$30 exhaust mod

[Zeke]

Cheap way to get extra power and fuel economy is to wrap our exhaust manifold/headers & downpipe with heat resistant exhaust wrap.

When exhaust gases are pushed out of your cylinders to your exhaust manifold, the air surrounding the manifold begin to cool the gases. This cooling process reduces the velocity of the escaping gases and the engine must 'work' to push the gases through your exhaust system.

Wrapping the exhaust headers with exhaust wrap maintains hotter exhaust gases that exit the system faster through decreased density. Increased exhaust scavenging is produced, along with lower underhood and intake temperatures. Also those with a cat or high-flow, it can operate more efficiently since hotter gases would elevate burning of pollutants.

Ako has mentioned before wrapping your entire intake with the wraps and I completely agree.

Here is that VR4 with the wraps:

[i3ooyah]

can you feel the difference though? i had a friend do the same thing to his intergra and lost power, which was proven on a dyno run.

[Kenneth]

Also what about the effect on life expectancy of your headers and exaust?

[dickytim]

free exhaust mod nets good power increase.......Take the tailpipe off

[Kieran]

Interesting Info Zeke - Thanks!

Hmmm...... I think I may have found something else to add to the list of things to do....

[paulmc]

I read somewhere not to insulate the manifold or down pipe as you lose power but i cant find it or remember the theory behind it

[ako]

I've always been told this is a bad idea with cast iron manifolds / exhausts - like ours, well, the downpipes at least. Theory is it gets things even hotter than they should be, and the iron cracks.

Bugger it, I'll probably do it anyway. One thing I've always been taught is that with a turbo'ed vehicle, trick is to just get the gas out as fast as possible. Hotter = faster = more power.

I'll try and do before + after dyno runs if I can though, or at least 1/4 mile runs. Trap speed tells you something at least.

[AllBeItMine]

not a good idea dude.

a turbo works on the principle of heat exchange. You have HOT High pressure gasses on one side and cool open space on the other. The bigger the difference, the more the turbo spins.

If you want to make an improvement on your car, wrap up your manifolds, not your dump pipes.