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krustyballer16

Cummins B3.3 Powered Mj Build!

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Roger that. 

 

I have an idea that might be very worthwhile. Before final assembly, could you make templates of your adapters? Measurements of all dimensions (diameters and hole placements etc) would be easy to transfer to a CAD program. Such might come in very handy sometime in the future...

 

Use of aluminum for the flywheel adapter seems potentially sketchy, I dunno. I guess maybe it is perfectly suitable for a low RPM application, less so for high rpm, but something about that bothers me. First and second order vibrations inherent in the I-4 engine make me wonder about durability issues resulting from metal fatigue, too. I know your application has been done before, so that is comforting, but how would you (or even the fabricator) find out about long-term failure of the same custom parts, outside of your own experience?

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Roger that. 

 

I have an idea that might be very worthwhile. Before final assembly, could you make templates of your adapters? Measurements of all dimensions (diameters and hole placements etc) would be easy to transfer to a CAD program. Such might come in very handy sometime in the future...

 

Use of aluminum for the flywheel adapter seems potentially sketchy, I dunno. I guess maybe it is perfectly suitable for a low RPM application, less so for high rpm, but something about that bothers me. First and second order vibrations inherent in the I-4 engine make me wonder about durability issues resulting from metal fatigue, too. I know your application has been done before, so that is comforting, but how would you (or even the fabricator) find out about long-term failure of the same custom parts, outside of your own experience?

I will try to do some measuring today on it. And I'll price aluminum and labor at the fab shop I work at and see how much I could get more made for. (in guessing not cheaper than I paid, but I'll ask)

 

And I don't know about the aluminum flywheel adapter. I'm guessing it shouldn't be a problem since it's been done before but who knows. Ill know soon enough. I think it should be fine.

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Home improvement projects that HAD to get done and brother in laws motor in his Comanche took a dump so that's where our time has been. Hopefully by the end of the month we'll be on it again. maybe, were picking up a J10 as soon as the snow clears soo....ya... But I'm getting anxious.

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'79 with a 360 that runs pretty decent. It's got some rust and holes and dents but nothing major. Interior is really good for the year. Comes with another set of front fenders and header panel. Has stock roll bar and stock am/fm/cb combo with original Mic. 67,*** original miles. and owners manuals. $900.

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I may have missed it but is your mj stock height or do you have a lift,if so what size. Great work by the way i can't wait to see this beast road ready.

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It is stock height now but when we did a quick test fit on the 2wd truck we were very close to the axle (we think) so I got a 4.5" rustys lift. All our other jeeps have 3 inch lifts so I figured I'd go bigger to be different.

 

I got most of the engine bay degreased and most of the underside of the cab and the tranny tunnel stripped and ready for undercoating.

 

Won't have much time to work on it during week for a while cuz of work so we've just got weekends.

 

Gonna buy everything I need to replace everything in the front axle this week so it's ready to do when we throw the lift on

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I don't have any way to weigh it but from what I've read, the Cummins weighs about 140-180 pounds more. Not too bad. The Cummins being shorter is easier to handle and move around though I think.

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I was thinking from the point that you may want to get front springs to offset the extra weight.

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I've been hunting for 3.3 conversions! Subbed.

If you have any questions I'll try to answer them the best I can from our experiences with this...

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how much firewall choppin did you have to do?

Ive got a buddy of mine in west tn who can get me the 4bt and i need to figure out how easly i can make it fit an 86

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