1988? Wellcraft 170 classic motor swap to 5.7 from 3.0

[Rmckinney]

I have a 88? Wellcraft 170 classic with a bad 3.0l. Got a good deal on a 5.7 that I'm wanting to put in it ( outdrive has been rebuilt to take the power increase..... So I'm told) my problem now is the motor mount locations. 3.0 mounts at front and the mounts on the 5.7 are on the sides of the motor.... Do they make any sort of kit to put in the boat or am I stuck trying to fab something myself. ( boat was free paid very little for the motor, so I'm not looking to spend a whole lot getting this thing running) thanks for any input and ideas

 

[Rmckinney]

Re: 1988? Wellcraft 170 classic motor swap to 5.7 from 3.0

Also, are the mounting brackets for the 5.7 universal or do they vary in size and height in different boats? I'm asking because I can get the rails out of another boat but it is larger than mine.

 

[Bondo]

Re: 1988? Wellcraft 170 classic motor swap to 5.7 from 3.0

or am I stuck trying to fab something myself.

Ayuh,... You'll need to fab up some new wooden mounting blocks....
Hang the motor "In-place", with an alignment bar aligning the motor, 'n measure from there...

You'll also need to change the gear ratio of the drive, from 1.98:1 to 1.50:1...

 

[Rmckinney]

Re: 1988? Wellcraft 170 classic motor swap to 5.7 from 3.0

Thanks for the info.... I'm new to the inboard outdrive thing.... What's the reason for the gear ratio change?

 

[nola mike]

Re: 1988? Wellcraft 170 classic motor swap to 5.7 from 3.0

To handle the increased power of the v-8. Otherwise you'll be spinning 6k rpms at WOT...

 

[Rmckinney]

Re: 1988? Wellcraft 170 classic motor swap to 5.7 from 3.0

Makes sense.... Thanks for all the info