carb issue
#1
Member
MASTER JOURNEYMAN
Thread Starter
Join Date: Apr 2005
Posts: 41
carb issue
well guys heres what ive got. sbc 388ci 15.5:1 compression afr210 heads ported by HVH and a HV1 intake 4150 flange ported by same company with a 975 bg gold claw carb sittin on top . cam specs are as fallows .701-.701 lift 269-276@50 112 ls installed at 112. i have a lm1 wide band but the damn thing keeps sending error codes i tryed a new o2 but with no luck i think the brain went bad. the carb comes stock with 86pri and 94 sec jets in it. now i have vp c14 in it for fuel and the damn thing is messin with my head i put 80 in the pri and 86 ins the sec idles great maybe alittle rich but cant tell right now cuz my tools broke, the primary circut is responsive as hell but if i smack the secondaries it feels flat. for squirters im runnin 37 front and back. i tried uppin the secondaries and then it gergels on its self doesint like it. as of right now im lost without going to a dyno and was hoping for alittle help. hopfully somone here has a similar combo and can fill me in on what there running. if theres any other info you need just ask thanks in advance. JUNIOR
#3
Member
MASTER JOURNEYMAN
Thread Starter
Join Date: Apr 2005
Posts: 41
cool let me hit you guys with this also square jetting vs stager whats the benifets. this is a race car but a street race car. i drive it alittle not to much the damn fuel is to expensive. i have no pvs in this carb as of right now. should i square it off or not never squared a carb off.
#4
just a thought...where is your timing set..and is your timing light right..i have seen something close happen like this when the timing retarded...
Brian
Brian
__________________
Bjuice..
"I'M YOUR HUCKLEBERRY ! "
Bjuice..
"I'M YOUR HUCKLEBERRY ! "
#5
Senior Member
EXPERT BUILDER
Join Date: Aug 2005
Location: Tell City, IN
Posts: 356
Without powervalves you need to square it off from what I understand.
When I first did it I had a out of the box 750 with 71 and 80 jets with powervalves and ran 6.90 took them out and with 80's all around ran 6.80-6.83..right off. Since then I have never ran them.. 8)
When I first did it I had a out of the box 750 with 71 and 80 jets with powervalves and ran 6.90 took them out and with 80's all around ran 6.80-6.83..right off. Since then I have never ran them.. 8)
#7
Member
MASTER JOURNEYMAN
Join Date: Dec 2005
Location: Building shelves for wally's
Posts: 36
carb issue
How many turns out do you have the mixture screws?
Try 2 rounds.
How far open are your butterflies?
The transfer slot should barely be showing looking from the bottom of the carb up.
Sometimes the butterflies have too much of the transfer slot uncovered which will make it run rich at idle then go very lean when you whack the throttle because it already using part of the transfer fuel supply while idling.
87-90 jets squared with no PV's should be close on the jetting
Is timing locked @ 38 or do you have an advance in the distributor?
May try locking it, if it's not already.
Have you checked for a vacuum leak?
Good Luck, Mark
Try 2 rounds.
How far open are your butterflies?
The transfer slot should barely be showing looking from the bottom of the carb up.
Sometimes the butterflies have too much of the transfer slot uncovered which will make it run rich at idle then go very lean when you whack the throttle because it already using part of the transfer fuel supply while idling.
87-90 jets squared with no PV's should be close on the jetting
Is timing locked @ 38 or do you have an advance in the distributor?
May try locking it, if it's not already.
Have you checked for a vacuum leak?
Good Luck, Mark
#8
Member
MASTER JOURNEYMAN
Thread Starter
Join Date: Apr 2005
Posts: 41
hey mark my slots are showing about .015 the mixture screws are out 1 turn. i have 78-86 in it now and when i turn the mixture screw in the idle increases. but does not die when i turn it out to half turn it still has a lean stumble apon acceleration i go out to 1 turn and its so damn fat it loads up in about 2 minutes. im thinking the idle feed jets are to big in the blocks . i have 1/8 inch holes drilled in the throttle blades, i had the car running last night and farted around with it i just cant figure it out. i called pat at pro systems and im going to send him the carb next week ive had just about enough with it. nothin like spending 1100. bucks on a carb and it just being a pos. i should have bought a holley hp ultra but i didnt call me a dumb ass. thanks guys i appreiciate everything.