Okay, you guys are trying to say a 2.73 gear will get you off the line quiker than a 5.38 gear will???????????????????. You might as well say a a cut impeller will give you more top end than a c cut impeller will.
Okay, you guys are trying to say a 2.73 gear will get you off the line quiker than a 5.38 gear will???????????????????. You might as well say a a cut impeller will give you more top end than a c cut impeller will.
No, what I'm saying is that with a 3.73 ratio, more torque would be required to get your RPMs up than would be with a 5.38...just like more torque would be required to get your RPMs up with an A impeller than with a C impeller.
Okay, you guys are trying to say a 2.73 gear will get you off the line quiker than a 5.38 gear will???????????????????. You might as well say a a cut impeller will give you more top end than a c cut impeller will.
Assume you have a high gear only car a one speed. A 2.73 gear will accelerate slower and will reguire more HP to run to 6,000 rpm. If your engine had the power to tun it to 6k you would be hauling a$$. The problem is if you only have 550 HP you will never pull your 2.73 gear to 6k.
Replace those gears with 4.88's. The 4.88's will accelerate the car faster off the line and rev out faster. The problem here is the gears will over rev the engine if your 550HP engine is set up to turn 6,000 rpm's. You'll run out of gear before you get down the 1,320. And if you go out on the Freeway you will be cruising at 65 mph at 4,200 rpm's.
Just my .02
Sleeper CP
Big Inch Ford Lover
Not going to get in a pissing match here. Hey speedy 21ft cruiser needs bottom end to get going. {short gear} a- cut will get better bight on the bottom end with the torque specs you showed. c cut will get better mph thru the lights {c-cut } period. Call jack at MPD and ask him, he is in costa mesa ca. I'm out.
OK, I see where you guys are going
In my duster, with the 8000 rpm 440, I put in 4:30's to go fast in the quarter mile. Vast improvement over the 3.91's I had in there.
Now I have a quick reving 528 with the 4:30's - Now it doesn't matter 1,2,3rd gear on take off - it accelerates the same. This is because the torque is overwhelming. To go faster in the 1/4 mile, I needed to put in a 3.23 gearset to get the top end back, as the 4.30's limited the top speed and I'd run out of gear on the 1/4 mile. Basically I needed to use the slow stock parts to go faster.
Thinking about it, the impellor is the stall, the gear AND the tire.
A "C" has a nice "stall" (let's the motor wrap quick) medium "gear", but no "tire". So in a heavier hull, it won't push enough to get the boat to move initally. OK with a smaller motor that needs the "stall or gear" more than it needs the "tire" but not in a heavier boat. The "tire" becomes less imprtant the faster you go (easier to do a burnout at 5 than at 100).
An "A" has no "stall", no "gear", but lots of "tire", so everything it gets, it moves. In a motor that has torque, that is the same as when I went to the 528.
I think I understand. somewhat. :messedup: :2purples:
big boat that pulls skiers = big impeller.
I agree......
OK, I see where you guys are going
In my duster, with the 8000 rpm 440, I put in 4:30's to go fast in the quarter mile. Vast improvement over the 3.91's I had in there.
Now I have a quick reving 528 with the 4:30's - Now it doesn't matter 1,2,3rd gear on take off - it accelerates the same. This is because the torque is overwhelming. To go faster in the 1/4 mile, I needed to put in a 3.23 gearset to get the top end back, as the 4.30's limited the top speed and I'd run out of gear on the 1/4 mile. Basically I needed to use the slow stock parts to go faster.
Thinking about it, the impellor is the stall, the gear AND the tire.
A "C" has a nice "stall" (let's the motor wrap quick) medium "gear", but no "tire". So in a heavier hull, it won't push enough to get the boat to move initally. OK with a smaller motor that needs the "stall or gear" more than it needs the "tire" but not in a heavier boat. The "tire" becomes less imprtant the faster you go (easier to do a burnout at 5 than at 100).
An "A" has no "stall", no "gear", but lots of "tire", so everything it gets, it moves. In a motor that has torque, that is the same as when I went to the 528.
I think I understand. somewhat. :messedup: :2purples:
You sound like a true Mopar or no Car dude.... Nice
I think I understand. somewhat. :messedup: :2purples:
Close enough. Oldguys example would work better if your boat was an 18' racer although he is 180 out on his example.
As Yellowboat said" Big Boat to pull skier, need big impeller"
Start with an A or A/B you don't have a little race boat. You need to move volumes of water to move your big boat.
Sleeper CP
Big Inch Ford Lover
I would start with a AA and cut it down to a 1.5A if needed. I would not go smaller then an A.
I would much rather go a little slower and save the motor, then go a little faster and blow it up.
That's what i've been trying to tell you and maybe misunderstood but bottom line is you are on the right track. good luck M
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