what size block do I have?

[Michael Martin]

I recently purchased another bas boat(94' 20ft Astro) with a 87(?) 135 Merc. It is a v-6. What block is it? I would like to tear into & find the goodies to make it into a 200 if possible. What would it take?

Mike Martin

[WillyT]

I believe that all "pre-Optimax" 135 V-6s were the 122 cubic inch block. The highest horsepower stock engine from Mercury with that block was a 175 (and that was crankshaft rated, not prop shaft, back in 1976-77). The first stock 200 Merc engine was the 2.4 liter (about 142 cubic inches) and then Merc upped that to 2.5 liters (about 153 cubic inches). The current Merc Hi-Perf SST120/S2000 engine is also based on the 122 cubic inch engine, and the catalog for that engine says "180 h.p.". Good engine. Just limited compared to other V-6s by being so small in displacement.

[jimmyb]

2.0L

you really cant upgrade this to 200, as willyt said

[Michael Martin]

What would it take even for a 150-175?
Front half, carbs, tuner?
Just need that little extra.....


Mike

[RocketMan]

The best combination I have ever seen for the 2.0 L Merc in high performance/pleasure use is the XR-2. This is not to be confused with the old XR-2 Bass Boat motor. The motor I'm refering to is basically a European offshore race motor that Merc sold from about 1995 to 2000. Somewhere in the last few years they made it available in the U.S. In non-race applications, it got a 1 year warranty, just like the other high perf. pleasure motors. It is not available in the 2001 model year in the U.S.

The XR-2 "Race" as it was called, was rated at 200 HP at 7000 RPM. It uses carbs, light flywheel, 16 amp charging system, one piece exhaust plate (plate and tuner is identical to the 2.4 EFI type). The intake is a 5 petal horizontal with plastic reeds. I believe the intake is cross drilled. The motor calls for 92 Octane leaded or unleaded fuel. I seem to remember "purple" 26cc heads on the ones I "touched". Exactly what the porting differences are between the 135 and XR-2 is a ???

I sold one to a buddy who put it on his 17' C'mate. Heavy boat, rigged heavy with a bow tank and a very "large" driver. The boat runs mid to high 70's for sure. Personal experience says these are great running motors that are virtually indestructable! HP is comparable to 2.4/200 stockers, but like the other guys said, the small cubes limits low end torque.

If you want to stay with the 2 liter block, make your 135 look just like an XR-2. See your local Merc dealer for specifics. Cross check the microfiche and buy everthing that is different!

OR DO IT THE EASY WAY AND >>>

Buy a bare XR-2 block P/N 884-9765T10 or a Longblock Assy. P/N 61-816719T21. Add the right electrics, carbs, intake, flywheel and exhaust plate/tuner and you're all set.

EVEN EASIER >>> Last week Coty Marine (732) 293-1000 had a complete drop on PH assy. for sale.

Have fun!

Paul