Big boost with rectangular port heads? Step inside
#22
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automagic seems to be doing just fine running cathedrals. I think on your boost levels you are putting out more power than he is though lol
#25
FormerVendor
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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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Pro Stock John (09-07-2021)
#32
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Any updates on this? I was all gung-ho for going to a ls3 top end on my 408 build for the turbo camaro... now im starting second guess it. I had hoped to used the 823/821 heads, but if you guys are having issues with the materials being weak what do you recommend?
Im currently forged ls1, ls6 intake, z06 cam, 317s, 20psi rear mount 72mm, 6 speed. 600hp/700trq
I have a lq4 sitting in the garage i wanted to make a 408, 823s, ls3 intake, mild cam, same turbo till i can upgrade to a 76/80.
Any advise? Its a daily driver car, so not looking to go too crazy just want to pick up the down low power the current setup is lacking... and hopefully an overall increase of my curve.
Im currently forged ls1, ls6 intake, z06 cam, 317s, 20psi rear mount 72mm, 6 speed. 600hp/700trq
I have a lq4 sitting in the garage i wanted to make a 408, 823s, ls3 intake, mild cam, same turbo till i can upgrade to a 76/80.
Any advise? Its a daily driver car, so not looking to go too crazy just want to pick up the down low power the current setup is lacking... and hopefully an overall increase of my curve.
#33
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Any updates on this? I was all gung-ho for going to a ls3 top end on my 408 build for the turbo camaro... now im starting second guess it. I had hoped to used the 823/821 heads, but if you guys are having issues with the materials being weak what do you recommend?
Im currently forged ls1, ls6 intake, z06 cam, 317s, 20psi rear mount 72mm, 6 speed. 600hp/700trq
I have a lq4 sitting in the garage i wanted to make a 408, 823s, ls3 intake, mild cam, same turbo till i can upgrade to a 76/80.
Any advise? Its a daily driver car, so not looking to go too crazy just want to pick up the down low power the current setup is lacking... and hopefully an overall increase of my curve.
Im currently forged ls1, ls6 intake, z06 cam, 317s, 20psi rear mount 72mm, 6 speed. 600hp/700trq
I have a lq4 sitting in the garage i wanted to make a 408, 823s, ls3 intake, mild cam, same turbo till i can upgrade to a 76/80.
Any advise? Its a daily driver car, so not looking to go too crazy just want to pick up the down low power the current setup is lacking... and hopefully an overall increase of my curve.
#34
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Some foks claim the wing in the intake port stalls the head but I find that really, really hard to beleive.
If it did why the hell did GM put it there? Especially on a boosted aplication?
There are some things the flow bench won't tell you-for the others just turn up the boost.
I'm damn near tempted to pull my TFS 245's to try out as set of these heads.
If it did why the hell did GM put it there? Especially on a boosted aplication?
There are some things the flow bench won't tell you-for the others just turn up the boost.
I'm damn near tempted to pull my TFS 245's to try out as set of these heads.
#35
9 Second Club
iTrader: (31)
Some foks claim the wing in the intake port stalls the head but I find that really, really hard to beleive.
If it did why the hell did GM put it there? Especially on a boosted aplication?
There are some things the flow bench won't tell you-for the others just turn up the boost.
I'm damn near tempted to pull my TFS 245's to try out as set of these heads.
If it did why the hell did GM put it there? Especially on a boosted aplication?
There are some things the flow bench won't tell you-for the others just turn up the boost.
I'm damn near tempted to pull my TFS 245's to try out as set of these heads.
Wanna trade?
#39
I know on Richard's program with minimum deck milling, just enough to give a good deck surface
I was around 74cc on my lsa set, cant remember how much less the stock chamber was
I was around 74cc on my lsa set, cant remember how much less the stock chamber was