Carnage
Thread Starter
Le Mans Master
Joined: Feb 2009
Posts: 5,169
Likes: 199
From: Your Sister's Bedroom
They are wiseco pistons. It was a forged lq9, Ysi powered 364ci. Was happily making 900+whp before the valve head broke off. Just bad luck.
Thread Starter
Le Mans Master
Joined: Feb 2009
Posts: 5,169
Likes: 199
From: Your Sister's Bedroom
Melting Slicks
Joined: Nov 2009
Posts: 2,536
Likes: 15
Going to rebuild it back the same ?? Or plans to make some changes ??
.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Team Owner
Joined: Jan 2007
Posts: 29,063
Likes: 1,839
From: cookeville tennessee
ttt
Dam buddy hate to see the bad luck on the motor. Where you into it hard when it went. Plus what valves did the heads have in it.
More info on the block as you are able to work on her. I know you will have it back befor long even better...Robert
More info on the block as you are able to work on her. I know you will have it back befor long even better...Robert
Thread Starter
Le Mans Master
Joined: Feb 2009
Posts: 5,169
Likes: 199
From: Your Sister's Bedroom
I will be tearing the engine down soon, hoping the block, crank, and rods are ok. If its just machine work, pistons, bearings and heads it won't be to horrible. Still sucks though..
Thinking of trying a set of factory cast lsa heads on it this time around do to how cheap they are and the fact that they are a stronger casting. Can't seem to find and good info on them though as far as valve compatibility or even a definitive answer on what size the combustion chambers are. So we will see. Aftermarket heads simply are not in his budget.
AKA "The CLOWN"
Joined: Feb 2010
Posts: 6,261
Likes: 13
From: Chicago South Suburbs
More pictures will follow. The engine belongs to a good friend of mine, pulled it out of his car yesterday. The valve let go towards the end of a day of road racing at road America. The heads were worked over factory 317 castings and the valves were Manley stainless covered by patriot springs and pushed by crane gold adjustable rockers. None of the other valves show any signs of loss of valve control or float. Looks like nothing more than valve failure to me at this point, perhaps do to the extreme heat generated with a engine that powerful in a road racing application.
I will be tearing the engine down soon, hoping the block, crank, and rods are ok. If its just machine work, pistons, bearings and heads it won't be to horrible. Still sucks though..
Thinking of trying a set of factory cast lsa heads on it this time around do to how cheap they are and the fact that they are a stronger casting. Can't seem to find and good info on them though as far as valve compatibility or even a definitive answer on what size the combustion chambers are. So we will see. Aftermarket heads simply are not in his budget.
I will be tearing the engine down soon, hoping the block, crank, and rods are ok. If its just machine work, pistons, bearings and heads it won't be to horrible. Still sucks though..
Thinking of trying a set of factory cast lsa heads on it this time around do to how cheap they are and the fact that they are a stronger casting. Can't seem to find and good info on them though as far as valve compatibility or even a definitive answer on what size the combustion chambers are. So we will see. Aftermarket heads simply are not in his budget.
Thread Starter
Le Mans Master
Joined: Feb 2009
Posts: 5,169
Likes: 199
From: Your Sister's Bedroom
If I can find out what the chamber size is and what valves they use I can proceed. I am unsure If aftermarket ls3/l92 valves will work in them and Manley and rev do not list a part number specifically for that head. If the spring set from the 243/317 heads will work that will make them even cheaper as I have a lot of prc and patriot stuff laying around already.
AKA "The CLOWN"
Joined: Feb 2010
Posts: 6,261
Likes: 13
From: Chicago South Suburbs
I tried to contact him actually, I get he is busy though. See I get conflicting info on the chambers. I hear 68 but I also hear 70. I also hear that people don't recommend shaving them but I personally cannot see why that is a issue. I have some homework to do on them still, but I wouldn't mind giving them a shot. I need to be able to get the compression up around 10.0-10.2 though, it was a 9.5 engine, not doing that again.
If I can find out what the chamber size is and what valves they use I can proceed. I am unsure If aftermarket ls3/l92 valves will work in them and Manley and rev do not list a part number specifically for that head. If the spring set from the 243/317 heads will work that will make them even cheaper as I have a lot of prc and patriot stuff laying around already.
