Need Some Drivetrain Advice

[Bruzilla]

I have a 1974 road runner that was born a 318 car, now has a 360/727, and that I want to drop a 73 440/727 into. To the best of my knowledge the engine hasn't been modified. I got a free Mopar purple cam with it. It's a P4120235AE, .484 lift, 284 duration, RPM range 2200-5900 stick. I'm not looking for a high RPM quarter-mile car, or a highway cruiser, just a great light to light street racing one that will run on pump gas.

So I would like some suggestions on what to get in regards to an aftermarket intake, cam shaft, convertor, and rear-end gearing. I've already been told the cam doesn't really suit my purposes, but I would like to hear what you guys think would.

Thanks

 

[Meep-Meep]

A 73 440 is a low compression engine (assuming it is built to factory specs) so you will be limited to what cam you will end up with. For good throttle response and drivability on an 8:1 motor you won't have anything crazy. I really like the Edelbrock Perf plus cam in my old FE Ford.

Here is the BB MoPar version
http://www.summitracing.com/parts/edl-2192/overview/

In my Olds 455 powered boat I have this Crane
http://www.summitracing.com/parts/crn-803902/overview/make/oldsmobile

The point is both examples above are low compression (8-8.5:1) engines and they run great!

Here are some possibilities. And you should verify the compression requirements for any of these cams before buying one.
http://www.summitracing.com/parts/lun-10230701lk/overview/make/plymouth
http://www.summitracing.com/parts/sum-k6400/overview/make/plymouth

If you have a stock TQ intake or even the square flange one from a late 60's 440 it will be just fine. Use the money you would spend on that fancy aluminum intake and do the exhaust instead. 1-7/8" headers with a min 2.5" pipe all the way out with low restriction mufflers.

A smaller cam also means a 10" TCI street converter will work great. There may be better options but you certainly don't need anything super loose. You can even go with a low stall high efficiency converter to cut about 200 RPM off the HWY cruising speed. And with a 2.94 or 2.71 gear you will be a comfy FWY flier! Or for more pep out of the hole go with 3.23's.

 

[RustyRatRod]

I posted this one on the other thread.

http://www.summitracing.com/parts/cca-cl21-406-4/overview/make/dodge

If you look, it has a really wide duration spread. This is similar to the Thumpr cam. It will sound good and run really well too. Not too big. Can use with stock rockers and pushrods.

 

[Bruzilla]

We're looking at raising the compression to about 9.5 or 10:1, but until we get the engine apart and find out what we're working with, everything is just a guess right now. Based on the described performance from the previous owner, I'm guessing the engine's been overbored already, and there's no telling what else. My speed shop bubba is saying the stick I have now is actually 228/241 duration at 050, which is the number I should be concerned about, and he's saying it should work fine for what we're doing... but that's all Greek to me.

 

[Meep-Meep]

Well, if you are going with 10:1 CR then that opens up some more options. In my opinion you want to look at lobe separation first to determine the correct cam for the application and the rest usually follows suit. RPM range and compression requirements are also important.

For the street I'd say 112 LS to preserve decent vacuum. And no matter what you do remember that if you don't have a good vacuum signal your carb will not work properly. My car makes 12" Hg at idle with a small cam and 10:1 CR and the throttle response is like a motorcycle. It runs high 12's and will burn rubber until the tires explode. It also runs pretty clean and crisp (with the 750 AFB) and can be driven daily. It only takes a slight cam tweak for a street car to make a difference but many in my opinion like to over cam and then the posts following that big cam installation ask why there is no bottom end response or why the timing needs to be at 50 degrees to make the car idle.