472-528 hemi

[G-man]

Hi

After hearing Holley are going Bankrupt, i wanted to purchase some carburettors to be prepared for when I get myself a Hemi. If they dont sell them anymore I want to have them, if another company takes over, I want brand new out of the box real deal holleys.

Basicaly here is whats going through my head...

472-528ci at 550 Horsepower. I want maximum torque out of it (650-800 whatever possible). If a certain ci would make more torque than another even though smaller, thats the 1 I would go for. So i am looking for a build between 472 to 528 cubes that will make the most torque (which ever cubic inch that ends up)

Having said that, it also needs to have a very mild cam in it so that when I cruise at 2000rpm it isnt drinking all the petrol as it would with a wild cam. Im not too interested in the most "peak" torque but the most torque on average over the power curve (which makes car faster than peak itself).

Given that kind of engine, what Holley carburettor would be the best?


Would I be best of with a single 4 barrel? or would a cross ram intake such as the original Hemi cars give more torque?

Holley Dominator or Holley HP ?


What size CFM?

Thanks

 

[Meep-Meep]

A novel can be written about the subject of intake tuning - and as a matter of fact it has been. Basically, the longer the intake runner the lower RPM that peak torque will occur. Think the 413 long ram and the leaning tower of power. All the new cars are following this same concept with the curled up intake manifolds, but with fuel injection you don't have to worry about fuel separation so the intake can be whatever shape because it's only moving air.

I'd make the compression as high as you can possibly tolerate on pump gas. It's a HEMI for crying out loud and has the best chamber for proper burn. I'd make use of it even if it means custom shape piston tops!! A long cam CL will help keep the power band wide too. A cross ram with some 600 vac secondary Holleys would be good if you can shrink and divide the plenum. Make a HEMI long ram!

 

[Meep-Meep]

Oh, by the way, I don't think Holley is going anywhere.
http://www.wbko.com/pressreleases/headlines/15559727.html

 

[G-man]

Im going to run around 11:1 compression since we have 98 octane gas in australia basicaly everywhere. Would there be any difference between the 2 at 550hp or not and therefor may aswell go with the best looking setup.

 

[69 Runner]

Not that either will have to, but logic dictates the larger engine wouldn't (shouldn't) work as hard to make 550 as the "smaller" one. I would think there would be a torque difference in the two even with the same HP

 

[Patrick]

The old saying there is no replacement for displacement is true. If you used the same CR the same cam, intake and carburetors the 528 would out power the 472. On the other hand getting 550 horse out of a 426 is a cake walk along with 500#tq. All big mopars have flat tq curves its always been there nature. If you have 500# peak at 4400rpm your going to have 400# at 2000rpm and 475 at 6500rpm. Thats the only reason anything but the rule book couldn't out run us on drag strip.

 

[G-man]

Thanks for that

So basically all Hemis will have an excellent tq curve, wont just have peak but a very high average also.

Well going with 550 horsepower and 650+ tq. If a 426 hemi made 550, 472 made 550, 499 made 550, 477 made 550, 528 made 550, would the 528 still make more torque being bigger though the same power? Thing is I heard something from vegas or something a while ago where they used some odd sort of ci such as (477 instead of the crate 472) and it made HUGE torque numbers, so im just checking here if odd numbers do effect a motor differently, or motor doesnt care, the bigger you go the more torque you get and thats more a less a fairy tale.

Having put that out, Holley DOminators or Holley HP (both at the same CFM) wont make a difference either?

Given that, single plane or cross ram or inline... I know cross rams look the best. but I got 2 different story's on that. Ray Barton told me the Cross Ram would make more "torque" than a single 4, Pro System Racing Carburettors told "BUT I would never use the cross ram manifold for the street, as they are a terribly lazy intake manifold for street use."

