Modifying stock LS1 heads?
Thread Starter
Former Vendor
Joined: Nov 2005
Posts: 8,995
Likes: 2
From: Spring Texas
St. Jude Donor '08
Modifying stock LS1 heads?
Given that aftermarket heads are among the more expensive performance modifications to do to your car, I'm wondering if any of you have modified your stock heads (ported/polished milled etc) for better flow. How does this compare to aftermarket heads in performance and price?
thanks.
thanks.
Team Owner
Joined: Mar 2005
Posts: 32,262
Likes: 35
From: Somewhere between mild insanity and complete psychosis
Given that aftermarket heads are among the more expensive performance modifications to do to your car, I'm wondering if any of you have modified your stock heads (ported/polished milled etc) for better flow. How does this compare to aftermarket heads in performance and price?
thanks.
thanks.
You can get stock ls1 heads worked for anywhere from $400-$600 if you look around, and gain anywhere from 20-30 rwhp depending on cam, bolt-ons, etc. They certainly won't get you 50-80 rwhp like the big time heads, but it doesn't cost $1300-$2,300 either.
Basically it is a step down, but the price you pay and performance you get are in line with each-other. Certainly worthwhile if on a budget and you absolutely can't afford new heads but can afford a good port job.
Safety Car
Joined: Sep 2004
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I think a lot of it has to do with who is doing the port work as well. I picked up 39RWHP and 70RWTQ with heads, ported thottle body, descreened MAF and tune. I paid about 700 for port work. Check my thread on my install and results:
http://forums.corvetteforum.com/show....php?t=1846963
http://forums.corvetteforum.com/show....php?t=1846963
Last edited by MJD; Dec 1, 2007 at 02:02 AM.
Thread Starter
Former Vendor
Joined: Nov 2005
Posts: 8,995
Likes: 2
From: Spring Texas
St. Jude Donor '08
I currently have:
vararam intake
Ported TB
WCC X pipe
Borla stingers
I'm thinking I should probably invest in a set of headers first, then worry about the heads.
vararam intake
Ported TB
WCC X pipe
Borla stingers
I'm thinking I should probably invest in a set of headers first, then worry about the heads.
Safety Car
Joined: Sep 2004
Posts: 4,762
Likes: 0
Racer
Joined: Sep 2002
Posts: 424
Likes: 0
From: Va, Beach VA
I think a lot of it has to do with who is doing the port work as well. I picked up 39RWHP and 70RWTQ with heads, ported thottle body, descreened MAF and tune. I paid about 700 for port work. Check my thread on my install and results:
http://forums.corvetteforum.com/show....php?t=1846963
http://forums.corvetteforum.com/show....php?t=1846963
I picked up the same when I had mine ported. Suggestion.... find the best person to port your heads and you won't be sorry. From my point of view for what the aftermarket wants for heads you can port yours and buy headers for about the same price or less. It really depends on your performance goals in the long run. Want to make 450hp + go aftermarket. 450 or less a stock ported head will get you there , both with the necessary add ons.
Race Director
Joined: Dec 2003
Posts: 12,599
Likes: 1
From: Texas
I was completely unaware that ported stock heads could net such good numbers. Were any of you guys already tuned and gained from the heads and a retune? Just wondering if any of these numbers were over the stock tune or custom tune.
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Safety Car
Joined: Sep 2004
Posts: 4,762
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I was running on a custom street tune when I had just cam/longtubes. The car ran well but in my opinion the tune still needed a little work. I could still get more out of the car now but elected to keep the tune on the safe side. My AFR is right around 12.4.
Racer
Joined: Jun 2007
Posts: 392
Likes: 1
From: TX
As previously stated for a nice cleanup, port, polish, mill you are looking at about $600-700 dollars just for the labor and that is staying with your stock valve springs, valves, etc.
When you take into account that you might upgrade your cam and will require better valve springs or possibly want to go with bigger valves then the price will go up and possibly beyond what a brand new set of ported & polished GM casting heads(not aftermarket AFR or TFS castings) would have cost you fully built with bigger valves, double springs, titanium retainers from some place like Patriot Performance, Texas-Speed, or Livernois.... I mean the Comp 918 springs are around $190 a set and the 921 doubles are $400 so you are already up to around $900-$1100 and you still have stock valves, retainers, locks, etc. So a nice set of Patriot Performance Stage II 243 casting heads with larger 2.02/1.57 valves, doubles springs, titanium retainers, etc. for around $1100 is not such a bad price after all - then you can turn around and sell your stock heads for $200 if they're LS1 heads and be back down around $900-$1000 - Just some food for thought...
