Project; Turbo GSXR Slingshot

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WARNING, THIS POST CONTAINS PICTURES OF ENGINE COMPONENTS IN DESTRESS!!


Intake valves and piston tops are glazed heavily, I'm sure someone knows why this has happened but I can't be arsed to think it through now.










Moving onto the valves now, either get all the bad news out the way or find a positive...
 
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It appears the valves are only seating on one of the angles as well.

Certainly haven't got a big surface area to seat on.

 
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The outer part of the valve doesn't touch the head though, its only the black line thats been seating the valve.
I was under the impression that the outer angle of the valve should seat on the head?

Just priced up the pistons, £470.
 
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The valve seating has been explained on another forum and you're right JamesRJ, it seats on the centre 45 degree angle with the other angles improving flow.

I also checked the wastegate bleed valve to see what pressure it opened at, it was replaced and set by John. Got to 2 bar and it hadn't budged.
Opened it up and the bolt was wound in until it touched the ball, wouldn't open at any pressure like that.
 
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Things are still moving forward, new pistons arrived and are with a set of barrels waiting to be bored out.



The old set were bored too big for the pistons, piston to cylinder clearance according to MTC should be .002" - .0025"

Head has been cleaned up and checked for flatness on a CMM, its 5 microns out so it pretty damn good.

Temps creeping up on the dyno mean I need a bigger rad.
Only way thats fitting is new header design, so after a few hours trying different ways I pretty much started again.


Didn't like this one




Got rid of the lower bend and went with this design




Ordered more bits...




Then its cutting, grinding, linishing and welding




 
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Only 316 tube and fittings I could find were on ebay.

V band clamp was from Darkside Developments and is really nice, cheaper and much better quality than those on ebay.

Got the number 3 header in now but had a mare with the welding as I didn't get the fit tight enough, then broke through the pipe tidying the blend up inside! Its ok but its left its mark.

Kind of ruins the lines but there's a frame to avoid...

 
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Thanks, it's not bad but I think I could do better if I practiced more and maybe had a bit of tuition. I'm happy with it though.

Rebore is done so I need to sort the pistons out to remove potential hot spots then cc it again and work out comp ratio.
 
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Finally got time to finish the headers



Got a full size rad in there now and it should clear the front wheel easily



Pistons are with a mate getting the sharp edges around the valve pockets removed, then it'll be rebuild time.
 
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That's a good point. I suppose if you're on the move the heat just gets blown back, just seems a bit wrong to me, but then I don't design bikes or turbo them to an inch of their life so what do I know :p
 
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Shirley is reserved for 'those nights' :eek:

As said above, its common for IL4's and my gsxr 1100 with an Akra system runs closer. Only an issue when stationary or slow riding.
 
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Made an adaptor up to get from the twin 38mm to the 51mm

Its not going onto the v-band but its good to hold it in place while its tacked, got some trimming to do to move it up as well.

 
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Been slow on this lately but its finally moving.

Cc'd the piston and bore, got a 1.5mm spacer under the barrels instead of dishing the pistons this time.



If I use a .018" thickness head gasket it'll give me 9.14:1 comp ratio with 1.77mm squish.

Little comparison between the new and old pistons, both MTC turbo but the newer ones have much more meat.



Installed the pistons in the barrels on the bench the got a mate over to help hold the barrels up whilst the gudgeon pins and buttons were installed.
Was a little tricky but went well and easier than trying to get 2 pisons at a time into the barrels.



More updates once I source a head gasket.
 
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