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car idles fine but stall when i put it into drive

G

GT350

Member
car idles fine but stalls when i put it into drive and blip the throttle,Its all freshly built 351w mild cam. performer intake,600 holley,petronix ign.
If i go easy on throttle it doesnt stall.
 
Bruno is right- accel pump shot weak or late. Too lean an idle will make this worse, but not cause it IME.
 
"Mr. Din" said:
im having kind of the same issues. did you get your issue fixed?
Click to expand...
i done 3 things adjusted floats they were too high,set the mixture also my acc pump diaphram need adjusted after all that car runs fine.
 
Hey GT350,im an absolute newb when it comes to carbs and still a beginner when it comes to stangs so can you explain in detail how i could go about doing the same things you did to ur carb?I have a holly double pumper(4150).Although mine also tends to stall when cold if i dont continuously rev it.Thx
 
"hamburgler" said:
Hey GT350,im an absolute newb when it comes to carbs and still a beginner when it comes to stangs so can you explain in detail how i could go about doing the same things you did to ur carb?I have a holly double pumper(4150).Although mine also tends to stall when cold if i dont continuously rev it.Thx
Click to expand...
this vid will give a basic insight on how floats work

http://www.youtube.com/watch?v=ge-mIk6n ... re=related

and this vid shows you how to adjust idle mixture screws
http://www.youtube.com/watch?v=UPGLUsW5 ... re=related

and this how to adjust acc pump

http://www.youtube.com/watch?v=k-Nx5HEz ... re=related
 
Hmm.. I did some fiddling with my carb today, checked the float levels there we good. Did the idle thing. Car idled a little longer in gear but still would die out after a few mins. I went ahead and ordered a 600cfm DP carb today to replace the big 750 i have in my car. Hopefully that helps out something.
 
Not great so far,i hooked up my vacuum gauge to my manifold port and it read 9 at idle.As i was doing this i was following the carb video and was about to adjust my mixture screws when i noticed there was two mixture screws on one metering block and none on the other,so i was kinda lost after that.I tried to get the model number off my carb 4777-7 but nothing comes up on the holley site.Here are some pics.Can ANYONE tell me if there should be mixture screws on both metering blocks and if not how do i adjust the mixture?Also can anyone tell me how many CFM's my carb is since i cant find much on the holley site.Thx

Picture059.jpg


Picture058.jpg
 
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there are only 2 mixture screws on these holleys,but you still have to adjust both float levels,is your manifold to heads bolts tight you might have a vacuum leak
 
a 4777-1 thru -5 are all 650 cfm's. I don't show a listing for the -7 either but it would be safe to say that it is also a 650 cfm. You sure you are not seeing a -1 (one)? If you have it off then the throttle bores should be 1-11/16 on both the primary and secondaries, and the venturis will be 1-1/4 primaries and 1-5/16 secondaries. If this is what it measures at then yes, it is a 650 cfm.

9 in. is a major indicator that you have a vacuum leak. There are 3 different Holley style square-bore base gaskets. I'd pull the carb and make sure (don't "I think" on this one) that the carb is sealing correctly to the manifold. Also check the (one or two) small vacuum ports on the base plate and the large one in the back used for power brakes to make sure they are all OK.
 
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