The motor in the race car I am setting up for next year is a 60 over 427 big block alcohol Chevy. It's a fairly mild motor at this point with ~13:1, a solid lifter cam and rectangular port aluminum GM heads. With the cam installed it is good to ~7,200rpm. The carb is a 750CFM Holley on a Vic Jr. and I think it's too small. Something in the 850CFM range would seem preferable. The dilemma is as follows: I am gearing up for a bigger motor for the following year and I don't want to spend much on the old motor. I was thinking that the Predator carb might be usable both with the old motor and the new one, so I could get it this year and move it over to the new setup next year.

I have next to no knowledge about the Predator, but the claims make it seem like it would do the trick. Anyone have any comments or opinions they'd like to share?

Rich

 

IMO they are a PITA to setup. I have used them in my old Jet boat and tried one on my old low 10 sec 5.0 for a while. Throttle response can be extremely good. It worked real well on my jet boat so I tried one on my 5.0. I just could never get it to run right on the car and went back to a holley.The load on the jet boat was vastly different and it seemed to work real well in that application.
Steve

 

Thanks! Anyone else who has used one?

Rich

 

we run two of them of the mud bogg truck. when they work they are dead on and never need touched. You back fire it? And both carbs are done put a fork in it.

Dominators might be a better choice We use them on the mud bogg truck because bouncing and tipping do not bother them much

 

Rich,

A 440 Cube motor, that will spin to 7200 and make power is going to need more than a 850 Holley. I have a 950HP at the shop you can try to see if it works, before you swap to a 4500-4150 spacer and try a Dominator.

Bret

 

Bret: I could probably fumble my way through the calcs, but can you do a quick guesstimate of how much hp I am giving up with a 750 v. a 950? I am more interested in getting the car out fairly inexpensively next year than in setting any records. For the '06 season I am planning a 509 or 540 and I know I will need a Dominator for that if I stay with a carb. So, I don't want to add a carb that I used for just one year to my "pile-o-parts" unless the benefit will be substantial.

It does sound like there is not a lot of enthusiasm for the Predator, right? I also suppose it would be too small for the 509-540 anwya?

Rich

 

I ran one on my 440 Mopar about 15 years ago with great results. The throtle responce was the best of any carb I have ever used. THe set up was not so much a pain as there are just very few adjustments and very limited selections with in those adjustments. The carb is also a pig in terms of hieght, I had to cut a hole in my Chalangers hood and run a 3'' cowl to make room for it and that is in a car with good hood clearance. If I where going to run a carb today I might look at some of the newer companies such as grant and others.

 

I ran one years ago on my old Charger...hated it...never again...

 

Rich,

Carb size and HP go hand in hand. What's the rest of the combination? If we are talking 600hp then 850-950 will work fine, if it's more than that then maybe a 1000HP or Demon will work.

The difference at the top end is around 20hp from a 750-1000 4150 carb, there's probably about 15 average HP there too in the RPM range you are going to run this thing, still the 1000 is not enough carb on a 440 cube motor doing about 600hp and turning 7K. That's just based on trying to get a 1.0" of Hg only and not 1.5 or more.

Kind Demon RS

That with a 4150-4500 Wilson Adaptor Spacer would do the trick, then you can play around with it and find the right size at the track.

I would doubt that the 4150 would work later on the 509-540 anyways, most likely a Dominator would be the likely canidate on something especially with the RPM you are going to want to twist it.

Bret

 

My younger brother runs a 468" BBC, shifts @ 7000 rpm...car weighs 3700 lbs with him in it...it was running 10.7's@129 on motor with a Holley Pro Series 950 carb....

Food for thought...

 

Bret: the current motor is good for low 9's @ 145-150mph in a 2,150lb car+driver combo. It has not been on a dyno but the times/speeds imply ~650hp. I don't think it's worth $1,000 to go just a little faster, given my plans for the following year. The BG RS series was something I didn't think of though! Sounds like thatr may be a good route to consider.

Thanks, Bret, and others who have responded with their thoughts and experiences. I am going to look into the alcohol King Demon a bit more.

Rich

 

Rich,

I figured it was about a 630hp motor or so from what you said and the RPM that it ran too.

The good thing about the BG RS is that it would work for the motor next year too, plus the tuining possibilities are really helpfull at the track.

I talked with Joe Sherman at this years engine contest and since he threw his first Demon on his 2002 EM motor he loves them, that carb found him 10 average on both HP and TQ immediately. That's a pretty good endorsement.

Bret