bbc help

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mrfaster1
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Joined: Sun Jul 15, 2012 10:16 pm

bbc help

#1 Post by mrfaster1 » Mon Jul 16, 2012 2:05 pm

I'm having some issues with my 468 it doesn't seem to be running where it should be..I put this motor in a 93 fitz jerold dragster with a glide and a 5000 stall 456 gears on 31.5x14 slicks this rail ran 9.9 with a stock sbc. With that said here is what's in my motor
468 block
14:1 comp
781 ovel port heads 113 closed chamber with bigger valves and port work and gasket matched
Cam is a 294/306@588/593 lift lobe Sep 110. 2800-7000 rpm range
Vic Jr intake
950 alky carb jetted at a 176 now no runs since going bigger jets
144 jets only ran a 10.8@118
Msd 7al2 with a 6800 chip

What am I missing here??/

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John_Heard
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Re: bbc help

#2 Post by John_Heard » Mon Jul 16, 2012 5:23 pm

Should run circles around the stock small block you would think.

You got any data? RPM / etc? Same converter as the small block? Are you blowing through it?

mrfaster1
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Joined: Sun Jul 15, 2012 10:16 pm

Re: bbc help

#3 Post by mrfaster1 » Mon Jul 16, 2012 8:09 pm

Starting at 4500-4700 shifting at 6400

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John_Heard
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Re: bbc help

#4 Post by John_Heard » Mon Jul 16, 2012 9:17 pm

That don't sound converter related.

How much timing you got in it? Maybe your timing mark is way off or something goofy. Low timing will make them run like a turd.

mrfaster1
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Joined: Sun Jul 15, 2012 10:16 pm

Re: bbc help

#5 Post by mrfaster1 » Tue Jul 17, 2012 7:55 am

Set the timing at around 38 deg at 2500rpm
When I changed the jets yesterday I let it run to see how long it would take to come up in temp at 1000rpm it took 11minutes to reach 140 deg intake ice cold..ex temp only got to about 350-375

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supernova
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Re: bbc help

#6 Post by supernova » Tue Jul 17, 2012 8:30 am

IMO,
It sounds like its fat on the fuel and needs more timing. Alky is slow burn and with the heads you have it needs more timing. The 781 are ok for what your using them for but with alky timing will have to be higher, maybe even as high as 50+ deg's.
Start by moving the timing up 2* at a time and see if it get's better ET's. It should drop the ET. Once it starts to slow down back it off back to the deg's that got the best ET and lock it down than you can work on the fuel tuning.
You can read your plugs to tune by also but you have to have a good starting point or you'll chase your tail.
It sounds to me it needS timing and fuel tuning.

NOTE: timing is ET and fuel is MPH.
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
572 C.I. BBC

Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

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