Performance Boats Forum banner

1 - 9 of 9 Posts

·
BTC cardcarrying member
Joined
·
1,075 Posts
Discussion Starter #1
I have found myself with the opportunity to buy this motor that hasnt run in probably 10 years.It has about 15-20 hrs on it.It is in a Sterling Jetboat that Im looking at.My question is,Is there any thing I can do to it to run PUMP GAS? If so,at the same time what do I do to make more H.P.?My plan is to run it in my Jetboat.Hydraulic Roller,or Solid Roller.Can I inslall a Whole bunch of overlap to drop compression or do I add thicker head gaskets to drop compression? Really wanna buy this engine...Thoughts???
 

·
Some guy
Joined
·
3,608 Posts
I have found myself with the opportunity to buy this motor that hasnt run in probably 10 years.It has about 15-20 hrs on it.It is in a Sterling Jetboat that Im looking at.My question is,Is there any thing I can do to it to run PUMP GAS? If so,at the same time what do I do to make more H.P.?My plan is to run it in my Jetboat.Hydraulic Roller,or Solid Roller.Can I inslall a Whole bunch of overlap to drop compression or do I add thicker head gaskets to drop compression? Really wanna buy this engine...Thoughts???

It's possible that it is one of the "marine" LS 6 engines that GM produced. They were 8.8-1 compression. When I worked for Gale Banks, we used to buy those 50 units at a time on pallet racks.
 

·
BTC cardcarrying member
Joined
·
1,075 Posts
Discussion Starter #3
It's possible that it is one of the "marine" LS 6 engines that GM produced. They were 8.8-1 compression. When I worked for Gale Banks, we used to buy those 50 units at a time on pallet racks.
So if I pull the heads off ,the pistons would be flat tops? Is this correct?
 

·
Strap on the JATO
Joined
·
305 Posts
sunkisst, get the #'s off the head's. You might or
might not have high compression. When you get
the heads check mortec.com or just post the #'s
here, you'll get your answer.:D
 

·
BTC cardcarrying member
Joined
·
1,075 Posts
Discussion Starter #6
sunkisst, get the #'s off the head's. You might or
might not have high compression. When you get
the heads check mortec.com or just post the #'s
here, you'll get your answer.:D
Gonna look at it again tomorrow or Thursday...CANT WAIT!!!!
 

·
E-7 Sheepdog (ret)
Joined
·
6,834 Posts
Anything 15 years old is early 90's and I seriously doubt any closed chambers were used by GM then. Flat-tops in most of the open chambered GM heads would yield only arround 8.2:1 (on a good day). You should have a small dome of some sort.
 

·
Some guy
Joined
·
3,608 Posts
So if I pull the heads off ,the pistons would be flat tops? Is this correct?
The 8.8-1 was achieved with a small dome, roughly 1/8" and the 990 open chamber heads. You should be able to get the block casting number and mfr date off the rear of the block above where the bellhousing would mount. The head casting numbers are visible by removing the valve covers.

Feel free to email me if you would like more information

[email protected]
 
1 - 9 of 9 Posts
Top