** Polished Combustion Chambers **
** Polished Combustion Chambers ** Should you do it?
I am going to be buying a set of "Stage 1" heads (with stock size Manley valves) from a friend and he has informed me that they are not polished.
What are the advantages and disadvantages of doing this.
BTW - The heads are from a 98 LS1 and have been milled .050
Thanks in advance...
Bill
I am going to be buying a set of "Stage 1" heads (with stock size Manley valves) from a friend and he has informed me that they are not polished.
What are the advantages and disadvantages of doing this.
BTW - The heads are from a 98 LS1 and have been milled .050
Thanks in advance...
Bill
Re: ** Polished Combustion Chambers ** Here's my take FWIW, I'm not an expert by any means:
Polishing the chamber doesn't really gain you any power. It might help a little with avoiding carbon build up in the cylinder head.
The down side of polishing the chambers is if the person doing the polishing doesn't really know the right way to polish the chamber, you'll end up with a tiny divit near the valves. This will kill flow on most heads. If a divit occures the power maybe way down.
So I'd skip the polishing.
Now if the orginal head porter is game for doing the polishing for you, get them to do it, if you really want this.
BTW I have no idea what this should cost, but I figure if I have carbon build up that's what the decarbon treatments are for.
I've been told a properly CNC'd head won't really retain much carbon. With hand porting I guess it will vary with the quality of the job done.
Polishing the chamber doesn't really gain you any power. It might help a little with avoiding carbon build up in the cylinder head.
The down side of polishing the chambers is if the person doing the polishing doesn't really know the right way to polish the chamber, you'll end up with a tiny divit near the valves. This will kill flow on most heads. If a divit occures the power maybe way down.
So I'd skip the polishing.
Now if the orginal head porter is game for doing the polishing for you, get them to do it, if you really want this.
BTW I have no idea what this should cost, but I figure if I have carbon build up that's what the decarbon treatments are for.
I've been told a properly CNC'd head won't really retain much carbon. With hand porting I guess it will vary with the quality of the job done.
Re: ** Polished Combustion Chambers ** Nate,
Made a good point. Might be worth checking out a set of fresh stage 1 99-02 heads from someone like TEA, so you don't have to fool with changing the coil packet brackets and rails etc.
www.totalengineairflow.com
They also do group purchases and have excellent prices. The dual springs are a big plus too.
<small>[ October 26, 2002, 06:55 PM: Message edited by: 99 Black Bird T/A ]</small>
Made a good point. Might be worth checking out a set of fresh stage 1 99-02 heads from someone like TEA, so you don't have to fool with changing the coil packet brackets and rails etc.
www.totalengineairflow.com
They also do group purchases and have excellent prices. The dual springs are a big plus too.
<small>[ October 26, 2002, 06:55 PM: Message edited by: 99 Black Bird T/A ]</small>
TECH Enthusiast
Joined: Sep 2002
Posts: 658
Likes: 0
From: Clinton Twp. Michigan
Re: ** Polished Combustion Chambers ** If you are going with older style heads, all you will need to do is buy older Valve covers, the coil packs mount directly on the valve covers on 97/98 LS1's, but GM had/has issues with the fact that with the coil packs sitting directly on the valve covers, they get too hot, and it decreases there life span. I have to buy new packs now on my 98 Z since they are taking a ****, and doing weird things.
just fyi
Jason
just fyi
Jason
TECH Senior Member
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
Re: ** Polished Combustion Chambers ** Why polish? It wont be polished for long <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> <img border="0" alt="[Fluffy]" title="" src="graemlins/fluffy.gif" />
