So here's the story, Built a 410 ci 360 for an '81 dodge ram mud truck I have(weight 5800lbs) acouple years ago. This spring I put the engine into my challenger, and want to maybe do some top end/ cam, etc over the winter.

The engine was built for a heavy truck, huge tires........now it's in a light car.

Here are current specs..

4.040 bore/4.000 stroke(cast crank)
.232/.237 dur./.576/.584 lift
beehive valve springs
roller rockers
iron ram heads,pocket port, gasket matched
2.02 / 1.625 valves
weiand dual plane ..deep port match
750 speed demon
10.2:1 comp. forged pistons
forged rods


So what I am thinking is going with a cam maybe in the 250 ish range, and a single plane intake.

Higher comp. would be nice(should have gone that route initially anyways), but a thinner head gasket is about all I can do for that, as I am not doing any bottom end.

My heads will really be the limiting factor for cam and intake especially.

Valve spings are installed @ 1.750 height with a 117lb seat press, can be installed at different height to increase spring pressure, and lift shouldn't be an issue, as the coil bind is 1.060.

But any ideas on cam and intake choice that would work best are greatly appreciated.

Have a 2800 stall now, but am expecting to be in the 3400-3600 range with more cam. Tranny will also be upgraded over the winter, shift kit, etc. Rear gears will probably be 3.92. Street tires are 275/60R15, 30" slicks for the track.

Thanks,
Cory.

 

Great looking car!

M1 or equivalent will work nice with 1.75 headers.

Did you get any data from what you built as is?

I stuck some data into the computer and the HP and torque with different cams stays pretty close it just moves around rpm peaks. I figured the IR with the 2.02s flow around 265 at .6 intake / 200 at .6 exhaust. Flowed thru the m1 you will see 230-235 cfms at the valve. Numbers are from memory here so don't quote me. You will make power great power!

Duration sucks up stroke and Ive done a couple of these and they weren't huge rpm lovers even with 8mm valves and beehives. Awesome flat BIG torque curve but not screamers.

Here is ten cents worth:

Strictly strip:
252 / 256 lsa 108 installed at 104 .576/.571. if CR gets to 11.5 plus. I think you need 210 to 220 cylinder pressure at least. And more carb

If street
242/248 lsa 110 installed at 106 .576 / .571

 

The thing is definitely a monster as is, just figured as the engine was built for a little more torque and low-mid range power for a heavy truck, I could use a lot more cam now, and a higher power band in a light car.

I have my rev limiter set at 5800 rpm, and don't usually hit it except for when the tires are spinnin.

I should probably just do the gears and tranny first and see where its at. I believe it only has 2.76 gears, so 3.91's would make a world of difference.

And before I do anything internal, I was also thinking of just trying an M1 with an 800 demon.

I guess everything is always decided on how much a person has to spend.

 

I'd do the same to be honest. I bet the m1 and some tuning will make a huge difference in the upper rpms and you prob wont notice what if any you lose on the bottom end. I would differently throw an inexpensive wide band meter on there before i dropped money on the carb. With the current cam i bet you are still within its working ability. Save the money for tires