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nova2206
08-19-2008, 11:56 AM
I have a 3550 lb 67 Chevelle with a 477ci BBC with a 400th and a 411 gear.It runs awesome but burns way to much alchol, sometimes 4 gallons a pass,1/8th mile,It looks to be about a 850 carb and would like to know if anyone has any idea of what jets should be in it? It dynoed 715 horses at the wheel..I changed the oil after about 10 passes and it had about 3 gallons of alchol in it.


thanks
hammertime
08-19-2008, 12:44 PM
I have a 3550 lb 67 Chevelle with a 477ci BBC with a 400th and a 411 gear.It runs awesome but burns way to much alchol, sometimes 4 gallons a pass,1/8th mile,It looks to be about a 850 carb and would like to know if anyone has any idea of what jets should be in it? It dynoed 715 horses at the wheel..I changed the oil after about 10 passes and it had about 3 gallons of alchol in it.


thanks


What brand is it ?

168-174 jet is where I'd be, 1 1/4 turns out on idle screws. Your using wayy to much alky for sure.
curtisreed
08-19-2008, 01:04 PM
468 W/850 Rupert 168'S. Same engine w/ 950 HOLLEY HP 172'S. Right around 700hp. Maybe 2 gallons 1/8 mile. Long drive back to the pits from the end at our track. Look real hard at the needle and seats, regulator all of that. Is this a belt drive pump or electric?

Curtis
nova2206
08-19-2008, 02:14 PM
It's a Holly, I know the front has 180s but havn't took the back off, there either the same or bigger..The system is fed through electric pumps.It has APD fuel blocks so where can I get jets for these?
cepx111
08-19-2008, 10:46 PM
#3 gallons plus the oil? WTH? You must had to have been real close to hydralicing that motor man. You got lucky on that one.

Slap some 168's in that carb square and be done. >Cp
hammertime
08-20-2008, 02:22 AM
It's a Holly, I know the front has 180s but havn't took the back off, there either the same or bigger..The system is fed through electric pumps.It has APD fuel blocks so where can I get jets for these?

It has apd fuel blocks ? APD does use a holley main body are you sure its not a APD carb ? Is it over powering the needle and seats leaking into the motor at idle ? The carb will take a std holley jet. I'd put 168;s in both and go.
nova2206
08-20-2008, 08:32 AM
Yeah it's a holly with apd blocks..I'll try to find some jets..
hammertime
08-20-2008, 09:11 AM
Yeah it's a holly with apd blocks..I'll try to find some jets..

odds are its a APD then because they dont sell just the blocks. Where is the idle screws set at ?
nova2206
08-20-2008, 11:01 AM
No it clearly says HOLLEY on both ends..Probably go to gas, I have a fairly new 1000+ Holley ready to go,Thanks for the help.
hammertime
08-20-2008, 11:10 AM
No it clearly says HOLLEY on both ends..Probably go to gas, I have a fairly new 1000+ Holley ready to go,Thanks for the help.

On the sides of the metering blocks does it say APD and on the carb itself says holley ?

we can get this right if u want to work with it.
Answers the next few questions
Fuel Pressure
Timing
Air bleeds
Idle Mixture Screw setting
rear jet
curtisreed
08-20-2008, 12:28 PM
Or I'll give ya 250.00 for it. Save you all kinds of time. :P :P

Curtis
dparker
08-20-2008, 01:16 PM
Dont give up so fast your not burning that much fuel because you jets are to big, which they probably are. Using that much fuel, means its going past your needle sets.
1. Are your needle sets titanium? They need to be for alcohol.
2. What is your regulator pressure set at? Needs to be less that 7.5.
3. If you have a big fuel pump it may be pushing past your regulator.
You need a good regulator for a high flow fuel pump or you'll get whats called creep. Thats where your fuel pressure gradually creeps up until it overruns your needle set. Check these three things before you give up on alcohol.
Good luck,
Dean