Engine and Transmission Tech

It might be. You'll know more when you get the pan off. See what identifying marks you can find on the piston once you have it out and we'll try to help identify it and look for a replacement.

Goes without saying, you're excused from the upcoming weekend here. But just to be clear about it. You need to get your ride back together. Whatever we can do to help, we will.

There's some chance I'll have my car off the rack before the weekend. So we'll be swapping that pumpkin in the RM. I'm sure three of us can handle that.

Jim

Plan A is out. It is #7 & most all of the full shirt below the wrist pin is gone all the way around. Bee rockin' itself to pieces for awhile.

So, I need one good 1963 Buick 215 JN block 11:1 piston, standard bore . Almost a flattop. Markings say 1353005 Buick on one side & C, then a circle with a 6 in it & BOHNALITE.





Edited 1 time(s). Last edit at 05/16/2017 11:20AM by MGBV8.

Skirt used to look like this.

Looks pretty good actually. Any ring land in the cylinder? Bearing OK?

Have you gathered up all the pieces? You should do that so you can get the total piston weight.

Flat top? Should be able to measure the pin height. Match the pin height and piston weight, slap it back together and run.

It doesn't look like the Silvolite that Summit is selling, but close. They have a slipper style that should work if the weight and CH is close:
[www.summitracing.com]

I wouldn't worry too much about the compression ratio.

Jim

May have lost a few smaller pieces years ago doing an oil change. Never saw any, though. It is very, very close to being a flat top. I would think a slipper piston would be much lighter. Dale said if this was a slipper, it would have likely grenaded the engine.

I had this idea that Dan Lagrou might have one way back in the corner of his shop somewhere. I am trying to reach Mark.

There must be other vendors that might have one as well. Phil Baker in Washington comes to mind. Also, Moss could possibly have something. Even TA Performance, they used to be Kenne-Bell. All the old vendors. Probably no Vintage OEM though, it seemed the High Compression Buick 215 supply dried up just about completely in the 80's so you really are looking for something in the corner or take-outs. Which could be a possibility. You're at a stock bore size aren't you? (Better check it.) Mine are long gone so no help there.

Seriously though, I wouldn't get all that hung up on CR. First off, the Buick 4bbl engine was 10-1/4:1 so I'm wondering where you got this 11:1 figure from. Then, the Buick factory CR specs tended to be flexible and optimistic, and the only engine in the series that I know of that really could have been 11:1 was the Olds Turbo motor. (Weird, right?) But it had the same chamber volume as the 4bbl Buick heads. Then what if one cylinder is lower compression? It'll still run just fine. Lose a smidge of power maybe but how long do you plan to run that engine?

Now, let's review CR a bit. All Buick heads have the same chamber volume? So they changed CR with the pistons right? All Olds used the same pistons so they changed CR with the heads? I think that's right. Harry used 2bbl Buick pistons to build a 2bbl Olds and got about 6.5 CR out of it. Still ran. Worked as a spare, but idle wasn't great and mileage sucked. With a turbo mounted on it it was tolerable. Even carbed it beat hell out of an 1800.

So a any Olds piston would also work. How about 3.5 Rover? Do a quick calc of chamber volume and you might find one of those is also close enough.

Jim

Mark LaGrou is going to check the back corners of the attic. A local club friend is retired from GM & has sent a request to Detroit friends.

I would prefer a good used piston & reuse the rings/rod bearings as you mentioned & forget any honing.

As for CR, the 10.25:1 you quote is for the 185HP 4bbl in 1961 & 1962. In 1963, they bumped the CR to 11:1 & rated it at 200HP.

[www.carnut.com]

Carl, give us a skirt diameter and where measured, in relation to pin location. I'll look as soon as I can. Good Luck, Art.

I would be very cautious about using flat top Olds pistons, with Buick heads. Valves are in different location !

Carl,

What I still can't believe is that the large piece made it up to the lifter valley! You would think it would have jamed itself in the bottom end. And how did it not wipe out the cam getting up there, or lock up a push rod???

Engine gods were smiling up on you!

Carl, just an idea... I dont know much about the BOPR series of motors. If you can't find a piston, is there a BOPR you could pick up used that'll work with your headers, bell housing and accessories? If so, maybe you could swap out the motor or short block at least. Then simply resell it after the meet. I've don that with expensive tools. Sometimes even made money when reselling.

Tony Gentile just posted an engine for sale - maybe something here?

[www.racingjunk.com]

Carl,

Glad you decided to investigate further. It would have sucked to have that piston let go during the meet. You still have 3 weeks (from today!) to get something in place.

Scott

Hope you're looking at the motor Tony posted:
[www.racingjunk.com]

Sounds about like the motor you bought when you did your conversion originally. Oklahoma, $500.

Jim

The engine I bought 16+ years ago for $600 was already rebuilt. :) I have options (besides R&R and rebuilding an engine in 3 weeks). Too short on time. I drove my dad's original owner '63 B to the MG V8 Meet in Westlake, Ohio in 2000. It may be coming to WV. :)

Dale Spooner said he has seen a piece o' skirt in the lifter valley once before. The cam looks good. I was surprised.



Edited 2 time(s). Last edit at 05/17/2017 11:57AM by MGBV8.

I agree with caution on the Olds flat top piston, Art. I do believe it would work with my "stock" cam. My 11:1 piston only has a .010" dish & is .060" below the deck. The head gasket was a compressed .050". IF the Olds has the same compression height, I'd try it.

My piston measures 3.502 on the wrist pin centerline. There is not much skirt left.

That engine above isn't rebuilt?

Not the way I read it. Also, local pickup only in Oklahoma

" engine was dismantled for rebuild but my project list has changed..."

There's a few sets of used piston and rod sets on Ebay right now.

[forum.britishv8.org]