[drailed]

This is regarding my friends boat. It has a 5.7 chevy motor in it and i know its an 1989. He was thinking of converting it from points to an HEI. I was curious as to why they even use points in something that new and if an HEI out of a car would swap out or if it spins the opposite direction. I would also imagine the advance curve would be a bit different. Is it worth doing the swap? Thanks

[78 GHOST]

I wouldn't want to use a automotive dist. as the marine applications are probably specially designed to prevent errant sparks from igniting any fuel vapors. You might be able to use a Pertronix setup to convert your existing dist. to pointless ignition.

[sleepy]

My dads cruiser had twin 5.7s in it. They had HEI set ups. Has he had this boat sense it was new? maybe the first owner switched it to points? cheaper than HEI to repair. On opposite rotation motors the cam and dist turn the same direction as normal only the crank turns the other way. They do this by using two gears instead of a timing chain. and they mount the starter backwards. so it spins the crank the opposite direction.

[george kujanski]

My brother's previous '87 Sea RAy had twin 4.3L with Prestolite point distributors. We converted to Pertornix.

My boat is a '90 5.0L and has the Merc Thunderbolt ignition. A HEI may not be directly applicable because, yes, the ignition, starter, alternator, and anything that can make electrical sparks needs to get YSB (yacht safety bureau) approval. I don't know why it took boat manufacturers that long to implement electronic ignition, tho, since cars were using it since '76 or so.

George

[drailed]

Thanks for the responses. His parents bought the boat new in 89 with the points in it. and he bought it last year. That would make alot of sense about the special marine application regarding sparks and fuel vapors. Ill tell him to look into a petronix conversion for it.

[TAftw]

I'm just wondering, when you say 5.7L Chevy, do you mean an actual Chevy engine, or do you mean a 5.7L block, as in a Mercruiser engine?

[Transam Stripper]

A standard HEI from any Chevy will work fine. I have done the swap in a friends '89 something boat. All that marine talk is great but most of the time it's over kill for most boaters. I had a Mercruiser 470 4 cylinder. The starter went out, the marine replacement was $400.00 10 years ago. So I went up to a starter rebuilder laid the starter down and the guy said what kind of Jeep you working on. He brought out a Jeep starter that was identical. $45.00 later I had a starter. It lasted 10 years just fine. Also I needed a silonoid for it, marine was outragous. Went to Napa bought a silonoid for a '78 Granada, worked fine no problems. Sold the boat with it on.

[78 GHOST]

Maybe they did work OK functionally, the problem is that in some applications the proper shielding is kinda hard to detect.. the differences can be rather small.

The problem is that in this application the results are kinda pass/fail. I've seen enough boats burned to the waterline to be concerned about vapors and control of ignition sources.

Light aircraft have similar issues, but for different reasons. Many parts are identical to those available over the parts counter at NAPA, etc. Voltage regulators immediately come to mind. A typical GA voltage regulator for a Cessna 180 is exactly the same as a typical early GM regulator, except the PMA stamp adds about $100 to the price.

[1967Clone]

Originally Posted by TAftw

I'm just wondering, when you say 5.7L Chevy, do you mean an actual Chevy engine, or do you mean a 5.7L block, as in a Mercruiser engine?

Same thing pretty much.

[drailed]

This looks like it may be the kit he needs

http://cgi.ebay.com/ebaymotors/Pertr...2em118Q2el1247