Stall and gear ratio with MP 284/484

[Stewsta]

Heres what I have
66 Coronet 3800lbs
440 .60 over
MP 284/484. Not sure if its new profile or the old one
10 to 1 flat top pistons
Stock 906 heads
CH4B intake
1 3/4 headers
3310 holley
Im gonna get the complete 4 Seconds flat ignition with recurved distributor

727 w/ B&M 2400 stall

741 3.91 gears sure grip---gears are noisy so im looking at 3.73's if i stick with 741 case
Mini tubbed

forgot to mention the rear tires are 28" tall 295 M/T drag radials

Its seems that opinions are all over the place on what works well with this cam so I wanted to see what I got from you guys. Please no suggestions on using a different cam because its staying. My question pertains to the stall and gears. I planned on keeping the 2400 stall and getting a new 3rd member(742/489) with 4.10's. Will this work well in a street only car. Are 3.73's OK? Higher Stall? I dont care about fuel economy or highway speeds and the highest speed limit in town is 45mph. Im looking for seat of the pants fun stop light to stop light. Thanks

 

[Budnicks]

I think the 3.73:1 will be fine & you will get a little more effective stall speed with out changing the converter, than you had with the 3.91:1 gears, the steeper the gears {higher numerically}, generally speaking, the less effective the stall speed will be, it's mostly because of the torque multiplication, the car will move easier, with the steeper gears, with the 3.73:1 gears {lower numerically} you will flash a little higher, than with the 3.91:1 gear ratios.... IMHFO for more fun/faster off the line, use a 3500-3800 rpm stall converter & 4.10:1-4.30:1 gear ratios, maybe a slightly taller tire for more contact patch {better for hi-way driving too}, would be even better/more fun.... add some Calvert CalTracs & drag radials & it would be a screamer

 

[Kern Dog]

I had that cam in a .030 over 440. It was the second motor I built for the Charger. I ran a 2500 TCI converter and 4.10 gears with a 27 1/2" tire. The car ran strong.... until it threw a rod!
Its a decent cam. I think you'll like it.

 

[Meep-Meep]

Back in the 80's that cam was the kiss of death to a stock engine, which sounds like what you have. IF you have that old profile expect to have poor drivability on the low end and low vacuum. That cam really needs compression, gear and a healthy stall converter. What people didn't realize that even though that cam only has .010" more lift than the hemi grind cam, it is not the same cam as the hemi grind. It has more overlap and the valve events are different. It really is a much more radical cam for the street than most people think. If I were you I'd change the cam.

 

[Stewsta]

For what its worth I bought this fresh rebuild motor/trans from a guy who had it in a 68 charger that he was restoring. He put it up on a lift with it idling for 10 or 15 minutes and it purred like a kitten. He also took me for a ride and it was a hoss. Bare in mind that it was a bare shell of a car with nothing more than 2 seats and drive train but it ran fine with start and stop driving. I will say that out of the hole it didnt dig as much as i thought it would but once it got a little rpm it screamed.

 

[Kern Dog]

Back in the 80's that cam was the kiss of death to a stock engine, which sounds like what you have.

I'd agree if he had a 74-78 stock 8.2 compression ratio. I thought I read that he was at 10 to 1 ?
Any cam with more lift, duration and overlap is going to lose a bit on the low end, but the higher stall converter and deeper gears make up for it. The standard axle gearing for a 440 Charger R/T was a 3.23. Step up the cam specs, step up the rest of the combination and lower ETs will follow.
I had decent idle vacuum with similar compression in my 2nd 440 using this cam. Never had an issue with my power brakes either. It was a bit lopey, but who here doesn't like that??

 

[383man]

We ran the old 284-.484 cam my sons old 383 combo. It was mild 383 with 452 heads with mild bowl blending. The heads were cut for 9.5 comp with the stock pistons and bottom end. Used the RPM intake and a 750 DP. CPPA Headers and 3" pipes. Had a turbo Action converter 3000 stall and 3.91 gears. Car weighed 3550 with him in it. Ran a best of 12.31 @ 110 on McCreary G-60 tires. I used the stock dist I curved for total timing by 2000 rpm and the orange ECU. It really ran good with that combo. Here he is cleaning off some rubber on the 1/4's. Ron