Chevy Pistons in 2F (1 Viewer)

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Im trying to run down the best price on a set of 2F flat top pistons. I need to go 40 over due to one cylinder having some marks.
Anyone know where I can get a set of these for the lowest price?

The machine shop I spoke with said the GM 283cid piston is a direct plug in when you have to go more then 20 over on the 2F. I need to get a confirmation on this before I spend any money on chevy pistons.
 
damn .40 over is a loooong way to go in order to just clean up a cylinder wall...
 
damn .40 over is a loooong way to go in order to just clean up a cylinder wall...

My bad.... one of them needs to go 30 over..... i think he said I could go 40 over and use the 283cid chevy pistons. A full set was about 100 bucks with rings.

I will ask him again tomorrow.
 
I have sealed power pistons in my 2F (part #12139P). I don't remember them being very expensive.

Whatever pistons you use your machine shop will match the bore to the pistons/rings, so I wouldn't be too worried about what is used. You might want to make sure they have one of the connecting rods to make sure everything goes together. If the price you mentioned is correct it sounds more then reasonable.

BTW even if you go .40 over you still have one more bore available at .60.
 
I have sealed power pistons in my 2F (part #12139P). I don't remember them being very expensive.

Whatever pistons you use your machine shop will match the bore to the pistons/rings, so I wouldn't be too worried about what is used. You might want to make sure they have one of the connecting rods to make sure everything goes together. If the price you mentioned is correct it sounds more then reasonable.

BTW even if you go .40 over you still have one more bore available at .60.

It kinda bums be out because the engine had such good compression. I wrote down what was said prior to the larger bore... 5 of the cylinders where good enough to go with 10 over but he recommends 20 over. The 6th cylinder wall towards the top had more wear and thats when he recommended going with 30 over across them all. I will have to ask about the 40 over... that might have been so he could use chevy 283cid pistons as he said they were the same specs as the 2F with the larger bore.
 
It kinda bums be out because the engine had such good compression. I wrote down what was said prior to the larger bore... 5 of the cylinders where good enough to go with 10 over but he recommends 20 over. The 6th cylinder wall towards the top had more wear and thats when he recommended going with 30 over across them all. I will have to ask about the 40 over... that might have been so he could use chevy 283cid pistons as he said they were the same specs as the 2F with the larger bore.

Do the 283 pistons have a semi floating pins or are they full floating?
 
This could work, just have to overcome a couple little issues...

SBC pins are .928, LC and BBC are .990.

2F compression height is 1.87, 283 comp ht. is 1.80. CR would go from 8.0 to 7.0

2F bore is 3.7", 283 bore 3.875". Need to verify wall thickness after boring .175" out of the cylinders.
FWIW, 305 bore is 3.74", well withing safe boring limit.
 
This could work, just have to overcome a couple little issues...

SBC pins are .928, LC and BBC are .990.

2F compression height is 1.87, 283 comp ht. is 1.80. CR would go from 8.0 to 7.0

2F bore is 3.7", 283 bore 3.875". Need to verify wall thickness after boring .175" out of the cylinders.
FWIW, 305 bore is 3.74", well withing safe boring limit.

Possible pin location issues Jim?

It sure would be nice if I could just pick up a set of hypereutectic pistons and call it good..
 
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2F compression height is 1.87, 283 comp ht. is 1.80. CR would go from 8.0 to 7.0

2F bore is 3.7", 283 bore 3.875". Need to verify wall thickness after boring .175" out of the cylinders.
FWIW, 305 bore is 3.74", well withing safe boring limit.

Since he'll have the head off couldn't he just deck/mill the head and gain a little of the compression back or would he be dealing with valve clearance issues?

What is the max over-bore on a 2F?
 
Like FJ40Jim say's a Chev 305 will go that's what I'm running but pin hight and a few other things need to be addressed if your on a budget better of sticking with stock.

JEPistons.com | SMALL BLOCK CHEVY - 305 SMALL BLOCK 23º FLAT TOP

You can bore a 2F out safley to the 170770 or 170771 part no.

Matt

PS No need to use custom JE's though price is a little restrictive :eek: I also switched to Jag 4.2 straight 6 con rods with ARP rod bolts to suit.

Matt2FETI011.jpg
 
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Thanks for all the info.... very helpful. Now I just have to figure out which pistons sizes to use. I was looking at these last night but in another size. These are the 305cids

305 pistons - JEGS High Performance


I spoke with the machinist today but forgot to being up the what bore he suggested. Ofcourse I want to take off as little as we can and also make it affordable. Im on a budget right now.
 
2F compression height is 1.87, 283 comp ht. is 1.80.
Possible pin location issues Jim?
It sure would be nice if I could just pick up a set of hypereutectic pistons and call it good..
Pin location = compression height = Distance from pin CL to top of piston.
In this case the piston would be shy of the block deck by .070", which would require milling the .070 off the top of the block. Do-able, but it is a lot to take off.
 
Pin location = compression height = Distance from pin CL to top of piston.
In this case the piston would be shy of the block deck by .070", which would require milling the .070 off the top of the block. Do-able, but it is a lot to take off.

Is there anyway to get a higher compression chevy piston to make up for the loss of compression?
 
Is there anyway to get a higher compression chevy piston to make up for the loss of compression?
Sure, order a set of custom hi-deck pistons from JE or Ross or Wiseco...

Or just bore it 1.5mm and install a set of OE Toyota pistons.
:cheers:
 
Pin location = compression height = Distance from pin CL to top of piston.
In this case the piston would be shy of the block deck by .070", which would require milling the .070 off the top of the block. Do-able, but it is a lot to take off.

Would quench become a concern with that much milling? What about decking the block instead of the heads?
 
FJ40Jim said:
Pin location = compression height = Distance from pin CL to top of piston.
In this case the piston would be shy of the block deck by .070", which would require milling the .070 off the top of the block.
Lance Lucas said:
Would quench become a concern with that much milling? What about decking the block instead of the heads?
Milling off the top of the block = decking off the top of the block.

If the piston was short of the deck by .070, there would be no useful quench.
 
Milling off the top of the block = decking off the top of the block.

If the piston was short of the deck by .070, there would be no useful quench.

Sorry, it was very late and I read your post to say deck the heads :)

How thick is the OEM HG? Could you gain some C/R back with a custom-ordered thin HG?
 

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