Pontiac GTO Forum banner

1 - 5 of 5 Posts

·
64-67 Expert
Joined
·
8,561 Posts
Discussion Starter #1
Helping a friend build a '66 "big car" 389 that will go into his '65 GTO with a 4 speed and a 3.23 rear gear. All the machine work was done previously, and it was never assembled. I checked out the block, crank, rods, etc. and they all checked out fine. Thing is, he had cheapy flat top pistons pressed on to the stock resized/reconditioned rods. He is going to ditch the pistons and run some Ross custom pistons with a dish to lower his compression a bit. He is also going with a Comp Cams 268H cam. He insists on running his "junk" 092 heads (which are redone and check out). The car will be street driven only, with no track use. The BIG QUESTION: What connecting rods to use? The originals, or, as cheap as they are now, some aftermarkets?? He has to get the pistons pressed off, pressed on again anyway, so what do you think? Floating or pressed pins? Thanks..............
Jeff
 

·
Former Moderator
Joined
·
2,895 Posts
stk should be fine, he won't be reving past 4500-5000 prolly anyway. As long as they check out they'll be adequite with pressed pins. Forged pistons are overkill really too, but that's his choice $$. :cheers
 

·
Registered
Joined
·
173 Posts
At this level, pressed pins are fine. The Speed Pro forging is a good one, with plenty of "meat" in the head to put the appropriate "dish". No need for high-dollar "customs".

268H is an old Magnum grind. A much better choice would be XE262H. For the lower compression, we've found no cams to perform as well. Stock valve train parts work fine. Idle is similar to 068 (factory TriPower grind).

RPM rods would be a good "investment". They're reasonably priced and MUCH stronger than the cast rods.

Jim
 
1 - 5 of 5 Posts
Top