Need picture of L79 Piston
#1
Team Owner
Thread Starter
Need picture of L79 Piston
Anyone have a picture (top view) of a 1965 327 / 350hp piston. Also, is this the same piston as the L2166 Speed Pro on the market today.
Picture of both would be even better.
Picture of both would be even better.
#2
Team Owner
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Location: Washington Michigan
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Here's the L-79 piston (TRW L2166) - this one is +.030".
#3
Team Owner
Thread Starter
Thanks John, I have been back and forth which piston to use. The L2165 or L2166. Depending on who I talk to I get all types of answers. I understand it all come down to DCR.
I also ran across this:
KB-156.030 Hypereutectic
327ci Stock-Type Piston w/5.7'' Rods, .030'' Overbore
Piston Dia.: 4.030''
Piston Top: Flat Top, 2-Valve Reliefs
Comp Ratio: 10.3:1 w/58cc Heads, 8.4:1 w/76cc Heads
Rings: 5/64'', 5/64'', 3/16''
Priced as Each, Sold as Set
I have a set of 462 heads with screw in studs, guide plates, 2.02 / 1.60 SS Manley valves that were cut to 58 cc's. I would perfer not to buy another set of 64 cc heads. I plan to use the LT1 solid lift cam in the current 350 I have.
I also ran across this:
KB-156.030 Hypereutectic
327ci Stock-Type Piston w/5.7'' Rods, .030'' Overbore
Piston Dia.: 4.030''
Piston Top: Flat Top, 2-Valve Reliefs
Comp Ratio: 10.3:1 w/58cc Heads, 8.4:1 w/76cc Heads
Rings: 5/64'', 5/64'', 3/16''
Priced as Each, Sold as Set
I have a set of 462 heads with screw in studs, guide plates, 2.02 / 1.60 SS Manley valves that were cut to 58 cc's. I would perfer not to buy another set of 64 cc heads. I plan to use the LT1 solid lift cam in the current 350 I have.
Last edited by Mr D.; 11-05-2006 at 11:31 AM.
#5
Le Mans Master
The TRW original Forged Pistons are now manufactured by Sealed Power/Speed Pro.
Some have been slightly modified to allow for the new heads with 2.05 or 2.08 valves, but I don't know about the 327 for sure. The skirt profile has been updated which allows you to run tighter piston to bore clearance without the risk of sticking a piston. They use newer technology CNC machines that leave clearance exacty where the piston will grow when you floor the throttle. This is much better, in the old days they cut the piston round and just gave you much more clearance to allow for the expansion. The main cause of piston rattle, it also plays hell with ring seal having the piston rock in the bore all the time.
The skirts are now coated to help avoid piston scuff issues and reduce drag.
The tooling that cuts the pistons is far better than what was available in the 1960's.
If really needed I could find out what exact changes have been made to the L2166F but it would take a few days to get an answer.
The attachement shows how pistons are profiled today to allow for expansion while avoiding excess clearance.
Some have been slightly modified to allow for the new heads with 2.05 or 2.08 valves, but I don't know about the 327 for sure. The skirt profile has been updated which allows you to run tighter piston to bore clearance without the risk of sticking a piston. They use newer technology CNC machines that leave clearance exacty where the piston will grow when you floor the throttle. This is much better, in the old days they cut the piston round and just gave you much more clearance to allow for the expansion. The main cause of piston rattle, it also plays hell with ring seal having the piston rock in the bore all the time.
The skirts are now coated to help avoid piston scuff issues and reduce drag.
The tooling that cuts the pistons is far better than what was available in the 1960's.
If really needed I could find out what exact changes have been made to the L2166F but it would take a few days to get an answer.
The attachement shows how pistons are profiled today to allow for expansion while avoiding excess clearance.
#6
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#10
Le Mans Master
You would need to match the same dome and valve relief. Brand, part number, overisize and weight. The oversize would be stamped in the piston head facing the combustion chamber. Weight needs to be within a gram or two and the dome and skirt shapes and weight did change slightly over the years so be careful.
#11
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Mike, I am looking for one 30 over TRW to match the other 7. The block is standard bore but my guess would be it has to go to 30. Maybe I should send it in and have it checked first. It would be a real plus if I could keep it standard .