Pistons/rods for '85 block??

[Turbo-Archie]

Pistons/rods/gaskets for '85 block???

I have been searching this site for over a week now and stumbled across some really good stuff.

This has not really been addressed though. I have a 140 '85 block and need to order .030 pistons. I'm leaning towards diamonds with a 1.850 DH. My block has been cut and my shop will check DH but my guess is around 9.550.


Now, I can go to a thiner gasket but the pistons will be in the hole -.040.

I also wanted to use stock rods bushed for floating pins.

I guess my question is, should I have my shop off set the bushing to lengthen the rod to 6" to get a 0 deck??
I really don’t want to buy 6” rods.


What combo works on the older blocks in a high HP set up.

Thanks!!

.

 

[thadeal4real]

I also wanted to use stock rods bushed for floating pins.

I guess my question is, should I have my shop off set the bushing to lengthen the rod to 6" to get a 0 deck??
I really don’t want to buy 6” rods.

well devils advocate here but you cant really do that
it would be easier to offset grind the crank for stroke/deck height issues but this usually requires non stock rods so kinda back to the rod issue sorry
ps when floating stock rods it is much easier (and better in my opinion) to just go steel on steel or basically just hone the pin ends out for clearance of the pins and drill two holes in the bottom (in the middle of the i ) vs just one on top
hth good luck

 

[dr_frankenstein]

why worry at all?

it honestly isnt going to make a alot of difference if you .040 in the hole other than some loss in compression.

using a RJC head gasket, will help in retaining some compression.

what you will loose in compression you can make up for in boost. as quench is of no real concern with turbo dish pistons.

if your that concerned with your final compression, mill .010 of of the deck and heads.

the most impact you might see by 0 decking the motor will be a slight increase of bottom end torque. in my opinion... not worth the money.

A.j.

 

[bison]

Pistons/rods/gaskets for '85 block???

I have been searching this site for over a week now and stumbled across some really good stuff.

This has not really been addressed though. I have a 140 '85 block and need to order .030 pistons. I'm leaning towards diamonds with a 1.850 DH. My block has been cut and my shop will check DH but my guess is around 9.550.

Just order the correct compression height pistons. The block wont matter. Check the pushrod lengths

 

[Turbo-Archie]

Thanks guys!

I guess I was over thinking it.

I wanted to use shelf pistons so I could move them to a 109 block down the road if needed.

Is my math right at least?



..

 

[dr_frankenstein]

no i wouldnt say over thinking it... as its something that matters.

yes your math looks correct, depending on the actual block deck height.

I would confirm your deck height.... I have found early blocks can vary alot, or arent machined square.

A.j.