Another project dreamed up during a cold, wet winter not driving:

Two sets of these GSXR 600 K3 throttle bodies:

An spare M20B25 intake manifold

A number of hours with  a hack saw, angle grinder and piller drill on the lathe with a milling bit later:

And you get a nice manifold ready for some ali tubes to be welded on:

The manifold will slot right on being the mounting face of a stock intake as can be seen below:

The nice thing is that the provision for the oil return is already integrated to there's not need to come up with a solution for that:

The stock fuel injection locations will be used, those on the GSXR will be plugged.

The GSXR individual throttles need spacing further out than that standard so some modification will be required to make this work. The K3's have a second set of throttle butterflys controlled by the ECU, these will need removing and the extra holes plugging. The end piece as a TPS integrated. The diameter of the GSXR bodies is 38mm at the engine side, they are tapered and open up a bit more to the intake side. Based on recommendation be other ITB users on E30Zone I picked these over the lager bodies from the GSXR 1000, they are too big for the engine. The 600's should be about right.

The plan is to use tubing to connect the throttles to the manifold so that its possible change the lengths and see what the does to the power!

Two sets of ITB's give you 4 bolts to screw them together - not long enough for 6 throttles. The solution is to chop the thread off two of them and the head off the other two. Then the 4 bits are welded together to create one long bolt.

After welding the join is ground down to make it round and smooth.

Which means with temporary spacers its all one piece now

I've been research idle control on these. The GSXR has a manual fast idle lever on the bar. Some people have experimented with a stepper motor to control this, but I think I'll probably employ the solution that BMW themselves use on the M3's - a common vac pipe connecting all 6 cylinders and a standard ICV bolted up to it. I can use the second set of injector holes that are directly on the throttle body.

A bit more progress today in preparation so the manifold can be completed. I couldn't quite run the pipes at the same angle as the holes in the head due to using the stock manifold. I've opted for a shallower angle that will result in a relatively smooth transition between the pipes, manifold and head. I could always completely custom make a manifold at some point in the future.

The other big step was to get the throttle bodies properly spaced. I cut 10 spacers on the lathe exactly 11mm wide. There still a lot to including the minor issue of welding the pipes on - not sure how this will work but I suspect it will involve doing a lot of grinding to clean it up!

Ali tubes cut

Quick test fit

"just" needs to be welded!

And from the other side (yeah the throttles are the wrong way round ;o) )

Spacers cut on the lathe to space each throttle 11mm wider than they are on the GSXR

The ITB projects a bit quiet right now as we're trying to get the car ready for paint. Part of the this is a set of louvres.

I've probably spent 16+ hours on the lathe with these, the curves were right headache!

Test results so far are OK, but not perfect. The thing I'm have the biggest problem with is getting a nice start and finish. I think I'm going to have to make up a wooden die I can use to hammer a nice finish to the start and ends.















They are for this machine:

After spending a lot of time eyeing up the location for the wipers I came to the conclusion that 90 degrees would work best for us. After looking inside the gearbox I found that we have a 110 degree drive gear (which matches the sweep measurement I took a while ago). So I ordered a 90 degree drive gear.

Wiper wheel boxes installed. I had to thin down the fibreglass on one of them as it was too thick to mount the wheel box.


The boxes are fairly in-line.


Motor mounted on a metal plate. I plan to move the hoop for the motor a little hight so the motor is held a little better. Its seem to hold fine as it is however I would feel better with it moved.



Tubes cut to length and flared, good that we had all of the tools from installing the brake pipes as they came in perfectly for this job.



All the parts ready for install. We bought some chrome tops for the wheel boxes as Marlin supplied rubber ones. I am using the rubber ones for fitting to avoid damaging the the chrome ones.



Wipers installed, still need to cut the arms to the correct length.



Tubes Installed.




Wipers in motion.


Washer jets installed.

New scuttle side panel without louvres compared to the original with louvres. The new one also now has folded back edges which gives a much better edge.

New scuttle side panel on the passenger side with folded back edges.

