Mx5 Rocketeer V6 Conversion Project
Discussion
This topic will always have my attention! Hope you're back in a position to move forward soon.
On the emerging collectability of mx5s in general - I'm aware of a concours, fully original early mk1 with 8k miles on the clock seeking last month for over £15k. Which I have to admit I thought was mental. There are still loads about, but the rate of loss is starting to accelerate really quite quickly...
On the emerging collectability of mx5s in general - I'm aware of a concours, fully original early mk1 with 8k miles on the clock seeking last month for over £15k. Which I have to admit I thought was mental. There are still loads about, but the rate of loss is starting to accelerate really quite quickly...
Another update on the MX5. Not V6 related yet sadly, but that will be coming soon now I hope.
Since I've had the car, the steering has felt rubbish. I have had suspension alignments done and it helped the overall handling and feel of the car, but the steering itself still felt odd. The best way I can describe it is that when going round a large roundabout as you began to accelerate and the steering wheel loaded up it would almost feel as though it was pulsing in your hands. Not enough to deflect you from your driving line, but disconcerting and not conducive to quick or fun driving.
So I thought I would try depowering the steering. This is a slightly controversial mod as some people swear by the increased steering feel and say it is not too heavy while others think you are mad for deleting PAS. I read around the subject and came to no definite conclusions, so thought I would give it a go. The reason for trying it is that I wanted to make sure it was the PAS causing the strange steering feel, and so by deleting it completely I could eliminate it as a cause, and because my TVR was non-assisted and I loved it.
I bought a second hand rack, and stripped it. There are various ways of depowering, such as looping the fluid lines, but this tends to make the steering heavier than it needs to be as you are still moving hydraulic fluid around. A more complete (but irreversible method) is something like the 'Flyin Miata' guide.
After stripping the rack, there are basically two things that need to be done. Firstly, the internal piston needs to be turned down so that when the fluid lines a plugged, the piston is not trying to compress any air. Thus:
IMG_20180815_082158 by Jon Fellows, on Flickr
The next step is to take the pinion shaft, and weld a spline up. If this is not done, the spline can introduce to play into the steering (normally the high pressure fluid takes up this movement if I have understood it correctly). So a buddy at work who is good at such things welded it for me:
IMG_20180817_132438 by Jon Fellows, on Flickr
The rack is then reassembled with suitable lubricant, the fluid lines plugged and the pre-load on the pinion set up.
IMG_20180901_103523 by Jon Fellows, on Flickr
Until the rack is done. The tart in me also insisted on painting and cleaning the rack, and I took the opportunity to put new boots on as well.
IMG_20180901_121536 by Jon Fellows, on Flickr
IMG_20180901_121523 by Jon Fellows, on Flickr
Obviously you then have to remove the old rack. This was a filthy job, but I got there eventually, and I didn't even cut the hoses; tempted though I was at various stages throughout the removal!
IMG_20180827_130930 by Jon Fellows, on Flickr
It was then a case of fitting the new rack, having measured track rod end positions etc to get the steering near where it should be in terms of geo. I also centred the steering wheel using the very newest technology...!
IMG_20180901_125803 by Jon Fellows, on Flickr
And fitted:
IMG_20180901_135805 by Jon Fellows, on Flickr
So, was this a massive success? Does much glory accrue to me?
Having driven it, the steering is too heavy for me for road use. I can see how it would be great for a more track focussed car, but for (almost) everyday use it has a little too much heft. This is not helped by the fact that my physique suggests more of a poisoner than a fighter... However, success was had in that the weird pulsing was gone. So definitely an issue with the PAS (if I had to guess from the depths of my ignorance I would say the gating valves for the PAS fluid in the rack are letting by), which I wanted to diagnose before carrying out the V6 swap. So a successful diagnosis, and I've never taken a steering rack apart before so I learned too!
Next step, back to the V6...!
Since I've had the car, the steering has felt rubbish. I have had suspension alignments done and it helped the overall handling and feel of the car, but the steering itself still felt odd. The best way I can describe it is that when going round a large roundabout as you began to accelerate and the steering wheel loaded up it would almost feel as though it was pulsing in your hands. Not enough to deflect you from your driving line, but disconcerting and not conducive to quick or fun driving.
