omc to 8.1

[hefty67]

does anyone know what parts i will need to adapt a 8.1 (496) to a omc outdrive the boat had a 460 king cobra

 

[rodbolt]

Re: omc to 8.1

wow<br /> your going the hard way. I have done the conversion from 460 to 454. its not hard.<br /> you will need the correct shaft coupler and bell housing. I cant remember how the exhaust pipes fit but I dont think there were any issues.<br /> if you use the volvo 8.1 its easier. also if you use the existing Y pipes there is an exhaust balancer kit that MUST be installed if using an 8.1 or 8.2. if you dont you will find one day when you shut the engine off it will fill 2 cyls with water.<br /> but most of it was a straight fwd repower.

 

[hefty67]

Re: omc to 8.1

thanks, do you know of a good parts supplier

 

[rodbolt]

Re: omc to 8.1

not really. but do try to use a volvo dealer. that way you will have a working relationship with them. Thats a lot of iron <br /> and the 8.1 uses the standard chevrolet cobra bell housing. in fact the last 8.1 we recieved had the bell housing/coupler already on the back. it will also come with a y pipe but I cant remember if the mounting holes are the same as the cobra mounting holes. but I think the shaftcoupler is the correct one for the cobra.

 

[DJ]

Re: omc to 8.1

What's the matter with the 460? There are still hundreds of thousands of them still around. Including new.

 

[Don S]

Re: omc to 8.1

You might want to reconsider and replace the complete setup. Drive, transom shield and engine. The Cobra drive you have is going to be very borderline on accepting the power of the 8.1, you also have to figure out how to set up a shift interrupt to use the dog clutch type drive.<br />I've also found the gear sets for the King Cobra drives are almost non existant, same with complete drives.

 

[rodbolt]

Re: omc to 8.1

I agree with DonS. for a few coins more you can have a new package. <br /> DonS<br /> I have seen some bayliner 28's with 460 and king cobra labels that are actually clutch dog cobras. I know of 2 in my area cause I rebuilt both drives once before.<br /> if he tries to run an 8.1 in front of a clucth dog cobra failure will be imminent.<br /> like I said. its a helluva piece of iron. on a 28 Carolina classic with flybridge and curtains with DP-Edrives. a pair of 8.1's will push it at 51MPH at 5000 rpm. the guy held it that way for about 35 min then throttled back to a cruise of 4200 at about 38 MPH. was a wild water test .

 

[Don S]

Re: omc to 8.1

Instead of rebuilding the Cobra drives on those 460's, here's what I do with 'em.<br /><br />

<br /><br />

 

[rodbolt]

Re: omc to 8.1

yep<br /> the only way to fly

 

[hefty67]

Re: omc to 8.1

thanks for the info i think i will do the volvo complete package ..

 

[olbuddyjack]

Re: omc to 8.1

Huh! Will that work with 5.7 Cobra?

 

[rodbolt]

Re: omc to 8.1

sure