Thought I would share my 130 build with you guys since there is not a whole lot of information out there on these.
I have a stock powerhead 1994 Yamaha 130 on a 13' Biel tunnel hull that I believe is the fastest stock 4 cylinder pleasure at 84.5mph on GPS with no current helping.
Awhile back I had the water pressure gauge hose break under the cowling. The motor injected quite a bit of water and a subsequent compression test showed I was 20psi low on #4. Luckily I had just picked up a like new freshwater block with plans to eventually build a hotrod V4.
Hmmm....somethings missing on #4! Still made 105psi.
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I have been talking to all the usual suspects about doing the porting, balancing, etc. Gordon from Monty Racing got the job mainly because he attends the events I attend and knows how I run the boat and will usually be around if I have any issues/questions. He also is close by. These motors are VERY similar to the V4 OMC's and OMC is his specialty.
We decided to go with a moderate fingerport build with about a 8000rpm goal. I tend to put a lot of hours/miles on and typically will run 100+ miles a day when I am out. I wanted reliable power.
Here are some pics of the work so far. The turnaround time has been very quick and I need to tear my old motor down as the flywheel is getting lightened and all rotating getting balanced.
Gordon has been sending me pics and info about the project as it progresses. I asked if it were ok if I shared them via some of the forums and he was fine with it.
Heads cut and the angle changed a bit to Monty's specs. Should be about 145psi (pump gas motor)
Intake side stuffed with epoxy. I have been running Chris Carsons reeds for a couple years with reed block stuffers from the Yamaha 220 Special as well thanks to Wayne at Hydrotec
I should have the block back tomorrow and will take some finished pics.