Sealed Power Pin Bushings 1834V

Would these be the ones I'd need? (0.913" inner diameter).
Why do they not list the outer diameter? How do I know if they'll fit in the current wrist pin hole?

 

Curious about a couple of things:
1. Has the machinist measured the block? Is it at the original 10.00"? If not, your calculations could be off.

2. You mentioned 74cc for the c.chamber volume. Is that an efi head? If not, I thought the pre efi head (300) was 76 or 78cc, can't remember which, ha ha. I imagine, if it's an older head, it has been 'cleaned up' a few times with .010 cuts each time?

3. I would let the machinist decide on/order the bushings if you go that route.

4. I love that sealed power piston in the link with the 19cc dish. According to my calculations, you'll end up at 8.66:1 with the specs you listed. But ... a .020 shave of the block will render, drum roll please, a 8.97:1 cr.

5. How do the bushings hold up?

 

He measured them. When I told him that it was a 10" deck with 76cc chambers (which is what I remembered too), he said, "would you rather me measure yours exactly? Or would you rather go off of what some book says?"
I appreciated that.

The 74.4cc head chambers was with him putting valves in the head and measuring the ccs exactly.

I agree on letting him pick bushings.

And yes, I think the 19cc dish piston would be great. And put me right where I want to be. It'd also allow me to leave a 'little' bit of material on the block and head, in case I ever needed to do anything again in the future. (Hope that's a long way off).

Out of curiosity, what's the compression on your engines?

 

Check these out!

Sealed Power H519P30, Speed-Pro Cast Pistons | Sealed Power

1.767 height.
0.975 pin
22cc

I had to cross reference the information on them from a few sites since none of them had all the details.

Rockauto

More Information for SEALED POWER H519P

SEALED POWER H519P Hypereutectic

Cast Piston; Hypereutectic;
Effective Dome Volume; 22CC;
1.767 CD .300 DEEP;
8.5:1 CR;
Recessed Head D Shape. 9751" PIN DIA;
1 Ring, 3/16 groove; 2 Rings, 5/64 groove

Jegs
Sealed Power H519P30, Speed-Pro Cast Pistons | Sealed Power

Cast Piston
Ford 300
Bore: 4"
Dish Volume -22.0cc
Ring Groves: 5/64", 5/64", 3/16"
.030"
1/pkg

Summit
Speed-Pro Hypereutectic Pistons H519P - Free Shipping on Orders Over $99 at Summit Racing



Those would make it so I don't have to bush the connecting rods, and with the head shaved to 70cc and a 0 deck, I'd have a 9.000 compression ratio.

 

That would mean taking about .030 off the block and a lot off the head to lose 6cc? That's a lot off the head. That seems to be going backwards to me. Of course it's up to you, but I like the other piston with the bushing, and taking only .020 off the block, and zero off the head with 74cc c.chambers, to get 8.97:1 c.r.

Have you seen that piston with the off set round dish of iirc, about 13cc? I love it, but can't find it @ .030 over or hyper.
Silv-O-Lite Cast Pistons 1170-030 - Free Shipping on Orders Over $99 at Summit Racing

*I guess it's been a while since I looked. I redid the math and they have a dish volume of 19.664cc, not the 13cc as I mentioned. Oh well ...

 

He was the one who suggested shaving the head to 70cc and zero decking the block. However, he also said he doesn't like zero decking as that doesn't leave any material for later if issues arise, but suggested it if I wanted to get compression as high as I could with stock pistons.

I still have no idea how expensive bushing the rods is. If it's not that expensive, it's a moot point, since I'd just bush the rods, and get the 19cc 351w pistons. But if it's pricey, the 22cc pistons are a good option since it would fall into the original plan of 70cc head, 0 deck block, but would get the compression up to 9.

As for the Keith Black pistons, how did you find that they're 13cc? I don't see that printed anywhere.

 

Speed Pro sells a set of 351w flat top pistons with four valve reliefs that give up 12cc and are a lot lighter than 300 pistons.

Speed-Pro Hypereutectic Pistons H336CP30 - Free Shipping on Orders Over $99 at Summit Racing

 

Baron, how are you comparing the weight of the pistons? Or is that something you know from previous experience? (I don't see weights listed.)

