AJ's Opinion; my super-fun, 360/A-833/3.55 street-combo

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>>Now, some History!
In the beginning, 1997, I didn't know any of this. There were no V/P calculators nor even Dcr calculators. I had seen guys throw big cams into low-compression engines for years with always the same sluggish bottom-end results. I had even done it myself. This time it would be different.
So I started pouring over magazine articles looking for hi-torque combos and trying to figure out how they did it, and still run pumpgas.. Finally it dawned on me that the engine doesn't make compression from Scr. It cannot start to build compression until the valves are closed; DUH. So then I unchained myself from Scr. I was a pretty good math student and I still remembered a few trigonometry formulas, so I attacked the magazine articles in a new way. And that pointed to a new way of figuring out compression ratios that I would later, after the world got the internet, find out was called Dcr or Dynamic Cylinder Compression. Boy I'll tell you, I wore out about a half a dozen slide-rules before I figured out that the 292/292/108 cam I wanted to run, would need more than 11.3Scr to just not be a total slug off the line. Of course no speed shop agreed with that, and even the machine shop I was working at said; no way, 9.5Scr was the limit. And, worse yet, I had no way to know what 11.3 would do at WOT after 3600rpm. So I took a chance thinking I might need to add a water-injection kit to it at some time in the future.
So I said to my boss; ok, here's my block; this is what I want, and I'll put her together myself so your shop will not have it's name dragged thru the mud when it fails, as you say it will.
Of course the Dcr on that 11.3 combo was still only 8.4, so maybe I couldda run iron heads! But I was planning ahead. I knew the 292 would probably be too big, (and it was.... for me), But I had set it up to run the .028 gasket so I had plenty of room to move around in,(and I did).
So now, after driving it for several months, I knew where the upper limit was, as to what was too big; so I yanked it out. This 292/292/108 cam had a C/E of 212, and this number was just too small for me.
But where was the lower limit?
I didn't know, but I now knew that 170psi was easily doable on 87E10. So I knew I could pump it up by jumping down 2 sizes at least, and after talking to some bigshot at Hughes, lol, and not getting anywhere with him, I ordered a cam THREE sizes smaller with a C/E of 227; oh Lordy I was gonna either have bottom-end torque up the ying-yang, or it was gonna blow up!.
So I slid that 270/276/110 into that 11.3Scr engine at 106 installed centerline........ and you guessed it she was a torque monster. In at 106 the extraction came to 108 and that made really good fuel mileage. I was a happy guy. The pressure came to over 190psi with a VP of 169. ridiculous tire-frying was the norm.
At the end of the season in year 2000, at it's first scheduled freshening, I discovered the .028 gasket was migrating into the valley. So after a little research the .039 FelPros were ordered up. But I really liked the high pressure so I had the block decked to zero. The new Q dropped from .040 to .039, lol no big deal. Since this 227 C/E cam was making ridiculous amounts of tire melting torque, I decided to try and get some top-end back that I had had with the 292/ 212C/E cam. So I installed it straight up at 110*.
So now the new numbers were 10.8Scr/174psi and a VP of 148, a much more sane number. This changed the extraction to 112* and I was soon chasing mpgs into the 30s. Think about that. To be fair, I was now running an A833od and a GVod behind that, so with 27s that was 65=1600/ 85=2100.. She topped out at 32MpgUS.
And with the cam installed at 110, I picked up some power over the nose and extended the powerband a few hundred rpm; altogether a triple win for me. If I was happy last summer, I was ecstatic this summer. I left it that way until the cam, in 2004, started dropping lobes right after an oil change. You guessed it, a victim of the zinc claw-back. Boy I'm still miffed.
The take away here was that a C/E of 227 makes a daymn fine cam.
Ok so back to building a streeter.
Ok but wait!, lol. When that cam fell into the pan I got to thinking..... if a CE of 212 was terrible, and a CE of 227 has fantastic bottom-end ; then how about something up the middle? And so I called up Hughes and ordered a cam with a CE of 219, I mean that's how the off-the-shelfer came. And I mean, 219 is exactly up the middle between 227 and 212.
BAAAAAD mistake. I lost bottom end big time. And the top did not seem any better than the previous cam. So you guessed it, to find out what was doing it I took the engine down and decked it some more to get the Dcr back up. By this time I was real comfortable with the pressure.
The new Q is .032, and Scr is back up to 10.95 with a Dcr of 8.6, pressure of 175, and a VP of 148. So that should do it right? Well yeah the beast is now back in action but in at 108, the extraction is down to 105 and gone forever is the 32mpgs. So I got rid of that A833od, cuz 65=1600 was not gonna work for this combo anyway, and which I never liked, and I kept blowing them up all the time.
The take away for me was that the change from 227C/E to 219C/E was just too big for me.
Ima thinking that next time, I will try ~224. Hyup I think I can work with that.
Ok so now you know all about my escapades with C/E and why I think this is so important. So