340 4 speed vs 5.2 5 speed

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66jim said:
Maybe a little bit.
Click to expand...
Ok good cuz
not so many years ago I had a 223* cammed 367 cubic inch combo that made a fair bit more power than a factory 340, ran WOT on 87, and on one particular roadtrip made 32 mpg from point to point.The Scr on this combo was 10.95/1 and the cylinder pressure topped 180..This was my favorite engine combo.
For anyone who wants to copy this, here ya go;
In this combo I had the A833 overdrive box, and a GVod behind it, so she had 7 useable gears. This combo usually ran 3.55s, and the rpm was 65=1590..
But on this particular trip, I had installed my 3.23s, so 65 was ~1450 and, 80 was 1780, which is what traffic was doing. The final drive works out to; 3.23x.71x.78= 1.79
This combo usually ran a 750DP, but for this trip I took an old 1850 Holley 600 and leaned the crap out of it, until the engine really complained about it (no AFR gauge), and then backed up a bit.

But this was NOT my favorite trans combo, and not long afterward that OD-box came out, in favor of a Commando box.....again with the GVod which has remained ever since. With 3.55s, now, 65=2240.
And when that previous cam died, I replaced it with a bigger one, so it doesn't get the mileage it used to. That's OK tho cuz she ain't a DD anymore either.
The new cam makes her a real ripper. 93mph in the Eighth. By the Wallace calculator, 93mph should be 433hp@3467 pounds. What the Wallace calculator doesn't know is that I was splitting gears.
Normally, to hit 93, you might use 3.73s and Third gear for 93=6030, or 5.28s to hit in Fourth at 6100.But I ran 3.55s and hit it in Second-over at 6140..... splitting twice and just one pull on the stick.
I had no idea how fast the car was gonna go, so I just drove to the track with the regular street set-up. I dropped the exhaust, bolted on a pair of 325/50-15 BFG DRs, hoping for traction, (but it was not to be), and hit the start-line .
BTW; this gearing combo hits 60 mph at; 6380 with 3.55s/5800 with 3.23s; in First-over,no stick pulling at all. And she spins the 295/50-15s all the way. Just point,shoot, and hang the heck on!

The point is this; Why bother with the small stuff when a sharp 360 can cover all the bases, and costs about the same to do it.
Bases, what bases?
1) Hammer down at 32 mph (my favorite),
2) zero to 60mph (second favorite),
3) hiway fuel economy (with the 223*/110 HFT cam, or similar), and
4) a decent Trap speed.
My next cam will be a Solid FT and on a 106LSA (or less), so I will again be able to make some great hiway mpgs. The penalty is periodic lash adjustments;no biggie.
 
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