help getting started on building power train for 17' IMP

[Sporaticus]

well this would be my first post on this board so excuse any ignorance i treid to read the rules and remember them... I have a 1977 IMP v bottom, no motor or out drive, i do have a OCM transum and tilt, and was wondering what i could put in here, original motor was the little chevy four cyl. iron duke, Im new to the boating world so i dont know all my terminology just yet have been a mechanic for several years now i know my motors was advised by a freind that i could actualy cut out a peice of the back around the transum like a jig saw shape then cut another out of a donor boat that had the transum and out drive i wanted and fit it in, would this realy work? if so how big can i go? was hoping to put in a 305 merc if at all plausable, or what i want to realy do is throw in a 351m or 400m but i dont know if there are any transums thatll bolt up to those any response is appreciated even hateful ones for they give me somthing to laugh at

 

[MooseHootie]

Re: help getting started on building power train for 17' IMP

What was bolted to the transom before ? OMC stringer was a very big hole.

 

[Sporaticus]

Re: help getting started on building power train for 17' IMP

it is a large hole much large than most others ive seen, the motor was a 120 hp i think, an iron duke most people i know callem that, chevy 4 cyl. but its completely gone now so cant go out and look at it

 

[Sporaticus]

Re: help getting started on building power train for 17' IMP

help?^

 

[Doug Durako]

Re: help getting started on building power train for 17' IMP

The 77 IMP was a very well-built boat, but you might be faced with completely rebuilding your stern. Is there any rotten wood? If so, you must cut it all out. That hull should float a small block v-8, if it is not taking on water anywhere----look for spider webs in the fiberglass, or have a good body man who works a lot of fiberglass take a look.

 

[steve n carol]

Re: help getting started on building power train for 17' IMP

I also have an IMP about 19' long its a deep trihull....(got a good deal). It is a project and a "hole in the water....."but thats ok i am rich. haha. this one has a small block ford w/a mercruiser outdrive. SBC is a very popular way to go. lotsa parts around, new and used. OMC and mercrusier. Fuel is not cheap, you'll only get 1-3 MPG. for the power and size i'd go to the 4.3 GM V6. when this ford gives up the ghost i'll do the swap then. search the site for SBC and 4.3. It'll give you somthing to read while you save your $$$ for an outdrive....sl

 

[steve n carol]

Re: help getting started on building power train for 17' IMP

Hey, here is some more. there is alot of cracked block info at this site. I have been around boats most of my life. never, never, knew about that! where I live, while it does freeze, 2 nights out of the year, the freezing temps are there only for a few hours at a time. So, while youre looking for that powerplant in the cheese state, watch out for the cracked blocks and such...sl

 

[Sporaticus]

Re: help getting started on building power train for 17' IMP

ah thanks for the suggestions, ill look into that V6, is that the same one they put in the chevy trucks during the 90s?<br /><br />Ill be sure to keep my out for cracked blocks as well

 

[steve n carol]

Re: help getting started on building power train for 17' IMP

I am not sure, I had a 4.3 in a GMC van. Wow what a great unit! ' achris' swapped his and explained it to me quite well. There are several who post about this as well. seems that alot of the members at this site live up your way. you may find one who knows these things AND be able to set you up with what you need! <br />Search the 4.3 on the search engine. Read up on exhaust manifolds as well, these things were a $urprise to me. They only last about a decade, half that in salt water.