So I thought I would try depowering the steering. This is a slightly controversial mod as some people swear by the increased steering feel and say it is not too heavy while others think you are mad for deleting PAS. I read around the subject and came to no definite conclusions, so thought I would give it a go. The reason for trying it is that I wanted to make sure it was the PAS causing the strange steering feel, and so by deleting it completely I could eliminate it as a cause, and because my TVR was non-assisted and I loved it.
I bought a second hand rack, and stripped it. There are various ways of depowering, such as looping the fluid lines, but this tends to make the steering heavier than it needs to be as you are still moving hydraulic fluid around. A more complete (but irreversible method) is something like the 'Flyin Miata' guide.
After stripping the rack, there are basically two things that need to be done. Firstly, the internal piston needs to be turned down so that when the fluid lines a plugged, the piston is not trying to compress any air. Thus:
IMG_20180815_082158 by Jon Fellows, on FlickrThe next step is to take the pinion shaft, and weld a spline up. If this is not done, the spline can introduce to play into the steering (normally the high pressure fluid takes up this movement if I have understood it correctly). So a buddy at work who is good at such things welded it for me:
IMG_20180817_132438 by Jon Fellows, on FlickrThe rack is then reassembled with suitable lubricant, the fluid lines plugged and the pre-load on the pinion set up.
IMG_20180901_103523 by Jon Fellows, on FlickrUntil the rack is done. The tart in me also insisted on painting and cleaning the rack, and I took the opportunity to put new boots on as well.
IMG_20180901_121536 by Jon Fellows, on FlickrIMG_20180901_121523 by Jon Fellows, on FlickrObviously you then have to remove the old rack. This was a filthy job, but I got there eventually, and I didn't even cut the hoses; tempted though I was at various stages throughout the removal!
IMG_20180827_130930 by Jon Fellows, on FlickrIt was then a case of fitting the new rack, having measured track rod end positions etc to get the steering near where it should be in terms of geo. I also centred the steering wheel using the very newest technology...!
IMG_20180901_125803 by Jon Fellows, on FlickrAnd fitted:
IMG_20180901_135805 by Jon Fellows, on FlickrSo, was this a massive success? Does much glory accrue to me?
Having driven it, the steering is too heavy for me for road use. I can see how it would be great for a more track focussed car, but for (almost) everyday use it has a little too much heft. This is not helped by the fact that my physique suggests more of a poisoner than a fighter... However, success was had in that the weird pulsing was gone. So definitely an issue with the PAS (if I had to guess from the depths of my ignorance I would say the gating valves for the PAS fluid in the rack are letting by), which I wanted to diagnose before carrying out the V6 swap. So a successful diagnosis, and I've never taken a steering rack apart before so I learned too!
Next step, back to the V6...!
Lewis's Friend said:
It was then a case of fitting the new rack, having measured track rod end positions etc to get the steering near where it should be in terms of geo. I also centred the steering wheel using the very newest technology...!
That's bloody genius, I'll pinch that when I replace the rack on the TVR 
Max_Torque said:
shalmaneser said:
The process you're thinking about is sand casting about which I have less experience and might well be cheaper. Looking at the finish of the sump (kind of grainy) it could well be sand cast and as you suggest this would be cheaper. However there are much increased risks of flaws in the casting and porosity as the aluminium can't be pressurised as it's poured in so there are more likely to be air bubbles within the casting.
Simple sand cast parts, where the cores can be hand packed and molded from basic wooden tools cut either by hand (simple parts like that sump) or CNC'd are actually pretty cheap. These days, you could have a prototype done for less than £500, and if that comes out ok (usually does for something as basic as a sump pan) then a low number of production parts will be really cheap (probably get a couple of hundred for less than £25 each, but they will obvs need a finish machine for faces and holes etc)For a sump like that the casting flaws etc won't matter quite so much, as the part can be quite thick and isn't structural.
Lewis's Friend said:
Another update on the MX5. Not V6 related yet sadly, but that will be coming soon now I hope.
...
So, was this a massive success? Does much glory accrue to me?
