High compreeion 3.1 pictures.

[trotterlg]

Well, just one now. Just back from the rebore .020 over with the iron head pistons in it. Just for anyones knowledge, from the top of the deck to the bottom of the shallow piston dish measures .128 on this engine. From the head surface to the edge of the exaust valve measures .127 on my heads, so at TDC and a .050 head gasket there is about .300 valve to piston clearance. Larry PS compreeion=compression

[bszopi]

If those are flat tops, which I am assuming they are, and based off what you listed in the post, and using 3x00 heads, I came up with 10.19 CR, but a quench of 0.178". EEEWWWW!

[trotterlg]

They are a 12 CC dish, when I run the CR program I get about 12 to one. Larry

[bszopi]

Ahh... I was using the .128" as the distance from the top of the piston to the block. Since its a dished piston, and re-reading your post, that distance is actually from inside the dish to the block. How about the distance from the edge of the piston to the block?

[trotterlg]

.020

[GrandAmGTTT]

what connecting rods are you using and are you planning on running it on pump gas or race fuel?

[TechRod]

what connecting rods are you using and are you planning on running it on pump gas or race fuel?

Which also kinda brings up the question of what cam you intend to run.

[trotterlg]

These are the stock 3.1 rods with the iron head pistons on them. I think pump 91 gas will be good if I run it a little rich. I am doing the valve to piston measurements to determine what cam lift and duration I can run in it. The 3/8 adjustable rocker studs are perfect in this head. Larry

[trotterlg]

I got the heads back on, used the iron head fel-pro gaskets. The LS6 springs installed at a heigth of about 1.725 that will make a seat pressure of about 125 pounds I think. With the flat tappet cam and lifters the long pushrod works right in the short hole, so I just need some 6.25 or 6.3 inch pushrods for the other side. I know it isn't fancy, but it is coming together. The tophat type SBC stem seal/valve seat worked perfect. Larry

[geoffinbc]

I hope you did not use SBC valve stem seals for 11/32 stems on a cylinder head with 8mm stems.

[trotterlg]

I hope you did not use SBC valve stem seals for 11/32 stems on a cylinder head with 8mm stems.

No, these are the ones I used:

Hat style, spring base seals can be really pricey.
Alex's Parts has an excellent price on these. ($1.56 each)
Premium Quality Blue Viton!
Our Viton Seals are the finest positive valve seals available
8mm valve stem X .499"-.500" guide
Buy it now for only 24.99 for a set of sixteen seals.

[geoffinbc]

Good deal.

[trotterlg]

I know I am slow, but there are just a lot of little details to work out with this conversion for a Fiero. The latest picture with it mostly together. Now I need (if anyone has them) some early S10 or Camaro pulleys for the front. Larry

[Blacktree]

From the head surface to the edge of the exaust valve measures .127 on my heads, so at TDC and a .050 head gasket there is about .300 valve to piston clearance.

YOUCH!

Even the mildest of camshafts for the iron-head engines yields 0.390" lift at the valve.

[trotterlg]

The valve lift with 1.5 rockers is .426 intake and exaust, the .300 is the clearance to the pistons with the piston up and the exaust valve open. Larry