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Poor Man's Performance Increase for the M-715

Contributed By: Al Krason

This is Al Krason here in Denver, there is an alternative to the 230 Tornado,(that is blown) in the M-715 Kasier Jeep there is an inexpensive replacement for the 230.

**Please note that the 230 Tornado is not un-reliable, but is very underpowerd for the Kasier M-715 Jeep.


I did some looking to see what will fit the T-98 4 speed in the Kaiser, M-715 Jeep, while retaining the original T-98 4 speed. This is what I have found:(please take this for what it is worth to you as the most inexpensive upgrade of M-715 Kaiser). If a "PROPER UPGRADE IS DONE" the cost is indeed very high, going with the standard Novack $360, Advance Adapters, cost is about $500 for A/AD + $130 for eng mounts.

  • $800. Rebuilt 350 chevy
  • $630. A/AD
  • $ 75. Bellhousing used
  • $ 50. Clutch new
  • $ 25. Pilot bushing/bearing new
  • $ 30. Throw out bearing new
  • $ 75. Pressure plate
  • $ 75. Flywheel used
  • $250. Core for 350 chevy (no they will not take the 230 Tornado in exchange)

About $2000. for just the main hardwere and when you add the stuff below it will push you to about $3000. So you got a good truck with a 350 cu engine. Now I now that to install a DIESEL 6.2/6.5 GM is much more expensive the GM has the same bolt pattern as the 350 Chevy) so 6.2 is $3200.00, a long block rebuilt with injector pump, you still need a core, and all the stuff in the middle. About $4000 big bucks. So the question is what can be done to make it a "Good project with some reason of sanity"??

Please note that I did not include stuff like: Labor Cost, radiator, oils & fluids, filters, new starter, alternator, carb, distributor . stuff & wires plugs etc.etc...

The METHOD M-715 upgrade (take your time in developing the proper steps in conversion, remember it's all cost, Your's).

  • Use the AMC 360/401 engine,(they are very inexpensive In Junk Yards about $100. for a whole engine (U-Pull)in the Denver market, overhaul kit is $170 with all parts I.E. rings, bearings, gaskets,etc..)
  • You need to get the bellhousing, from the T-18 4 speed (it came on the following J-series Jeeps full size, with 8cyl 1971-1978 (tooth count S27-L17T & S27-L23T)). Stickout is the lenght of the shaft on the output of the 4 speed, just the shaft to the first step on the 4 speed) the length of the sitickout has to be 14 1/8" on the right T-18 4 speed. The T-98 4 speed has a stickout of 10 1/4" too short for the bellhousing that comes with the full size J-series trucks. The T-98 & T-18 are the same length and have same bolt pattern, the difference is the size of the input shaft diameter, T-98 has Diam. of 1 1/16" and the T-18 has the Diam. of 1 1/8". The T-98 has 17 splines & the T-18 has 17 & 23 splines-(71-72) 17 splines-(73-78) *I am only talking about the 14 1/8" stick- out 4 speed and years made.. If you can find a Jeep (fullsize) that has a 360 or a 401 with a 4 speed (T-18) it will drop in to the M-715, (the best method & cost effective, all from Junk yard $250.) in the following years 1971-1978. A T-98 can be used providing that a input center shaft is changed from 10 1/4" to 14 1/8" (a disassembly of T-98 is required).
  • (C) COSTS>>>>>>> $150. eng good runing (bellhousing & flywheel etc..) (Junk yard block).
    • $170. overhaul kit
    • $ 80. shaft for T-98
    • $ 50. clutch heavy duty
    • $ 30. throw-out bearing
    • $ 75. pressure plate
    • $ 40. eng. mounts

    This is much more sane $600. plus Labor & Stuff $1000... $1600.

    I will try to refine this further for better costs. Let me know if this list can be expanded more, to include better way of doing stuff... ADD, EXPAND, INPUT, SUGGEST, PLEASE !!!<<<<

    I hope this helps those owners that have the FSJ-Military types.

    Al Krason, Denver

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