As the clutch pedal is a lever with a fulcrum close to the top end, a small amount of adjustment will translate to a larger amount at the bottom end where you press with your foot.
I found that eliminating clutch drag in this way made a huge difference to my gear change.
2 Likes
Not a hard task to do, but it is awkward looking upside down in the footwell trying to undo a locknut on the clutch pedal!
I too found this made a big difference on my old mk3.5, but on the mk2 I’ve just adjusted away any pedal freeplay and it hasn’t made any difference. Next to try is adjusting past the freeplay so the resting position of the pushrod is engaged few turns into the master cylinder.
Edit: Spoke to a trusted MX5 expert who recommended adjusting a few mm into the piston’s travel. This seems to have done the trick for moving the biting point back to roughly the mid-point of pedal travel. (and only took a few minutes second time around!)
Gearchanges have definitely less resistance, there’s still some stiffness but better than before, probably becuase the clutch is disengaging further than it was for same foot-effort! I’ve been running the Ford Motorcraft XT-M5-QS oil that I had great success in my NA 6speed but it hasn’t seemed to have made any difference in this 5speed (after 500ish miles) looking on Miata.net the reviews seem to all say great for 6speeds but more of a lottery in 5speeds.
Next step might be to swap over to some Valvoline Syncromesh MTF which seems to have more luck with smoothing out notchy 5speeds. Not available in the UK but Rockauto comes to the rescue again 
I think my trouble is that my old NA 6speed had such a lovely rifle-bolt gearbox (even if I did fluff 4-5th changes) that I’ve been spoilt.
WOW WOW WOW only just seen this thread…
Amazing work, car looks amazing 
1 Like
Did a 130 mile round trip today to Ant Anstead’s Cars & Coffee with some other club members. The changes to the clutch seemed to have made improvements. The gearchange is definitely better than it was, and the biting point remained in the middle of the pedal range, even after crawling in traffic for a few 10 minute stints, so the heat shield seems to be working. Still have some judder left to resolve but that’s for another day. The Tipo 184 is a lovely piece of kit based on an MX5, surprisingly long car much bigger wheelbase than the MX5 it’s based on!
3 Likes
While you were there did you hear of any progress toward making the Tipo184 road legal?
Yes if you look in the background the red one has mudguards, lights, exhaust cover etc. Pretty sure they said they had taken it through IVA (or whatever it’s called now)
2 Likes
Be still my beating heart 
2 Likes
Hello mate, was great to meet you today and thank you for answering all my questions and letting me have a good look at all your hard work.
In return I can offer you a photo of your Icon in motion! Sorry about the quality, my wife was trying to get as many mx5s in as possible, I think you can just count 10. 
3 Likes
Thanks for the photo! great to meet you too, it was good to meet lots more MX5 owners. Hope the turbo comes back sorted 
Looking at the photo I need to check something isn’t hanging down under the diff !
1 Like
The Rocketeer conversion uses the Mazda IAC valve to balance banks & control idle. It’s vented to a small foam air filter which is REALLY NOISY 
especially at partial throttle, so I’ve been experimenting with different solutions. First off was a bigger filter using a carb trumpet sock, this helped somewhat by reducing noise by about 50%. Second attempt was to add a restrictor into the ICV inlet and compensate by opening the bi-pass bleed screws on both TBs. This ran fine when cold but stalled when hot (or was it the other way round) Third attempt seems more promising where I have removed the filter and ran a vacuum pipe to one of the main air filters. This has not quietened it down much at idle but seems to have completely got rid of the hiss when on partial throttle. The extra resistance in running a vacuum pipe (400mm) has been compensated by a very slight increase in TB idle bi-pass but not enough to affect the running it seems. Going to run with this for now and see how it goes.
Carb sock 1st Attempt
Diverting to main air filter
Also tidied up engine bay a bit by re-fitting foam strip to the top of radiator so air goes through rather than round. When the undertray goes back on I’ll fit a bigger one at the bottom
3 Likes
Relocating the ICV filter didn’t work on cold starts so it’s back to the sock solution which is better than before but not 100% quiet.
Last weekend was the job of fitting the dual roll bar setup from TRLane which is needed for me to go on track at Spa later this year. I roped in my Uncle to help again and we got it all fitted & finished in a single day with the two of us
The ‘fun’ part of trimming the razor sharp parcel shelf !
The re-enforcement plates were way off so had to be cut in two! then the ABS wire grommet trimmed to fit
All trimmed, fits nicely but I’ve lost my windbreak speakers 
anyone recommend some small stand alone speakers to fit inbetween the bars?
