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rod/stroke ratio

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Hi all.

I've some pistons with the following specs


84mm bore

Compression distance 1.379”

Dome height 0.035”

0.6cc positive dome

Intake valve pocket 0.120” deep x 12 degrees

Exhaust pocket 0.110” deep x 12 degrees.


I'm using an l24 block, l28 crank, l24 length rods.  The pistons were designed as a 'cheat'  gives me 2627cc.  Big valve e31 head.

This gives me a rod/stroke ratio of about 1.68 against a 1.8ish as standard.  The way I understand it this is slightly 'better'?  Or have I understood wrong?

The other engines that ran these pistons were in a rally spec cars with no engine failures.


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It's pretty amazing how little ots stocking parts there are for L engines.   There are way more obscure engines out their that you have any array of choices for.  Now almost any piston you can buy for a Chevy you would have to work at to spend much over $100 a piston unless talking exotic stuff.  My Cosworth pistons for my Subaru were less than $200 a piston and they are over the top exotic.  I understand economies of scale but certainly should be able to do better than the $1200+ I see advertised. 

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20 hours ago, madkaw said:

Care to share what pistons are from ? Or were these custom made? Deck height?


They're a custom made JE forged piston.  Deck height over standard 0.035" but with valve pockets.  with the other parts it should help make an interesting engine away from the norm.  I'm trying to put together something revvy and fun feeling.  Not and out and out HP build.

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