Gotta know what kind of motor,comp.ratio your looking for,cam specs,intake you plan to use,weight of the car(an idea),converter stall,rear gears,etc.And how much power you want to make.
Edelbrock RPM heads 70cc
I Just Wanted To Know What You Guys Think About These Head.
Edelbrock Aluminum Rpm 70cc Combustion Chambers Flows 170cc 575" Lift
Edelbrock Aluminum Rpm 70cc Combustion Chambers Flows 170cc 575" Lift
1 - 2 of 8 Posts
Mario,sounds like a good torquey combo.Dave mentioned above that a 200cc head might be more in the ballpark.And I tend to agree,except that the info you gave is misleading.
First, a 10.25:1 piston is measured using a 64cc head and a 9.025 deck heigth.Now not knowing what your block is,(besides a .060 over 350) or your deck heigth or the head gasket thickness,I can almost guarentee the compression ratio will be between 9.4 and 9.7.You did state that your combustion chambers are 70cc,right.
Second,the XE274H cam is a split duration with 230 and 236 duration at .050and .490 lift on INT.and EHXT. With 1.6 rockers,lift should be around .512 and duration should pick up 2 or 3 degrees.
Thirdly,the converter you have in my oppinion is too high.A 2200 should be plenty.
Forth,carb is too big.Use this formula;CI X max PRM / 3456 X V.E.(volumetric effeciency)usually 85% but most use 100%. 600 Vac.Sec.should be plenty.If you do decide to use the 750 Double pumper,don't be suprised if it idles very rich.
And last but not least,remember that when you build a motor or a whole car for that matter,that you should try to match EVERYTHING to work togeather. Your transmission sounds like a good choice.And a rear gear around 3.50,will give you plenty of torque to fry the tires while still cruse at a decent RPM.Intake is perfect.
Just trying to help man.
First, a 10.25:1 piston is measured using a 64cc head and a 9.025 deck heigth.Now not knowing what your block is,(besides a .060 over 350) or your deck heigth or the head gasket thickness,I can almost guarentee the compression ratio will be between 9.4 and 9.7.You did state that your combustion chambers are 70cc,right.
Second,the XE274H cam is a split duration with 230 and 236 duration at .050and .490 lift on INT.and EHXT. With 1.6 rockers,lift should be around .512 and duration should pick up 2 or 3 degrees.
Thirdly,the converter you have in my oppinion is too high.A 2200 should be plenty.
Forth,carb is too big.Use this formula;CI X max PRM / 3456 X V.E.(volumetric effeciency)usually 85% but most use 100%. 600 Vac.Sec.should be plenty.If you do decide to use the 750 Double pumper,don't be suprised if it idles very rich.
And last but not least,remember that when you build a motor or a whole car for that matter,that you should try to match EVERYTHING to work togeather. Your transmission sounds like a good choice.And a rear gear around 3.50,will give you plenty of torque to fry the tires while still cruse at a decent RPM.Intake is perfect.
Just trying to help man.
1 - 2 of 8 Posts
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