Originally Posted by Rich Biebel (Post 593547)

I’ve never seen or used those pin locks.

My own engine in my dragster has Diamond pistons and spiral locks the std. used for many years. Single or double and I’ve never had one break or come out.

It was s.o.p. to verify the pins had some clearance or movement between the locks. Every piston I assemble, I check to be sure the pin can rotate freely in the piston without binding on the locks.

Obviously something way wrong with the lock, piston, pin arrangement.

That was a real bad mess and should not have happened given they were all good name brand parts.

Years ago we used a snap ring type pin lock. Spiral locks became the normal lock usually used. The locks tend to dig into the groove and raise up a burr but unless they were not installed right, rarely failed.

Very ugly mess. I’ve seen plenty of blown up engines. It’s never pretty and always expensive.

Sorry to see it ....

Originally Posted by MikeMoller (Post 593671)

Todd,
Make sure you check that head for cracks. If they have been milled quite a bit to get the right cc's they can crack easily from a piston or valve hit.

Originally Posted by Rod Greene (Post 593679)

DEJA VU all over again Reading your posts I have learned way more than I ever wanted to know about a Cheby. Wish we could get blocks for our Mopars in 2 days.

Originally Posted by Greg Reimer 7376 (Post 593784)

Did you notice how much heavier that Dart block is over an OEM GM block? It should stay round for you for a long time.That thing is massively thick! Most of the machining is very close or spot on, the only thing once the block is bored and trial fitted is to check the deck height and correct as necessary. Best wishes for a great engine this time around!

Originally Posted by Greg Reimer 7376 (Post 593827)

What casting number is that head? Do you have any spares? I assume it's 1.94/1.500" valves.

Originally Posted by gmonde (Post 593828)

You guys are troopers,,,almost in the top fuel range

Originally Posted by Glenn Briglio (Post 593897)

Whose connecting rod bolts are you using?

Originally Posted by Nmbr1GMfan (Post 593901)

ARP.

Originally Posted by glenn briglio (Post 593910)

which arp?

Originally Posted by Mark Yacavone (Post 593968)

Question for a few here.
The Molnar rods come with their own bolts..all fitted and sized. Same with Manley and the rest of them. Why would you want to change them on new rods?
I use ARP all the time and a great product, so that's not my point.
Just seems like some will never pass up an opportunity to spend more money, no matter what. LOL

Originally Posted by Glenn Briglio (Post 594008)

8740 bolts not the best.

Originally Posted by Nmbr1GMfan (Post 594028)

I believe even the 8740 bolt would be just fine for a 400ish hp engine.

Originally Posted by Nmbr1GMfan (Post 594028)

Glenn, these Molnar rods come with the ARP-2000 bolts and if the bolts were to be changed the rods could need a re-size. I believe even the 8740 bolt would be just fine for a 400ish hp engine.

Originally Posted by Greg Reimer 7376 (Post 594122)

UPS tracking indicates that your 993 head is out for delivery by the end of today. Those people aren't kidding about the 2nd day delivery!

Originally Posted by Wayne Kerr (Post 594209)

Hello Todd,
I have been following your journey and can't imagine the heartache that you have been through.
I have been involved in professional racing for a really long time, and I would like to share some advise I was taught by one of the best: if you expect different results you have to change something. Please don't use those "fancy" wristpin retainers again. Round wire retainers or double spirolox have worked for ever. And be certain to have .030 or more wristpin end play, the pistons deflect and the wristpins broach the clips out. That lesson was an expensive one, we lost multiple Indy and Cup engines because of that. That piston deflection is one of the reasons you see "box bridge" pistons nowadays.

KC