440 Six Pack vs Gen 3 Hemis

[HP2]

A core issue with any number of cam providers, Edelbrock included, is that they use a cam with a base lobe design to match the smaller chevy sized lifter, which limits its ramp speed. Chrysler and AMC used larger lifters than Chevy and Ford and these larger diameter lifters will tolerate fast ramps speeds on the cam. This means the Chrysler specific cam lobe can open the valve quicker and hold it open longer and shut it faster than an equivalent Chevy style lobe. All of this motion translates in to better cylinder filling, and more power.

You may see advertising saying they use real Chrysler cams. This is the logic behind that statement.

[Spartan040]

A core issue with any number of cam providers, Edelbrock included, is that they use a cam with a base lobe design to match the smaller chevy sized lifter, which limits its ramp speed. Chrysler and AMC used larger lifters than Chevy and Ford and these larger diameter lifters will tolerate fast ramps speeds on the cam. This means the Chrysler specific cam lobe can open the valve quicker and hold it open longer and shut it faster than an equivalent Chevy style lobe. All of this motion translates in to better cylinder filling, and more power.

You may see advertising saying they use real Chrysler cams. This is the logic behind that statement.

Good info, thanks. However I wasn't planning on using an Edelbrock cam, just the Pro Flo XT manifold and some EFI parts

[Spartan040]

This is interesting. I'm planning to go with a Gen 3 Hemi later also, but I have never driven one, and I really like a lot of torque. I did run a 6-71 blower on a 440 in the mid 80's with 2 Carter 750's and the fuel economy was not bad at all, I measured 21MPG at best, that was driving a long stretch at Highway speed, 3.23 gears. But city driving was another story. Gonna look for those recommended threads also. I guess I really need to drive a new Hemi before I decide.

I drove a 2015 Challenger R/T Scat Pack with the 392 Hemi in it the other day, 485 horses is really fun  it's definitely a great motor

[Spartan040]

I'm pulling this thread back into the light of day, had more questions. If I have an A518 transmission, a 440 lightened with aluminum parts, EFI, headers, Voodoo cam with a custom grind, and the properly ported heads. Chryco, you said the engines like this that you built got around 18-20 mpg and about 400 whp? How much power would I gain, and would I lose any fuel mileage, if I decided to build it for lower compression and put on a turbo, twin turbo or F2 Procharger? Pros and cons to those different systems?

[ChallengerHK]

One thing that I don't think was discussed upstream: a 518 trans has a small block bellhousing. To use it with a big block you'd have to have that bellhousing cut off and have a big block bell installed. I think the brand name for that is Ultrabell.

[Spartan040]

One thing that I don't think was discussed upstream: a 518 trans has a small block bellhousing. To use it with a big block you'd have to have that bellhousing cut off and have a big block bell installed. I think the brand name for that is Ultrabell.

You are correct, I looked into that when I was researching transmissions

[Chryco Psycho]

IMO a Turbo should not affect fuel Milage significantly if you can keep your foot out  of it 

[Spartan040]

IMO a Turbo should not affect fuel Milage significantly if you can keep your foot out  of it 

LOL, that's the real trick isn't it

[HP_Cuda]

That dang fun pedal.....

 

[jimynick]

Further to your comments about an O/D trans and it's issues. If I was going to go auto O/D, I'd buy the setup where they use an UltraBell mated to a 60 or 80E GM trans. Like it or lump it, you've got to give the General his due when it come to O/D autos and the ability to get it serviced nearly universally doesn't hurt either. I think there was a thread about this somewhere, but I'll be damned if I can remember where and someone will have done it and may be able to chime in with their level of satisfaction regarding the whole thing. Good luck.