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Discussion Starter #1
For a 93 4bd2tc, need everything to convert from automatic. I also have a Jatco jr403e auto for sale or trade.:)
 

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The model you're after is probably an MSA series. Take a look through the sticky posts at the top of the page, one of them has gear ratios of the common MSA boxes.

Some are overdrive, some are not. That will help you identify any you may come across.
 

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Discussion Starter #3
Transmission Ratios

I'm putting it in a Chevy 3500hd which had a 6.5 turbo Diesel. I believe the engine redlined at 3250 rpms?? and horsepower and torque were a little more than the Isuzu @ 155hp? 275ft torque. Truck has a GVW of 15,000lbs weights about 8500 empty and will have about 3000lbs on it most of the time. So will be 11500 lbs most the time, I will occassionally tow a heavy dump trailer, and I live 1500 ft above sea level. There are some small hills around here, but most would be 60-70 mph freeway. Any recommendations would be greatly appreciated :idea:
 

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I think you will be happier with a 6 cylinder, be it a cummins or an Isuzu.I have both, and while the 4 is fine for a flatbed with a couple of tons of material, the 6 is far better for towing a heavy load.Another bonus with the 6 is that overdrive 6 speeds for the 6 are available here, while the o.d for 4 is not (at least not readily) I think fuel mileage with an overworked 4 would be worse than the 6 as well. My two cents...
 

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I hope my friend Bill Hartlieb contacted you. We have a good shape 5 speed in our shop from a conversion that he is looking to sell. Thanks, Andre
 

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Discussion Starter #7
trans

Thanks Coog , but I already have the engine. Dougal I don't know what the rear end ratio is but I will find out, the rims are 19.5" low profile type truck tires. I will measure. Seems to me if the Chevy reved to 3250 a little more than what the Isuzu rev's (3000 rpm 92% of chevy ) and the chevy trans (4l85e) had an overdrive, then I will need an overdrive also.
 

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My 4BD1T is governed to 3600rpm, 3000rpm is for the industrial stationary engines.
Adjusting the rev limit is simply a screw on the top of the fuel pump.

I know they'll rev out to about 4000, but they don't sound nice doing it. It's not really an option for cruising rpm.

Is it possible to set it up for an overdrive for cruising unloaded to get the revs and fuel usage down, use the direct drive next gear down for heavier stuff.
 

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Discussion Starter #9
Is it possible to set it up for an overdrive for cruising unloaded to get the revs and fuel usage down, use the direct drive next gear down for heavier stuff.[/QUOTE]
That would be great! Glad to hear 4bd rev's higher than the Chevy did.I will measure tires and find the chevy's rear end gear ratio tommorow.
 

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Discussion Starter #10
I got the info for gearing

Tires are 31" tall 100" circumference , Rear End ratio is 4.63. Will a 1 to 1 final drive work or do I need an overdrive?
 

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Tires are 31" tall 100" circumference , Rear End ratio is 4.63. Will a 1 to 1 final drive work or do I need an overdrive?
I figure 100km/h (63mph) will give you about 3100rpm with 1:1 gearing.
I'd be much happier with an overdrive to save fuel and noise, but the engine will handle that.
 
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