[Mwieczorek]

So, I have a 1966 421 block with 4 bolt mains. It has been bored to 4.180" (I bought it like this). I did have a friend who is a retired machinist check it with his sonic tester. He laughed and said "you can run it like this, but you can't bore it much more". Fortunately for me the bores are round and straight and there is no ridge. This engine was not together long, previous owner had cast rods in it and spun a rod bearing. It's a shame because he spent some money on block prep. It was line bored, decked, etc... It was running 670 heads with some ancient TRW domed pistons (if anyone knows the specs on a TRW 1765P +060 piston I'm all ears)... Best I can calculate his compression ratio was 12.1:1.

The crank was already cut 0.020" and I can't get 0.030" under bearings, so its out. I do have a 455 crank in my stash. It is stock and would clean up with a 0.010" cut. This is going in a 66 Bonneville with a 3.08:1 limited slip rear end and TH400. It's a heavy car, so I need some low-end torque to get it moving.

Now... I'm not totally broke, so I'm going to spring for a set of "decent" rods. I've been looking at the Summit H beams or the Eagle SIR I beams. Seems like either will do the job with a $100 or so difference in cost. I'm leaning towards the H beams because they use a floating pin...

Pistons... What to do here? Pickings look pretty slim anymore. It's the KB Hypereutectic slugs for around $600, or DSS or Icon forged... That decision partly depends on heads. Are the KB Hypereutectic pistons good to go? I'm not planning on using nitrous or a blower or turbo.

Heads... I have several choices. I have a set of 1968 15 casting 72cc heads that have been ported and fitted with 2.11/1.77 valves. They have, bronze guides, positive seals, springs that will go to beyond 0.500" lift, etc... They're probably the nicest ones to use. I also have a set of ported 6X-4s with stock 2.11/1.66 valves. Those would also work, they have a set of Spott's high lift springs & retainers so they can handle .500" lift easy.

Here is one thought... The 72CC heads with 30cc dished pistons (with the piston 0.010" in the hole and a 0.030" gasket) would leave me around 9.5:1 static CR. That ought to be safe to run on 93 octane... Or the 6X-4s could be made to work with a little effort and run with flat tops and put me around 9.7:1 (assuming 93cc chambers, 7cc valve reliefs, pistons 0.010" in the hole, 0.030" head gasket). Is there any real disadvantage to running the smaller chamber heads with dished pistons?

Whatever I get for pistons and rods, the whole rotating assembly is going to the machine shop. The crank needs to be cut and I'm going to have it balanced properly. I even have a nice early style harmonic balancer to go to the shop with it. That way I can re-use all my stock accessory drive bits.

The bumpstick... What do y'all recommend? I'd love to go with a hydraulic roller, but given that I'm buying pistons/rods/bearings/gaskets/oil pump/etc... I don't see it in the budget. Has anyone had any luck with Paul Spott's cam kits on ebay? He has a 041 clone or a 068 high lift that caught my eye. I would buy the kit with lifters that he recommends to be safe. I will be using an engine run stand so that I can break in the cam before it goes in the car. That way I can check it for leaks and whatnot too.

What is the best route to go with the rear main seal? I know the rope seals aren't what they used to be. I don't mind springing for a BOP seal. I see they sell a 2 piece, a 1 piece, and a rope seal. What do you guys use? IIRC I have to have the crank seal area cleaned up to run a modern lip seal, but left as-is to run a rope seal.

For induction... I have a complete 1966 Tripower setup so its going in the car. Exhaust will be RARE long branch manifolds and exhaust (again, I already have it so its going in the car).

Thoughts?