piston sources and engine clearances

[doug64cutty]

Hi , I'm new to these motors. I'm planning on buying a cold air complete 86 motor (minus pistons) from Shawn Miller.

My first question is : Are there any quality off the shelf forged .020 over pistons for the 3.8 turbo or must I go custom for that size? Would just going to .030 be easier? The reason behind the .020 size is the block is already at .020 it just needs a TQ plate hone.

My next one is reguarding the finish on the cyl walls and rings. I am used to 600 grit platau hone and moly rings, std tension, std size ring package. this has worked great for me on NA oldsmobile motors with 3-6% leak down avg.

Next is, will I need a girdle to go low 11's in a 3600lb car?

The last one (for now) is where on the net do I find the specs for internal engine clearances. I'm looking for..piston to wall, ring gap, oil clearances, torque specs and the like.

I'm putting this motor in a 1964 olds cutlass HT (3600 lbs) with a 200r4 and so-to-be 3.55's (replacing 3.90's)

It's going in stock (as far as performance) minus emissions equipment. Then as I learn about tuning these motors I'm looking for 11's on race gas and 10.5X28" slicks and 20mpg on premium pump gas an 245/60r15 Kelly-Springfield Chargers.

I'd like to build the shortblock stout enough to go into the low 11's without need for removal. So that is the reason behind the forged pistons and girdle questions.

I'm new to these motors, turbocharging and FI tuning. But I learn quick and have thick skin, so please let loose and straighten me out as needed.

Thanks, in advance for your time and help.

 

[doug64cutty]

ttt

 

[19gn87]

Doug?

Sent you an e-mail.

Mickey

 

[doug64cutty]

Thanks Mickey that info will help a ton.

I'm just left deciding on whether to go with Hyperutectic or Forged. I have never tried Hypers, but hear good thing about them IE lightweight, and good as forged if you stay outta detonation.

Who makes a good set .020 over?

The JE's forgings for $680 strike me as spendy. A few folks I know are getting sets of 8 custom CP's for $100 less.

thanks for any help.

 

[jastrckl]

if that 200 r4 isn't BRF, I'd work on beefing it up a little in order to run 11s in a 3600 pound car. new gov and valve body at a min I'd imagine but I'm no tranny guru. Overfilling the thing by a quart helps from all I've heard. Another trick I've learned is mill the pan a little bit to fit a 400 filter. there are like little bumps you have to chop down and then you're set.

 

[Russ Merritt]

680? I paid 502$ for my .020 JEs, part # 131556. My machine shop got em. I'd go forged if I were you.