Lowering EGT's

[Turbo84Voyager]

Hi,

I finially got my caravan back on the road with the new engine. The EGT's appear to be high. When cruising they are around 1500. When I was climbing a hill with little to no boost, it started climbing it hit about 1610. The engine is new so I dont want to beat it too much under boost. The engine seems to be running a little rich at idle. The engine is a 2.5 forged wiseco's, G-head, TU header T3/T4 hybrid, 40+ injectors with AFPR with static set to 30 psi. The engine has a granger set to 7 psi for break in and until I get the intercooler in. The exhaust is 2 1/2 with no cat and Dual pipes after the free flow muffler. The EGT probe is in the header right before the turbo flange. The van seems to be a little rich at idle. The idle is a little rough until it warms up and the Dawes A/F is pretty well stuck blue ( rich ) until it warms up, this is why I dont understand the high EGT's. Has anyone ever experienced this before? Does anyone here use rising rate regulators? I was thinking with one i can lower my static but increase my fuel under boost.. What do you think? I have a very similar setup in my shadow minus the g-head and header and the EGT's appear to be lower.

Any info would be appreceiated

Thanks
Justin
84 Voyager LE 2.5 Intercooled Turbo 5-spd
91 Shadow "CSX Clone" Convertible 2.5 Turbo
89 Caravan ES 2.5 Turbo

[risen]

Try advancing your timing a little. I've had timing that was too far retarded cause high egt's more than once. If your a/f's are fine then this is usually the culprit.

[Turbo84Voyager]

Can an overly rich mixture increase the EGT's??

[risen]

Quote:

Originally Posted by Turbo84Voyager Can an overly rich mixture increase the EGT's??

I suppose it's possible if for some reason there's O2 left in the exhaust stream to burn, however it has been my experience that retarded timing is the culprit of high EGT's more often than not. My guess is that if you don't have any additional oxygen to burn in the exhaust stream (rich on all cyl's, and no leaks), it's more likely that the raw fuel is just being spewed out and not burning in the exhaust. Also, it's usually easier to check/set the timing than it is to go and mess with the mixture.

[jim34]

Egt's will be much higher with the probe mounted at the flange you will have to find somone who has done it this way to help you with data. I also agree with risen the timiing makes a big difference.
too rich will cause lower temps and too lean will give higher, but detonation also can cause lower egt's.
Advanced timing gives lower egt's, retard gives higher.

[xrattiracer]

I wouldnt get terribly concerned about somewhat high egt at cruise conditions, but if it stays high under boost thats a problem.

[mopar2ya]

Turn your FP back up to 50-55 psi and I bet you'll be just fine. I see you dont have a cal in it. If not you might consider one. Since you are running +40s if you are doing this on a stock ECU it will be rich expecially at idle even with FP turned down, but at speed and under boost the reduced FP will cause you to run lean.