Pictures of custom exhaust

[Mr. Horsepower]

Hehe, probably like crap :P What type of rear silencer do you run?

[der affe]

i have a stromg cat back and a 2 !/4" dual in/out mid pipe with a magnaflow muffler as a resonator/silencer.
i am still running dual pipes though.

[Mr. Horsepower]

For E36 or E30?

[der affe]

E30,
2.7 stroker, 292* cam, shorty headers, MAF, Dbilas ITBs,

[kid325e]

I wish I could hear a quality sound clip! Sounds like its' going to be good.

[nando]

Do you got a sound clip?

I have been looking at this setup for a while, looks like custom silencers though.

it looks pretty good, except that Y-pipe is a horrible design and it's also way too far back.

[FredK]

Jordan of exhaust design found.

[FredK]

jk

[nando]

hehe, no I didn't call him a stupid moron ;)

it's just that there is a LOT of ignorance when it comes to exhaust here. tryin' to help a brutha out, yo.

[nando]

I don't run cats, that is not needed and steals 5hp as well. As my car is a non cat car stock, I don't have to use cat on the S50.
Well, it will be a second muffler. I just mix the two of them.

I have a small love for the sound that is in the SS Race exhaust, but that is very loud and I may not be able to use the car on some tracks. With the S50B32 euro engine off course ;)

http://www.youtube.com/watch?v=2Tg8-OULjFk

understandable that you don't need one, but a 3" cat is probably not going to cause a significant restriction, and if placed after a well designed merge it can benefit the function of the headers as well as make it sound better and polute less. At least put a good resonator where the cat should be.

[Mr. Horsepower]

Nando - I have also noticed the bad design on that Y-pipe, but is there any "rule" on how far back it is placed?
I have seen examples where they run double pipes all the way to the rear where they collect in the same rear silencer. Without X-pipe.
And regarding the cat, it will not happen ;) lol

[nando]

there isn't really a hard rule, but it will affect where in the powerband the "5th" cycle happens (negative wave reflection, which is a secondary scavenging effect to velocity in the header).

Generally it's best to keep it within a couple inches of the stock x-pipe location, which is closer to the control arm bracket. this is mostly because the factory already did some of the guess work as to where the best location is, but you could of course tune this to your own engine and mods (cam, etc).

you can try finding some exhaust simulators on the web to get in the ballpark, but I have no idea how accurate they are. I went with 16" from the collectors for mine but I think the shop put it a bit further than that. I believe further away puts the effect higher up in the RPM range, but the one in that picture is probably so far away (and a poorly made) that it won't have any effect at all.

anyone who runs dual pipes with no X-pipe or a crummy Y-pipe that far away is missing out on an important peice of the exhaust, but so many people here want to run a small exhaust with only one muffler it's not surprising.

[newman]

[Burnera]

at what point is the diameter too big for these M20 engines?
I wanted to go with 2.25"ID or 2.5"ID

[nando]

at what point is the diameter too big for these M20 engines?
I wanted to go with 2.25"ID or 2.5"ID

2.5" minimum. 2.25" is smaller than stock. I would go 3" on any E30 but I'm probably crazy. ;)