Ring gap
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Ring gap
What should the ring gap be on these?
4.155 Bore Hyper Pistons / Speed Pro
Rings are Sealed Power Performance Piston Ring Sets
Piston Rings, Moly, 4.155 in. Bore, 5/ 64 in., 5/ 64 in., 3/ 16 in. Thickness, for 8-Cylinder,
http://store.summitracing.com/egnsea...ts=false&N=115
4.155 Bore Hyper Pistons / Speed Pro
Rings are Sealed Power Performance Piston Ring Sets
Piston Rings, Moly, 4.155 in. Bore, 5/ 64 in., 5/ 64 in., 3/ 16 in. Thickness, for 8-Cylinder,
http://store.summitracing.com/egnsea...ts=false&N=115
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Does Speed Pro have a recommendation? Keith Black would like to see the top ring gapped in the .027" to .033" range for their hypereutectic pistons, depending in usage. Are there any shiny spots on the ends of the rings to indicate that the gap closed up and the ends butted together?
RACE ON!!!
RACE ON!!!
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Originally Posted by CFI-EFI
Does Speed Pro have a recommendation? Keith Black would like to see the top ring gapped in the .027" to .033" range for their hypereutectic pistons, depending in usage. Are there any shiny spots on the ends of the rings to indicate that the gap closed up and the ends butted together?
RACE ON!!!
RACE ON!!!
No I could not find any spots that show butting. I think 8degrees abse timing + 42 degrees of advance + 87 octane was the killer.
On the Ring gap, Speed Pro says to use the factory ring gaps.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
No butting is good except, if it had, and there were evidence, it could help answer some questions.
It is difficult to observe total timing with a light, as back in the precomputer days, but if you have a scanner and/or a way to read the chip, then I agree the timing was excessive... for any octane. Was that a goof up or a not so wise decision (mistake)?
I'd stick with Speed Pro's advice on the ring gap.
RACE ON!!!
It is difficult to observe total timing with a light, as back in the precomputer days, but if you have a scanner and/or a way to read the chip, then I agree the timing was excessive... for any octane. Was that a goof up or a not so wise decision (mistake)?
I'd stick with Speed Pro's advice on the ring gap.
RACE ON!!!
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Originally Posted by CFI-EFI
Was that a goof up or a not so wise decision (mistake)?
I'd stick with Speed Pro's advice on the ring gap.
RACE ON!!!
I'd stick with Speed Pro's advice on the ring gap.
RACE ON!!!
Timing was set at 8 degrees, max in the chip was 41.5, chip was programmed by someone else, which will remain nameless
