Thread: 88 120v4

Originally Posted by jug head

Hey all I have a 88 120v4 found some 93 140v4 heads and intake manifold will the 93 heads and manifold fit my 88 120v4. Trying to get more power tks

here is a site that might help you out !!! it has some good info !!!

Johnson and Evinrude Outboard Motor Parts -Mastertech Marine-

Careful with changing the heads even if they will fit. Some of those older 140's were juiced up 135 with high compression heads. Also to really get the added horse power they can bring you need to change out the exhaust tuner from the 140.

Mr Cray so I wood need intake. Heads. And exhaust tuner .and would a say 93 140v work on a 88 120v4 or do I need to look for same year as my 88 120. I found some 93 140v4 heads and intake with reeds for 100

Originally Posted by jug head

Mr Cray so I wood need intake. Heads. And exhaust tuner .and would a say 93 140v work on a 88 120v4 or do I need to look for same year as my 88 120. I found some 93 140v4 heads and intake with reeds for 100

did you look at that site I sent in my post ??? I believe for the year motor you got that the parts would work in these year range 1988-1991 !!! the 93 would be different IMO !!!

Originally Posted by jug head

Mr Cray so I wood need intake. Heads. And exhaust tuner .and would a say 93 140v work on a 88 120v4 or do I need to look for same year as my 88 120. I found some 93 140v4 heads and intake with reeds for 100

I didn't do a bunch of research but like Stormwalker says, I don't think those would mate up to your block. But yes if you find some 140 heads from an older motor that match you will need to replace intake and tuner to get full potential out of the head swap. That is not to say if you have a bad head that you couldn't use them but you would need to replace both and know if they kept the compression at the same pressure. Some of the 140's had higher compression heads and require higher octane gas to not burn a piston.

Cray, does that work with most outboards? Is it cost effective to someone that doesn't have experience working on outboard motors? It would be novel to have a little more get-up-and-go for the boat.


Sent from my iPhone using Tapatalk

Originally Posted by Adcarson79

Cray, does that work with most outboards? Is it cost effective to someone that doesn't have experience working on outboard motors? It would be novel to have a little more get-up-and-go for the boat.


Sent from my iPhone using Tapatalk

I honestly don't know much on other motors. My experience has only been with older 80's model OMC motors. I found out most of this by hot riding a 81 115 Johnson with 140 parts from a 84 model. I know some parts can be inter changed on certain XR series merc motors like the 150,175 and 200. On them and most motor hop ups to really get them going it takes machine work to lower or raise the intake/exhaust ports in the block. I personally don't feel it's really cost effective to spend a bunch of money on a outboard for the small amount of gain in performance you get on the average fishing boat. If you had access to really cheap or free parts and are a mechanic yes you can gain some performance by being able to swing a bigger prop and still retain your hole shot. In that you might gain 2-5 mph.

I'm thinking the 120 is a cross flow engine and the 140 is loop charged. If that's the case, proceed with caution on doing part swaps.