Hope this helps you out! But you need to get some headers sooner or later... 
When you take into account that you might upgrade your cam and will require better valve springs or possibly want to go with bigger valves then the price will go up and possibly beyond what a brand new set of ported & polished GM casting heads(not aftermarket AFR or TFS castings) would have cost you fully built with bigger valves, double springs, titanium retainers from some place like Patriot Performance, Texas-Speed, or Livernois.... I mean the Comp 918 springs are around $190 a set and the 921 doubles are $400 so you are already up to around $900-$1100 and you still have stock valves, retainers, locks, etc. So a nice set of Patriot Performance Stage II 243 casting heads with larger 2.02/1.57 valves, doubles springs, titanium retainers, etc. for around $1100 is not such a bad price after all - then you can turn around and sell your stock heads for $200 if they're LS1 heads and be back down around $900-$1000 - Just some food for thought...
Hope this helps you out! But you need to get some headers sooner or later...
Racer
Joined: Jun 2007
Posts: 392
Likes: 1
From: TX
Team Owner
Joined: Sep 2003
Posts: 43,084
Likes: 33
From: Raleigh / Rolesville NC
As previously stated for a nice cleanup, port, polish, mill you are looking at about $600-700 dollars just for the labor and that is staying with your stock valve springs, valves, etc.
When you take into account that you might upgrade your cam and will require better valve springs or possibly want to go with bigger valves then the price will go up and possibly beyond what a brand new set of ported & polished GM casting heads(not aftermarket AFR or TFS castings) would have cost you fully built with bigger valves, double springs, titanium retainers from some place like Patriot Performance, Texas-Speed, or Livernois.... I mean the Comp 918 springs are around $190 a set and the 921 doubles are $400 so you are already up to around $900-$1100 and you still have stock valves, retainers, locks, etc. So a nice set of Patriot Performance Stage II 243 casting heads with larger 2.02/1.57 valves, doubles springs, titanium retainers, etc. for around $1100 is not such a bad price after all - then you can turn around and sell your stock heads for $200 if they're LS1 heads and be back down around $900-$1000 - Just some food for thought... Hope this helps you out! But you need to get some headers sooner or later...
When you take into account that you might upgrade your cam and will require better valve springs or possibly want to go with bigger valves then the price will go up and possibly beyond what a brand new set of ported & polished GM casting heads(not aftermarket AFR or TFS castings) would have cost you fully built with bigger valves, double springs, titanium retainers from some place like Patriot Performance, Texas-Speed, or Livernois.... I mean the Comp 918 springs are around $190 a set and the 921 doubles are $400 so you are already up to around $900-$1100 and you still have stock valves, retainers, locks, etc. So a nice set of Patriot Performance Stage II 243 casting heads with larger 2.02/1.57 valves, doubles springs, titanium retainers, etc. for around $1100 is not such a bad price after all - then you can turn around and sell your stock heads for $200 if they're LS1 heads and be back down around $900-$1000 - Just some food for thought...
Hope this helps you out! But you need to get some headers sooner or later... I had my LS1 ( 241) heads P&P. Pickup a whole 7hp. Maybe the guys was not that good. and or the other mods I had made up the difference.
Then I bought a set of slightly used 243 ( LS6 heads ) for $800. There was some Porting work done on the heads. I put some much better springs, Comp 981 , and a Comp cam 224/228 581/581 112 lsa - that woke the car up
So I also agree it is not really worth the time to port and polish 241 heads.
But Good Luck on your project.
Remember when you do it on the cheap, you will do it 3 or 4 times to get it right. Save and spend a few more dollars up front to get right the first time.
Safety Car
Joined: Sep 2004
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If ls1 heads weren't worth the time to port you would not have companies like TEA offering them on exchange. LS1 heads can be ported to flow on par with a ported ls6 head. The idea that they're not worth it is marketing hype in my opinion. Vendors can't make as much money if you're not willing to dish out the dough for a replacement head instead of doing an exchange.
