Carb for a street/strip stroked 440

[68-500]

Price of a new carb maybe halfway to a better mannered camshaft. Then you may not even need a new carb.
You can also adjust the accelerator pump cams and a different power valve might fix your fuel issues.

 

[BSB67]

What exactly does “…the DP throws too much gas off idle” mean? Based on what you have, it’s more logical that your problem is being lean

If you cannot get the 4781 to work on what you have, it’s kinda hard to imagine you’re going to get an Eddy 800 to do better.

 

[RemCharger]

What exactly does “…the DP throws too much gas off idle” mean?

 

[autoxcuda]

My experience has been that cams with that much duration don’t play well with carbs that have street calibrated low speed circuits…….and “two corner” idle.

Do you think on of those EFI setups, Holley Sniper 2, could handle it?

Would it still be tough to tune with that cam?

 

[PRHeads]

That’s a question for the Sniper forums.

I can tell you this, if I’m selling a cam to someone with that style of EFI set-up, it gets a lot less duration than what the OP’s cam is.

I prepped some Indy heads and supplied a HR cam going on a 505 for a local shop a couple of years ago.
It was dynoed with a new 1050/4150 carb(don’t recall if it was a Brawler or QFT) that required minimal tweaks to get dialed in.
The owner of the engine/car was not at all a hands-on guy, and just didn’t like the carb.
The 440 this 505 replaced had some sort of EFI, so they installed a Sniper in the car.
It took quite a bit of tuning to get it to drive decently.

That cam was only a 246/251-110.

Imo, a carb swap isn’t likely going to get the driveability to where the OP is actually “happy” with it.
He’ll either get used to it………or change the cam.

The appropriate cam would totally transform how the car drives.

All that being said, my first move would be to put a (genuine Holley) kit in the current carb.

 

[autoxcuda]

My buddy deals with those EFI's and they seem to reduce HP some and take multiple trips to the turner. Says they start nice.

"perception is reality" so they say.

 

[OMTWF-72SE]

Do you think on of those EFI setups, Holley Sniper 2, could handle it?

Would it still be tough to tune with that cam?

Absolutely not a Sniper 2, the "auto" tuning would be a challenge with that cam. They are best for street builds. They like target AFR. That's why I mentioned the Holley Terminator. You can auto tune, or a good tuner could create multiple tunes to store on the sd. Set up the right distributor controlled by the efi and it might just be ok in traffic.

 

[not so famous bob]

Absolutely not a Sniper 2, the "auto" tuning would be a challenge with that cam. They are best for street builds. They like target AFR. That's why I mentioned the Holley Terminator. You can auto tune, or a good tuner could create multiple tunes to store on the sd. Set up the right distributor controlled by the efi and it might just be ok in traffic.

fast 2.0 fuel inj. , 1200 cfm throttle body: my cam is a little hotter than his is , and I had to downsize the original cam to lower my map readings .
Go figure ,1200 cfm , and cant run a big camshaft !!

 

[gtxrt]

iron or alum heads ?

 

[SlinktRR]

The AVS wont solve anything. Just change the cam.

I run a comp xs290s solid flat tappet in my 499, street car with a six barrel and trick flow heads but I have run an 800 AVS and a brawler 950 on it previously. AVS is too small, brawler was great but if I ever ditch the six pack I would not be opposed to an 850 DP. that is what it was dyno'd with and it did 600hp/625tq.

the 290 cam specs are about as high as I would go for a "streetable" stroker. 252 at .050 intake, 290 advertised duration. I think comp discontinued the Chrysler BBM grind but there are plenty of others with similar numbers.

 

[JARRETT LYNCH]

The AVS wont solve anything. Just change the cam.

I run a comp xs290s solid flat tappet in my 499, street car with a six barrel and trick flow heads but I have run an 800 AVS and a brawler 950 on it previously. AVS is too small, brawler was great but if I ever ditch the six pack I would not be opposed to an 850 DP. that is what it was dyno'd with and it did 600hp/625tq.

the 290 cam specs are about as high as I would go for a "streetable" stroker. 252 at .050 intake, 290 advertised duration. I think comp discontinued the Chrysler BBM grind but there are plenty of others with similar numbers.

Are you running power brakes or manual?

 

[PRHeads]

“I think comp discontinued the Chrysler BBM grind but there are plenty of others with similar numbers.”

The Comp XS290S 3 bolt is currently in stock:

https://www.compcams.com/xtreme-energy-252-260-solid-flat-cam-3-bolt-for-chrysler-383-440.html

 

[SlinktRR]

Manual brakes, about 11-12 inches vacuum. I could only find the Chevy xs290s for some reason, I've had my cam for about 8 years and it runs well with occasional valve adjustments. I would recommend for a streetable stroker.motor.

 

[not so famous bob]

iron or alum heads ?

Alum.

 

[dammstrate]

Well obviously a lot of people with way more experience than I have regarding carbs and camshafts. Seems some say the AVS will be OK, others say it will be worse or no different. Some say "just change the cam", well easier said than done, that's what I have to work with, no plans or ability to change it any time soon. No PB, no vacuum advance, so vacuum not really an issue.

I didn't say anything was running poorly (that I can tell by seat of the pants), although the car is a bit hesitant out of the hole (I probably suck as a driver), could be a number of reasons. But then the car screams all the way to close to 6 grand. I doubt I will race it at the track anytime soon (only Brainard is near me, 2 hours drive). I have read in several places that running a double pumper on the street is not good due to too much gas off idle which can wash down the cylinder walls and create damage over time. Sure call me an idiot of that's not true, but I have read it in several places.

Maybe I just don't like Hollys as I don't race.

 

[PRHeads]

It’s your car to do with as you please.

It’s one of those “master of your own destiny” things.

If you really think an AVS is what you want on there…….just order it up.
No one on the forum has to like it.

Try it……..then we’ll all know.

One of 3 things will be true:
- it will run better
- it will run worse
- it will run the same

There is really only one way to know how it would play out.

 

[dammstrate]

It’s your car to do with as you please.

It’s one of those “master of your own destiny” things.

If you really think an AVS is what you want on there…….just order it up.
No one on the forum has to like it.

Try it……..then we’ll all know.

One of 3 things will be true:
- it will run better
- it will run worse
- it will run the same

There is really only one way to know how it would play out.

Yes, certainly. But I was hoping there would be some kind of consensus about the question I posed. I learned a lot from the thread, but no easy direction to follow.

 

[SlinktRR]

Any carb will do that if the jetting and idle mixture is not set correctly. If you don't want to change the cam, just learn to adjust the carburetor you have. Hesitation off idle..probably lean jetting or insufficient accelerator pump shot. Good luck with your carb tuning journey.

I don't race either and I don't like holley the company but I have found the Mopar six pack setup to be the most rewarding induction to work on. I love it. If you don't want to learn your carburetor setup, go to a shop and have them give it a try.

These days I only trust myself to work on my car's carburetors as most places really don't know any more than you do if you just tinker with them for a while. It's not difficult, just takes time.

 

[BSB67]

I have read in several places that running a double pumper on the street is not good due to too much gas off idle which can wash down the cylinder walls and create damage over time. Sure call me an idiot of that's not true, but I have read it in several places.

What places did you read this? Please share the sources.

Can you describe why a double pumper gives too much gas off idle?

 

[BSB67]

Yes, certainly. But I was hoping there would be some kind of consensus about the question I posed. I learned a lot from the thread, but no easy direction to follow.

You’re kidding, right? There is almost never consensus on anything in these forums, especially on carburetors.