Pistons for LH6
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Pistons for LH6 I am really new to this LS space and trying to figure out what all fits where. I have an LH6 block with 799 heads but it came with no pistons only rods. On the factory spec sheet it says the motor came with flat top pistons. But i came across a set of dished top pistons and just wanted to make sure they will work okay.. from what ive read on other threads they will but there applications are different or different goals so i just wanted to ask specifically for my engine.
The engine has AFM but i am going to delete it and no VVT
Thanks for any advice !
The engine has AFM but i am going to delete it and no VVT
Thanks for any advice !
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If the pistons are dished, and for your bore size, they most likely are for a Gen III 5.3 that came with 706 heads which have smaller chambers.
799 chambers are a bit larger, so using these pistons with 799 heads will lower compression somewhat.
799 chambers are a bit larger, so using these pistons with 799 heads will lower compression somewhat.
If they're for use with 6.098" LS rods, it's designed for the LS 3.78" bore and uses 0.943" wrist pins I don't see why not. It may be that they're 0.945" pins and you'll have to hone the end of the rods for them to work.
You can use a dish set of pistons but there is about -8cc dish in them. Your going to lower the compression on that motor to almost 9.1:1 . It's not going to be as peppy as the stock set up.
You can buy replacement pistons from Engine Tech, Speed Pro, Silv-O-Lite, Mursa, Nippon and few other companies.
You can buy replacement pistons from Engine Tech, Speed Pro, Silv-O-Lite, Mursa, Nippon and few other companies.
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I've heard of this practice on other engines, but not the LS.
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A Smokie Reply. OK, I spoke to one Yunick about "pin-offset".
He too agreed with me and added that this method was common in early NASCAR engines.
A "backward" installed Offset Pin Piston will ADD Dynamic Compression and the engine Torque Range will have a HIGHER peak.
Thus a "poor man's" LR engine.
The piston will remain higher in the cylinder as the crankshaft turns after combustion.
This effect allows for smaller intake port sizes.
Lance
He too agreed with me and added that this method was common in early NASCAR engines.
A "backward" installed Offset Pin Piston will ADD Dynamic Compression and the engine Torque Range will have a HIGHER peak.
Thus a "poor man's" LR engine.
The piston will remain higher in the cylinder as the crankshaft turns after combustion.
This effect allows for smaller intake port sizes.
Lance
The pin offset is .064 in the OEM LS pistons I’ve measured. This might vary with aftermarket offerings.
OK, I spoke to one Yunick about "pin-offset".
He too agreed with me and added that this method was common in early NASCAR engines.
A "backward" installed Offset Pin Piston will ADD Dynamic Compression and the engine Torque Range will have a HIGHER peak.
Thus a "poor man's" LR engine.
The piston will remain higher in the cylinder as the crankshaft turns after combustion.
This effect allows for smaller intake port sizes.
Lance
He too agreed with me and added that this method was common in early NASCAR engines.
A "backward" installed Offset Pin Piston will ADD Dynamic Compression and the engine Torque Range will have a HIGHER peak.
Thus a "poor man's" LR engine.
The piston will remain higher in the cylinder as the crankshaft turns after combustion.
This effect allows for smaller intake port sizes.
Lance
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Best Kept Secrets Best Kept, the location of Smoky's Garage, and Secret address/contact information.
Yes, when I spoke to him, he was surprised.
He did this because he could NEVER get work finished due to interruptions!
Yes, when I spoke to him, he was surprised.
He did this because he could NEVER get work finished due to interruptions!
We were a R&D shop for NASCAR teams, back when the teams farmed out their engine work. My boss and Smokey were great friends, so the phone conversations were regular. I was hoping to get to meet him, but I never did. You are correct about the interruptions…he hated them.
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We were a R&D shop for NASCAR teams, back when the teams farmed out their engine work. My boss and Smokey were great friends, so the phone conversations were regular. I was hoping to get to meet him, but I never did. You are correct about the interruptions…he hated them.