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sbc 383 help

  
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sbc 383 help

 
Loserlv Loserlv
New User | Posts: 6 | Joined: 08/10
Posted: 07/09/14
02:16 PM

i bought a 383 from a local guy last week for my sons street 1973 c10. he ran it on the street for a couple hundred miles and decided that $8 a gallon fuel wasn't going to work. He built the motor with around 11.5 to 1 compression. my calculations come in at 11.4. my question is can i run this on the street on premium with these heads and if the tune is right. or should i lower the compression.  If the answer is drop the compression, whats the most cost effective way to loose a point of compression. open up the heads combustion chambers. install dished piston(which I'm going to have to re-balance the assembly (looks like the pistons are about 20g difference.) thicker head gasket and ruin the quench. switch to e85. or any other suggestions.

this is what i know is in the engine.

scat 9000 crank 3.75 stroke
5.7 h beam rods
probe fps .060 over forged pistons 1.425 compression height -4cc flat tops
he says the block was at 0 deck height
patriot 64cc 210 intake heads
Lunati cam (summit # lun 10120704lk) 110 lobe sep. 504 intake lift 525 exhaust lift. duration at 050 233int 241 ex
1.52 aluminum rockers
arp bolts
performer rpm intake
850 Holley QFT vac sec

how do i make a good reliable street motor out of this combo. I also have a another block that I'm guessing is 30 over.  

allend43 allend43
New User | Posts: 4 | Joined: 07/14
Posted: 07/17/14
09:10 AM

You can do it with another camshaft a couple of ways. You can replace your present camshaft with one of the same specs but with a wide lobe center like 113-114, or go to a bigger at .050 camshaft. Either way it will bring down the cranking compression and lower speed cylinder pressures, allowing you to run pump gas. Have you done a compression test on your motor? If its about 190lbs or less it may run on pump gas. Have you tried running it on pump gas?  

allend43 allend43
New User | Posts: 4 | Joined: 07/14
Posted: 07/17/14
09:11 AM

You can do it with another camshaft a couple of ways. You can replace your present camshaft with one of the same specs but with a wide lobe center like 113-114, or go to a bigger at .050 camshaft. Either way it will bring down the cranking compression and lower speed cylinder pressures, allowing you to run pump gas. Have you done a compression test on your motor? If its about 190lbs or less it may run on pump gas. Have you tried running it on pump gas?  

allend43 allend43
New User | Posts: 4 | Joined: 07/14
Posted: 07/17/14
09:12 AM

You can do it with another camshaft a couple of ways. You can replace your present camshaft with one of the same specs but with a wide lobe center like 113-114, or go to a bigger at .050 camshaft. Either way it will bring down the cranking compression and lower speed cylinder pressures, allowing you to run pump gas. Have you done a compression test on your motor? If its about 190lbs or less it may run on pump gas. Have you tried running it on pump gas?  

allend43 allend43
New User | Posts: 4 | Joined: 07/14
Posted: 07/17/14
12:10 PM

You can do it with another camshaft a couple of ways. You can replace your present camshaft with one of the same specs but with a wide lobe center like 113-114, or go to a bigger at .050 camshaft. Either way it will bring down the cranking compression and lower speed cylinder pressures, allowing you to run pump gas. Have you done a compression test on your motor? If its about 190lbs or less it may run on pump gas. Have you tried running it on pump gas?