Never had such a big difference and it hasn't been deck height.
I wonder if one bank has lots more crankcase compression as I guess at cranking that would help fill a cylinder?
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Never had such a big difference and it hasn't been deck height.
I wonder if one bank has lots more crankcase compression as I guess at cranking that would help fill a cylinder?
Though about that and I may do a compression test with the intake off.Quote:
Originally Posted by powerabout
This is what happens when I start screwing with stuff. No more paint. Maybe Ill do the mid like this to and just leave it bare aluminum with a coat of Shark Hyde on it.
Shark Hyde: http://www.sharkhide.com/mpinfo.html
Stuff is supposed to work very well
My Yortmaster :) More polishing to come and I have ordered some aluminum epoxy the aircraft guys use to fill some gouges/pits and the water intakes. They say it will match very well.
Attachment 302787
Making a decal for our local test lake that we call "Fake Lake".
Attachment 302817
Heres a blank one if any of you Yamaha guys want to add your own local lake text to it but I only have it with the pointer at about 95mph.
http://img.photobucket.com/albums/v3...psbb18eaab.jpg
Mid is ready for paint!
I sent the mid to Marty he rewelded the crack. I got it back and just wasnt confident in it witout adding some additional bracing. Its cracked twice in the same spot and without doing something different, probably going to crack again.
I came up with a plane to add gussets that cross the welded seams and tie both sides together.
Called ich Junker at Leading Edge Propeller and scheduled an appointment to do some welding yesterday. Everyone with welding experience who has looked at this mid have commented that the original welds where poor. Pretty but not hot enough and probably why it cracked. Again, I bought this mid used and am told it was a Bob Kottman mid but in reality, its a used mid and I rolled the dice.
I made the cross braces and fit it together then Rich welded it building up an "arc" of material in the corners that tie into the original plates that were out in each side. I told him it didnt have to pretty, just strong. The front plate ties right across the motor mounts and should add a lot of strength.
Regardless of the previous cracking, I like the idea of tying the two side together if possible. Even if the crack opened up again I think this adds a lot of safety.
Having Rich's belt sander to shape the braces for a tight fit sure made it easier. On a side note, I was using this thing once when the belt broke. Wrapped around my should and slapped my back like I had been whipped. Had a welt that lasted a week and hurt like hell. Rich said in all the years he has stood in front of it, he has never been hit.....
Original crack:
Attachment 303202 Attachment 303203
After Marty welded. He welded it from both sides:
Attachment 303204
You are patient guy Demeanor.... Nice work..
And this is what I had rich weld in for me. Tuners just barely fits :D
Attachment 303205
On this side of the front plate you can see how it will be tied right into the pockets for the lower mounts. My thinking was this has to be where the load is transferred into the mid and tieing into the angles here will add the most strength.
Attachment 303206
Front and back plate welded in. My 298 pound motor is probably back to 300 pounds :eek:
Attachment 303207
Just enough room for the tuner:
Attachment 303208
I now have $1500 in a mid section and I got a great deal on. Probably getting into where I could have had Chaz build e a tubular one....maybe.
Marty also surfaced it and said it was .028 out. Don know if that was from the crack or contributed to it. Going to check it again now that its been welded on a bunch.
Thanks. Its now a Kottman/Powell/Junker/Cromley mid lol but I like the end result and if it breaks now, its all on me. This is what I wanted done and its my ass in the drivers seat at 95mph. I think even in the event of a failure this mid would hold enough integrity to get me home safe.Quote:
Originally Posted by JP Love
Mr D that is what all the extra work is for --- SAFETY !!! As I told my dive students "if you don't live thru it --- It ain't worth it!" Keep up the great work- we are all learnin with ya. GaryQuote:
Originally Posted by Mr. Demeanor
It's a bit of an uphill battle when your boat has far exceeded the inteded use, ie: extra 50 hp and the forces of going 90+mph. Your doing it right. Rebuilding and redesigning things to handle the extra forces the stock motor would never see. Yamaha needs to hire you. Lol. Keep it up.
Dave
Chris, now that you've made it this far.......time to start planning a chopped OX66 front half with a Monty tuned Motec system......I bet he can easily get 200hp+ with that setup on pump gas...
Mike, do you know the throttle plate size in the OX66 front half?
Unfortunately no, but what I do know about the OX66 front half is it is much bigger than the excel/prov 200 front half. Kinda like comparing a merc 10 petle to a 14 petle front end....there's plenty of area that needs to be stuffed on a OX66 font half, along with much bigger reed cages....
Crank case injected HPDI front half with 2 cyls cut off. Hmmmm
Right now I just need to get it running and enjoy it. Could use a bigger prop as well.