Compression Height - AMC Pistons

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   You know CompCams didn't suggest any specific C/R.
And re carb. it's a 470 cfm truck avenger not 670.

Now, I'm sure I cannot find thos con.rods of 390 here in Iran, but instead I'll have to order the pistons. But as you mentioned the compression height is 1.570 so, what would that give me? C/r? I'm sorry, but I'm a poor c/r calculator.

Does that do me any good? the EGGE pistons?
Or shall I just shave the block?
Or should I just put the edelbrock heads on and it'll be better?
Because I don't have more than 5,000 miles on the engine it's too much to take everthing off to shave it. 
I'm confused, pls advise me.

Thanks,
Houman

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Cj-360 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/19/2008 Status: Offline Points: 25	Post Options Post Reply Quote Cj-360 Report Post Thanks(0) Quote Reply Posted: Oct/21/2008 at 6:59am
	You know CompCams didn't suggest any specific C/R. And re carb. it's a 470 cfm truck avenger not 670. Now, I'm sure I cannot find thos con.rods of 390 here in Iran, but instead I'll have to order the pistons. But as you mentioned the compression height is 1.570 so, what would that give me? C/r? I'm sorry, but I'm a poor c/r calculator. Does that do me any good? the EGGE pistons? Or shall I just shave the block? Or should I just put the edelbrock heads on and it'll be better? Because I don't have more than 5,000 miles on the engine it's too much to take everthing off to shave it. I'm confused, pls advise me. Thanks, Houman
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PHAT69AMX Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/07/2007 Location: West Virginia Status: Offline Points: 5919	Post Options Post Reply Quote PHAT69AMX Report Post Thanks(0) Quote Reply Posted: Oct/22/2008 at 12:56pm
	Posted a reply in the other thread.
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redrebel Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jan/19/2012 Location: Kenosha wi Status: Offline Points: 208	Post Options Post Reply Quote redrebel Report Post Thanks(0) Quote Reply Posted: Sep/13/2017 at 6:31pm
	Comp. ratio help 70 390 030 over 048 head gaskets 72 401 crank K1 401 rods Wiseco 030 9.5:1 pistons runs great Thanks in advance

redrebel Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jan/19/2012 Location: Kenosha wi Status: Offline Points: 208	Post Options Post Reply Quote redrebel Report Post Thanks(0) Quote Reply Posted: Sep/13/2017 at 6:34pm
	sorry typo 040 head gaskets

WesternRed Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Aug/03/2010 Location: Australia Status: Offline Points: 5799	Post Options Post Reply Quote WesternRed Report Post Thanks(0) Quote Reply Posted: Sep/13/2017 at 7:56pm
	Wiseco also does a forged piston for the 360 with 21cc dish that would bump up compression but will obviously cost more. You can also get a gain by running a thinner Cometic head gasket that can be ordered in any thickness down to 0.027", assuming you don't mill the block for zero deck clearance and still have the pistons down the hole at least 0.010" or so.

redrebel Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jan/19/2012 Location: Kenosha wi Status: Offline Points: 208	Post Options Post Reply Quote redrebel Report Post Thanks(0) Quote Reply Posted: Sep/13/2017 at 8:02pm
	Motor is done and in the car runs good just want to make sure I got a good idea what the compression ratio is thanks

redrebel Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jan/19/2012 Location: Kenosha wi Status: Offline Points: 208	Post Options Post Reply Quote redrebel Report Post Thanks(0) Quote Reply Posted: Sep/13/2017 at 8:14pm
	Motor is done and in the car runs good just want to make sure I got a good idea what the compression ratio is thanks

PHAT69AMX Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/07/2007 Location: West Virginia Status: Offline Points: 5919	Post Options Post Reply Quote PHAT69AMX Report Post Thanks(0) Quote Reply Posted: Sep/13/2017 at 9:37pm
	CR Calc Requires ALL these Values: x.xxx" Block Bore x.xxx" Crank Stroke x.xxx" Block Deck Ht x.xxx" Con Rod Length CtoC x.xxx" Piston Comp Ht x.xxx" Deck Clearance, +=In-Hole xx.xx cc's Piston Dish Volume xx.xx cc's Cyl Head Comb Chamber Volume x.xxx" Head Gasket Thk x.xxx" Head Gasket Dia Note: All values used are Nominal, have manufacturing variations, and should be confirmed from actual parts for actual Values. Note: DYNAMIC EFFECTIVE COMPRESSION RATIO is ....... The 1st & "MAIN" GOAL and "DESIGN FACTOR" or whatever... Somewhere between 8.5 & 9.0 to 1 DYNAMIC CR is the GOAL... 1st Determing "choice" is .... THE CAMSHAFT..... CAM INTAKE VALVE CLOSING ANGLE "DRIVES" EVERYTHING ELSE relative to ALL Other PART SELECTION and MACHINinG WORK Cam Intake Valve Closing Angle determines Dynamic CR that results from the combination of ALL the other parts. Maximum Dynamic Effective Compression Ratio Maximizes HP & Torque.... on PUMP GAS ! Pick a TOP SPEED in MPH, this yields Feet per Minute. Pick the REAR TIRES, this yields TIRE RPM. Pick a REAR GEAR and Trans Final Drive Ratio, this determines DRIVESHAFT RPM.... Pick a Max Engine RPM, this Determines the CAMSHAFT. Now from the CAM, pick all other MOTOR PARTS to get 8.5 to 9.0 to 1 Dynamic Effective Compression Ratio. All nothing more than the opinions of one man. Not worth the paper they're printed on.....
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