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so should i use the .040 pistons i have now or go std bore? or .030 or .060 to get some more cubes out of it?
 

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They sell the Dart block in a 4.125 bore ready to go.It can still be bored another .060 to 4.185.The R302 is done at 4.125.There is *two* standard bores for the Dart,4.00 and 4.125. :D

http://flatlanderracing.com/dartfordblocks.html

Why pay to bore the block out,when you can buy one already done?

The only drawback is you would need custom pistons.

OTOH...If the old pistons are worth it, get the standard bore and bore it to 4.040 ;)
 

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I'd definitly go for the 4.125 bore Dart block for some more cubes. Sure wont hurt far as unshrouding the valves either. :) Just will cost some for the custom pistons. Standard stroke 302 would be 320.7ci or a standard stroke 351 would be 374.2 ci with a 4.125 bore.

Billy
 

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First, what are your plans for the engine? If you're not building this for a class that is cube limited, definitely go with the larger 4.125 bore as it will give you more cubes and better breathing capacity with the right heads. The block comes that size and eliminates more machine work on the new block. I think it would be better to sell your pistons and put the money toward custom pistons for your combination (4.125" bore is a common size so pistons are readily available). If you go with the 8.2 deck block, the 4.125" bore and a nice 3.4" or 3.25" stroker crank would be the best choices in my opinion. It all comes down to what you want out of the engine, but if you're buying that excellent block, I would recommend you get the most for your money (read larger cubes). Just make sure you match the heads, intake, and cam to the inches you choose. Good luck on your project. -James
--by the way, I'm building a 351W stroker using an SVO 9.5 block (the Dart wasn't ready when I ordered) using a 4.125" bore and 4.00"-- 427 inches!
 

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'84 LTD LX said:
They sell the Dart block in a 4.125 bore ready to go.It can still be bored another .060 to 4.185.The R302 is done at 4.125.There is *two* standard bores for the Dart,4.00 and 4.125. :D
My engine builder told me they had gone more than .125 over on R302's :idunno: Was he off his rocker?

I like the idea of one of the Dart 4.125 blocks Brad ;)
 

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Bobo said:
My engine builder told me they had gone more than .125 over on R302's :idunno: Was he off his rocker?

I like the idea of one of the Dart 4.125 blocks Brad ;)
The most Ford recomends is a 4.125 bore on the R302.I'm sure there are a few that can go further.A freind of mine has a 4.080 bore A4 block,these are only good for a 4.060 bore.;)

There seem to be plenty of 308s and 310s built out of the 87-up roller blocks,these blocks are rated to a 4.030 bore.

The 4.125 bore Dart is a better deal,almost fully machined and can be bored easily .060 more than the R302 (Who knows? It could go more)

OTOH...The R302 might come down in price as its not the 'King of the Hill' anymore.
 

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Good point about people going past the "recomended" bore LTD. But I don't think my R302 motor coulda even been king of an anthill :lol: But I may have more fun with it yet ;)
 
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