanna
07-02-2007, 03:26 AM
using that as a guide and going by the plugs when I pulled them the other day you're rich.

Problem is, you really need to read a new set that's had the engine shut down immediately after a full boost run, or you'll be seeing the effects of idle and part throttle which can be misleading (could be running rich off boost but lean on boost).

guyd_15
07-02-2007, 06:33 AM
It's easier to read the plugs if you use 104+ octane booster (Gus Mahon idea) add a can when you have just a few gallons of gas in the tank. It will give the plugs a reddish color, unleaded gas doesn't color the plugs much.

Guy

Stratman
07-02-2007, 01:34 PM
That really shows how equal the injectors are firing between the cylinders and the dark red seems to make signs of detonation harder to see.

shadow88
07-02-2007, 08:30 PM
Aside from the ignition timing point which was a great point, another missed question was the boost pressure. If you added a 30 psi boost gague, it's probably because you're running more boost than the computer can make adjustments for.

Get to that IC install.

What's the boost pressure during those WOT runs?

puppet
07-02-2007, 08:55 PM
He said that he was running pretty much stock boost levels.

Tony's suggestion is right on. At least you can be more sure if your rich or lean.
All things being equal you seem to be 100-200* higher than a "normal" EGT range. I'd be willing to bet that it's because you're not IC'ed. Under load ... good A/F ratios included, you can expect higher EGT's. That's just how it is.
You might consider advancing the ignition 1-2* at this point to cool him down some. This will shift some of the heat to your block (read coolant/oil).

TurboJerry
07-02-2007, 10:00 PM
I would try to retard the ignition timing *first* 2 degrees to actually see if it lowers the egt's. I always noticed that egt is a bell shaped curve, so I try to find out which side of the bell I'm on *first* before making more changes. Advancing the timing may cause more knock, and the egt's will shoot up even higher.....

88_pacifica
07-02-2007, 10:49 PM
He said that he was running pretty much stock boost levels.

Tony's suggestion is right on. At least you can be more sure if your rich or lean.
All things being equal you seem to be 100-200* higher than a "normal" EGT range. I'd be willing to bet that it's because you're not IC'ed. Under load ... good A/F ratios included, you can expect higher EGT's. That's just how it is.
You might consider advancing the ignition 1-2* at this point to cool him down some. This will shift some of the heat to your block (read coolant/oil).

Good point... I think that at stoich it is actually a slight bit warmer than what we typically feel "comfortable" at. This was kind of my original conclusion before I posted, but being that it's all "stock" settings currently for the most part, I wanted to post up to be sure. I will eventually like to get a WB as a NB is very limiting really. I am thinking +20's with an adjustable FPR are going to be the magic touch here. Especially since I am not really sure that I will be "happy" long term with factory boost levels... but I have to be for now... :D

Tony Hanna
07-02-2007, 11:46 PM
I don't know. Your part throttle/boost temps look reasonable to me. It's the full boost temps that are worrisome. Remember, the stock cal runs leaner at part throttle than at full throttle. I've seen the Sundance (even with an intercooler) get pretty freakin' hot on the interstate pulling a hill at part throttle in boost. At full throttle, it's a different story though. Out of curiosity, what cal are you running? If you're running a stock TI cal, then I bet the port work and Garrett have you flowing more air at full throttle than it's designed to support. That would account for your higher full throttle temps.

Just a thought, but why not rig up a quicky water/alcohol system for it until you get your IC on?

88_pacifica
07-03-2007, 08:15 AM
Yep, Stock 89 T1 2.5 cal. I kinda figured the same thing actually. A port and different turbo is likely the source of the higher temps at full boost. I had actually considered alky and I was thinking that might be in the very near future. I think that it is probably a little cost prohibitive I would imagine, but I really have no idea what it would cost since I haven't researched it in depth. I guess thatif I want to get serious I should get a cal, bigger injectors, alky, yadda, yadda, yadda... But I can't decide how far I want to go. remember, this has a 100K mile auto trans so I can't get too crazy. I am not 16, power-braking the piss out of it, but I don't need to pick up an input shaft or carrier parts either when in full boost. So I am limited at this point. I need reliability and "fair" boost, not 22#'s and unreal speed. I have a Grand National for that. :D I just want the smalll V8 power with 4 cyl sipping when I'm not boosting. I've already thrown over 3 grand at this thing so I want reliability ALOT!I can't make this my everlasting project. I just noticed on Sunday the front crank seal blew on this 20 mile fresh rebuild.... ARGGHHH!!! Now I have to find a sprocket puller... and do it ALL AGAIN!!!

Dusty_Duster
07-03-2007, 01:35 PM
I think you should intercool it before you think of doing anything else.

88_pacifica
07-03-2007, 01:59 PM
I think you should intercool it before you think of doing anything else.

