Holley Carb delima build on old or buy something else?

Holley Carb delima build on old or buy something else? - 07/14/09 06:42 PM

So the charger has a new healthy 440 in it and I think the carb is alittle small. The carb is a holley 4150 mech 650 DP with a 750 proform body older 2 corner idle. I raced the car last weekend and ran 12.80 @106, the motor did'nt seem to pull hard on the top end. I run 3.91 gears with a 27" hoosier quick time.
Question is should I trick out the carb I have with AED performance billet base plate and all the cool race accessories, or look for something else. I want to make this thing really run hard.

Anthony

Posted By: MR_P_BODY

Re: Holley Carb delima build on old or buy something else? - 07/14/09 06:52 PM

Time for something bigger and better..... 950dp

Posted By: Bob_Coomer

Re: Holley Carb delima build on old or buy something else? - 07/14/09 06:53 PM

The carb is definatly holding you back some, but isnt costing you as much as you think. What do you have for a fuel system now? It could be running out of fuel on topend, which might tend to fool you thinking its the carb. It would be nice to monitor fuel pressure down the track. Also have you double check total timing etc? I would make sure it was getting plenty of fuel, and the correct timing above 3500RPMS before I spent some money only to find out it doesnt help any.
When Time to upgrade, just pickup one of those $100 ProForm main bodies, and use your old baseplate/linkage, and bowls/metering blocks. Those are very nice and well worth the money.

Posted By: CJK440

Re: Holley Carb delima build on old or buy something else? - 07/14/09 07:04 PM

Looks like he already has a proform 750 body which I think is supposed to flow 800+ because it has no choke horn.

Posted By: 440charger500

Re: Holley Carb delima build on old or buy something else? - 07/14/09 07:56 PM

My fuel system is a new factory tank with new 3/8 fuel line and a carter hp pump. I have a holley adj fuel regulator set a 6 psi. I'm wondering about the base plate. The carb was a stock 650dp before I installed the proform 750 bodie. I'm thinking maybe I could just add a billet base plate with larger venturies, that should make the carb larger right?

I'm on a slight budget also. So I trying to figure out what might help the most for my money.

Posted By: HotRodDave

Re: Holley Carb delima build on old or buy something else? - 07/14/09 07:58 PM

A carb spacer could help determine if a bigger carb might help. The extra plenum makes the carb apear bigger to the engine by buffering and smoothing out the pulses some.

Posted By: MR_P_BODY

Re: Holley Carb delima build on old or buy something else? - 07/14/09 08:06 PM

The best thing to do right now would be to mount a
gauge and see what it says(at the top end of the track)

Posted By: CJK440

Re: Holley Carb delima build on old or buy something else? - 07/14/09 08:08 PM

Quote:

I'm thinking maybe I could just add a billet base plate with larger venturies, that should make the carb larger right?

The Venturis are in the main body.

Posted By: RemCharger

Re: Holley Carb delima build on old or buy something else? - 07/14/09 08:39 PM

How big is the cam? Quite possible you won't pick up much if thats all the motors got.

Posted By: forphorty

Re: Holley Carb delima build on old or buy something else? - 07/14/09 10:58 PM

give us a few details. You might consider working on getting it to leave harder before you worry about upgrading your carb. At 106 mph you should be in the 12.40 range.

Posted By: 440charger500

Re: Holley Carb delima build on old or buy something else? - 07/15/09 12:22 AM

Ok how about I give the engine set up:
440 .40 over
KB pistons -3.5 cc dome 10.25 to 10.5 compression
Ported 906 heads stock valve size
Isky 1.5 iron rockers bushed w/stainless shafts
RPM intake gasket matched
Thorly 1 7/8 headers
Comp 285HL cam

The car is set up with:
3800 Dynamics converter
8 3/4 3.91 gears pinion snubber
90/10's front /Rear Mopar drag shocks
ESPO Extra heavy duty springs
Ya and the car is heavy @ 4000w/driver

Posted By: Thread Ender1

Re: Holley Carb delima build on old or buy something else? - 07/15/09 12:38 AM

Question on the proform main bodies, I have a 700 DP #4778 whats the max i can step up to with my metering blocks and base plate?

Posted By: BSB67

Re: Holley Carb delima build on old or buy something else? - 07/15/09 12:50 AM

Quote:

Ok how about I give the engine set up:
440 .40 over
KB pistons -3.5 cc dome 10.25 to 10.5 compression
Ported 906 heads stock valve size
Isky 1.5 iron rockers bushed w/stainless shafts
RPM intake gasket matched
Thorly 1 7/8 headers
Comp 285HL cam

The car is set up with:
3800 Dynamics converter
8 3/4 3.91 gears pinion snubber
90/10's front /Rear Mopar drag shocks
ESPO Extra heavy duty springs
Ya and the car is heavy @ 4000w/driver

For what you have, the hp (i.e. mph) seems off. As others have said - first check the fuel pressure all of the way down the track.

Posted By: 440charger500

Re: Holley Carb delima build on old or buy something else? - 07/15/09 01:10 AM

I'll have to get another fuel gauge to rig up so I can see it going down the track. The engine only had about 150 miles on it so I didnt push it hard. I shifted @5500 rpm. I think there is another race in 2 weeks, off to the summit catalog.

Posted By: Joshs68

Re: Holley Carb delima build on old or buy something else? - 07/15/09 01:26 AM

I rebuilt a carb for my charger,
I had the cost of the old carb, the cost of the rebuild kit , all my time in the process.
I tried a Bigs 950 new and setup for my car, WOW is all I can say, I have almost even money in the two carbs, but I wish I would have just gone this route in the first place. shop around , deals are out there.

Posted By: toddd

Re: Holley Carb delima build on old or buy something else? - 07/15/09 01:32 AM

Have you tried to borrow another carb to try before you spend your $$$$$.

My vote is for a 950HP

Posted By: 440charger500

Re: Holley Carb delima build on old or buy something else? - 07/15/09 05:15 AM

I just discovered BIGS carbs, looks good but I just have'nt heard much about them.

Posted By: RemCharger

Re: Holley Carb delima build on old or buy something else? - 07/15/09 03:54 PM

Quote:

I'll have to get another fuel gauge to rig up so I can see it going down the track. The engine only had about 150 miles on it so I didnt push it hard. I shifted @5500 rpm. I think there is another race in 2 weeks, off to the summit catalog.

I think theres more in it with more rpm...but that might lead to a single plane intake and I don't want to offend the RPM guys out there....

Posted By: 440charger500

Re: Holley Carb delima build on old or buy something else? - 07/16/09 05:53 AM

Well tonight the 440 got a taste of an 850DP annular carb. It seemed to really run. Now I need a test&tune night at the dragstrip. The fiber glass plant down the street is probably getting tired of me using there staight-away.