Cool Gt750 motors

tz375 · Post by **tz375** » Fri Dec 25, 2009 11:33 pm

Eric, The first picture is an Ocelot, but what are the lower two and who did teh conversions. The left looks like a TR block which has been lightened considerably, but may be a Gt block and the right one has the neatest downdraft conversion to a 73 block if that's what it is.

Except the stamped numbers.

32-50 means 32mm down/tall (same thing) exhaust 50mm wide. Yes/no?

And 32 can't be machined out a GT block, so is that a Gin ewe wine TR block?

What's the story behind that picture?

edit: i thought those barrels looked familiar so i tracked them back to the source and the words Harris Barton, or Governors bridge M/Cs come to mind. But I'm not much wiser about the provenance.

Suzukidave · Post by **Suzukidave** » Tue Jan 19, 2010 10:50 am

Richard , didnt i see a picture where you tried your hand at lightening a block like the left one ?

tz375 · Post by **tz375** » Tue Jan 19, 2010 2:28 pm

Shhhh. that was supposed to be a secret.

I'll probably use that lightened block for a reed conversion. It's an A so it has too much intake timing for a street ride IMHO.

Suzukidave · Post by **Suzukidave** » Tue Jan 19, 2010 3:13 pm

oops ..my bad ... you want me to delete my comment ?

tz375 · Post by **tz375** » Tue Jan 19, 2010 6:08 pm

No. there's no secrets here - apart from my port numbers and those magic numbers (yeah right!) are a secret.

In fact they are so secret that even I don't know what they are.

Just don't tell anyone about going through the water jacket to weld up the or about welding the transfers to get more transfer area or welding the crankcases to get more flow to teh bottom end, .

There is so much metal in those blocks it's crazy. I suppose it does help to keep them from distorting though because the crankcase has really low torsional rigidity.

Suzukidave · Post by **Suzukidave** » Tue Jan 19, 2010 7:03 pm

Did Bill find time to finish your street porting ?

two-stroke-brit · Post by **two-stroke-brit** » Tue Jan 19, 2010 7:25 pm

hey zooke, are they special 8mm head bolts i see with a shoulder under the head

,
ifso why.
cheers mark

Suzukidave · Post by **Suzukidave** » Tue Jan 19, 2010 7:36 pm

I saw those also and thought they were pretty cool .. they would be lighter

tz375 · Post by **tz375** » Tue Jan 19, 2010 10:31 pm

I'd hypothesize (sounds better than guessing) that they are 10mm bolts that are waisted down to more or less the same diameter as the root of the threads which would be about 8mm.

GSXR crankcase bolts look just like that. They are 10mm at the head and threads and about 8mm between. Just as strong as a solid 10mm but lighter.

Suzukidave · Post by **Suzukidave** » Tue Jan 19, 2010 10:57 pm

Thats a great idea Richard .. i have a bunch of GSXR engine assembly bolts that are the waisted type .. i will look to see if there is a set i could put together

Cool Gt750 motors

Cool Gt750 motors

special bolts