I did some LSA head testing!
For those not venturing over to the other thread-
Got everything cut, Ill post pics sometime soon.
241 Couldnt find a 317 in my trash pile.... I can cut one as soon as I get one. thought I had some, but I guess the scrap man got them first!
821 LS3 OEM Vette casting
8452 OEM LS7 casting
863 LSA casting
In summary:
Pics coming soon.
Louis
241 Couldnt find a 317 in my trash pile.... I can cut one as soon as I get one. thought I had some, but I guess the scrap man got them first!
- material was OK
- Deck was roughly .400 and .430 in the two spots I cut
- Bosses for head bolts were not re-inforced
821 LS3 OEM Vette casting
- Material machined very easily. Almost too easy. It was the softest of the bunch.
- Deck was .400 everywhere I measured it.
- No bolt reinforcements.
8452 OEM LS7 casting
- Material was nice. 2nd toughest of the group of 4.
- deck was again ~ .400
- bolt reinforcements present!
863 LSA casting
- Deck thickness was .400-.430
- material was the toughest of the bunch! I had to change tools and actually use a good end mill
- bolt holes have reinforcement ribs.
- area above the exhaust side of the chamber has a different appearance compared to LS1 241 casting.
In summary:
- LSA heads had the best material
- virtually no difference in deck thickness
- LS7 and LSA contain ribs around the bolt holes in the water jackets
- LS3 cut like butter, easier than the 241.
Pics coming soon.
Louis
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That is a really good point I never thought of. Would that matter so much once it is pressurized though? It seems deep enough in runner that it could do its job the same but it makes sense that maybe it isnt. Now you got me thinking.
It would be interesting to see the wings benefit vs not having it. I would imagine it could be at least another 40 cfm out of the head being fully ported as well.
Awesome comparison on the different heads also. Thank you for taking the time to do that for us. I have always wondered myself but lack a pile of old cylinder heads to cut up lol.
It would be interesting to see the wings benefit vs not having it. I would imagine it could be at least another 40 cfm out of the head being fully ported as well.
Awesome comparison on the different heads also. Thank you for taking the time to do that for us. I have always wondered myself but lack a pile of old cylinder heads to cut up lol.
Yes. I had a Vic Jr. on mine 1st but being in a 4th gen I ran into elbow fitment issues so instead of hacking my car apart or putting some God awful restrictive elbow on it I sold it off for a LS3 intake.
You guys are letting the cat out of the bag on these heads lol. I been running them on a turbo setup all year and they make killer power. IMO for the $$ there is not a better boost head. I see these replacing the 317 castings for budget 6.0 builds very soon. Square port motors spool turbos extremley hard too.
As far as the deck thickness I am almost certain they are thicker than L92/LS3 heads. They are made of better grade aluminium and are rotocast (spun) as they are cooling. The wing serves some function of fuel mixture suspension and even distribution across the combustion chamber under pressure as well. You may find some more flow by removing it but these seem to make very useable power as is I would hate to even touch them. I am sure alot of GM money and time was spent developing that wing.
They also have no casting # in the usual spot so people dont necessarily know what you are running which is cool.
I know alot of the hardcore cathedral guys will poopoo on rectangular port heads saying they dont rev blah blah blah. The big valve may be shrouded. Or they have no velocity. My response is. May have a slight point N.A but how can you mess with a 260cc as cast intake runner pressurized? It flat out moves more air.
As far as the deck thickness I am almost certain they are thicker than L92/LS3 heads. They are made of better grade aluminium and are rotocast (spun) as they are cooling. The wing serves some function of fuel mixture suspension and even distribution across the combustion chamber under pressure as well. You may find some more flow by removing it but these seem to make very useable power as is I would hate to even touch them. I am sure alot of GM money and time was spent developing that wing.
They also have no casting # in the usual spot so people dont necessarily know what you are running which is cool.
I know alot of the hardcore cathedral guys will poopoo on rectangular port heads saying they dont rev blah blah blah. The big valve may be shrouded. Or they have no velocity. My response is. May have a slight point N.A but how can you mess with a 260cc as cast intake runner pressurized? It flat out moves more air.
