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Old 02-09-2013, 11:53 AM
ghaddon ghaddon is offline
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355 sbc first start issues

Just rebuilt my sbc
4 bolt block
10:1 compression
64cc heads
190cc intake runners
.500 cam (custom spec from Crower) flat tappet
holley 1850-5 carb (supposedly new but no proof)
fuel is 25% vp110 leaded 75% 91 pump gas

ran electric fuel pump to prime carb, set at 7.5psi
motor started right up and brought up to 2000rpm for cam break in, lots of backfire and poor throttle respose to varry rpm, engine died when i barely slipped on the throttle with my finger. Didn't want to restart but also I didnt want to crank forever and kill my new cam... 12v to dist is good. Thought it was a fuel issue so ran the pump and got it to stay steady pressure running fuel into a gas can. It wasn't running well enough for me to check timing but here is how i set it up on the engine stand. Set timing pointer at 8BTDC and ran pointer right at cyl number one and gave it a slight turn of advance. Should be 10 or 12 i would guess. Am i wrong in my method?

I have also been told that this carb is bad for a low vacuum large cam motor. I am running no vacuum advance on the dist. the tranny is a very very built th400 with a full manual valve body. Point being there are no vacuum lines used in the build. What is my next step? I need to get this cam and lifter set broke in properly, is it possible i set up with valve lash to tight and now that it has run it is acting like it has tight valves? my motor experience is with 250f motocross engines. I have built numerous 40+hp 250cc bikes I raced but this is my first experience with a v8.

thanks for the help! This site has been a huge help in my build
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