whats faster 140 omc or 115 merc

[MJ POWERSPORTZ]

going to run my vector in formula-v class this next summer and im wondering if my 82 115 mrc inline would be faster than a 140 johnson, my thought is omc are easyer to work on but i just need to know what would be faster stock for stock and accelarate better also.. i know a 140 is a 115 in todays standards.. thanks in advance.. i have a guy that wants to trade me a 140 for my merc.

[Riverman]

What year 115?

[PARKER RABE]

Neither , put a 2.5 on it

[Riverman]

Max in Formula V is 100 CI.

[MJ POWERSPORTZ]

its a 82 merc inline 115 ADI ignition, the 140 is a 81

[Riverman]

The inline is 115 crankshaft horsepower, the xflow is 140 crankshaft horsepower. I'd say the Johnny is the choice. :)

The crossflow is very easy to work on too compared with the inline. I see a great deal of value in being able to remove the heads to have a look inside.

[Riverratt]

Wont the 81 140 be crankshaft hp also?

[Riverman]

Yep, I edited my post to clarify. Thanks Rat. :cheers:

[MJ POWERSPORTZ]

:iagree: i agree with you riverman, im tearing my boat apart next week core and such... should be fun...doing sringers and light foam coring. need to drop a ton of weight. riverman whodid your porting on your 140? think im going to have mine done and have the mid cut as well. you should call me so we can chat. 218-834-8213

[Superbender]

140 omc:thumbsup:

[Riverman]

I think you have to run stock porting if you run in the TCPBA, do you not?

[MJ POWERSPORTZ]

i just talked to my buddy he said yes i does have to stock now. it used to be full mod or stock but i guess it changed since i raced last. oh well cheaper that way. think ill still run 70 with the 140 on my vector? thats what im running with my inline

[MJ POWERSPORTZ]

Jeff do you do do drags? or just a lake boat? id like to do drags if i could find a place to do it with a V4

[samari]

Mj check out umpba.org for the drag racing. There is a new class this year for the 70 mph boats.

[Mr.Rude]

If you run the OMC, couldn't you run a Nitro gearcase from a 75 Stinger for the 1.86 gear ratio? You will have to lengthen the shaft somehow, but you will have the taller gearing and smaller surface area.

[MJ POWERSPORTZ]

dont think that works, driveshafts are totally differnt, i suppose anything can be done.

[Riverman]

I did the radar runs this year at Three Lakes, that was a gas. Also went to Lake Koshkonong but it was too rough for me to run but I had a total blast anyhow. Too old and sore to do roundy round!

[MJ POWERSPORTZ]

where is three lakes, how long of a run is it?

[Mark75H]

V-4's are kickin' butt at the 99ci Trihull races in Texas

[MJ POWERSPORTZ]

i might even get a comp ventura, its like feather lite. and you cant beat the releaved exhuast sound ov a V4

[Mr.Rude]

dont think that works, driveshafts are totally differnt, i suppose anything can be done.

if the shafts are different, you could use the top half of a v4 shaft tig welded together. Smaller gearcase, smaller prop, less rotating mass/drag and less surface area?

[Mark75H]

But hard to find props with enough pitch

[Mr.Rude]

I digress

[Riverman]

where is three lakes, how long of a run is it?Three Lakes WI up by Eagle River, it is a 1000' radar chute. Wife and I even enjoyed the drive as it is very different country than around here. Lots of Hydrostreams and others, big follow-the-leader tour of the chain the day before. We stopped for a break on a big long lake and it was rooster tails as far as you could see!

threelakesshootout.com (http://threelakesshootout.com)

[MJ POWERSPORTZ]

that sounds like fun:cheers::cheers:

[delawarerick]

If you are looking for a clean 140 built right Flabum on board here has a really clean one for a great price. I ran the newer 110 crossflow and built it and beat it for 7 yrs. Start and go went so hard the bearings turned blue. Rick