m20b28 exhaust

[Nobimmer 694]

I am going to get a new exhaust made this week before I go on the dyno next week. What is the best setup to use with the b28? I am pretty sure I will stick with a single 2 1/4 inch pipe off the headers and use one decent muffler to a pipe out the back/ front of the back wheel.

What have other people used with the stroker/ what would be the best setup to use here? My current 3 inch, shitty muffler, shitty collecter, shitty resonator is not working at all.

Cheers

Ashkan

[hybrid 1044]

I am going to get a new exhaust made this week before I go on the dyno next week. What is the best setup to use with the b28? I am pretty sure I will stick with a single 2 1/4 inch pipe off the headers and use one decent muffler to a pipe out the back/ front of the back wheel.

What have other people used with the stroker/ what would be the best setup to use here? My current 3 inch, shitty muffler, shitty collecter, shitty resonator is not working at all.

Cheers

Ashkan

This was explained to me when I did mine which is essentially the same design youre after being a mid 6 cylinder.

Best mid range torque power below

For NA in your literage

Engine: eqaul 3 into 1 then dual 2 inch thin walled stainless pipes all the way as far as possible to a rear muffler, the straighter the more power you make but you make more noise.

You can run an x-pipe if you wish however it requires tuning on the dyno to make real power, if you get it wrong = less power than you started with. For x-pipes you really need a dyno and fabricator with some test pipes to do it properly .. basically $$$

For higher RPM cars (+7k rpm cams + head upgrade (more flow) ) same formula accept use 2.5 inch piping.

[Surge 1]

The factory piping (combined dual) surely would be over 2 1/4" wouldn't it? My logic would be to run at least 2.5" for a 2.8 N/A... I don't know if there is any merit in that but I'd be keen to hear others opinions.

(Hybrid beat me too it!)

Edited October 17, 2011 by Surge

[Nobimmer 694]

This was explained to me when I did mine which is essentially the same design youre after being a mid 6 cylinder.

Best mid range torque power below

For NA in your literage

Engine: eqaul 3 into 1 then dual 2 inch thin walled stainless pipes all the way as far as possible to a rear muffler, the straighter the more power you make but you make more noise.

You can run an x-pipe if you wish however it requires tuning on the dyno to make real power, if you get it wrong = less power than you started with. For x-pipes you really need a dyno and fabricator with some test pipes to do it properly .. basically $$

For higher RPM cars (+7k rpm cams + head upgrade (more flow) ) same formula accept use 2.5 inch piping.

Will be doing some head decent head work eventually with a more aggresive cam and porting etc. So would I be safer to use the 2.5 version?

So basically, keep it as straight as possible for as long as possible? No resonator, decent muffler?

[Nobimmer 694]

Ok, so I did the exhaust today. Huge thanks to Mike at Pit stop Westgate, real GC to deal with.

Goes from the headers into twin 2 1/4 pipes to a freeflow 2 in 2 out muffler and dumps out the side of the car.

Just around the street I have found it does pull a little bit harder from about 2500 but can't really say too much without taking it to the track and seeing what happens.

The sound is not much different to before just a little louder. If I had more time/money I would have cut some of the floor out and had the pipes stick out through the sill and side skirts, although I have left the tips as a slip join so changing the configuration should be pretty simple to do later on.

Going on the dyno next week for a remap and tune so will see how we go.

[hybrid 1044]

Nice man! cant wait for the dyno.

silver tape / shield the paint?

[Nobimmer 694]

Yeah will sort something out, atm just ally tape but will make up an ally plate.

[westy 614]

Awesome.