Ls2 Heads On Ls1 PLEASE HELP

**DeputySS** · 12-13-2007, 11:20 AM

OK here is what I've got a question about. i have a 100% stock 00 SS. my buddy has a 07 vet, he just swapped heads, and told me he thinks that his old heads (200miles on then comp. DB springs and pushrods) will be a great upgrade for my car. but this guy has more money then knowledge. and i don't know if he even knows what he is talking about. any info will be very helpful i can get the heads for $550.00 and the springs he just put in there were like $360.00. what I'm trying to do guys is get a 400 rwhp car for the least amount of money any help would be great thanks guys

**9T8W66** · 12-13-2007, 11:42 AM

If your asking if they will bolt up the answer is yes.

**DeputySS** · 12-13-2007, 12:08 PM

i know they will bolt up but will it be a performance upgrade?

**02blkws6** · 12-13-2007, 12:19 PM

Yes, they are the same casting as the LS6 heads.

**DeputySS** · 12-13-2007, 01:06 PM

what kind of performance increase would I be looking at. and would it be a good bang for the buck?

**9T8W66** · 12-13-2007, 01:21 PM

You would still need a decent Cam, LS6 Intake and Headers to be close to your HP goal.

**INMY01TA** · 12-13-2007, 01:35 PM

On a stock SS prolly see maybe 10hp. Bigger cam, headers, those numbers go up.

**0rion** · 12-13-2007, 07:07 PM

I just saw a set of these sell on a gto website for $500 with prc dual springs so even though that sounds cheap I think you could do better if you were patient and shopped around. The difference would be that you know the history of these heads and they have to be very low mileage heads. That may be worth the extra couple of bucks you'd save by looking around.

**Empatho** · 12-13-2007, 11:07 PM

make him a better offer since he has money he wont mind

**DeputySS** · 12-14-2007, 12:39 AM

what can I do to these heads to make them perform better. maybe porting rockerarms ect. and are the ls6 heads and the ls2 heads the same

**0rion** · 12-14-2007, 12:52 AM

yup, they're both 243 heads. By the time you spent the money porting those and all that you could probably buy aftermarket heads already done.

**mrr23** · 12-16-2007, 07:18 AM

Originally Posted by DeputySS

what kind of performance increase would I be looking at. and would it be a good bang for the buck?

going from your current 853 heads to the 243 heads, might get you about 20 rwhp. by the time you get new gaskets, head bolts, plugs, coolant, oil, filter, etc.., you'll be into it for around $850.00. so, it's up to you, if it would be a good bang for the buck.

**Spaz** · 12-17-2007, 10:52 AM

Originally Posted by 0rion

yup, they're both 243 heads. By the time you spent the money porting those and all that you could probably buy aftermarket heads already done.

he could port the exhuast side his self easily by following the gasket pattern and being VERY carefull... intake can also be ported...

**Firebirdjones** · 12-17-2007, 12:18 PM

I have to wonder if all the effort would even be a worthwhile swap.
Please feel free to correct me here,,,but I believe there are a few slight differences in the LS6 243 heads and the heads on the LS2 for this 07 corvette.

I may be splitting hairs here,,,but it's worth mentioning that,,,,,

The real LS6 heads from 03-04 were in fact a 243 casting,,,and had a lightweight valvetrain,,,with sodium filled exhaust valves, and a tighter combustion chamber to bump the compression on the LS6 a little higher than the previous LS1 engines.

The LS2 heads on the other hand,,,,,they do have the same port size and shape and mimic the LS6 heads in that respect,,,but I think thats where the similarities end. They have a larger combustion chamber and standard heavier valves that were found in the LS1 engine. I have to also wonder if the combustion chamber on the LS2 head was even larger yet than the LS1 head to keep the compression at reasonable levels on the larger cubic inch LS2 engine? Something to consider,,,,as this would actually lower your current compression ratio if this were true.

I recently saw a REAL pair of LS6 heads at a swap meet that came off of a 30,000 mile 03 Z06 vette,,,,they were clean and unmolested,,,,,asking price was only $350. But I passed since I figure after all the work,,,,extra money in gasket etc...(as mentioned from mrr23) I would rather just spring for a pair of CNC ported LS6 heads from the vendor of your choice,,,,not that much more coin and you get stronger results from all your effort.

It's up to you but I personally would rather have CNC'd heads brand new with the correct springs setup for the camshaft I want to use.

**Spaz** · 12-17-2007, 05:21 PM

Originally Posted by Firebirdjones

I have to wonder if all the effort would even be a worthwhile swap.
Please feel free to correct me here,,,but I believe there are a few slight differences in the LS6 243 heads and the heads on the LS2 for this 07 corvette.

