Hi,<o:p></o:p>
I am new to the forum and very new to the MX5 (I am collecting my first MX5 later this week) I am very much looking forward to driving the 5 but it is down on performance from what I have been used to driving but a change in life means a change in car, I am buying a 2000 1840cc model and have read quite a bit about fitting a turbo which I am thinking about but the kits I have seen seem expensive £1500+ but I have found this on ebay and would like to know your thoughts on it, I am not mechanically minded so dont know if it would need any extra items or it is just a case of buying and having it fitted.<o:p></o:p>
<o:p> kit is on ebay http://cgi.ebay.com/ebaymotors/JDMS-94-02-MIATA-MX5-1-8L-T25-T28-TURBO-KIT-275HP-/140336121641?pt=Motors_Car_Truck_Parts_Accessories&hash=item20acaf4729</o:p>
Any help would be great.<o:p></o:p>
Thanks,<o:p></o:p>
Sean<o:p></o:p>
Sadly ebay is blocked from this PC, so I can’t see your kit.
I bought a “complete” turbo kit in “good condition” second hand for £500. Some parts were missing, some parts were damaged, some parts needed tweaking to work better and the wastegate was set wrong. Fortunately I’ve designed turbo installations as part of my job, so knocking up the new bits and bunging it in my car was a doddle. Someone else could have had a frustrating couple of weekends fitting it before getting to the end result - which is a turbo installation that has been reliable for the best part of 4 years.
However. I’m not convinced that as a road car the MX5 is actually any more fun now it’s faster. Some of the charm was thrashing the car without the constant worry of speeding (or suddenly losing traction in third gear in the wet). I love my car as it is, but I loved it before too, and its still a long way from being the fastest car I’ve had.
Have a good hard drive in your new car, then decide whether it really needs to be faster.
Well ebay kits are cheap for a reason they are usually made of sub standard materials and often missing important parts that you need to make the whole thing work. The one in your link has a stainless manifold which will more than likely crack after a few heat cycles (turbos get very hot I’m sure you’re aware). Also I can see the top elbow for the downpipe but not the rest of it so you’d have to have that fabricated which could be costly. The picture does not show any means of controlling timing either which you need to retard across the board in the most simplistic form to keep the engine safe. It does have a rising rate fuel pressure regulator, but that is not the best way of controlling fuelling. There are also no bigger injectors included. You could run on stock injectors to about 5/6 psi but not beyond that as they cannot supply enough fuel.
read all the links on this page:-
http://miataturbo.wikidot.com/
That will give you a good start on what you need to know. Best bet for a turbo kit is either bell engineering or flyin miata in the states. They both make good quality kits and will supply everything you need to do a successful build.
Stainless manifolds can be reliable if you use a seperate turbo support bracket. Turbos are heavy lumps and expecting thin walled tube at 700 degrees to be strong enough is bound to end up with a few failures.
Retarding the ignition and using an AFPR can work just fine, as long as you don’t go mad with the boost. It’s not the best solution, but it is the cheapest, and it works. Mine has been fine for years.
When thing are cheap you just have to think about them a bit harder. Would 155bhp be enough to make you happy? If so then 6psi of boost is plenty. You can always add spark and fuel control later to increase power, if you need to and can afford it.
I’ve not experienced an FI 5 but suspect it can be a curate’s egg…good in parts
I have a 2.5 sport with the VVT engine and although there are times when a bit more low down grunt would be great, the charactertistics of the car appeal to me as they are
ie when you are pulling 4 - 6k it really gets on cam and is fast enough. the driving challenge is to keep it there…or anticipate road conditions so that you can execute yr move in the peak rev zone.
I’m not anti-turbo having owned various rover vitesses (great car had they paid any attention to building it properly) and a Saab 900 turbo
I’ve fitted and induction kit (great noise - not sure it does anything for bhp) and will be adding some sort of cold air feed at some point but will leave it at that I think
until Steve at 5-speed gets his demo car on the road which he’s promised me a try out in…might change my mind then
…and I’m not talking christine here…that thing’s just mental
If you do get a turbo and decide to get someone to fit it then be very careful who you get to do it. I’ve been to this garage before and I wouldn’t go there again!