Modify the MCI?? YES!

[tonyton]

Long story short. I came here a year ago and heard that these little EZ GO motors can be made to run 7000 rpm. More or less, I've spent a year and a ton of money trying to do what others had already done.
I had an old 350 block and a 295 head. It didn't have compression. Bored it and the head and deck were warped. Had it machined and it ran great, but leaked oil like a seive, the oil port was cut bad and I couldn't fix the leak.
Basically, I ruined it trying to bypass the port to installl an oil cooler.
I bought another 350 block and high performance head and could only get 180 PSI compression and ran to 5500 rpm. It needs to be bored or the valves leak, maybe both? So needless to say, I'm not lucky or experienced with this stuff. It was one problem then another.

I had bought a new MCI engine to run in my cart whiile I was doing these :"experiments". Now I need to rebuild the latest block to have a little more compression. Well, why not see why nobody does the MCI engine. There are some slight differences, but overall is the same motor.
Here's what I found that is different and this is what I did.

[tonyton]

Visible differences:
The head is a one piece unit. The exhaust manifold is part of the head.
The oil pressure switch was moved to outside the fan housing and the older hole was plugged. They just moved it to another pre existing hole.
The pollution breather has about doubled in size. It is slightly higher under the carberator, but extends further down the bock.
They removed two rows of cooling fins on the bottom of the cylinders and all of the fins on the backside of the head. They reshaped the fins around the oil return ports.
The whole ignition system has changed. The pulser, ignitor and ignition coil are all different.
The flywheel is gone. It uses a single piece stamped metal hub vs. a cast flywheel. It is lighter.
This picture shows the flywheel and the oil switch. Note the fins are smaller.

[tonyton]

Internal differences:
The valves are a different part number. I'll pull those and compare them tpmorrow. The oiling system for the head is different. They no longer have the overcam oil channel in the valve cover. It shoots out of a slit over the cam end. I couldn't figure out how else it was suppose to work.
The slit over the hole is where the oil comes out. The oil port to the cam is smaller. Probably to increase pressure. Stainless valves vs. stock. Can't tell the differences while they are installed. They might fit...

[tonyton]

Now for the difference that stops most mods and I didn't get a picture of it.
The pistons on the 350 MCI protrude beyond the deck about 1/32". This will make a smaller diameter 295 head hit the pistons, or the pistons hit the head, I guess. Any low cut head will hit and if it doesn't have a recess in the head, it will hit. The oil port to the head is in the same place, same diameter and the same gasket as previous years. That means, the only thing keeping the high performance head from working on this new block is the pistons. The part numbers are different and the newer pistons appear to have more material on the top. It is a flat piston design.
This is what it looks like after I removed the pistons and removed the extra meat on the top. They are now flat to the deck, and the high performance head does not hit.

[tonyton]

Here are the components that are used in this build:
MSD 6200 ignition, Blaster coil with HD wires
Walbro PZ 26 carberator and custom intake
Fast Fred Stainless Steel Valves and HD springs
Fast Fred Performance head
LSV sales Torque Cam
Custom built header and muffler system. Optional resonator or muffler...
MCI 350 Block STD bore

[tonyton]

When I was reassembling this engine, I came across a couple of odd things. I had tried a 295 head on this and smacked the pistons pretty hard. The cap bolts on the rods were not TIGHT. When I reassembled, the rods locked on the crankshaft. Either they were knocked out of round or the crank bent or something. I tired some barely used rods and they locked also. I wound up hand grinding the rods to fit the crankshaft, using lapping compound. They fit tight and spin free, but I still don't know WTH happened. It ran good even after I tried the head and put it back to stock. If it throws a rod, we know why. My fault. Don't try that at home!
Next, the best part

[tonyton]

I got it together today and installed. This is what it looks like. This is one year, 3 blocks and a couple heads later....
I started this one and it ramped up to 6K pretty easily. I didn't get to drive it, my tractor had me blocked and it was dark.
I'll find a camera man and film this. It may be a short run!
I may need help getting a video on here. I'm not computer, or, any wise...

[rib33024]

Nice work there tony, can't wait to see the video---

[tonyton]

Thanks, there are a couple small things that I forgot. The sheetmetal for the fan at the exhaust doesn't quite fit. The MCI sheetmetal may work fine with the old style manifold. I didn't check it. The old style metal has a hole that won't line up one of the MCI holes. It does fit, kinda. You could drill another hole in the sheetmetal or leave one bolt out. I left one bolt out. I'll be adding as I recall them and discover more.

[sabercat]

can't wait for the vid tony! question: any reason why you hooken the crank case breather the the end of the filter? on my g9 i have a simmiler k+n filter and in my set up i just bought a crank breather filter for the valve cover.
great thread btw very interesting!