RustyRatRod's Guide To Hot Rod Bliss

PScamp74 said

So, absolutely great stuff, not quite finished with all 1400 pages..lol...but I have a question ❓
Does the motor built for RV applications have a different cam to produce more torque?
And....how well will it perform straight across into my '74 Scamp?? (I know it won't just fall off in there and that there's a lot to do to make it happen), but generally speaking wouldn't it pull the tires off of it just the way it is?
And, I'm doing the same thing in my B body '73 Charger SE... should I go through them and change anything?

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So called RV application, it's not really about more torque. Torque is mainly based on displacement most engines will fall in between 1 to 1.45 lbs-ft per Cid, for most average street builds gonna be more like 1.1 - 1.25 lbs-ft per Cid, if your above 1.2 your doing good, the other mainly way is Volumetric efficiency (VE) how well your filling the cylinder in percentage so basically actual displacement being used which cam among other things effect this.

Now for RV basically doesn't mean more torque but where torque is made, for a street car off idle to 3000 rpm is more important 'rv range' than 3000-5500 rpm street performance range. Most low power/truck type engines have a powerband of idle - 4500 rpm. It's hard overly increase power in the idle - 2500/3000 rpm range the trick with a street type performance engine is to increase the useable powerband from 4500 to 5000/5500 rpm without losing much and or small gain down low idle - 2500 rpm, higher stall deeper gears lighter car etc... Makes that less important. Efficiency is the third way, mainly low restriction intake and exhaust 'pumping loss' Cr there's others but those are the main. So it's about what's more important idle-3000 or 3000 - 5500 and the balance/compromise of the two.

And more direct to your question cam has the biggest role in this.