A few more things checked off the list:

• Finished the scuttle side panels
• Opened up the indicator holes on the scuttle to fit the new ones
• Rear end break down
• Step one of filling the seat belt holes in the tub

I recommend everyone take their tub off after a year and check for rust issues, we've got a few area's that need to be cleaned up and protected.

I took some video with my phone so its pretty cruddy quality but shows the wiper motion:

Rough fill in of the holes in the tub with 8 layers of glass to give it plenty of strength.

Tub hole cover from the back

New side repeaters fitted - these need the hole enlarging a bit.

New scuttle side panels sitting snugly with the new repeater above.

Vent hole cut and cover fitted

Mirror holes filled in (the ones nearer the front they were in the wrong place!) and vent holes.

Back of tub sprayed black - hides all the modifications.

Bonnet cleaned up ready for louvres and the hinge holes sunk slightly further to allow the screws to sit more flush.

Fibreglassing experiment - this will form an attachment for any future rear diffuser.

Fibreglassing experiment - this will form an attachment for any future rear diffuser.

After not having much success with the bead roller I went to go see http://www.coollouvres.com/ today, here are the results, I'm really happy with these:

All the body panels are off and ready for paint!

Done some work on the new clutch setup:


Bolts through the top of the scuttle to hold the clutch master


Wilwood clutch master mounted to wilwood clutch pedal frame and then bolted to the scuttle.


The scuttle will need some re-enforcement as does the pedal box.

Connected up the clutch this evening, the bite point is right at the bottom of the pedal travel, but is really controllable. It means the clutch will sit higher up that the brake at the moment so we'll have to see how it goes. The whole scuttle bends all over the place so reinforcement is required now.

And finally warm weather - well not freezing anyway :o)

The new clutch system is now installed. The master cylinder has more than enough capacity to dis-engage the clutch without pushing it all the way down. The pedal position can be adjusted with the thread on the master cylinder so we've moved the clutch inline with the brake pedal. Due to the different leverage on the clutch it is now very easy to use. Only time will tell if all the problems are solve once we can go further than the end of the drive!

Constructing the scuttle panel re-enforcement plate

Heating along the cut to bend the 3mm steel.

Re-enforcing the pedal box

The metal is welded on in various places to strengthen the pedal box.

Welding complete on the pedal box

Scuttle re-enforcement plate painted and bolted in place, it bolts on to the bar than runs from one side of the car to the other. There is no flex at all when the clutch is operated now.

Pedal box and new clutch assembly reinstalled in the car.

Mark 2 exhaust hangers, these use the rubber mounts from a BMW 840Ci Sport. There is 3mm steel plate than connects the exhaust boxes to the hangers.

A new bolt is welded in on the right side of the hanger, the other is the one form the fuel tank strap.

Driver side bracket, this one has some stress on it but the rubber mount is off a 12 year old car so the rubber has gone soft. A new pair will need to be ordered to finalise this.

The plates need a coat of paint and this can be marked as done.

Dash board re-trim without glove box (wiper motor in the way)

Rear of re-trimmed  dash showing pod for speaker

Divers side behind the dash

Test fit on car, the mount holes needed drilling out as the paint had filled them a bit.

The speakers could do with a grille mesh to finish them off but other than that it is coming together.

Rear lights installed with new waterproof plugs - a bigger job than you might expect!

Nose cone and centre console

Nose cone fitted.

hmm pretty colours

Starting to piece together the centre console

Two supports cut and shaped to get the angle of the radio correct with enoughclearance for the rear of the radio.

Radio supports glued.

Just need to make up some sides to hold the midbass speakers under the dash.

Mk 2 fuse holder bracket

This bracket also holds the wiper motor. The clamp has been moved up a bit to reduce flexing.

The centre console is taking shape with a small recess to keep your glasses.

Managed to find some room to fit a speaker above the steering column.

There's some sides and top to try and keep the front and back separated as much as possible.

Once the dash is in you can't see it any more.

Passenger side speaker

Driver side done

This side still needs some more brackets so it's all solid.