Here's a question I think the answer is a no. Can a car with the 292 cam have A/C? Probably due to the nature of the beast it will not do to well especially in hot climate. I wonder if using the sanden style compressor will be more forgiving?
I think that would sorta depend on the combination of ;cylinder pressure, idle-speed ,stall,and tune.
But I think with iron heads, you're probably right.
With iron heads and pumpgas, you are sorta limited to 160psi with open chamber heads and about 165 with a tightQ, both at sealevel. With the cam in at 104, that cam is sadly lacking in low-rpm power. Tic-over at 650 in gear ,is a tuff tune, and an A/C compressor would probably drag it down to a stall. However, you could just wire in a
Hobbs switch to the clutch and disallow it's operation below a certain manifold vacuum.
Advanced to in at 100 that cam perks up a bit,at low rpm; but if you have to do that, then you might as well just put the 284 in instead, cuz the overlap period is so far out of sync, that the 292 is gonna act like a 284 anyway. AND, the 292 is gonna be horrible on fuel compared to the 284.
>Picture this with the 292 in at 100:
the durations are; intake-compression-power -exhaust;
292-114-
98-292, and It has 76* of overlap but the installed centerline is splitting it as 46 to the intake and 30 to the exhaust. This is backwards and totally reduces the ability of the header to pull on the intake, AND pushes a bunch of EGR up into the intake.
> now picture the 284/292/108 in at 104. now we have;
284-114-
102-292, and it has 72* of overlap with the split now 38 to intake and 34 to exhaust. This is now 8* less EGR and 4* earlier pull on the intake charge. That's a win-win right there. But that is not the whole of it. Check out the 4* more power stroke. This is a little longer push on the power stroke, getting you a little better fuel economy.
Since the compression degrees is 114 in both cases, the cylinder pressure will be the same. What that 292 is giving you that the 284 is not, is an intake charge full of 8* more EGR, which ain't doing a lick of good.
That 292 is a high compression cam,and likes stroke, and does not do well below 160psi in a 3.315.
Here are some examples in a 340 at various compression ratios;
ICA--Scr--Dcr--Psi--VP
70*--9.8-7.45-146-109VP This is in at 104; the regular install,typical Scr
66*--9.8-7.69-152-118VP This is in at 100; Notice the large jump in VP
70*-10.5-7.96-
159-119VP Compression increased for open chamber heads
70*-10.8-8.18-165-123VP Compression increased for tight-Q
70*-12.0-9.06-188-140VP Compression increased for aluminum heads and tight-Q
Follow the VP, cuz that is the indicator of low-rpm performance up to about 3000/3600.
Here it is in my engine, a 367 Eddie headed ,wanna be racer.
70*-11.3-8.74-176-
143VP Notice less compression/more VP/plus 27 cubes. I was very disappointed with that VP in my combo.
VP is more important with a manual trans and lo-perf gears. This is because the rear tires are directly connected to the crank, without the help of the fluid-coupling or it's TM characteristics.
With an automatic, you can just throw more stall at it until you find you're happy place.
Read about VP here;
V/P Index Calculation
And of course, here is the 284/292/108 in at 104, for open-chambers;
66*-10.2-7.99-
160-124VP Compare this to the blue above; less Scr/ more VP
But before you get too excited about 124VP,lol
this is about what a 5.2Magnum makes, or an early 318LA. Seriously. Get you a big stall and big gears, and an overdrive, cuz that 292 doesn't come alive until about 4200 or 34mph with; iron heads, an optimized Scr,and a 904/4.10/29tire combo. Ok to be fair, it was sorta waking up at 3600 in my tightQ eddie headed combo. I just revved the crap out of it and dumped the clutch with my 9.44 starter gear,to break the tires loose; and then away I went.
