Dynamic compression ratio

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Aug 14, 2006 | 10:42 AM

WarWagon

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Dynamic compression ratio

What would be the maximum DCR for a wedge head with tight squish in a towing situation? I was figuring around 7.5, but I've never had any direction on this.

Aug 18, 2006 | 06:48 PM

rusty70f100

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From: Iowa

I'd say 8.5:1 for regular unleaded.

Sep 7, 2006 | 10:28 PM

Torque1st

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Check out the new DCR calculator on the edyno site from our member danlee:
www.edyno.com

Nov 25, 2006 | 11:49 AM

WarWagon

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Well......it's together and running on 87, no problem.....8.9 mechanical, 7.6 DCR, .036 squish.

Dec 30, 2006 | 09:24 PM

bigsnag

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From: Pryor

8.5 DCR would be WAY high. 8.9 static is fine. Maybe could have squeezed it just a touch more, but why? You wouldn't gain that much and would risk needing to run premium. Sounds like a nice rig, War.

Dec 31, 2006 | 06:20 PM

rusty70f100

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From: Iowa

I was running 8.5DCR in my 390 for quite a while. All it took was getting the timing right.

Jan 26, 2007 | 12:25 AM

roger dowty

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From: western montana

the FE's have incredible quench design from what I've heard.. Wonder why that is as compared to other designs?

Anyway I'm getting ready to run 9.5 static with a 212/218 cam in a 400- aussie-iron-quench heads. I ended up with a 8.3 or so dynamic which will need 95-97 octane compared to conventional wisdom- running propane so I'm ok but I will try it with 92 at some point and see how it does with tmeyer's pistons that are designed for the quench heads- wish the heads were alloy....