I may be splitting hairs here,,,but it's worth mentioning that,,,,,

The real LS6 heads from 03-04 were in fact a 243 casting,,,and had a lightweight valvetrain,,,with sodium filled exhaust valves, and a tighter combustion chamber to bump the compression on the LS6 a little higher than the previous LS1 engines.

The LS2 heads on the other hand,,,,,they do have the same port size and shape and mimic the LS6 heads in that respect,,,but I think thats where the similarities end. They have a larger combustion chamber and standard heavier valves that were found in the LS1 engine. I have to also wonder if the combustion chamber on the LS2 head was even larger yet than the LS1 head to keep the compression at reasonable levels on the larger cubic inch LS2 engine? Something to consider,,,,as this would actually lower your current compression ratio if this were true.

I recently saw a REAL pair of LS6 heads at a swap meet that came off of a 30,000 mile 03 Z06 vette,,,,they were clean and unmolested,,,,,asking price was only $350. But I passed since I figure after all the work,,,,extra money in gasket etc...(as mentioned from mrr23) I would rather just spring for a pair of CNC ported LS6 heads from the vendor of your choice,,,,not that much more coin and you get stronger results from all your effort.

It's up to you but I personally would rather have CNC'd heads brand new with the correct springs setup for the camshaft I want to use.

LS2 head will give you a different compression ratio as they are bade for a larger CUIN block...

LS6 heads will not affect compression ration as they are make for 346 CUIN...

with that said that is the major difference in putting LS2 heads on a LS1...

**Firebirdjones** · 12-17-2007, 05:26 PM

Originally Posted by Spaz

LS2 head will give you a different compression ratio as they are bade for a larger CUIN block...

LS6 heads will not affect compression ration as they are make for 346 CUIN...

with that said that is the major difference in putting LS2 heads on a LS1...

Actually the LS6 head has a tighter/smaller combustion chamber than the LS1 head. I believe the difference is 2 or 3 CC's and it makes the LS6 compression slightly higher than the stock LS1.

It will bump the compression up if you install true LS6 heads (243) on an LS1 about .5 point or so. This won't happen with the LS2 head, and may actually go the other way,,,,as I am pretty certain the combustion chamber on the LS2 is even slightly larger than the LS1 head.

**0rion** · 12-17-2007, 05:40 PM

ok, where are you guys getting this from? to my knowledge there is no "LS2 head". They are LS6 heads which are 243 heads. Same with the exception of the sodium filled valves used on the vette. LS6 heads have a 64cc chamber and a 10.4:1 CR. Maybe I missed the LS2 head thing somewhere but to my knowledge they're the same head.

**0rion** · 12-17-2007, 05:41 PM

are you guys talking about L92 heads?

**Firebirdjones** · 12-17-2007, 06:05 PM

Here ya go,,,I broke out the cylinder head book.

Nope I am not referring to the new L92 heads,,,,,those are in a complete leage of their own requiring different intake and valve train pieces.

The LS6 head (#243) has a combustion chamber volume of exactly 64.45 CC's (most call it 64) giving the 346 ci LS6 engine a compression ratio of 10.5:1,,,or so they say.

The LS1 head casting #'s (853, 241) has a combustion chamber volume of exactly 66.67 CC's (most call it 67) giving the same 346 ci engine a compression ratio of 10.1:1.

Even flow numbers are listed on stock heads,,,,the LS6 head flowing about 30 CFM more than the LS1 head throughout the lift curve.

Now the LS2 heads,,,it's a little fuzzy,,,depending on the casting numbers,,,,because after the LS6 (243) heads were designed for the vette,,,,GM started mocking all the cylinder heads from this design,,,meaning that the intake port volume and exhaust port volumes were the same,,,and they also mimic the same shape, but casting numbers varied including the LQ4 and LQ9 truck motors,,,,which also used this same head design with LS6 style ports,,,although the chambers are much larger for this 364 ci (same size as LS2) in 01 the chamber was 71.06 CC's and this head also was found on the 01 cadillac escalade. People call these LS6 heads as well,,,,they mimic the same intake and exhaust ports,,,but in fact have a casting # of 035, and 317. But they do not have the LS6 specific valve train components,,,,hollow stem valve,,,sodium filled exhaust valves etc....did I make this even more confusing?

**0rion** · 12-17-2007, 08:33 PM

no, I knew about the 317 heads on the trucks. If I'm not mistaken that's the head people go with to lower their compression due to the larger chamber. I guess where I got confused earlier is it looked like you guys were saying the 243 heads had changed from the LS6 engines to the LS2 engines and other than the valves I wasn't aware of any change.