SPFI EA82, Delta 260 cams... what exhaust?

[Syonyk]

About to order myself a set of Delta cams to throw in my Loyale (EA82 SPFI). It's a daily driver, but I do enjoy autocrossing it and throwing it about on gravel/snow, and a bit more power up high would be beautiful.

 

I've also found an exhaust shop that will do carry out work.

 

One thing I've heard repeatedly is that for the cams to really shine, you need to upgrade the exhaust system slightly.

 

What size pipe should I be looking at for the Y-pipe and then the main run back? I'd like to get rid of the cats, put a glasspack in place of the main resonator, and then either a glasspack on the back or a stock-ish muffler.

 

Also, has anyone dyno'd an EA82 before/after the cams? I'm curious as to how much power I'll gain up high.

 

Thanks!

 

-=Russ=-

[idosubaru]

they have more than one style of EA82 cam available, which one? hopefully not the "track only" version, it's brutal. adjusting your ignition and playing with fuel grades might help. from memory the dyno shows and ER27 can get 7hp just by advancing the timing and running higher octane. might be worth something for autocross

 

slightly larger pipe and replacing the stock muffler from an XT6 helps some, but replacing the converter with straight pipe or a high flow converter did not help at all (i've done both on an XT6). can't imagine a smaller engine being much different. i'm not saying it's a bad idea but if everything is working properly replacing the cat might not be worth much to you.

[Syonyk]

Hm.

 

The grinds they have are "mild street (260 degree)" and "hot street (272 degree)" - I'm getting the mild street one.

 

I may try taking the muffler off and see how much of a difference there is. I was assuming the stock cats were a bit restrictive, but that's coming from the RX-7 world, where pulling the cats out is worth 10-15hp on a NA.

 

-=Russ=-

[idosubaru]

pulling the cats may help, i don't know, didn't help 2 XT6's i played with but that's not a huge sample size and i never dyno'ed them. they seemed to run better with a muffler than a straight exhaust pipe as well...but maybe that's me, again i've never dyno'ed anything. my best results were with slightly larger pipe from the cat back and a straight through style dynomax muffler. all i have are gas mileage numbers to go on and they were best with that combo as well. and of course this is all with an XT6, 6 cylinder so it's not even the same vehicle or motor. i would imagine dynomax might be a good one to ask if you're buying the cams from them anyway. did they offer any info?

[MilesFox]

take off the exhaust after the y pipe and have a flange welded to a 2 inch cherry bomb and run a straight pipe to the back with no muffler. use 1-3/4" pipe afterh the 'bomb

[Syonyk]

take off the exhaust after the y pipe and have a flange welded to a 2 inch cherry bomb and run a straight pipe to the back with no muffler. use 1-3/4" pipe afterh the 'bomb

 

How loud is that? I'm not opposed to a bit of noise, but I do have women riding in this car on a semi-regular basis. :-)

 

-=Russ=-

[idosubaru]

you can play with the muffler, that will influence what it sounds like the most. my favorite sound is a nice, straight through, free flowing dynomax muffler. they are excellent and sound great, but not loud. a few of us at xt6.net are using them on XT6's with good results. one person didn't like the sound level increase and wants to go back to stock. they aren't as cheap as cherry bombs though. maybe someone in your area has one already set up similar so you can check it out?