Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   Do It Yourself, Boating on a Budget (https://www.offshoreonly.com/forums/do-yourself-boating-budget-249/)
-   -   Marinizing GM 8100 (https://www.offshoreonly.com/forums/do-yourself-boating-budget/367750-marinizing-gm-8100-a.html)

gttdnbman 07-29-2020 03:15 PM

Marinizing GM 8100
 
Just thinking... ahead to a re-power in my boat. I see lots of threads and article's about LS swapping motors. I haven't seen any on taking a 8100 out of a Chevy truck and picking up an ECM, manifolds and intake off from ebay and having a fairly low cost 8.1? Am I missing something? Any thoughts just, seems like a stable platform and low cost way to get more power without going all out.

snapmorgan 07-29-2020 08:20 PM

More power than what? Half of the boats out there are running them

gttdnbman 07-30-2020 06:38 AM

More power than my 7.4 MPI (310hp)...

LakeHuronPower 07-30-2020 07:44 AM


Originally Posted by gttdnbman (Post 4750707)
More power than my 7.4 MPI (310hp)...

Not much more...8100 was rated at 340...and shares almost no parts with all other big blocks. Seems like a lot of work and money to gain nothing. You could swap a merc 496 if you found one, 425 hp.

Blueabyss 07-30-2020 08:41 AM

What size boat?

snapmorgan 07-30-2020 09:08 AM

A Merc 496 is a GM 8100

VoodooRob 07-30-2020 09:27 AM

496 Mag 375hp, 496 Mag H.O. 425hp Easy bolt in swap

SB 07-30-2020 09:40 AM

How much does the average 496 375hp complete used takeout generally go for ?

closed cooling, marine exhaust, marine accessories , ecu’s, wiring, fuel system may just end up being more value then starting with a motor out if a truck.

resurrected 07-30-2020 10:05 AM

Are the freeze plugs the same (as in galv vs brass)?

snapmorgan 07-30-2020 12:20 PM

The truck engines most likely have steel ones, but you are talking $10 worth of parts to install brass ones


All times are GMT -5. The time now is 09:16 PM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.