ok guys i have looked around for more detailed info on this motor , im looking at what kind of compression it came with or how to calculate the compression , any good info will help alot. ive pulled the motor almost completely apart and found nothing good resalts on everything but the compression also someone told me it wont bolt up to my 727 in my cuda , i wanna say bs , let meknow please

Dont know about compression but think it'd be typical 8-8.5 to 1. I know if it came out of one of the big ones, it has different timing cover/water pump housing. Ran to big holes in the head. Shortblock will bolt to a regular 727. Used a few of them.

Posted compression ratios for these vary between about 7.8 and 8.0. (very low) I had a 73 motorhome 440--you probably have "213" heads on it?

Should bolt right up to your 727--provided thats a BB 727 belhousing.

well the piston is 4.182 and at top dead center the piston hight is . 412 center and .215 out side its a dish piston

well if its a really low compression motor looks like it mite be a good turbo motor or nos motor , the bottom end is already forged steel , yeah it has those ugly [Edited by Moparts - Keep it clean] water pumper heads on it , when i picked the motor up the guy told me it was a 440 , i got for $200 and payed $90 in gas to git there and back , so when i found out it was a 413 i was much happier finding out it has all forged steel internals , i feel like i stole the motor from the guy

The "real-world" compression ratio can be as low as 6.8 to one !! .... the heads are closed chambers BUT they are huge ... around 90 cc's.

It was a DAMN good motor for what it was designed for but it is as far from a HP motor as it can be.

Those UGLY heads ? ... are way WAY ahead of the competition "back-then". And those heads still are better than most truck/industrial/motorhome heads even made these days.

im sure they are ,but now it has 906 heads on it with a edelbrock rpm performer cam , 440 1.6 ratio rockers , fluid dampner , and a tm7 intake with a 850 holley dp ,,,, i wanna git it fired , just wanna know the compression is on it .

What head gaskets? .. bone stock 906's ?

felpro , yes stock 906 heads

The FP comp gaskets?

Blue permatorque head gaskets

What is the thickness ?

.039

Depending on the deck height of the block and pistons and the cc's of the heads(which could be as large as almost 90 cc's) ..... you could have LESS than 7 to one ...

well 906 heads are 88 cc not 90 cc and also i mite put a set of 915 heads on it , i dont know yet , ,,,,,,, less then 7 , sounds alittle wrong to me , well i had my nitrous guy come over and do some hands on ,, and came out to be 8.266 compresson with 906 heads

A real bad assumption has just been floated. 906 heads are NOT 88cc, some are, but they can be found anywhere from 88 (or lower) to 92 or so. Not that 2cc makes much if any difference on a 400 size cylinder.

If you were to get all the longtime engine builders on this board to recall every 906 head they ever cc'd I bet you would hear at least one "94".

A 915 should measure about 84cc.

Your mileage may vary!

R.

well he measured the cc with a plexi glass and water with a cc measureing setup , he also flowes heads , out , when i measured everything i was way off , becasue i use a strate edge and i measured from the top and not the bottom so i was waaaayyyyy off ,also the motor doesnt have stock pistons in it , it was rebuilt