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Verdad Gallardo I would rather not say exact because of people knowing who I am on here but 700 wheel on the wastegate is very accurate. I am running LS9 headgaskets/ARP bolts on a stock Gen4 LS2 shorblock. Ls9 camshaft as well.
Another interesting thing about this thread was the flow numbers on the LSA heads seem to match up nice with the LS9 camshafts 550" lift lobes. They dont seem to pick much up after 550" and certainly not after 600"
Someone else on the ctsv owners forum flowed as cast LSA heads showing the 550" number I believe it was 287cfm and by 600" lift it only picked up 3 cfm picking up to 290cfm. I know it is under pressure and all rules change from a flow bench but that does say something.
Someone else on the ctsv owners forum flowed as cast LSA heads showing the 550" number I believe it was 287cfm and by 600" lift it only picked up 3 cfm picking up to 290cfm. I know it is under pressure and all rules change from a flow bench but that does say something.
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I sold my whole engine combo from top to bottom and was going to take a break this season when a customer made me an offer I couldn't refuse.
I'm going to build him a 365 cube LSA head combo and run my 10 rib YSi setup.
It will go in my car to get thoroughy tested, I don't see any issue with me making 950-1050 rwhp with this setup with the YSi pushing 25-28 psi.
I have already started collecting the engine parts-I have a new LS2 block and some Wiseco's. K1 is sending me some H-beam rods and a 4340 stock stroke crank.
Once I get the heads back from getting CNC's I'm going to fill them with some hollow stem intakes-stock exhausts and some BTRacing .660 lift springs. Add some comp trunions to the factory LS3 rockers and my top end is done.
Since these heards have such huge runners I all ready have a cam in mind that actually idle and drive like a kitten. Which is one requirement my customer had-big power-but very streetable.
Now with the stroke gone-I should be able to launch my car in 1st and get my 60's down to the low 1.3's and run some 8.7's.
Well call me crazy but these LSA heads are what I'm going to be trying out over my tried and true TFS 235's and 245's this season.
I'm going to build him a 365 cube LSA head combo and run my 10 rib YSi setup.
It will go in my car to get thoroughy tested, I don't see any issue with me making 950-1050 rwhp with this setup with the YSi pushing 25-28 psi.
I have already started collecting the engine parts-I have a new LS2 block and some Wiseco's. K1 is sending me some H-beam rods and a 4340 stock stroke crank.
Once I get the heads back from getting CNC's I'm going to fill them with some hollow stem intakes-stock exhausts and some BTRacing .660 lift springs. Add some comp trunions to the factory LS3 rockers and my top end is done.
Since these heards have such huge runners I all ready have a cam in mind that actually idle and drive like a kitten. Which is one requirement my customer had-big power-but very streetable.
I'm going to build him a 365 cube LSA head combo and run my 10 rib YSi setup.
It will go in my car to get thoroughy tested, I don't see any issue with me making 950-1050 rwhp with this setup with the YSi pushing 25-28 psi.
I have already started collecting the engine parts-I have a new LS2 block and some Wiseco's. K1 is sending me some H-beam rods and a 4340 stock stroke crank.
Once I get the heads back from getting CNC's I'm going to fill them with some hollow stem intakes-stock exhausts and some BTRacing .660 lift springs. Add some comp trunions to the factory LS3 rockers and my top end is done.
Since these heards have such huge runners I all ready have a cam in mind that actually idle and drive like a kitten. Which is one requirement my customer had-big power-but very streetable.
Would you run that cam with a set of stock LSA heads? I think I may run them un-ported for a while.
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The extra lift won't hurt a thing. And who knows how the heads will work-hell that wing may work even better than GM intended with the extra boost-that's the something the flow bench cannot simulate.
Ls3 intake works just fine. I had to grind off a little tab of plastic on the passenger side of the intake to make it fit on the LSA heads. It is a little location dowell that the LSA heads do not have in that spot. You will see once you set it on.
I ran these LSA heads with LS9 cam in my old 2002 Camaro. I am sure it was making over 1000hp at the boost level I was at and had no problems with them. I plan on making 1200+hp on these heads again just stuck on what intake to run. Might just run a stocker for now.
When are you going to get the heads back from getting worked? I definitely want to see some numbers on them because I need to order a set of heads.