carb questions

[302coupe 10]

Ive come to the conclusion that a lot of my engine and acceleration probs are coming from my carb but im confused about a few things.My carb is a holley 4bbl DP carb number 4777-7,which i cant find on the holley site.And the carb only has mixture screws on one metering block,is that right?Im starting to think this car will never run right in my lifetime hehe,thx all

 

 

[302coupe 10]

Ive come to the conclusion that a lot of my engine and acceleration probs are coming from my carb but im confused about a few things.My carb is a holley 4bbl DP carb number 4777-7,which i cant find on the holley site.And the carb only has mixture screws on one metering block,is that right?Im starting to think this car will never run right in my lifetime hehe,thx all

 

 

[ashleesmach1 28]

your carb is a 650 dp and yes is has only mixture screws in the front. It looks like it may need a rebuild

[ashleesmach1 28]

your carb is a 650 dp and yes is has only mixture screws in the front. It looks like it may need a rebuild

[Fordrevhead 29]

I would start with a power valve, looks like it's been backfiring!

[Fordrevhead 29]

I would start with a power valve, looks like it's been backfiring!

[302coupe 10]

Yup she backfires a tad,flames come out of the carb at times too,isnt that normal?A rebuild is probly a decent idea but before that i need to try to get it dialed in correctly to determine what kind # PV i need.Isnt it supposed to have mixture screws on both metering blocks?

Edited June 9, 2011 by 302coupe

[302coupe 10]

Yup she backfires a tad,flames come out of the carb at times too,isnt that normal?A rebuild is probly a decent idea but before that i need to try to get it dialed in correctly to determine what kind # PV i need.Isnt it supposed to have mixture screws on both metering blocks?

Edited June 9, 2011 by 302coupe

[ashleesmach1 28]

I have the same carb and, no it does not supposed to have mixture screws on both metering blocks just the front block.

[ashleesmach1 28]

I have the same carb and, no it does not supposed to have mixture screws on both metering blocks just the front block.

[LiLMike 42]

I had a 66 Fairlane with a 390 and a Holley 600 cfm on it years ago. Had a lot of the same problems you are having. Rebuilt the thing and could never get it right. Ended up going with an Edlebrock and that cleared up all my problems.

[LiLMike 42]

I had a 66 Fairlane with a 390 and a Holley 600 cfm on it years ago. Had a lot of the same problems you are having. Rebuilt the thing and could never get it right. Ended up going with an Edlebrock and that cleared up all my problems.

[CarZombie 25]

I had Holleys during my younger days. I never, never, never, had any luck with them. They all ended up crapping out and causing all types of problems. I went back to stock from Pony Carbs (link: http://ponycarburetors.com/). I can not say Pony carbs/stock is the best, and alot of people like Holley, but for me never again.

[CarZombie 25]

I had Holleys during my younger days. I never, never, never, had any luck with them. They all ended up crapping out and causing all types of problems. I went back to stock from Pony Carbs (link: http://ponycarburetors.com/). I can not say Pony carbs/stock is the best, and alot of people like Holley, but for me never again.

[302coupe 10]

Ye i keep hearing holley's are real tough to deal with but im gonna rebuild it and at least give it a fair chance before i swap it out.thx for all the replies.

[302coupe 10]

Ye i keep hearing holley's are real tough to deal with but im gonna rebuild it and at least give it a fair chance before i swap it out.thx for all the replies.

[jholmes217 65]

If you rebuild it yourself, I highly recommend you get an actual Holley kit. I've gotten other kits (NAPA for one) and they are not the same quality and had a noticable impact on performance. For example on the NAPA kit, the power valve gasket is triangle shaped instead of round, the passages on some of the other parts are smaller, so things don't flow the same.

[jholmes217 65]

If you rebuild it yourself, I highly recommend you get an actual Holley kit. I've gotten other kits (NAPA for one) and they are not the same quality and had a noticable impact on performance. For example on the NAPA kit, the power valve gasket is triangle shaped instead of round, the passages on some of the other parts are smaller, so things don't flow the same.

[LoneWolf2U 136]

Yes get a Holley kit and rebuild it and No backfiring out the top is NOT normal.

 

While the carb is off, get a 4 hole 1in spacer to place under it.

You will get better low end and throttle responce from it with it installed and it will be much easier to set.

 

Holleys are simple once you know what to turn and how to set them up to the eng its sitting on top of.

[LoneWolf2U 136]

Yes get a Holley kit and rebuild it and No backfiring out the top is NOT normal.

 

While the carb is off, get a 4 hole 1in spacer to place under it.

You will get better low end and throttle responce from it with it installed and it will be much easier to set.

 

Holleys are simple once you know what to turn and how to set them up to the eng its sitting on top of.

[ashleesmach1 28]

Use this kit http://www.summitracing.com/parts/HLY-37-485/ Soak all but the plastic parts in a gallon can of carb cleaner with the strainer. Then use air compressor to blow out all the passages. and let dry, then reassemble. don't over tighten any screws. turn mixture screws out 1 1/2 turns initially. set float upside down with it being half way in the bowls. leave the idle screws set where they are. holley has a dvd that has videos to help if you want to purchase it, you can get this from summit too. Good luck

[ashleesmach1 28]

Use this kit http://www.summitracing.com/parts/HLY-37-485/ Soak all but the plastic parts in a gallon can of carb cleaner with the strainer. Then use air compressor to blow out all the passages. and let dry, then reassemble. don't over tighten any screws. turn mixture screws out 1 1/2 turns initially. set float upside down with it being half way in the bowls. leave the idle screws set where they are. holley has a dvd that has videos to help if you want to purchase it, you can get this from summit too. Good luck

[302coupe 10]

Hey,Ashlee,thats the exact kit ill be getting from a local,but first i was told to spray some wd40 round the carb intake connection to see if i have a vacuum leak.I have found some decent videos on youtube but i found one on a site with V8 in the tile,cant recall right now,that is pretty much the best ive seen for a car newb like myself.

 

I dont think ill have enough clearance for a 1" spacer but ill check it out.First im gonna get tuned up right without the rebuild kit and see if that makes a diff,but im thinking my primary jets are maybe too small.Im basically trying to gauge what i need before making many small orders for the sake of shipping costs.

[302coupe 10]

Hey,Ashlee,thats the exact kit ill be getting from a local,but first i was told to spray some wd40 round the carb intake connection to see if i have a vacuum leak.I have found some decent videos on youtube but i found one on a site with V8 in the tile,cant recall right now,that is pretty much the best ive seen for a car newb like myself.

 

I dont think ill have enough clearance for a 1" spacer but ill check it out.First im gonna get tuned up right without the rebuild kit and see if that makes a diff,but im thinking my primary jets are maybe too small.Im basically trying to gauge what i need before making many small orders for the sake of shipping costs.

[302coupe 10]

Alright so im adjusting my floats and i notice my changes arent having any effect soooo i take a look at the float bowl screw and nut,the nut has no threads??so whats its purpose?well i tried to load pics but photobucket is being pissy.

 

I found the link to the great carb tuning vid ,http://v8tvshow.com/content/view/110/28/

 

Video is GREAT for beginners.

Edited June 10, 2011 by 302coupe