GSXR "DOT" head on my GS1100

[Cipher]

Sacrilege! Put Honda wheels on a Suzuki!



No Sir. They are, in fact, Astralites

Yes the poor Honda wheels must be mortified.

[slayer61]

Mock up time while other bits get finalized...

Carbs stuffed in...


Fuel tank "on"...

that's gonna take some fettling.

After removing petcock, signs of improvement!


Head mods in general

With that small piece of aluminum welded in place, the mating surfaces will actually meet up all the way around the head gasket!!

[GregT]

For what it's worth, those heads like the cams on 104/104 lobe centers. If you weld in that piece of alloy, bolt the head down to a flat surface while it's done. Last thing you need at this point is distortion. .
I'd also probably have looked for alternative carb rubbers - angled. I've personally never run CR's on that much angle.

Very interesting though, carry on.

[slayer61]

Thanks Greg, that's good info about cam timing. I will certainly put it into the data base. Yes Sir, I'm familiar with metal distortion. If we get that much heat that the distortion rears it's ugly head, we have access to a milling machine & a lathe. Never seen angled carb rubbers either, but if the CRs don't like running down hill, I could swap them out with the TMs on the GPz.

be safe!

[slayer61]

As some parts come in, onto the es they go. Clutch pack was within spec and reinstalled with OEM clutch cover gasket.


Pictures back from the welder (Thanks Steve!) setting up the head.

[slayer61]

So over the weekend I dressed the weld on the head using a half round file. It'll work fine for this situation





And I faffed around with AN lines and oil coolers





It's so crazy... these parts were meant to go together!

[slayer61]

Parts have arrived from Japan. Thanks Pops!




I also got the cylinder block removed to replace the base gasket & measure up ring gap. The pistons look to be in great shape.

[GregT]

I see the cams you've got go in on 103/105 LC's. That'll work fine. My 104/104 gives a slightly wider power band but uinless you dyno it you'll never notice.

[slayer61]

Thanks for that Greg. I have seen numbers all over the place with regards to LSA for this motor. I asked on another site where this swap has been done before and was advised as wide as 110 degrees. I think part of the dilemma is because of the slingshot head, a high revving, short stroke motor, combined with a giant slug of a bottom end that will never rev as high as the slingshot 750.

On a more somber note, I pulled one of the compression rings from the no. 1 cylinder to measure the end gap...... and I'm right at the end of the acceptable range.

Now I need to decide how much more money I want to spend on this project.

Speed costs. How fast do you want to go?

[GregT]

I was building the 750's with that head for both roadracing bikes and speedway TQ's. The TQ's are fairly heavy vs a bike and single gear on a 1/4 mile oval. You soon learned what worked.
When the GSXR 750's came out most tuners thought the very wide LC's of the aircooled 16V engines were the way to go - 110/112 for a full house 1150. Wasn't till Yoshimura and others actually started serious dyno time that it was realised GSXR's were different - even though the heads are based on the same patent.

[slayer61]

Long time, no update. Still waiting for credit cards to cool down a little bit.

1). The buggy is "finished" for the season. More to come next year.



2351073.jpg

2). My wife has a new bathroom.

3). I have been in contact with APE regarding piston kits and machine work of same. If they provide the piston kits, boring & honing is only like $150 for an air cooled 4 cylinder!

[93Bandit]

What's a DOT head? Sorry, I'm a noob..

[slayer61]

What's a DOT head? Sorry, I'm a noob..

The DOT head came from the 88-89 "slingshot" GSXR750 short stroke motors. Called the "DOT" head because of the dime sized casting on the sides of the head. The DOT!

5737364314_ee6ef58fe1.jpg

Pic shamelessly borrowed from the interwebz.

The head uses the same bolt spacing as the GS, has a smaller chamber, larger valves and a "semi-down draft" intake tract. As such, I'm (fingers crossed) hoping to make 20-25 more horsepower just bolting on factory parts.

[93Bandit]

Ah, OK thanks for the explanation! I was thinking DOT had something to do with Department of Transportation but I couldn't figure the connection. Cleary over thinking this one haha.

In other news, a GSXR750 would be a hoot 'n' a half

[Blower]

Interesting project!

I will do slightly similar modification, but with modified Bandit 1200 cylinder block, extra oil pump for head cooling and oil drain pipes from cylinder head to the engine block.
Engine bottom is from 1984 GS1150. Most difficult thing will be extra oil pump, but I have a idea how to install it in the oil sump.