Full EGR delete question

[BlackJack]

So, since you brought that subject up Ben, what kind of cat and muffler combo would you recommend in a single exhaust that won't restrict the flow if you're trying to push over 600hp?

[kwhauck]

don't forget primary size for custom headers and exhaust size into the question....

[bkathsalero]

I was diagnosing a plugged cat, then fell into a side motor r&r job so between that and work didn't have time to re-install it. Had it off for a whole work week

[WhiteV6]

Magnaflow have some spun cats. I may use one for a resonator, but for 600hp, I am thinking 3" min diameter. Turbos love larger exhaust side tubing but I am not sure 3.5 or 4" would be necessary. On the primary side, I would guess about 1 5/8" still for velocity but then again, 100hp per hole is a lot of flow. 1 3/4 might prove better at 4000+ and making big numbers.

Mufflers however, no idea. I go for sound and like flowmaster. I know they aren't the best flowing design but the best flowing are also louder. Might need to compromise there.

[-Alero-]

well hey blackjack if you want to get that critical with IAT wouldnt the IAT position be even more critical? if the IAT is in its stockish area, with heat soak, heat expands and spreads through the aluminum manifolds, so in "theroy" as you said, heat could just eventually start soaking the intake plumbing where the IAT is, right? in my opinion thats what happens in a stock situation.

but of course you can relocate the IAT all the way up to the front bumper if you wanted, its still a method for reading the emperature, just in a cooler spot. so i agree with you completly on how big a factor that all is.

also what i forgot to mention was, running a richer a/f would lead to lower combustion temperatures would it not?

[BlackJack]

Originally Posted by -Alero-

well hey blackjack if you want to get that critical with IAT wouldnt the IAT position be even more critical? if the IAT is in its stockish area, with heat soak, heat expands and spreads through the aluminum manifolds, so in "theroy" as you said, heat could just eventually start soaking the intake plumbing where the IAT is, right? in my opinion thats what happens in a stock situation.

but of course you can relocate the IAT all the way up to the front bumper if you wanted, its still a method for reading the emperature, just in a cooler spot. so i agree with you completly on how big a factor that all is.

also what i forgot to mention was, running a richer a/f would lead to lower combustion temperatures would it not?

Heat soak in a stock intake system isn't as much of an issue, since the majority of the plumbing up to the TB is plastic/rubber compound. Where you would experience more heat soak in the primary would be for those running metal CAI/WAI's.

Running a little richer does run a little cooler, but too much will also get hotter again, and eventually it will foul the plugs faster as well, not to mention the excess carbon buildup in the combustion chamber. Case in point, when I was working on getting tuned and was set too rich, you should have seen the flames shooting out of my exhaust pipe, since there was nothing to suppress it.