Seats fit nicely but downside is I’ve lost a good 2" of rear seat travel / tilt which is a big blow for a 6+ footer like myself I tried driving with it this week and covered about 150 miles but it’s definitely not comfortable so I’ve picked up a spare set of drivers seat rails so I can swap in/out the Elise seat and try that for a while see which I like best.
1 Like
Nice work!
I’m currently looking at bars myself and have seen that the gcr range from gc fab are made so that the seats can go further back, it’s not a huge problem for myself since my pro2000’s can’t go any further back due to how wide they are and I’m not over 6ft, could be helpful for someone taller like yourself
1 Like
Tidied up a few things today, including refitting the undertray to hopefully help with cooling, and raised the suspension back up by 10mm all round as it was grounding on the entrance to my drive with two people in the car.
The big debate with tuned cars, ordinary or Super unleaded? I’m noticed a little pinking/slight knocking in higher gears below 2500rpm picking up from slower speeds. Running 95ron at the moment so I investigated what I could do to try and stop the pinking/knocking.
First step was to replace the OEM fuel pump for a DW200. The factory pump is generally accepted to be good for 150-200 bhp maximum and the Rocketeer is running 271bhp, not only that but it has x2 extra cylinders to feed.
Once replaced, this seemed to make quite a difference to the engine. It was noticeably more lively and revved freer from cold. It got rid of some of the pinking but not all. Next I drove the last couple of gallons of 95ron out of the tank and replaced with £50 of Shell Vpower 99ron. This has made an additional improvement, now I’m not sure how much pinking there is left (if any) over the Rocketeer’s ICV (idle control valve) sound. The noise is mainly between 2000 - 3000 revs when you’re in a higher gear like 40mph in 4th, or 50mph in 5th.
Next step was to fit an in-line fuel pressure gauge to see what the in-tank regulator was regulating at. The Rocketeer kit comes with an engine bay regulator that gets fitted to Mk1’s as they only run 38-45psi and the Jaguar engine needs 50psi (3.5 bar)
However mk2.5 cars have an in-tank regulator that runs at around 60psi and because of that there’s no fuel return line in the engine bay back to the tank. This makes fitting the kit FPR a right pain! So the company mk2.5 demonstrator runs with factory system at 60psi which is how mine is at the moment. Mine’s at approx 64psi (4.4 bar) but bearing in mind this is not an expensive gauge I suspect that’s give or take a few PSI.
But was this extra fuel pressure something to do with the pinking? normally it’s the other way round (too little pressure means lean = knocking) next step was to fit an AFR gauge & sensor to monitor those readings if/when it pinks.
And the results?
- AFR Idle at start 12.7
- Warm idle 14.7-8
- Cruising 14.4-14.8 (most of the time reading 14.6)
- WOT - 12.5 - 12.8
From what I know these look quite good readings don’t they? The ideal ratio, or the “stoichiometric” mixture where every bit of fuel is burned = 14.7:1 which is pretty close to the cruising ratio I’m getting
Conclusions?
The DW200 pump coupled with running 99ron fuel seems to have got rid of most of the pinking, I can’t tell if there is any left as the ICV sucking noise seems to drown out any other subtle noises in the engine bay! I think I need a second opinion for someone to sit in the car and listen with me in case I’m amagining things… 
5 Likes
A couple of other things worked on this weekend, I finally got round to adapting the ECU mounting brackets to fit the MBE ECU in place, in the passenger footwell.
Fitted some Delrin door bushes I’ve had for a while but never got round to using
And fitted a PU front splitter (copy of an OEM one) which took an awful lot of heating & persuasion to get to fit!
Along with a spare V6 badge tucked away in the front grill which I can’t decide if I’m keeping or not. But the OEM splitter copy definitely looks like it should have been there all along and curiously doesn’t lower ground clearance at all.
5 Likes
This arrived today, after a six week wait from Guardian designs, should give me lots more legroom. It’s a Corsa-330 (which actually measures 325mm across) and still utilises the NBFL airbag. The stock wheel for reference is 365mm.
Pleased with the quality, they make them to your spec, colour, leather & stitching type hence the wait.
8 Likes
Fitted the wheel yesterday after work, needed a bit of minor adjustment to get the airbag lined up right & horn working but what a difference to the driving position it’s made. These things aren’t cheap but justify it by the difference they make in comfort! I can still see all the dials apart from the top part of the silver surround.
It’s fitted in conjunction with a Spacershop 50mm steering wheel spacer specifically made for the NB airbag cars. For the first time I can comfortably get both my legs under the steering wheel with room to spare when my feet are at the top of the pedals
showing difference in size:
9 Likes
that looks very nice. I will be taking a look at their offerings. Out of interest how tall are you?
2 Likes
Wow, that wheel looks superb and such an elegant solution to use the existing airbag.
2 Likes