I agree.. I am going to find the biggest one I can suppport in front of the daytona AC condenser. I have already made the "holes" to run the piping through the passenger side to keep the AC and auto radiator. I have 2 "smaller" Saab ones that are about the size of the factory T2 ones, but I don't think I'm going to use those. Also, I bought a GN one that is pretty efficient, but I changed my mind about those too. I'm going ot sell the Saab ones and prob get one that is as big as I can "easily" fit behind the cowl. Now, I just need to figure out which one I should get....

I have a factory Volvo BOV that I'm prob not going to use either, but I'll prob sell it too. That reminds me... I should borrow a digi camera to sell those on here... but I figure the Saab's are only worth about $30-40 and the Volvo BOV about $30 too.... Theya re just OEM and even though they work well... nobody will prob want them...

Dusty_Duster
07-05-2007, 09:04 AM
I agree.. I am going to find the biggest one I can suppport in front of the daytona AC condenser. I have already made the "holes" to run the piping through the passenger side to keep the AC and auto radiator. ...

Ditch the A/C. Real men don't have A/C in their Turbo Dodges. :eyebrows: :lol:

88_pacifica
07-05-2007, 09:48 AM
Ditch the A/C. Real men don't have A/C in their Turbo Dodges. :eyebrows: :lol:

Ha.. yeah well, I didn't drink the kool-aid so... "I don't think so!" That's the whole reason I bought a pacifica. I wanted to have ALL the options, ESPECIALLY AC! If I just wanted to go fast, I'd get an omni, gutted to hell and back and shoot for 600+ horsey's, but, I think that I am going to use the TD for what it was designed for in this case... an econobox. ;) :thumb:

overlordsshadow
07-05-2007, 11:06 AM
Not sure what a safe temp is but my new cylinder head is taost from 1475 temps. Melted around the fire rings then blew them back and just pooched the gasket hard. Then the combustion pumped out all my coolant, good thing i was watching the gauges closly

88_pacifica
07-05-2007, 11:13 AM
Not sure what a safe temp is but my new cylinder head is taost from 1475 temps. Melted around the fire rings then blew them back and just pooched the gasket hard. Then the combustion pumped out all my coolant, good thing i was watching the gauges closly

Yeah... I saw your post about that. That totally sucks too. I agree with the idea that the percentage of "alloy" was off though, too much straight aluminum. I think you had that Mexican head right? I would be seeing what they have to say about the casting process and metallurgy contents. I have seen no negative results yet, but I am not driving it for etended periods though either, nor am I hittinig "full boost." Part of the reasion for this is because it's a fresh rebuild though too.

overlordsshadow
07-05-2007, 11:17 AM
Well I'm going to try my old cyl head with a cometic and new mp bolts. We'll se how it goes.

88_pacifica
07-05-2007, 11:28 AM
cometic....? plane that head.... get it smoother than glass. :D or else it will go. Cometic's need glass smooth.

overlordsshadow
07-05-2007, 11:50 AM
Okay. What are these cometics made of that make them reusable?

88_pacifica
07-05-2007, 12:14 PM
AFM is a chemically blown, compounded nitrile synthetic rubber, bonded to an aluminum core with temperature resistance of over 2500 F. AFM material does not require gasket sealers or silicone bead. Re-torque is NOT required.

Cometic Multi-Layer Steel (MLS) head gaskets go on dry because they are coated with a sealant. Each MLS head gasket is coated with a .001" thick viton rubber that is bonded to the outer stainless steel layers. Adding an additional sealer can hinder the performance of an MLS head gasket.

They go on dry... and.... they have a "rebound" action even after it is "released" from it's original compression.

BadAssPerformance
07-05-2007, 01:23 PM
cometic....? plane that head.... get it smoother than glass. :D or else it will go. Cometic's need glass smooth.

Need flat, not necessarily 'glass smooth' tho...

Reaper1
07-06-2007, 10:05 PM
I'd suggest getting the MOPAR headgasket sealant spray...even though they say it doesn't need it. Ask a Neon guy what happens to their MLS if they don't use that sealant...no, or very little compression. Seen it happen.

BadAssPerformance
07-06-2007, 11:25 PM
In the neon mopar gasket viton coated? Didnt coat my Cometic, no sealing issues whatsoever.

Reaper1
07-07-2007, 03:02 PM
I honestly don't know the answer to that question.

Speedeuphoria
07-07-2007, 11:28 PM
The answer is no, the neon mls is not coated and copper spray is required, Cometic needs none as stated, well at least for the 1st install, may be helpfull for the 2nd or 3rd install's

WickedShelby88
07-13-2007, 01:57 AM
I will second that. The gasket will visually show the difference in color of the surface as well. You can tell a cometic from a Mopar MLS 10 feet away.

moparzrule
07-14-2007, 06:45 AM
Back to the EGT's, LOL.
First intercool that sucker. Then turn the fuel pressure up to 60 PSI static until you get a different cal on there. Running stock boost, 60 PSI static won't hurt a thing unless you have a weak fuel pump to begin with. The 5 PSI increase should take care of your higher EGT's due to porting.