plaf713

iTrader: (8)

how much will my compression drop using trick flow heads, the heads have 62 cc. do you think i will drop under a 10;1 compression?

siniSSter

iTrader: (2)

It will drop your compression, please post up which pistons you used, head gaskets, and if you zero decked the block...

plaf713

iTrader: (8)

i dont have anything yet, jsut asking, i know it drops compression but does anyone have an average drop, i know its broad

siniSSter

iTrader: (2)

Many factors come into play, but anywhere from .5 to a full point loss. You could shave the heads, use a thinner gasket to recover some of the lost compression though.

plaf713

iTrader: (8)

i have heard that a full point in lost compression only equals out to about 10 hp, everyone seems to think you MUSt have high compression. im not really sure. i think if i have a 10:1 compression ratio i will be fine.

siniSSter

iTrader: (2)

I've heard otherwise. A full point is somewhere around a 5% to 10% loss. High compression will work wonderful, for a N/A application. Low compression is usually for boost applications, where forced air will raise compression, thus needing low compression. Tell me your future, and why you chose TF heads.

plaf713

iTrader: (8)

well i chose the heads because i kid was selling them for 1000 dollars with a tiny bit of head work on them, and i needed some heads. i have a 383 so i figure why not. i dont know all the specs on my motor, there after market pistons but designed like the original hyperautic (they have 4 small dishes). i guess i look at it as 10:1 compression is low compared to most people with stroker, excpet sc's but 10:1 is a good number for a regular motor. i was going to put a thinner gasket on it though. i was told that the impala gaskets are thinner than chevy gaskets.

396D1SS

iTrader: (21)

a hot cam is to small for that motor

siniSSter

iTrader: (2)

Pistons are real important to determine what compression your running. Your options are not over though, you can still hit about an 11.1 working on the head's cc. You can even use a thinner gasket than the Impala (0.29). Victor Reinz (0.26 compressed thickness)Good luck on your buildup.

plaf713

iTrader: (8)

thanks man i appreciate your help, sorry i couldnt get all the info that you needed. i know the hotcam is to small, but i really dont want to go through and put another cam in, i do not feel comfortable doing a cam, nor do i have the money. it sucks. what do you think getting heads milled will cost?

siniSSter

iTrader: (2)

Not very much, plus it ensures a good seal. Once you do decide to change the cam, make sure you get all the specs on the motor, then call to get a custom grind for you application. Your car will fly......trust me

LT1MAN

iTrader: (6)

the specs on his motor are LT1 383ci, line honed, bored +.030, clearcnced, internal balanced 3.75 stroke eagle "esp" crankshaft, premium plasma moly file fit ring set, eagle cast crank, eagle "sir" forged I-beam connecting rods, clevite 77 rod and main bearings, comp cams roller lifters, comp cams hardened push rods, cat aluminum full roller rockers, arp head studs, cloyes double roller.
his cam specs are 219/228@.050 4.92/4.92 with 1.5's or .525/.525 with 1.6's. (close to hot cam).

P you should really just keep the heads you have, they flow well. what you need is more cam. dont buy the heads, if hes selling them for dirt cheap theres something fishy anyway. just get a bigger cam, didn't you send it back anyway

plaf713

iTrader: (8)

the heads are ****, i took them to a shop and they told me that the heads had a tiny tiny port job on them, i just took the heads off, im sending him his heads and getting my money back.i just dont trust the heads he gave me ya know? i dont know what he did to them nor has he proven otherwise that they were actualy ported like he claims. i dunno i just want to move on ya know. i def want a bigger cam, im just not comfortable doing the work.

LT1MAN

iTrader: (6)

yea i agree with you on not wanting to do the work. he matches his heads to the cam thats going in the motor, you chose a small cam, so he did minimal headwork. he has someone grind the cams for him. my heads looked pretty damn straight, but ive yet to get it on the dyno or on the road. he gave me flow numbers on mine, after about 40 emails. i havent tested them myself.

Karl Ellwein

If you have a 383 right now with GM LT1 casting cylinder heads and a flat top piston you already have high compression (around 12.6 to one)

The 64cc Trick Flows could be a very nice head and take you to 11.1 : 1

(I guessed on a .039" FelPro head gasket).

Karl