3 inch Exhaust?

[Matt Cole]

Has anyone produced a 3" full exhaust system for the GTT? I'm looking at the possible future benefits (if any) with my setup and possibly ditching the side exit in favour of a decent full system. :agree:

[Ian S]

CTM / bigjimracing.co.uk did a turbo to rear exit 3 inch system for one of their 5GTT's. Was a years ago though.

I have an idea that Mike Spencer had Simpsons exhausts make a 3 inch one for that ill fated green/purple EFI 5GTT.

[BluntyR5GTT]

Longlife could make u one mate. Hearing alot of good things about them atm

[philr5t]

i had big jim make me a 3 inch down pipe straight from the turbo and i also have powerflow waiting for me to get the car down to them to make the rest of the 3 inch exhaust mine is a sidey though

[Sparkie]

it will rattle over the rear beam. the gap it has to fit through will be uber tight (left to right gap)....

best check before getting it made?

[philr5t]

it will rattle over the rear beam. the gap it has to fit through will be uber tight (left to right gap)....

best check before getting it made?

i take it you mean it will rattle for a rear exit exhaust mate

[markey b]

my bro had a 2.5" rear exit on his and it was 'snug' over the rear beam

[philg]

Bloody hell mat how much power do you want to push out of it :eek:

[Matt Cole]

Bloody hell mat how much power do you want to push out of it :eek:

Ha, i was thinking 'future proof' if i decide to remove the ill fitting side exit and replace with something meaty. It may be over kill i dont really know as i aint done any calcs to determine any benefit. I had heard that the Evo's and Impreza etc seem to upgrade to a 3" but not sure if its tuner BS or any real gains to be had.

A discussion on here would be nice!:D:agree:

[Mart]

Imho, 3" bore isn't required until at least 400hp (assuming turbo application), and even then, that would then depend more so on overall length of the system, how many bends (and what angle they are), etc.

[philg]

Imho, 3" bore isn't required until at least 400hp (assuming turbo application), and even then, that would then depend more so on overall length of the system, how many bends (and what angle they are), etc.

I agree with Mart Mat. Straight as possible is always best. I upgraded from a 2.5 to a 3" and noticed no difference whatsoever.

I think with evos and scoobs like mart said most are running 350hp+. I was also told a larger exhaust can give you larger hp but can negative affect on how the car make torque.

What size is on now mat?

[raj]

just a thought....
why not have the 3"exhaust system up to the middle of the car..at this point fit an exhaust cutout valve?
if you get the actuator type (http://www.motorwrench.com/blog/wp-content/uploads/2009/03/atp-acs-010_450.jpg) you can the have it flip open at the same time your turbo starts spooling. anything before boost and the valve will not open resulting all gasses exiting in the normal manner,rear or sidey.

[TNT ANDY]

Rule of thumb - 1inch per 100bhp ;)

[DK DEVELOPMENTS]

My exhaust is 3inch side exit was fabricated by simpson race exhausts.
will get pick of complete exhaust the weekend.

[rs250nut]

So for 700hp we need a seven inch exhaust:D

[Matt Cole]

I agree with Mart Mat. Straight as possible is always best. I upgraded from a 2.5 to a 3" and noticed no difference whatsoever.

I think with evos and scoobs like mart said most are running 350hp+. I was also told a larger exhaust can give you larger hp but can negative affect on how the car make torque.

What size is on now mat?


It's a 2.5" tiger side exit Phil. I guess plentifull for now, but is it any good for over 300bhp? TBH i might not even have enough room as its tight for the down pipe as it is.

[J$£5GTT]

So for 700hp we need a seven inch exhaust:D

:laugh:

[philg]

It's a 2.5" tiger side exit Phil. I guess plentifull for now, but is it any good for over 300bhp? TBH i might not even have enough room as its tight for the down pipe as it is.


Sound like what you have will be fine and alot less hassel, you just dont want it to be overkill, (like most of my car :)).

Whats ashy got on his, is his car not running over 300hp?


phil

[Matt Cole]

Sound like what you have will be fine and alot less hassel, you just dont want it to be overkill, (like most of my car :)).

Whats ashy got on his, is his car not running over 300hp?


phil

Nothing at the moment because it's in bits!!:D

He's rebuilding his lump for a possible 300bhp target. TBH plentifull in a 5! I think he was using a 2.5" side exit too.

[raj]

any ideas on what full 2.5" rear exit systems are on the market.? im starting to get annoyed with this side exit.

[Duncan Grier]

Imho, 3" bore isn't required until at least 400hp (assuming turbo application), and even then, that would then depend more so on overall length of the system, how many bends (and what angle they are), etc.

:agree:

Well on the vx220 turbo 2.5 is fine to upto about 300bhp, stick a decent 3" and goes up 10bhp ;) of the same spec engine / turbo

The exhaust is not long but 2 180deg bends - I would not think on a GTT engine there would be much to gain from 3inch over the 2.5

I have also seen some larger exhausts loose power in places

Would imagine its a bit tight to get a full rear 3inch on the 5 but def possible and can always do what they do for some of the vag downpipes in tight areas of splitting into 2 smaller pipes and back to the larger, of squeeze the bad boy :cooter:

DG

[Spooky]

My exhaust is 3inch side exit was fabricated by simpson race exhausts.
will get pick of complete exhaust the weekend.

Ive just ejaculated...

[tubby5]

Ive just ejaculated...

I would hate to think what the pics are gonna make you do:scared:;)

[Matt Cole]

Well I think I'll look into 3" and report back! Cheers