Fox Compression Ratio 347 Build

Orangepeels

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Aug 13, 2017
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First post... Woot..

Anyways i'm in the middle of my 347 build, have most of the short block assembled (Have yet to buy cam and heads). I measured the piston to deck height tonight and the pistons are sitting at about .017 below the deck.

Looking for around 10.2:1 - 10.5:1 compression.

Piston valve relief is -11cc., I did not have the deck milled. I was going to get afr 185 58cc heads. But after calculating static compression i would be sitting at about 9.78 ish static compression, this is with using a .040 thick head gasket.

I would prefer not to have brand new heads milled....

Another work around i thought of would be to use:
Trick Flow 11R 190 56cc heads
.032 thick head gasket

This would put me right at 10.2:1

Only problem with this is i'm worried about valve to piston clearance. Was going to get an off the self cam which would be the Compcams XE282HR..



Just in case if its asked, engine is going in my 93 fox coupe (Getting painted), going to be mostly used on the street, hp looking for seems too be a lot a lot of peoples goals which would be around 400rwhp...


http://www.jegs.com/i/Scat/942/1-94165BE/10002/-1
^^^^^ stoker kit i bought and installed^^^^

Just looking for ways that i could achieve the compression i'm looking for. Or hoping the workaround would work :)
 

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A5literMan

At least it is lumpy...
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The 11r's design usually increase ptv clearance fwiw and shouldn't be a problem. Also if you want to maximize the power potential and drivability I highly recommend a custom cam. Very much worth the few extra bucks and you can tailor it to the heads/intake etc etc.
 
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revhead347

Apparently my ex-husband made that mistake.
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I can see from here those pistons are going to clear whatever. They are designed for it. I would go for the 11Rs out of principle, they are a better performing head. I wouldn't take anyone's advice on the internet though, because a can of playdoh is 50 cents at Walmart. I agree about milling a new head. I would always have the block 0 decked before I milled the head. Get the head you choose, bolt it together with an old head gasket, and check your PTV clearance with playdoh. If you have enough clearance, then mill the block a little bit.

Kurt
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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The xe282hr can is a good one....that's the one I have but on a 331. A custom camshaft would be built to your needs but those guys also have a list they use to grind cams off of for certain set ups.

If you give compcams a call or shoot an email they'd find a camshaft to suit your needs....probably off the shelf.
 
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revhead347

Apparently my ex-husband made that mistake.
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The xe282hr can is a good one....that's the one I have but on a 331. A custom camshaft would be built to your needs but those guys also have a list they use to grind cams off of for certain set ups.

If you give compcams a call or shoot an email they'd find a camshaft to suit your needs....probably off the shelf.

Absolutely. Tech support is there to help. If they aren't helpful, then they shouldn't be in business. The custom cam thing has become a fad. I really wanted to have one in my engine, and it's nice and all. However, when Comp ground the cam it was within a few degrees of something they already had on the shelf. I bet if I just threw the off the shelf cam in there, it would have likely made no difference.

Kurt
 
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Orangepeels

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I will most likely be goin with the Trick Flow 11R 190 56cc heads and the thinner head gasket. Then see what compcams thinks about a cam.

I don't really want to take the engine apart and take it to a machine shop for 3rd time. :/

I am getting excited to have this car back together. I have had it since November 2016 and it just sat in my garage until a month and a half ago when i decided to tare it down and get it out to paint.
 

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revhead347

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Understandable. I don't think a few points of compression will make that much difference anyway.

Kurt
 
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