Turbo exhaust size

[nmo93]

i would think about going w/ 3" diameter piping. that's what most turbo cars use. 2.5" might be a little on the small side. how loud do you think your car is going to be w/ the wastegate venting to the atmosphere? i know a ton of rx7 guys who do this at first, but then re-route it back into the dp or mp.nick

[ziggy682]

Well, 2.5" would be big enough if it was mandrel bent. Stay away from crush bent exhaust systems. If you are going with a custom setup, buy some 2.5" mandrel u-bends from JC Whitney, and have a shop cut and weld a system out of them. That would be the best cheap way to do it.

[syka24et]

yeah I agree 2.5 inch should be ok at ten lbs. I wonder if jc witney sells titanium pipes,

[kevdog240]

i dont understand why everyone is always saying 2.5 is fine? i guess i am wrong but i always thought that 2.5 was more for NA and 3 would be better for the turbo to let it get the exhaust out quicker.......

[noopz]

i think there are some Sr20's with 2.5inch turbo outlets out there that run on 10-12psi. not sure tho, could b wrong

[syka24et]

2.5in is ok because you can still maintain good velocity, while you want less back pressure, it is still important to make sure u have good velocity (corkey Bell). 2.5 for only 10lbs IMO is good a compromise with both. Are you sure you are only going to run 10lbs boost is addictive I started at 10 on my integra thinkin the same thing then it was 12 then 15, before I new it I had to get a bigger exhaust, intercooler piping it was waste.

[nick]

how much power did you gain by having your wastegate vent to the atmosphere

[Wolf240SX]

if your looking for a price on exhaust system I just had a full exhaust system made 3" for $400 "no muffler" That was a full exhaust from down pipe out the rear bumper.

[WDRacing]

I wouldn't go with anything smaller then 3". Unless you already have a 2.5 installed. Then I would make do.

If you have the wastegate pipe plumbed back in, its a good idea to go 12 to 14 inches down the dump pipe. This will keep the exhaust flowing in the correct direction.

WD

[nick]

where can you buy mandrel bends from?

[kevdog240]

i bought a 5zigen fireball exhaust but the 2.5 because my car is still NA and at the time i didnt think i was going to put a turbo on. now that i am turboing should i buy 3" downpipe for it and keep the exhaust til i can afford to swap it? will that mess it up though?

[WDRacing]

Should be fine...the power increase won't be that noticeable.

[C-Kwik]

I noticed a nice increase in response and power when I switched from my 60mm Greddy to my 80mm Greddy. Though it came with a price of more noise. Turbos use a little different approach to exhaust size. While it is good to keep decent velocity, turbines are sensitive to the pressure differential across the turbine wheel. With less backpressure, given the same exhaust manifold pressure, it will spool the turbo faster and run more efficiently, since more air can be diverted through the wastegate for the same boost level. Since air going through the wastegate flows freer(the turbine is a restriction no matter how you look at it), you free up some additonal HP. Generally the rule of thumb for a turbo exhaust is to go as big as your ears can bear.

[Wolf240SX]

Hey 98KA24DET Here is a pic of my Nsport Kit installed.

[kevdog240]

wolf240sx do you have any close up pics from different angles of your engine? i am going to start piecing my stuff together and want to model it after the nsport kit. i still have a bunch of reading to do on turbos but i mean like where the lines are coming from and that stuff.......

thanks

[gyfer]

80shot on stock fuel system ??God bless you....