 

Yeah, I built a 351 with those pistons and the 300 pistons were definitely heavier. I've played with a few SBFs and was surprised when I picked up a 300 piston. I'd wager the size of the pin has something to do with it.

 

I can't wait to hear what you find out about the cost of having the bushings installed.

What is the longevity of the bushings? Pro's/con's?

I'm considering using that Speed Pro piston with the oval dish. It would require shaving my block a total of .030 (.010 more than it presently is), but would give the c.r. and quench I'm seeking: 8.97:1, with a quench of .043.

 

I'm going to stop by and ask him about them this week.

However, the engine build has slowed a little bit due to getting hit by taxes like a freight train. No idea why, or what caused it, but let's just say we owe about what the engine build is going to cost... Ugh.

SO! Hopefully around mid-April we can get this back on track. I'll post updates when they come.

 

This is for all of you guys. Whatever pistons you settle on, you might think about having the machine shop order them. Yes, that costs a little more because the shop can't get most such parts any cheaper than you and I can get them nowdays from the big mail-order outfits like Summit and Jegs, and the shop will mark them up. The mark-up on parts used to be an essential part of the economics of operating a machine shop. Today an auto machine shop is a poor business to be in, which is why these places are closing down one by one, and will not be replaced.

If you have found a really good shop, show them you understand, pay a little extra for them to order the parts to let them make a little more money, and you will be a special customer in their eyes. Another big advantage of this is that the parts are now their responsibility, and not YOURS. Re-read my link on the previous page, about the big issue of bad parts today, coming even from formerly trustworthy sources.

If you are going to provide pistons or any other parts, YOU are responsible for resolving any problems with them. How good are you with precision measuring equipment? Mike-ing the skirt diameter of pistons is only the beginning of it. And even if you are good at this, can you depend on Chinese metallurgy? What's REALLY in those supposedly "high-silicon" pistons or "ductile iron" rings?? Wouldn't you really rather pay a little more to have the shop deal with these issues? Seems to me that is money well-spent. Your machinist is dealing with a whole lot of headaches that weren't part of this business forty years ago, and he deserves to get paid for this (and otherwise appreciated, because he also has to deal with way too many know-it-alls and jerks).

 

well said Smitty

 

Excellent advice Smitty. I'm all for saving a buck or two by doing things myself but there's a time and a place for it. I'd much rather trust parts he's used to dealing with, knows the issues/what to look for etc. And like you said, he has responsibility. An engine rebuild is nerve wrecking enough, last thing I want to deal with is being completely responsible if a bad part fails.
Most of the research on pistons has been to see what's available.

 

For one thing, if there's a problem with a part that the customer brought into the shop, the shop can't get on the phone with Summit or Jegs or even the maker of the part, no, the shop has to phone the customer. They have to set the half-finished job aside and wait for the customer to go through the hassle of trying to get some resolution, and another part. The shop has to be very careful about assuming legal liabilities that their insurance might not cover.

But when it's a bad part that the shop ordered, all the dealings are with outfits that the shop has dealt with many times over the years, and issues get resolved a lot quicker. It's still a gigantic PITA, but not like having some customer's unfinished job taking up floor space for weeks, for which the shop will not get one extra dime in the end.

I'm serious about this, you would be stunned to learn how little net yearly pay the owner of your local auto machine shop gets to take home. As much as these guys enjoy being machinists, and having all the expertise they have acquired over the decades in the business, most of them would do something else in a heartbeat (and get two or three times the net take-home pay) if they could get any reasonable selling price for the business and the physical assets, which they usually can not. So treat them good. Because when they're gone, we'll be stuck with crate-motors (maybe also coming from out-of-country???). This prospect will be very hard to digest for any traditional hot-rodder, who thinks crate-motors are for pussies and pretenders.

Oh well, probably by that point the nanny-state will have closed down all the wrecking yards (and local racetracks and dragstrips) and taken all the old cars off the roads with buy-back programs, and we'll all be mere passengers in our computer-driven electric cars. I'm glad I grew up seeing what I did 40-60 years ago, and will be gone by the time the brave new world arrives.