If I can find out what the chamber size is and what valves they use I can proceed. I am unsure If aftermarket ls3/l92 valves will work in them and Manley and rev do not list a part number specifically for that head. If the spring set from the 243/317 heads will work that will make them even cheaper as I have a lot of prc and patriot stuff laying around already.
Drifting
Joined: Jan 2008
Posts: 1,927
Likes: 0
From: Edmond Oklahoma
More pictures will follow. The engine belongs to a good friend of mine, pulled it out of his car yesterday. The valve let go towards the end of a day of road racing at road America. The heads were worked over factory 317 castings and the valves were Manley stainless covered by patriot springs and pushed by crane gold adjustable rockers. None of the other valves show any signs of loss of valve control or float. Looks like nothing more than valve failure to me at this point, perhaps do to the extreme heat generated with a engine that powerful in a road racing application.
I will be tearing the engine down soon, hoping the block, crank, and rods are ok. If its just machine work, pistons, bearings and heads it won't be to horrible. Still sucks though..
Thinking of trying a set of factory cast lsa heads on it this time around do to how cheap they are and the fact that they are a stronger casting. Can't seem to find and good info on them though as far as valve compatibility or even a definitive answer on what size the combustion chambers are. So we will see. Aftermarket heads simply are not in his budget.
I will be tearing the engine down soon, hoping the block, crank, and rods are ok. If its just machine work, pistons, bearings and heads it won't be to horrible. Still sucks though..
Thinking of trying a set of factory cast lsa heads on it this time around do to how cheap they are and the fact that they are a stronger casting. Can't seem to find and good info on them though as far as valve compatibility or even a definitive answer on what size the combustion chambers are. So we will see. Aftermarket heads simply are not in his budget.
Likelihood of it being the heat, consider going to inconel exhaust valves on that motor. They aren't cheap but they are worth it.
The lsa heads require a ls3 type manifold don't they? I'm not real sure. I'd add up the cost of the swap and consider all head options that don't require any changes other than the head.
Stock 317s *stock* will take a beating and make good power so I'd keep them on the table when looking at lsa heads too. (put inconel exhaust valves in them) Basically, I'd use whichever ones fit the amount of $ I want to spend because you can make them perform equally.
Former Vendor
Joined: Jul 2010
Posts: 4,504
Likes: 4
From: Waterloo Ontario
I tried to contact him actually, I get he is busy though. See I get conflicting info on the chambers. I hear 68 but I also hear 70. I also hear that people don't recommend shaving them but I personally cannot see why that is a issue. I have some homework to do on them still, but I wouldn't mind giving them a shot. I need to be able to get the compression up around 10.0-10.2 though, it was a 9.5 engine, not doing that again.
If I can find out what the chamber size is and what valves they use I can proceed. I am unsure If aftermarket ls3/l92 valves will work in them and Manley and rev do not list a part number specifically for that head. If the spring set from the 243/317 heads will work that will make them even cheaper as I have a lot of prc and patriot stuff laying around already.
If I can find out what the chamber size is and what valves they use I can proceed. I am unsure If aftermarket ls3/l92 valves will work in them and Manley and rev do not list a part number specifically for that head. If the spring set from the 243/317 heads will work that will make them even cheaper as I have a lot of prc and patriot stuff laying around already.
I personally would not mill them, the more material the better.
I would use the factory issue hollow stem intake valves-there's no worries about them breaking. The exhaust valve has all pressure on them-which is exactly what broke on your setup.
The lighter intake valves is a huge plus on big power boosted setups.
The spring sets from the LS1 heads swap right over to the LS3 stuff.
I would worry about the 9.5 CR, especially if your boost level is double digits. You can compensate that easily with a cam change.
That's the other nice thing about the LS3/LSA heads-you don't need much of a cam to make some good power with them.
I am considering getting Charlie@RPM run his CNC port program on a set of heads for me.
Thread Starter
Le Mans Master
Joined: Feb 2009
Posts: 5,169
Likes: 199
From: Your Sister's Bedroom
The car made about 18lbs at 6500rpm and close to 20 at 7000. The engine was a 9.5 comp and the cam was speced out by ecs. The combo seemed to work great but I personally feel the 9.5 comp made it a bit lazy out of boost so this time around I was going to try to get it up around 10. I am open to discussion as to why I shouldn't though. I feel the higher comp will help with responsiveness and even fuel mileage. Isn't your engine in the 10s?
