What gains to expect from LS6 head swap only?
10-05-2011, 12:39 PM
#41
You know, people have been getting nice results by doing heads first.
Im gonna try this with my next car as well. A nice aftermarket head, or some AI 243s with a FAST intake and boltons.
I know its not the norm, but Im gonna do it backwards, heads first then pick a cam.
Its worked out well for others.
https://ls1tech.com/forums/dynamomet...stock-cam.html
Im gonna try this with my next car as well. A nice aftermarket head, or some AI 243s with a FAST intake and boltons.
I know its not the norm, but Im gonna do it backwards, heads first then pick a cam.
Its worked out well for others.
https://ls1tech.com/forums/dynamomet...stock-cam.html
10-05-2011, 08:24 PM
#42
Although it may not be the most budget friendly approach, you should always do heads before a cam. Just talk to any cam designer, and they will tell you if you have stock heads, they'll design a cam in a certain way. If you have worked heads, they'll design a different cam. Every cam questionaire card always asks about the heads because cam design will vary depending on the heads.
The bottom line is that if you put a cam in now with stock heads, and put worked heads on later, that cam will not be the best cam for that motor anymore. Yes, the heads will give gains, but not as much as if they were matched with the proper cam.
Heads first, then cam.
The bottom line is that if you put a cam in now with stock heads, and put worked heads on later, that cam will not be the best cam for that motor anymore. Yes, the heads will give gains, but not as much as if they were matched with the proper cam.
Heads first, then cam.
10-05-2011, 09:26 PM
#43
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Although it may not be the most budget friendly approach, you should always do heads before a cam. Just talk to any cam designer, and they will tell you if you have stock heads, they'll design a cam in a certain way. If you have worked heads, they'll design a different cam. Every cam questionaire card always asks about the heads because cam design will vary depending on the heads.
The bottom line is that if you put a cam in now with stock heads, and put worked heads on later, that cam will not be the best cam for that motor anymore. Yes, the heads will give gains, but not as much as if they were matched with the proper cam.
Heads first, then cam.
The bottom line is that if you put a cam in now with stock heads, and put worked heads on later, that cam will not be the best cam for that motor anymore. Yes, the heads will give gains, but not as much as if they were matched with the proper cam.
Heads first, then cam.
Last edited by HottLS1Z; 10-06-2011 at 08:51 AM.
10-06-2011, 02:01 AM
#44
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Please dont waste your time on this.... I did this many years ago, and with bolt ons and ported 243 heads dynoed 300 rwhp on a 2004 ls1 gto. About 4000 miles later, i put in a tsp 224r cam andvthe nextvtime itvwas dynoed, it put down 393.... the cam isvyour bang for the buck. NEVER heads before cam. Learn from my experience.
This.
10-06-2011, 08:19 AM
#45
Hello,
Not to hijack your thread, but I currently have an LS6 crate engine in my O2 z28. I am like the OP and thinking about sending my heads out to AI for porting. I have shorties, slp y-pipe and Magnaflow out the back. I would like to keep my LS6 original as in OEM parts instead of adding aftermarket heads/cam setup. I am wondering if the gains with this engine be worth the $1000 for the cnc port/valve work???
Thanks guys.
Not to hijack your thread, but I currently have an LS6 crate engine in my O2 z28. I am like the OP and thinking about sending my heads out to AI for porting. I have shorties, slp y-pipe and Magnaflow out the back. I would like to keep my LS6 original as in OEM parts instead of adding aftermarket heads/cam setup. I am wondering if the gains with this engine be worth the $1000 for the cnc port/valve work???
Thanks guys.
10-06-2011, 08:23 AM
#46
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yes and match that with a cam like a 215/230 .600/.600 the thing will be beast and theres no way you could tell theres a different cam in it until you get on it. you'll definately break 400rwhp.
10-06-2011, 08:49 AM
#47
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Been deciding on where to buy the heads from as there are a couple options, and here is a question I hope someone can answer....one set this guy claims is off a C6 LS2 corvette he says one is a 243 and the other is a 799 casting. Says sometimes they came like this on some of them just not very common??? Secondly He said to run the 02+ Z06 cam with the yellow springs you need authentic Z-06 heads with the hollow stem/sodium valves otherwise one would get valve-float and need to run a bigger spring such as a 918. I have never heard this but his thinking is sound imo. What are the black springs that come on the GTO and regular C6 243 heads rated too lift wise?
10-06-2011, 09:18 AM
#48
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[QUOTE=01ssreda4;15475127]So you think that cam gained you 90hp????
Seriously... I really think you missed the point of my post. so.... I'll spell it out- The increased flow of the ported 243 heads was not optimized with the stock cam, not only was it not optimized, it may have even been detrimental as pointed out earlier because of the larger intake port volume, decrease velocity, etc, etc.
My point was that once I changed the stock cam for even a "moderate" TSP224r cam, then the potential of the heads was unlocked. If i had done a cam swap with stock heads, OBVIOUSLY my gain would be much less.
Seriously... I really think you missed the point of my post. so.... I'll spell it out- The increased flow of the ported 243 heads was not optimized with the stock cam, not only was it not optimized, it may have even been detrimental as pointed out earlier because of the larger intake port volume, decrease velocity, etc, etc.
My point was that once I changed the stock cam for even a "moderate" TSP224r cam, then the potential of the heads was unlocked. If i had done a cam swap with stock heads, OBVIOUSLY my gain would be much less.
10-09-2011, 08:45 AM
#49
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So here is my next question. I have 2 sets of heads i'm looking at. 1 set is off a Z06 so they have the light weight hollow stem sodium valves and yellow springs, the other set is off a LS2 GTO has the normal valves and black springs. Both sets have about equal miles. I can get the LS2 pair for probably 380-400 or the Z06 pair for 480. Both have been sent to machine shop and actually both heads are in ready to bolt on condition. Are the authentic Z-06 heads with the better valves worth the extra 80-100 bucks??
10-09-2011, 01:14 PM
#52
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Next issue is this, I know the base circle is smaller on the 02+ Z-06 cam and the valves are longer in the actual Z-06 LS6 heads to compensate for this and still utilize the standard stock LS1/6 pushrod. I been reading people say there are some differences when you use the LS7 lifter which last time I checked is the standard "stock replacement" for all LS engines, so what size push rod should I be looking for???
11-10-2011, 09:36 AM
#57
20whp is also optimistic for the results on a stock cam car. 10-15whp is more reasonable expectation.
Factor in cost of head bolts, head gaskets, water pump gaskets, coolant, oil, filter, and all the odds and ends plus the labor time and it is not a good bang for the buck on stock internals. You will also need at least a mail order tune as well.
I waited until I had the heads at least hand ported and shaved .010" to do mine even on a cammed car.
Factor in cost of head bolts, head gaskets, water pump gaskets, coolant, oil, filter, and all the odds and ends plus the labor time and it is not a good bang for the buck on stock internals. You will also need at least a mail order tune as well.
I waited until I had the heads at least hand ported and shaved .010" to do mine even on a cammed car.
11-10-2011, 01:30 PM
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New plan is also use the 02-04 ls6 cam maybe with some 1.8:1 rockers. I know that's a lot more then a 15rwhp gain. Id like to think that with full bolt ons should put down around 400rwhp through my m6.
11-12-2011, 08:43 AM
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Ha not really. Heads will have springs on them already, already have the cam and didn't pay much, rockers ill have for way less then a cam...not really so wasted when you consider ill be spending MAYBE a grand on everything including gaskets, bolts and lifters etc and add good HP and retain stock drivability and mpg at the same time like I want for this car.