I'm just curious really. I know some people on here think bigger is better for their pipework but was wondering if its actually benefitial having 4 inch exhaust pipes. Got a friend who has this and it sounds awesome

The benefit in pipe size comes from downpipes and back.

 

i.e. no performance increase if you just change the back boxes.

 

If you change all the exhaust for 4" from downpipes back then you will have much better airflow.

 

However due to our dual exhausts 4" is a bit overkill and 3" will surfice for very high bhp z's.

got single 4" set up on my swb...sounds like a 6 litre AC Cobra...the wife hates it :D

You can actually slow the flow of exhaust gasses down by going for too big a bore pipe work. This will then result in loss of bhp. For a TT the optimum bore size is 3", anything larger and you risk slowing the gasses down. You can fit what ever size exhaust tips on an exhaust system - this has no bearing on the flow rate of exhaust gasses as it is usually slowed down by the back boxes anyway. If you have a straight through system without back boxes & cats then the exhaust tips should be the same bore size as the rest of the pipe work.

 

Just my 2P worth.

until your running silly power then 3 inch as its been said is more than enough

 

Mike

Thanks guy. It wasn't the back boxes I was meaning. Mike what would u say was silly power to warrant going over 3 inch

Even on the 6.3 V8 i'll only be running 3 inch pipes, 2.5 inches to start off with.

 

As the guys say it's a twin system so not really worth having it any bigger than 3.

Hey guys

 

The people at longlife told me that 2 and 3/4 was as big as you would want to go on the zorst and 3 inch on the down pipes. for the same reasons.

 

You can actually slow the flow of exhaust gasses down by going for too big a bore pipe work. This will then result in loss of bhp. For a TT the optimum bore size is 3", anything larger and you risk slowing the gasses down. You can fit what ever size exhaust tips on an exhaust system - this has no bearing on the flow rate of exhaust gasses as it is usually slowed down by the back boxes anyway. If you have a straight through system without back boxes & cats then the exhaust tips should be the same bore size as the rest of the pipe work.

 

Just my 2P worth.

Thanks guy. It wasn't the back boxes I was meaning. Mike what would u say was silly power to warrant going over 3 inch

 

on a twin system then your talking 1000+bhp type!! on a single system which is what i was going to have made then a 3" will still support 600+ i would have thought so i was going to have a single 4" system made but your talking very very loud