Random 3400 specs needed

[bszopi]

Here is some interesting reading for you and your buddy...

http://www.sdsefi.com/techegt.htm

Another site that I checked out said that EGT reading can vary by as much as 100ºF between different cylinders at any one point in time. Therefore, how you can design a header off of EGT readings is beyond me. If you want a range, I'd say somewhere between 1000ºF and 2000ºF.

[qtb33]

hey guys, I am the one who is doing the math for these headers so i though instead of use canada as a relayI'll just joing the board.

Here is the deal. Everything you gentalmen have said is 100% correct.

I was just wondering if anyone has a all motor car that they have observed the EGT. My car all motor runs anywhere from 600F to 1550F, 0-100% throttle respectivily.

I also understand that there are many many thing that may change EGT but a good average for mildly moded cars is a great guesstamite rather than shooting in the dark. Not a must but i was curious, I can alway use my cars data.

Ah port size. I want this b/c I can use it to find the exiting velocity of the gases. Which as you already pointed out changes with rpm, load, A/F ratio and other breathing mods. I can use this to help tune the headers for what ever part of the power band you want.

VE also plays into the exiting velocity. just b/c its a 3400cc dosn't mean its flowing 3400cc's of air, yes this also changes with RPM and lots of other things. However any data the you might know is better than guessing. Once again this can be used to tune the headers to a specific part of the power band.

In the end none of it is a huge deal due to the fact that you can only get tubing in 1/8th - in. increments at best. I just thought it would interesting to look at how all the elements (velocity, pressure, mass flow rate,) all change with rpm and tube diameter. These number just help correct the numbers to more of a actual rather than theory which we all know very seldom is how thing really workout.

p.s.~ SDS is good stuff, I'm using the SDS-EIC to control 2 X 480 cc/min injectors.