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re powering 1996 787 challanger with a 4 stroke

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Paul 1996

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I can get my hands on a 1996 787 challanger with a dead motor, and am looking at a bit of a repower project

Has any one heard of or seen a 1996 787 repowered by a 4 stroke, in particular a car engine? Ive been told of here in new zealand daihatsu charade 3cyl turbo diesel engines in small boats ( 45hp @ 4800rpm, 85nm of torque @ 2300rpm ), but would be really hard to get a decent pitch prop to give a decent crusing speed. The 993cc 3 cyl twin cam turbo makes about 180hp mildly modded ( I had one as a race car ), so possibly an option i would look at.

Ive looked at a couple of 1200-1300cc late model car engines ( toyota, suzuki etc ) not interested in bike engines ( way too expensive and not much low down grunt ). Even an 1800cc subaru boxer motor would fit really nice. Ive been told the 787 challangers run the small 140mm jet unit, but that the 155mm later units can bolt up without to many hastles? Are the 787 Gtx and the 951 Gtx same hull and different running gear. Ive looked at buying a 951 xp and swapping all the gear, but that would be to easy,
 
Don't try to re-invent the wheel. If you want to put a Diesel in the boat... do it... but the pump was designed to be run at 7000 RPM's. The diesel has massive torque... so, build a bearing block to support the drive shaft... and run a 2:1 ratio toothed belt. (double the drive shaft speed)


OR..... see if you can find a 13B Mazda engine. It can run at 7000 all day long.
 
a bare 4 tec in nz is mega expensive, and to buy a complete ski and wreck it for the motor would be even more expensive.

My main concern is can I bolt a bigger pump into the hull without cutting and reglassing the intake scoop. Making an smooth transition expansion adaptor and having the unit sitting further back is my current thinking.
 
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