Having driven it, the steering is too heavy for me for road use. I can see how it would be great for a more track focussed car, but for (almost) everyday use it has a little too much heft. This is not helped by the fact that my physique suggests more of a poisoner than a fighter... However, success was had in that the weird pulsing was gone. So definitely an issue with the PAS (if I had to guess from the depths of my ignorance I would say the gating valves for the PAS fluid in the rack are letting by), which I wanted to diagnose before carrying out the V6 swap. So a successful diagnosis, and I've never taken a steering rack apart before so I learned too!
Next step, back to the V6...!
Try it on 185 section front tyres, as were fitted to the car originally. MX5s steer the best on original sized rubber which still has plenty of grip with modern compounds. With much wider front wheels / tyres, manual steering is going to be a chore....
So, was this a massive success? Does much glory accrue to me?
Having driven it, the steering is too heavy for me for road use. I can see how it would be great for a more track focussed car, but for (almost) everyday use it has a little too much heft. This is not helped by the fact that my physique suggests more of a poisoner than a fighter... However, success was had in that the weird pulsing was gone. So definitely an issue with the PAS (if I had to guess from the depths of my ignorance I would say the gating valves for the PAS fluid in the rack are letting by), which I wanted to diagnose before carrying out the V6 swap. So a successful diagnosis, and I've never taken a steering rack apart before so I learned too!
Next step, back to the V6...!
TwoStrokeNut said:
Try it on 185 section front tyres, as were fitted to the car originally. MX5s steer the best on original sized rubber which still has plenty of grip with modern compounds. With much wider front wheels / tyres, manual steering is going to be a chore.
You're quite right, that has probably not helped. I'm happy enough to use the PAS though, as long as it's working ok. I'm happy enough to have identified the problem area, and I've spoken to a rebuild company who I may get to look at it (second hand racks are cheap enough, but I'd be very sad to fit one and find it has a similar issue. Hence debating a rebuild).The perform with smaller wheels at the front is finding staggered wheels and tyres in the right sizes. Particularly as I want a bit more rubber at the back to handle the additional power.
Lewis's Friend said:
You're quite right, that has probably not helped. I'm happy enough to use the PAS though, as long as it's working ok. I'm happy enough to have identified the problem area, and I've spoken to a rebuild company who I may get to look at it (second hand racks are cheap enough, but I'd be very sad to fit one and find it has a similar issue. Hence debating a rebuild).
The perform with smaller wheels at the front is finding staggered wheels and tyres in the right sizes. Particularly as I want a bit more rubber at the back to handle the additional power.
Sure, makes sense. It's a good PAS system anyway and has a lot more feel than any EPAS system I've tried, including the new ND, which is a lovely thing The perform with smaller wheels at the front is finding staggered wheels and tyres in the right sizes. Particularly as I want a bit more rubber at the back to handle the additional power.
Staggered wheels are pretty common, my last five or so cars have had them (lots of Beemers and Porkers, MR2s). It does make it slightly more difficult, particularly in the smaller circumference sizes that are less fashionable now.
WinstonWolf said:
Lewis's Friend said:
WinstonWolf said:
That's bloody genius, I'll pinch that when I replace the rack on the TVR
It got it near enough, but would still need tracking doing!
Lewis's Friend said:
WinstonWolf said:
Lewis's Friend said:
WinstonWolf said:
That's bloody genius, I'll pinch that when I replace the rack on the TVR
It got it near enough, but would still need tracking doing!don't get talked into spending mega bucks...
TwoStrokeNut said:
Greg_D said:
and my local place does the job superbly for £35 - they have a queue down the street.
don't get talked into spending mega bucks...
Yup. You just need to find a good operator with the right machine.don't get talked into spending mega bucks...
they weight the drivers seat in light cars to replicate the real weight distribution. They have the latest hunter gear and fully understand vehicle dynamics. they will do a simple 'back to oem' or change things to suit your requirements. they are every bit as good as the expensive places. the volume of competition cars they deal with is testament to their competence.
I used A-Line recently, they were good. It was £60 for a custom setup rather than £35, but that's still very reasonable for the time involved and end result.
