question for chryco psycho

[todd383]

What carb would you recomend on my 383,it was dynoed at 508 HP and 496 ft. lb. TQ. that was with a holley 770 advenger, nice carb but not for my motor, i am running a hugehs 3038 cam and runnin about 8 inches of vac. the problem tat i am havin is it is runnin way to rich at idle, messed around with the carb for a long time, borrowed my friends carb same thing, and it did the same,way too rich,but works great on his, but he has alot more vacume at idle. some one told me if it has adjustable air bleeds, because that may be the problem, but these carbs dont,  could this be?? But any way i want too change the carb anyway, what size would u go and what make, the HP series?? I want the best!!!  anyway the rest of the motor has 10.1 comp. hughes stage 2 ported heads, edlebrock rpm manifold, tti headers and 3" tti exhaust. thanks

[Chryco Psycho]

Hey Todd
Running rich at idle with longer duration cams is typical , the chop you get at idle that sounds so good is cylinders misfiring & dumping raw fuel into the exhaust so ti will always seem rich ....there are 2 tricks that will help ,using smaller idle bleeds will increase vacuum signal at the idle transfer slot & help it idle better , also drilling a small 1/16" hole in the throttle plate will help close the throttle position enough to get the throttle plate over the transfer slot better , as a test you can bend a piece of mig welding wire & insert ti into the outer set of bleeds to see if the car suddenly idles better , most will , now you can either pinch the wire under the squirter & leave it there Or you now have confirmed the car will run better with restricted bleed & go buy a different carb where the bleeds are changable
 My choice assuming you are still going to replace the carb  would be either the Holley 82751 HP street 750 or the Proform 750 , I feel either of these carbs is equal & both will give you better performance & adjustability

[todd383]

Thanks CP, seems that is the answer i am lookin for, the holley 750 HP, I recently spoke to somebody with basicly the same engine set up, and was runnin the 770 advenger,and had tuning problems, but switched to the same 750HP,and picked up almost 20 horsepower, and much easier to tune. That will be my choice, thanks again

[nivvy]

Thanks CP, seems that is the answer i am lookin for, the holley 750 HP, I recently spoke to somebody with basicly the same engine set up, and was runnin the 770 advenger,and had tuning problems, but switched to the same 750HP,and picked up almost 20 horsepower, and much easier to tune. That will be my choice, thanks again

glad you didnt go the edelbrick route.... holleys are the best carbs ever made   

[todd383]