EGT temps vs. RPM vs. time?

[lametec]

When looking at an EGT gauge during, let's say, a run through 4th gear, what should I expect to see?

Will it level out around a certain temp or keep rising with RPM?

Anyone have a chart from a dyno run or similar?

Thanks!

[4sfed4]

Its very tough to generalize on how EGTs temps vary with RPM as there are so many variables.

Typically (if the fueling is setup correctly), a "normal" car will show EGTs increasing with RPM. Mine will typically peak out at max rpm.

[howard]

I can only tell you my answer based on my "other" car. During a quarter mile run, the more RPM's, the higher the EGT. However, it only goes up about 100-150 degrees between 4000 and 5800.

Howard

[lametec]

Ok, that sounds like what I saw, then.

Started in 4th gear at about 1300° (around 2500 rpm). By 5700 rpm or so it was up to 1600°.

So then, when you use the EGT to tune the car, do you tune for the temp at max rpm? Example; 1600° at 6000 rpm?

Sounds like an EGT gauge isn't so great for tuning, but more for safety.

[John B]

For me the egt readings are the most useful for tuning. I have never been able to get my fuel/air meter readings to be reliable. You will find that retarding ignition will increase egt, advancing the cam will reduce egt, in addition to the obvious fuel/air ratio changes. But once you are aware of these factors you can use your egt to tune. Just change only one thing at a time. I would suggest though that 1600 may be a tad hot unless you're using forged pistons, but there are many successful racers that will disagree ( I like 1500 for my setup and I'm happy to trade a bit of power for reliability).

yea i was gonna say 1600 seems fairly higjh..arnt they sposta only be like 1550 or so?

[lametec]

I know 1600° is considered high by some (most?) people. The 1600° was only for a couple seconds, though, as it only went that high right before shifting.

This is on a 2.2 with stock pistons and 20psi.

[glhsken]

Per, I saw the exact same redings as you did with stock pistons.. Climbed to 1600 right at the end of the dyno pull. Mine was due to too little timing.. The car was FULL of fuel (less than 10:1 on the wideband)