Ok I just purchased a 68 440 block came with a ton of parts

Balanced forged crank
Speed pro l2355f forged pistons .30
Connecting rods
Arp everything adjustable rockers
Oil pump
Mildon pan
Windage tray
Bearings
Mp 312/590
And mildon megaflow competition valves

My question is I looked at the pistons and they seem to be 9.37-1. He told me that the valves were for 906 heads are the head specific? I was told that the engine should have 700 hp with the right heads. I doubt that but I know he was planning on using a charger which I am not. So is the compression going to be to low? And what heads would be recommended
Thanks Joe

Also I don't need or want a 8 second car. I would like to run pump gas. The pistons are for 88cc heads if I run a smaller chamber that should raise the compression if need be?
Thanks Joe

thats way too much cam for 9.4 compression. any closed chamber head will give more compression. stock type valves are short and should be used in a stock head.

Assuming the compression is correct for those pistons on an 88cc head, then bumping the cc's down to 84 would give you a half point of compression or so?

This would probably get you into the high 9's with 84cc heads and the thinnest head gasket you can find which is fine for pump gas.

I would recommend you buy a set of 84cc Eddy RPM heads which will give you the desired compression rise. They will also be more tolerant of higher compression on pump gas than the traditional iron heads.

As far as 700hp out of that motor...that is pretty optimistic for this build naturally-aspirated. I am guessing he meant to use a blower which would explain the lower compression. I would guess you would be anywhere from 400-425 hp with the build you described and a good set of Eddy 84cc's and good intake/carb/headers/etc.

First, valves that fit 906 heads will fit any production 440 head but they will not fit in any head that could possibly make even close to 700 HP normally aspirated.

Second, that cam will definately like more compression. I would think that 11:1 would be the practical minimum. More would be better. Your not going to get there with these pistons. Also the valve notches will be too small for this cam and need to be flycut deeper. This will reduce the compression even more.

Bottom line is that 700HP is not going to happen with those parts and neither is 600HP. More like 500HP. Don't worry about it being an 8 second car. This is a high 10 - low 11 build at best.

You are going to need a good set of aluminum heads (CNC ebrocks or better) different pistons and possibly a better cam to approach 700HP. At that point the stock block and stock rods start to become very questionable.

If this is for a pumpgas street cruiser I think I would sell the cam and the valves. Buy a set of 84cc ebrocks and a smaller cam. Zero deck the block, and cut a little off the heads to bump up the compression some. You will make well over 500HP and You will be much happier with it.

I should rephrase what I saisd I know 700hp is not going to happen nor do I want it. I am shooting for the 500 mark. That being said are there stock casting heads that are less than 88 cc that I can use the valves that I already have. I am going to deck the lid to get some more compression out of it. The valves I have are mildon 45275-8 and 45266-8 or should I just sell the valves and buy aluminum heads. What cam should I switch to?
Thanks Joe

by the time you find a set of 906's or whatever stock head you pick, get it checked, cut them out to an acceptable level of breathing,put in unleaded seats (906's) yadda, yadda, yadda you could find a modern set of heads with all this done. save yourself the aggrevation and don't ask me how i know, ok?

Getting to 500hp is going to be difficult with the stock heads. I agee that you would be better to buy Eddy's or another modern aluminum head and start there.

To attain 500 hp you will need to probably still put some port work into those Eddy's to get the flow numbers up. An altenative might be to bore and stroke the 440 to a 470, 500, or higher. That will give you a better compression and more inches to get you there!