Really appreciate the info Arun.
Really appreciate the info Arun.
From what I have seen, the heads are 68-70cc, the chamber is nice and smooth-almost like the anti-detonation work done on my TFS 245's.
I personally would not mill them, the more material the better.
I would use the factory issue hollow stem intake valves-there's no worries about them breaking. The exhaust valve has all pressure on them-which is exactly what broke on your setup.
The lighter intake valves is a huge plus on big power boosted setups.
The spring sets from the LS1 heads swap right over to the LS3 stuff.
I would worry about the 9.5 CR, especially if your boost level is double digits. You can compensate that easily with a cam change.
That's the other nice thing about the LS3/LSA heads-you don't need much of a cam to make some good power with them.
I am considering getting Charlie@RPM run his CNC port program on a set of heads for me.
I personally would not mill them, the more material the better.
I would use the factory issue hollow stem intake valves-there's no worries about them breaking. The exhaust valve has all pressure on them-which is exactly what broke on your setup.
The lighter intake valves is a huge plus on big power boosted setups.
The spring sets from the LS1 heads swap right over to the LS3 stuff.
I would worry about the 9.5 CR, especially if your boost level is double digits. You can compensate that easily with a cam change.
That's the other nice thing about the LS3/LSA heads-you don't need much of a cam to make some good power with them.
I am considering getting Charlie@RPM run his CNC port program on a set of heads for me.
Thread Starter
Le Mans Master
Joined: Feb 2009
Posts: 5,169
Likes: 199
From: Your Sister's Bedroom
I agree with you. Ls3 intakes are cheap though, have a ported ls2 he can sell. Inconel exhaust valves are a must this time around for the exhaust side. Arun seems to feel the factory hollow stem lsa intake valves are the way to go though.
As I want to increase compression this time 317s are no longer a option and I'm interested in this lsa head, it looks like an amazing factory part.
As I want to increase compression this time 317s are no longer a option and I'm interested in this lsa head, it looks like an amazing factory part.
The heat is what I was thinking but didn't want to jump to conclusion. Now that you mention the rest not showing any signs of float then it seems more plausible. How many miles/track trips were on the springs and did you test them all? Might be worth testing them in order that they were running just to rule out a weak spring.
Likelihood of it being the heat, consider going to inconel exhaust valves on that motor. They aren't cheap but they are worth it.
The lsa heads require a ls3 type manifold don't they? I'm not real sure. I'd add up the cost of the swap and consider all head options that don't require any changes other than the head.
Stock 317s *stock* will take a beating and make good power so I'd keep them on the table when looking at lsa heads too. (put inconel exhaust valves in them) Basically, I'd use whichever ones fit the amount of $ I want to spend because you can make them perform equally.
Likelihood of it being the heat, consider going to inconel exhaust valves on that motor. They aren't cheap but they are worth it.
The lsa heads require a ls3 type manifold don't they? I'm not real sure. I'd add up the cost of the swap and consider all head options that don't require any changes other than the head.
Stock 317s *stock* will take a beating and make good power so I'd keep them on the table when looking at lsa heads too. (put inconel exhaust valves in them) Basically, I'd use whichever ones fit the amount of $ I want to spend because you can make them perform equally.
Former Vendor
Joined: Jul 2010
Posts: 4,504
Likes: 4
From: Waterloo Ontario
The car made about 18lbs at 6500rpm and close to 20 at 7000. The engine was a 9.5 comp and the cam was speced out by ecs. The combo seemed to work great but I personally feel the 9.5 comp made it a bit lazy out of boost so this time around I was going to try to get it up around 10. I am open to discussion as to why I shouldn't though. I feel the higher comp will help with responsiveness and even fuel mileage. Isn't your engine in the 10s?
Really appreciate the info Arun.
Really appreciate the info Arun.
These are all 4" stroke motors though.
From 9.5 to 10.1-there's no discernible difference.
Thread Starter
Le Mans Master
Joined: Feb 2009
Posts: 5,169
Likes: 199
From: Your Sister's Bedroom
Does anyone know if the lsa head has a factory inconel exhaust valve like the ly6 head? If that is the case I believe Arun could be dead on with just changing the springs and letting them eat.