Someone mentioned to me that there are some camshafts that are spec'd out for Mopar small blocks with manual transmissions that are good for auto trans applications. Thoughts?

Such as the cam that came in the 340s with the 4-spd in 1968. With the proper torque converter it'll work better.

Thanks Tom!

My friend referenced the 68 340 4-speed cam...

I was told to investigate Comp: 20-222-3 with a stock converter and 3.23-4.10 gear.

Thoughts?

What engine, and what car are you using/thinking of?

A looser converter will help a lot with the bottom end/launch, as it allows that cam to get up into it's power band/torque rpm range, either from a stop sign or at the track. When I did the swap I had a stock 318 converter and the bottom end sucked royally. The top end was great. The car was a '71 Sebring, and bit heavy but it was what I had. I used the same cam in the original stock 318, then in a 273 out of a '66 Barracuda S. It also had 3:55 and 4:10 rear gears. The lower gears didn't help much. The engine also had a torquer intake, I should have used an LD340 intake, or a Performer intake now that those are made.


I'm not at all familiar with the Comp: 20-222-3 cam.

i installed a 340 hydraulic, stick cam in a 74 truck 318, rest of engine stock with the exception of a 318 intake port size "streetmaster" intake with a 500cfm "eldebrock" [] carb and a 2 1/2" duel exhaust coming from 73 A body 340 manifolds. this combo was dumped into a 72 duster with 904/2.96 rear/ 225-70-15 [almost 27" diameter] tire combo. runs very strong and has a nice, semi-lumpy, idle and gets 18mpg. pretty good combo in my estimation. it still needs a super tune with timing [both vac and mechanical] and carb adjustments, so it should be better still.

It's for a 70 Duster with a 727 with possibly a stock torque converter that came out of a 69 Dart (I was told those were good?). I had a new ring gear installed on it. If not, I have an A&A torque converter 2,500-3,000. As for the gear, I'm considering a 3.55 or 3.73. Thoughts?

Comp cam referenced is 218/224 @ .050 with .462/.470 lift, 110 CL (262/270 advertised duration).
276/284, .444/.453 are the '68 340-stick specs.
Here you see the general difference between old & more modern profiles.
I'd prefer the Comp grind, and if it had a bit more lift it would add power with little to no side-effect, probably fine with stock converter.
The SBs are pretty happy with more gear, though if you do a lot of highway driving with a 28" tire or shorter, you'll find it kind of "busy".
My last street SB was 406" with an Engle cam, 214/224 & .470/.504; ran great with stock converter, 3.21 gear & 28" tire; idled nicely even with AC on, pulled 17MPG highway, was very responsive at any speed. Sounded kinda rumpity but was very well-behaved. Obviously, 60 more CI "absorbed" some cam timing, but I think you'll get the ides.

"In general" larger numerical gears & higher stall torque converters helps automatics run well with "stick shift" cams.

I'm going through the cam selection thing with my big block right now....you will get more opinions than there are days of the week. The only "real way" to pick one would be to test several cams in your motor, but you probably don't want to buy 6 cams for testing (I sure don't).

So, what do you want from this car/motor? Highway driving? 1/4 mile drag racing? Commuting to work? What are the specifics of your engine?

Again, "in general" the stock converter, smaller duration cam @0.050" and smaller numerical gears are best for highway cruising. Your A&A, larger cam & the 3.73's would be a good 1/4 mile combination. Commuting in the car would be better off with 3.23's, a converter somewhere in between the two you have....maybe the stock one. All of this "in general".