KustomIroc

Hi Guys

I found 2 donor blocks for my 5.7 TPI 86 Iroc-Z.

Can you answer some questions for me?

Which set of heads are better?

Is the block a 4 bolt main?

Is it a roller motor?

Which has the better cam?

How/where can I look up casting number's myself?

89 Chev 4X4 88 Chev Halfton
Heads 14102193 14102183
Block 10054727 10054727

Thanks,
Jamie

In search of more power!

AJ_92RS

You can't tell if either one of those blocks are roller cam blocks unless you pull the intake manifold and look. The only other way to tell would be to pull out a pushrod and measure it.

If the pushrod is 7.195" long then it's a roller cam.

If it's 7.794" long, then it's a flat tappet cam and you still have to pull off the intake manifold to check if it's set up for a roller cam.

Either way, they're both 1 pc. rear main seal. You could just get the lifters that are made to drop in blocks that don't have the retainers.

And the only way to tell if they're 2 or 4 bolt mains is to pull the oil pan and look. No casting number was ever 2 or 4 bolt specific.

The 14102193 heads are junk. They're the 'swirl port' design and don't flow worth a crap over 4000 RPMs.

The other casting number you gave doesn't exist. More than likely the "8" looks like an 8, but is really a 9. So they're the same junk heads.

You can check all the numbers yourself at www.mortec.com
It's a cool website

KustomIroc

much appreciated.