iron block main clearance
01-12-2005, 09:03 AM
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iron block main clearance I know it has been answered before but what is the best clearance for a 408 strocker by lunati with a procharger at 14-16 psi , Lunati told me that the perfect clearance would be .0038 on the main and others people are telling me that 0.0025 should be enough. 
01-13-2005, 11:36 PM
#2
Iron block main bearing clearance I'd go with .0025" - .0027" on the mains with the iron block - slightly tighter if this is a street only motor. You will have no oil pressure if you put the engine together with .0038" on the mains. Check the rod bearing clearance too. Make sure that isn't excessive as well. Around .002" to .0025 with good quality steel rods. Run on the low side for street.
Lunati grinds their cranks to minimum published journal sizes. You will most likely need .001" under bearings or a std. and .001" under bearing combination to come up with correct clearances for your application.
Steve
Lunati grinds their cranks to minimum published journal sizes. You will most likely need .001" under bearings or a std. and .001" under bearing combination to come up with correct clearances for your application.
Steve
Originally Posted by Francois Julien
I know it has been answered before but what is the best clearance for a 408 strocker by lunati with a procharger at 14-16 psi , Lunati told me that the perfect clearance would be .0038 on the main and others people are telling me that 0.0025 should be enough.
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Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
01-13-2005, 11:50 PM
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On my 370 my mains are at .0021-.0023 and the rods are the same. My car is my DD so i want good oil presure and i want it to last a lot longer. The looser the clearances the more power it will make but the motor will not last as long. .0038 would be a perfect clearance if this was a pure race car.
Just for ***** and giggles what are your ring gaps. I did mine at 20 on the top and 24 on the bottom.
Just for ***** and giggles what are your ring gaps. I did mine at 20 on the top and 24 on the bottom.
01-15-2005, 10:01 AM
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Originally Posted by Steve - Race Eng
I'd go with .0025" - .0027" on the mains with the iron block - slightly tighter if this is a street only motor. You will have no oil pressure if you put the engine together with .0038" on the mains. Check the rod bearing clearance too. Make sure that isn't excessive as well. Around .002" to .0025 with good quality steel rods. Run on the low side for street.
Lunati grinds their cranks to minimum published journal sizes. You will most likely need .001" under bearings or a std. and .001" under bearing combination to come up with correct clearances for your application.
Steve
Lunati grinds their cranks to minimum published journal sizes. You will most likely need .001" under bearings or a std. and .001" under bearing combination to come up with correct clearances for your application.
Steve
Francois.
