PORT AND POLISHED EXHAUST MANIFOLDS

[pgriffith]

would it help to port and polish the stock exhaust manifolds. It would be way cheaper then a pair of headers. Would it be very effective?

[Dominic]

No - not really.

[pgriffith]

Ok your probly right....

But why exactly?

[Seppo Kaitainen]

Its not cheap, and you will gain very little.

[Dojo2000]

<blockquote>quote:</font><hr>Originally posted by Dominic:
No - not really.<hr></blockquote>

<blockquote>quote:</font><hr>Originally posted by pgriffith:
Ok your probly right....

But why exactly?<hr></blockquote>
Yeah, isnt' it nice when they say just yes or no. Its very informative :rolleyes:

<blockquote>quote:</font><hr>Originally post by Seppo Kaitainen
in this post
I found out some about having them ported. There are like only two ways to do it.
1 is to cut them in half, port them and weld them back together.

2 is the flow some fluid with metal in it though the manifolds.
<hr></blockquote>

but he is talking about the '00+ manifolds, not sure if that applies to the pre-'00 manifolds though.

[img]graemlins/burnout.gif[/img]

[ June 10, 2002: Message edited by: Dojo2000 ]</p>

[pgriffith]

Ok thanks for the educated guesses. I could have done better not asking. I think I will do it anyways, I am replacing heads and cam, and I know a guy with a shop that has all the tools. So its FREE. Couldnt hurt trying specially when it cost $free.99.

[Silver3800V6FBodyKY]

I agree:

A one sentence reply does no good at all. The reason people ask questions on here is to learn more about our cars. Not simply what can, and can't be done. People like to know why things will, and won't work.

And personally, polishing and porting the exhaust manifolds will be effective - how effective is the question. Any way air can move with less restriction will result in power gains. You might only gain 3-5 Horsepower, but if it's getting done for free, I would do it.

Jon

[Dominic]

Its not the roughness of the exhaust manifolds that causes you to lose horsepower, its the shape and form of them. Polish them all you want, you won't see anything from it.

Headers are more smoothly bent, and are usually tuned to be equal length - your manifolds are nothing like that, tubular or square!

[pgriffith]

Thanks Dominic, thats alot more descriptive, makes sense.

[viper98885]

Is there any problem with running the '00 + exhaust manifolds on a '95-'99 3.8L V6. This is a research question by the way. The heads on the '95-'02 have the same part number so both style of exhaust manifolds will bolt up to the heads, but what about the y-pipe or clearance issues with other parts.

[Dominic]

<blockquote>quote:</font><hr>Originally posted by viper98885:
Is there any problem with running the '00 + exhaust manifolds on a '95-'99 3.8L V6. This is a research question by the way. The heads on the '95-'02 have the same part number so both style of exhaust manifolds will bolt up to the heads, but what about the y-pipe or clearance issues with other parts.<hr></blockquote>

The tubulars are 100% interchangeable with the older square style. They are the same length and will bolt correctly to any existing Y-pipe. One of my old buddies has 00 Manifolds on his 99, he didn't see a performance gain really (we couldn't feel a difference), but changing his plugs were a lot easier [img]smile.gif[/img] .