Downsides - they don't take bookings, you just have to show up and wait your turn. That only took about an hour for me on a Friday afternoon, I believe Saturdays are manic.
You need to get to and brave Dudley
Downsides - they don't take bookings, you just have to show up and wait your turn. That only took about an hour for me on a Friday afternoon, I believe Saturdays are manic.
You need to get to and brave Dudley
They’re pretty clear with prices for factory alignments:
http://www.alineyourcar.co.uk/prices
I had a ‘specialist’ adjust which is ‘from’ £60. So I was impressed when I got to the till and it was exactly that.
http://www.alineyourcar.co.uk/prices
I had a ‘specialist’ adjust which is ‘from’ £60. So I was impressed when I got to the till and it was exactly that.
An update at last, that actually relates to a new engine being fitted! As in the actual title of this thread! Real progress...
Although first, in what seems to be just cheekily reusing old pictures but is actually a recent effort, I give you my car up on axle stands being ripped apart again:
IMG_20180915_125155 by Jon Fellows, on Flickr
This is getting it ready to have the engine dropped out of it, so is quite exciting. Although so far I've just been removing all the bits a put on a few months ago... The upside being it all comes apart nice and easily.
I have also started tarting the engine up. After pulling all the anciliary bits off, I drilled and helicoiled a stud, then set about cleaning and wire brushing it for paint. This was a disgusting job, but quite satisfying!
IMG_20180908_135922 by Jon Fellows, on Flickr
It took some time, but hopefully it'll be a good enough surface for paint. I then masked up various bits and gave it a couple of coats of etch primer.
IMG_20180908_143946 by Jon Fellows, on Flickr
That's it for now, but hopefully some more updates soon...
Although first, in what seems to be just cheekily reusing old pictures but is actually a recent effort, I give you my car up on axle stands being ripped apart again:
IMG_20180915_125155 by Jon Fellows, on FlickrThis is getting it ready to have the engine dropped out of it, so is quite exciting. Although so far I've just been removing all the bits a put on a few months ago... The upside being it all comes apart nice and easily.
I have also started tarting the engine up. After pulling all the anciliary bits off, I drilled and helicoiled a stud, then set about cleaning and wire brushing it for paint. This was a disgusting job, but quite satisfying!
IMG_20180908_135922 by Jon Fellows, on FlickrIt took some time, but hopefully it'll be a good enough surface for paint. I then masked up various bits and gave it a couple of coats of etch primer.
IMG_20180908_143946 by Jon Fellows, on FlickrThat's it for now, but hopefully some more updates soon...
A very small update - there should be a more fulsome one soon, as more work has taken place. It's just finding the time to get the pictures together and uploaded...
But for now, some tarting of the engine has taken place. Firstly, three coats of orange paint (which perfectly match the brake calipers - this was what I was hoping for, but did not really expect such a good match). The colour is less red in real life.
IMG_20180917_163914 by Jon Fellows, on Flickr
And I have decided on a nice black crackle finish for the cam covers. I bought some VHT high temp wrinkle paint, and after reading some how to's, painted a takeaway container as a practice. Very happy with how it came out!
IMG_20180919_163453 by Jon Fellows, on Flickr
Just need to do the actual covers to the same standard now!
But for now, some tarting of the engine has taken place. Firstly, three coats of orange paint (which perfectly match the brake calipers - this was what I was hoping for, but did not really expect such a good match). The colour is less red in real life.
IMG_20180917_163914 by Jon Fellows, on FlickrAnd I have decided on a nice black crackle finish for the cam covers. I bought some VHT high temp wrinkle paint, and after reading some how to's, painted a takeaway container as a practice. Very happy with how it came out!
IMG_20180919_163453 by Jon Fellows, on FlickrJust need to do the actual covers to the same standard now!
Snap (sorry about pic its the right way up on my computer!)
Reading this thread with interest
I have just VHT wrinkle painted my rocker covers
Should be getting my rocketeer kit within the next couple of weeks - I have decided not to touch my MX5 and concentrate on the engine until I get the kit
Nice work by the way - looking forward to seeing pictures (and maybe video?) of yours finished
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