Author Topic: 302 Trans Am pistons  (Read 599 times)

GMS

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302 Trans Am pistons
« on: February 17, 2018, 06:39:39 PM »
All
I have came across a piston/rod combo, that I would like to learn more about. They are a 5.7 sm. journal BRC rod, 4"bore piston using single ring and single lock on piston pin. Only markings on pistons are casting of 51010 on inside. Supposedly they are road racing 302. that have been packed away for years.
Compression distance measures closer to 350 piston or possibly a 6" rod 302....? not the 5.7 with them
Curious if anyone remembers this, or a similar combo used in any first or second gen. LT1 trans am racing.

Thanks in advance.

1109RWHP

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Re: 302 Trans Am pistons
« Reply #1 on: February 17, 2018, 10:24:15 PM »
I would think it would be unusual to road race with aluminum connecting rods.

GMS

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Re: 302 Trans Am pistons
« Reply #2 on: February 18, 2018, 12:04:30 AM »
I thought the same about using one ring on a long road course race

Jon Mello

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Re: 302 Trans Am pistons
« Reply #3 on: February 18, 2018, 03:29:28 AM »
I'm with 1109.  An aluminum rod would indicate a drag racing intent rather than road racing, in my opinion.
Jon Mello
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Re: 302 Trans Am pistons
« Reply #4 on: May 05, 2018, 07:17:57 AM »
I'm with 1109.  An aluminum rod would indicate a drag racing intent rather than road racing, in my opinion.
The weight reductions are all for acceleration.
X2 on drag racing for the AL rods it also applies to the single ring pack... we used gapless rings & you don't really need oil control in full throttle acceleration runs... it's the decel where you get oil blow by from Crank case pressure. 

FWIW AL rods stretch when running, every AL ROD engine I have set up the pistons are set below deck...
I do not remember if the rods were short or if the compression height of the piston was shorter...

I have wanted to build a 6.125 or 6.25" rodded 302 run a callies crank and carillo rods - narrow pins -  for a while just to see what I could get out of a 12:1 solid roller, 302 with good heads. .
 
James
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