1970 lt1 deuce pistons

[BCreekDave]

There was a Speed-pro (TRW forged) piston available at one time in 40 over:

https://www.summitracing.com/parts/slp-lw2304f40

It was a lightweight forging, hence the LW.

I looked for them but could never find any available.

[novadude]

I can't imagine any 48 yr old block having absolutely perfect 4.000" bores without taper, etc. If you really want to do it right, I would suggest going 0.030" over and using any aftermarket LT1-style piston.

I guess you could get away with stock pistons and standard bore if you have a really great block, only want to idle onto a show field, and don't mind loose piston-to-bore clearance. These cars were driven hard when new, and it's pretty likely that they will ALL have some bore wear.

[rszmjt]

Originally Posted by novadude

I can't imagine any 48 yr old block having absolutely perfect 4.000" bores without taper, etc. If you really want to do it right, I would suggest going 0.030" over and using any aftermarket LT1-style piston.

I guess you could get away with stock pistons and standard bore if you have a really great block, only want to idle onto a show field, and don't mind loose piston-to-bore clearance. These cars were driven hard when new, and it's pretty likely that they will ALL have some bore wear.

I agree completly, I have also gotten away with coating the piston skirts to tighten up the bore clearance somewhat if a budget is a concern? The L2304 can be run up to .005 ( IMO ) without skirt clatter when cold, let’s face it lots of these collector cars don’t see a lot of mileage every year, especially if you live in climate that has snow for up to 6 months like we do, or have your stuff in indefinite storage , LOL like me.

FWIW - the new version of the L2304 with coated skirts is no where near as nice as the older versions, not only is the pin 18 grams heavier, they are usually all over the place on pin fit, I just used a set of .060 and they were anywhere from .0001 tenth to .0006 tenths clearance. Plus the domes are almost a cast type rough finish. They L2304 domes are .200 give or take, the current L2210 - 302 piston comes with a .430 dome and must be machined to around .200 ( depending on chamber cc and head gasket parameters ) to achieve the original 11 to 1 compression ratio.

Hope this helps.

[NorCam]

Originally Posted by BCreekDave

There was a Speed-pro (TRW forged) piston available at one time in 40 over:

https://www.summitracing.com/parts/slp-lw2304f40

It was a lightweight forging, hence the LW.

I looked for them but could never find any available.

Here's the PDF showing all the pistons from Speed Pro including the L2304F at .040. Not sure they still make them but they are still listed.

I ordered the .430 domes last year and had them milled down for 11:1 compression in my 302.