what are these pistons? now..Which motor to build

[starkypdx]

I'm trying to identify the pistons in the brown hornet. Everything in there mic's out as stock untouched but the pistons don't look right. I don't thing they are stock.

photo is here:
http://www.broncofix.com/viewtopic.php?p=1078486&sid=82a3dbe6372e1b10f5e01817cbeac746#1078486

Help.

 

[bmc69]

Nope, not stock for sure. Those are aftermarket high-compression (very) popups..but I do not recognize whose they are right off the bat.

 

[av bronco]

mabey old trw's but its way over 11 to 1

 

[Broncobowsher]

Any markings on the bottom of the pistons (oil pan view)?

 

[DonsBolt]

My vote is for Keith Black Hypereutectic, but thats just a guess

 

[bax]

Wow. check out the deck height compared to the top of the piston. Is that piston installed? Or is it just sitting in the bore unattached to the crank. The outside edges are up out of the deck at least an 1/8th inch. What heads did you have in this?

 

[starkypdx]

okay more details... I have the crank out of the block and had pushed the piston all the way up so you could see how high the ridge is on those pistons.
There is no name anywhere to be found. The only casting number on the skirt is 1706 R. Nothing else anywhere. The connecting rods are all fomoco.
The heads were 62.2CC 69 heads.

 

[Broncobowsher]

I have looked through a bunch of stuff. Can't find anything.

 

[starkypdx]

The long and short of it:
We tore into the engine trouble shooting work done by the PO. The heads are junk. Cam is flat, lifters are all dished and junk.
Pulled the crank. The crank and cyls all mic out within stock range. The crank journals are all scarred as are the bearings; though the bearings appear fairly new. Perhaps put together in a dirty environment. probably needs to be turned. The pistons look to be in good condition but we have no idea what they are and need some numerical values so we can figure compression if we decide to rebuilt with this.
Here's another question: I also have a never rebuilt 302 out of my 77 that is at my disposal. Would there be any benefit to using my 77 block/crank pistons/connecting rods/ heads vs using the 69 block/ the mystery pistons/conrods and the 77 heads?

 

[wildbill]

The ones in my 68 look like that there 12:1 trw's and work best with the green gas that smells funny. If you run them on the street you will need good gas. The last one I had on the street was a 11:5 to 1 in a 351C with prem. gas and a edelbrock water injector and it worked good luck with yours. Bill %) ;D

 

[starkypdx]

I've pulled all the pistons out and the numbers on the inside of the skirts are:
1706R
1706L 335L

I checked the flatlander racing site and couldn't find a TRW w/ that number.

 

[Broncoholic1]

Pick up a set of 69 - 70 351w = WF heads and you will have 11.5-1 Nice hyd. cam 478-500 range range rv cam and roller rockers 375-400 HP stump puller Oh yes at least 650 double pumper on top with a dual plane Edelbrock Performer manifold. Turn the crank 10-10 and crosshatch 60 degree and you have it Good to go They look Forged that is why they are still there. Look like PAW.

 

[Amac70]

I couldn't find a good picture but they look very similar to trw 2249n piston. Only pic i could find crappy ebay pic, but icould be wrong, very wrong. but then again this is the internet so its not likely you'll find me if i give you wrong information.