Another mopar fanatic said X-rams have very bad fuel distribution, Tim Banning from For Hemis only said Dominators, HP, Cross ram, Single plane at 550hp wont really make any difference so go with what you like and tune accordingly to your application. His reply was "Hi George, cross-ram, good torque, lousy idle quality, not built for mileage. Stage V intake/twin Edelbrocks, looks good, efficient. In the end, just run what you want and tune accordingly. Tim@FHO"

So uhm yeah....

 

[69 Runner]

I have nothing good to say about Ray Barton, and wouldn't believe anything they had to say.

 

[Meep-Meep]

I would put more emphasis on matching the cam, intake and carbs rather than a few cubes of displacement. Sure, a lot of cubes will make a difference (because the only substitute for cubic inches is more cubic inches), but 477 vs 472 vs 426 differences can be more about the rod/stroke ratio rather than just displacement, and that will affect cam selection to a point thereby changing how the engine runs at a particular RPM.

 

[G-man]

ok

I got a guy that really knows how to tune dominators and they end up as efficient as HP Holleys and have more "responsiveness" and better air flow than the HP's (according to him which is true as ive known him for a while to know what he does works as he says)

He hasnt got toomuch experience building Hemis though.

Lets say we go with 528 ci at 550 hp and after maximum torque using dominators...

Is ray barton correct in these 2 emails....

"An all alum 528 wich makes 625hp and 640-650lbs tq start at 20,000.00.This is a single 4 bbl>if you choose the x ram optoin the motor will make more TQ.Call and we can discuss your options.Thanks

then i replied n got

"The cross rams always make more torque.Lets me know we are doing some great deals.Call me"

Or not?

69runner... whats your issue with barton?

What do you guys suggest?

 

[69 Runner]

My issue with them is due to the way they jerked a friend around on a motor. They did all the machine work on a new motor for him, and shipped it with the block missing an oil passage. My bud caught the problem and called them on it. They were insulting and fairly unwilling to do anything about a problem THEY should have caught BEFORE shipping but didn't. After insulting him, they finally agreed to fix the block, but my bud was gonna have to pay shipping back to Barton, then back to him.

It was THEIR mistake. He shouldn't have had to pay shipping on the block for it's repair at all.

They also gave him some bad information regarding some work on it. Barton told him he should have them bush the lifter bores to "correct" their geometry. My bud asked about if this would create problems with oil supply for hydraulic lifters and was told NO.

Guess what. When assembled and run with standard hydraulic lifters, the motor wouldn't make more than about 5200 rpm because the lifters weren't staying pumped up. The reason? You guessed it. The bushed lifter bores were limiting the oil to the lifters.

Ultimately the only thing he could do with this "RAY BARTON WE BUILD THE BEST HEMI **** ON THE PLANET" was to run either solids (which he couldn't du cause it was built for a 1970 application) or run Schubecks (which is what he did, only to have one of the Schubecks fail)

The people at Ray Barton were total ********. Being the "big time" Hemi shop they claim to be, they shouldn't have missed the original problem, they shouldn't have made him pay shipping to have that fixed, they shouldn't have told him bushing the lifter bores would be fine, and they DAMN sure shouldn't have insulted him....especially after the kind of money he spent.

I guess other than that..................

 

[Meep-Meep]

Torque at what RPM? Sure the cross ram will make more torque, but at 4500 RPM or something like that? How about torque at 2500 RPM? Going back to your original requirements it seems that you want a killer street engine that you can drive. Build a custom intake with long runners and port fuel injection.

Here is a very good article regarding a 500 Cad engine, but more importantly it has some solid rules for building engines - yeah-yeah, it's not MoPar, but information is where you find it.

http://www.geocities.com/MotorCity/Pit/9364/guide/Why.htm

 

[G-man]

Thanks Runner. Guess I wont waste a phone call to him then.

Im after the most "average" torque, so when you nail it, the 1 with the most average torque will be the quickest and thats what I am after. I also wanna run Dominators.

Thanks meep also.

 

[Meep-Meep]

I think we would love to know how it turns out. Keep us posted!

 

[george68hemirr]

couple of dominators is cool