Hay guys

Ive done a heap of searching and reading on this forum. I'm looking at going down the 3.8l conversion track when I get some money together. Just wanted to ask
Wats a good exhaust size for the 3.8l would it benefit from a bigger exhaust bigger than 2.5" cause I was looking at rpw website and was reading there he said the 380 got good gains with a 3" catback?

Thankyou

Wouldn't bother with over 2.5 inch unless you are going to cam the engine and want the top end to go a bit harder

http://www.rpw.com.au/shop/index.php?option=com_content&task=view&id=202

This is we're I got some info from about the 3" exhaust system on the 3.8l engines.

Yea won't really matter, you won't see any real gains from 3 inch over a good 2.5

I wouldn't take everything that RPW says as gospel.

Plus, you need to keep in mind that the 380 exhaust system is more restrictive than the Magnas. I see there's no mention of the performance gains that a 2.5" exhaust system (with free-flowing mufflers etc) would give. I would wager that, everyone else being similar, there would be bugger-all performance gain on a 380 going from a 2.5" exhaust to a 3" exhaust.

Whatever Dave from RPW says/writes is only ever designed to extract the maximum amount of dollars from your wallet,the guy is a crook.

How about this setup, its running a 12psi supercharger though

http://imageshack.us/a/img827/4372/dsc03703n.th.jpg (http://imageshack.us/photo/my-images/827/dsc03703n.jpg/)

Where did you get your conversion done?

This setup is from a 380 GT in victoria, he has his own website
http://www.380db.com/forum/category-view.asp
Where did you get your conversion done?

It's our old mate Blackstar's car, banned some time ago from these forums.
He's had nearly as many different exhaust set ups as I have!

Yep thats him, lots of good info there

It's our old mate Blackstar's car, banned some time ago from these forums.
He's had nearly as many different exhaust set ups as I have!

when my 3.8 conversion conversion was done it was running through the standard Magna cat then a 2.5" single system which then spilt into twin rear mufflers.

It made 159.7 Kw at the wheels. I guess this indicates a similar gain to the RPW claim that power can increase of 10Kw or maybe more.
But i think it is more to do with the 3 cats that the 380's run.

If stock 6G75 I'd go the 2.5" but if you do further mods a 3" may be better???
Having said that i still have a 2.5" system (but with a high flow cat, and still have the twin rear mufflers) after fitting custom cams. Now makes 179kw.

when my 3.8 conversion conversion was done it was running through the standard Magna cat then a 2.5" single system which then spilt into twin rear mufflers.

It made 159.7 Kw at the wheels. I guess this indicates a similar gain to the RPW claim that power can increase of 10Kw or maybe more.
But i think it is more to do with the 3 cats that the 380's run.

If stock 6G75 I'd go the 2.5" but if you do further mods a 3" may be better???
Having said that i still have a 2.5" system (but with a high flow cat, and still have the twin rear mufflers) after fitting custom cams. Now makes 179kw.

Hay mate

Yeh I'd think with more modding cam etc an 2.75" or 3" would be good for a possible gain. U see lots of cars with cams have upgraded to bigger exhaust with great outcome. Nissan cars seem to love big exhausts my mates SR20 only a little 2.0l 4cl had really nice gains going to an 2.5" exhaust.

Cheers