AJ's Opinion; my super-fun, 360/A-833/3.55 street-combo
Cranking compression about 120 psi
This here is a big problem and this will also show up as in lack of stall.
What elevation are you at.
This here may also point to a "bit of a cam" as they say.
All in all, disappointing results around town; am I right?
Working the Wallace Calculator in reverse, I get to 120 psi with a 340 cam in an 8/1 360 at about 1000 ft elevation.
The VP looks like 100 so, as you say; "pretty sickly".
If that's right, then performance might begin at 3600 rpm, say about 32mph; does that sound about right?
I know exactly what to do about it but it won't be cheap. You gotta fix the low cylinder pressure.
Fun starts at a VP of 130/135, doesn't get into full swing until VP of 140/145. And with iron open chamber heads you won't get much past that, on account of you'll be close to the detonation threshold with best pump gas.
In addition, you have the wrong cam for your gears and application.
After you get the pressure up, and the cam down, you will see the Convertor stall a lil higher; maybe enough to satisfy your need for tirespin.
if you want a fun car, you need to be able to use up all your power by the top of second gear. With 3.23s, and 26" tires, 60=4000 or so, so you don't need anything more than a factory 318 cam. In fact, I can guarantee you that putting a 318 cam into your 360 will increase the pressure and simultaneously bump the VP up to the very low end of the fun category, with no other changes. Sure it will run out of power early, but with 3.23s this will not happen until after 60 mph; so who cares! especially if the 318 cam busts the tires loose, and you can wind her up and maybe keep the tires spinning thru all or most of, first gear; that's the fun part right?
I already found this out in the 70s when I did almost exactly that. I installed a complete 318 topend, including heads, cam, and 2bbl, onto a hi-compression 340 short block, and found myself with a tire-fryer. Sure it ran out of steam early, but first gear was killer big fun, and second wasn't far behind. What more can a guy ask for; I mean the speed limit in town is about 35mph, sometimes 45. With 3.23s that's all first gear work!
Would I run the 318 cam today?
Well no; the 360 was born with an 8/1 Scr so a 318 cam is gonna be a bit mushy for me now; it ain't no hi-compression 340 short. I just guarantee you that installing a 318 cam into your 8/1 engine will be
more fun than what YOU now have. And people give used ones away for free. So all it costs you to find out are some gaskets.
The Wallace predicts, with the 318 cam in an 8/1 360 at 800ft, the pressure should be up at 136psi and the
VP to 128.. 128 compared to 100 is an increase of 28% performance below say 3300 in your combo. That would be 30 mph.
You can think of that 28% as similar to 28% more rear gear ratio so
1.28 x 3.23=4.13.... of course by 3300, it will be back to feeling like the 3.23s that she is. This is your bar-none cheapest fix. Even the stock 360 2bbl cam will pick up the pressure & V/P
but the best fix is to get the pressure up, and in your case probably to shelf that cam AND set the pressure up, together with your next cam. But only you can make the money-decision.
