Page 1 of 1
2.8 exhaust
Posted: Sat Jun 30, 2007 7:53 pm
by taity
hey guys just after some info for an exhaust for a 2.8turbo GQ.i have a set of 33" tyres and find it lacks of power down low. i thought of upgrading the exhaust and just want to know if anyone can help me on what size is good and to run it straight from the turbo or... also if i was to upgrade the dump pipe would the size of it be the same as the exhaust? any help would be great. thanks
Posted: Sat Jun 30, 2007 8:01 pm
by familybus
3" all the way
Posted: Sat Jun 30, 2007 8:10 pm
by taity
some people say its too big for the 2.8 others say 3" all the way. any help on this please guys
Posted: Sat Jun 30, 2007 8:55 pm
by HotFourOk
Basically, with a turbo you can't go 'too big'. The free-er the better I always think, although with a naturally aspirated motor, too large of an exhaust will have detrimental effects.
On my Rocky 2.8TD I used 2.5" from turbo outlet back and its perfect I believe.
Posted: Sun Jul 01, 2007 2:55 pm
by zagan
Same boat myself, not really sure what size is good I was thinking 3.5inch but you can do 3"-4" from turbo and go 3.5"-4" half way through.
Going big is good but if you ran with very little back prusre the valves can start pulseing back presure stops this pulsing.
Posted: Sun Jul 01, 2007 7:16 pm
by crack
i have a turboed 2.8 hilux on 33's and they the bloke hughly reccomended 21/4" exhust so that what i went. nt sure how different the motors are betwen the two are tho
Posted: Sun Jul 01, 2007 11:11 pm
by HotFourOk
zagan wrote:Same boat myself, not really sure what size is good I was thinking 3.5inch but you can do 3"-4" from turbo and go 3.5"-4" half way through.
Going big is good but if you ran with very little back prusre the valves can start pulseing back presure stops this pulsing.
Only with a naturally aspirated car though, his is turboed.
Posted: Mon Jul 02, 2007 12:57 am
by zagan
crack wrote:i have a turboed 2.8 hilux on 33's and they the bloke hughly reccomended 21/4" exhust so that what i went. nt sure how different the motors are betwen the two are tho
How big is it stock?
My turbo diesel is 2 1/2" stock.
I assume this to be a diesel?
Posted: Mon Jul 02, 2007 11:50 am
by crack
yeh mate its a diesel i had the turbo put on last week. when i got the car it had what i beleive was the stock exhust which one 1inch somthing then i went 2" and extractors now turbo and 21/4" pipe
Posted: Mon Jul 02, 2007 4:38 pm
by KiwiBacon
If you want to cut through all the BS regarding exhaust size.
Plumb a boost gauge into your exhaust just after the turbo.
Measure the actual restriction you're getting and see if it's worth upgrading. The muffler has a much bigger effect on backpressure than the size of the pipe.
A ballbearing turbo will give your more low-end. More fuel will also give you more low end (at the risk of black smoke).