Exhaust Requirement For 800+hp

[SLY33]

Exhaust threads seem to be in fashion at the moment so ill throw in this query.

What do people usually run on a street car making 800+HP? (btw not implying i expect it to make legal volume!)

I was thinking i'd benefit from a 4inch system, yet I have looked at all the Jap systems on most of the popular websites, and havent found anything larger than 3.5inch.

The question would then be, will an unrestrictive 3.5inch system hold back power potential?

The setup in question is a single turbo RB28.

Looking at the recent custom exhaust thread, custom could be the way to go, but for simplicity id rather a system i can just bolt in. I have heard of a 4inch HKS system, but cant find any details. Im aware that its gonna be noisy.

thanks for any help

[2BNVS]

a street car making 800+HP?

not usually something u see all that often, but i run a 4" dump 3.5" cat back with 600rwhp so i would go 4" all the way for 800

ben...

[400kw]

Exhaust threads seem to be in fashion at the moment so ill throw in this query.

What do people usually run on a street car making 800+HP? (btw not implying i expect it to make legal volume!)

I was thinking i'd benefit from a 4inch system, yet I have looked at all the Jap systems on most of the popular websites, and havent found anything larger than 3.5inch.

The question would then be, will an unrestrictive 3.5inch system hold back power potential?

The setup in question is a single turbo RB28.

Looking at the recent custom exhaust thread, custom could be the way to go, but for simplicity id rather a system i can just bolt in. I have heard of a 4inch HKS system, but cant find any details. Im aware that its gonna be noisy.

thanks for any help

HEY mate note what turbo set up you are running ,but im running twin turbo on 30/25 .and was running single 4 ich ,and then went for a custom twin 3 inch off dumps right through and it made a tiny bit more power ,but im only running 720 rwhp at the moment ..

[R31Nismoid]

3.5" wouldnt even enter the equation... gotta be minimum of 4" id imagine... and thats with externally venting gate.

Or as above, 3" twin.

[SLY33]

Just to clarify, 800 flywheel HP. so looking at the over-600hp at the wheels range.

turbo is rated at 850HP.

400kw, a twin 3inch system sounds like a lot of flow! How loud is your setup, any muffled sections or is it a race setup?

[N1GTR]

Screamer?

[SLY33]

Screamer?

i wasnt planning on one. ive only heard one whilst running against another car. hearing it from inside my car it sounded dodgy, cant really say tho as ive only heard the one.

[400kw]

Just to clarify, 800 flywheel HP. so looking at the over-600hp at the wheels range.

turbo is rated at 850HP.

400kw, a twin 3inch system sounds like a lot of flow! How loud is your setup, any muffled sections or is it a race setup?

with the 4 inch system ,it was loud and its dronned really bad ,but that was with no muffles just a rear cannon,with the twin 3 inch i have 6 hotdogs in it ,3 each side and 2 cannon out the back its not as loud ,as the 4 inch ,buts still loud ,but it doesnt dronn no where near as the 4 inch ...i would look around at 3.5 inch system .

[r33_racer]

we supported somewhere between 470-500rwkws with a 4" system from turbo back, no mufflers though with w.g merging straight into the dump pipe. Race car so it was loud....

[R31Nismoid]

pulp or race fuel?

That does make some difference to it all at times.

[rb26s13]

a well built custom 3.5" or 4" would do the trick i'd imagine.. after seeing seans exhaust im quite tempted to use those magnaflow mufflers as they look to be of good quality

just make sure you use a good quality cat.. im a big fan of the catco and metalcat cat's with 5" round body they flow really well.

[SLY33]

pulp or race fuel?

majority of the time it will be pulp

[Spoolup]

Youll be pressed to make 800 bhp on pump.

Im making 720 bhp with a full 3.5 inch exhaust and dump, screamer is plumbed back into the exhaust, runs a cat and is legal noise.

[SLY33]

Hi Brad

Hopefully i will find out very soon. My engine dyno session is long overdue, should be close!

cheers

[Swiper the Fox]

Hi Brad

Hopefully i will find out very soon. My engine dyno session is long overdue, should be close!

cheers

4 inch...800hp...no problem

[SLY33]

thanks for the recommendations, it seems 4inch is the go.

the last remaining question is are there any nice off the shelf 4 inch systems? As mentioned i have heard of an HKS 4inch system, but i cant find it, or any other 4inchers available, only 3.5's.

cheers!

[bigmikespec]

thanks for the recommendations, it seems 4inch is the go.

the last remaining question is are there any nice off the shelf 4 inch systems? As mentioned i have heard of an HKS 4inch system, but i cant find it, or any other 4inchers available, only 3.5's.

cheers!

Trust/Greddy have a Power Evolution II exhaust which is 94mm so close enough to 4". I am pretty sure Twoogle had one (ask Paul). I have one on my R33 GTR. Comes with a cat replacement pipe, check with Croydan Racing Dev. that is where I got mine from, they were clearance stock.

Mike

[jet_r31]

little man, i run a 3.5 inch dump with a 3 inch system with i muffler and a resonator muffler, its quiet.

Gate is vented externally. So far on pump fuel through a powerglide its made 630rwhp

and so far isn't a prob.

cheers

darren

[SLY33]

little man, i run a 3.5 inch dump with a 3 inch system with i muffler and a resonator muffler, its quiet.

Gate is vented externally. So far on pump fuel through a powerglide its made 630rwhp

and so far isn't a prob.

cheers

darren

LOL no shit, is this bluebird/VLT Darren??! I havent been called that in years! HAHA

[Lithium]

400kw, a twin 3inch system sounds like a lot of flow! How loud is your setup, any muffled sections or is it a race setup?

Just for interests sake, a twin 3" exhaust would have the same cross sectional area as a single 4 1/4" exhaust so its not actually as wild as it sounds. Depending of course on how wild you think 4 1/4" is