Mazda Miata MX5 as a donor ? Is this a good engine, trans, differential ?

[RogerL]

How does the Mazda Miata MX5 1.8L engine compare to the 2.0L Zetec?
Probably potential HP is less; but is it smaller and lighter ?

What is the usual transmission used in a Caterham kit? Is the Miata 5 sp
transmission a good canidate? Is it smaller and ligher than a T5 from
a Ford Mustang V8 ?

Lastly the differential, I have read of problems with the Miata differential.
What is the usual differential and rear end assembly used in a kit?

Just starting to get it together, so many questions. I appreciate everybodys
suggestions. Thanks

[magnusfeuer]

I simply don't know enough (or actually anything) about the 1.8l Mazda engine to make a comparison. You can usually get about 180-200 hp out of a Zetec without going overboard, but the engine is considered a bit heavy. Engine weight is quite a factor in such a light car as the Caterham. Install the engine as far rearward as you possibly can.

The stock gearbox is the Ford T9, which is an old workhorse from the European Ford Sierra from the 80:s. There are good upgrade kits that fixes the drive ratio and sturdies things up. The Caterham 6 speeder is considered the ultimate H-pattern box, but a new one will set you back four grand.

I actually don't have the model number of the diff we are using, but they are also fairly common Ford items. A ZF clutch pack limited slip upgrade is recommended if you plan on doing track events.

I would probably go with a T9 gearbox and the Ford diff, just beacuse they will fit out of the box. Then you can focus on the bell housing and engine mounts.

/Magnus F.

[slomove]

I think a guy in Colorado is just building a Miata powered Caterham (posting on the USA Se7ens List) but the best resource to ask is Keith Tanner of Flying Miata in Grand Junction.

Gert

Edit: found it.....http://www.cardomain.com/ride/636168/12
The name is Skip Cannon

[Doug Liedblad]

Roger

Depending on how much work you want to do, the Zetec and Duratec are both good engines.

The T9 is readily available with lots of choices for gear ratios and options.

All the issues with adaptors, fitting, driveshafts etc have been worked out and are virtually off the shelf items, they fit without effort into a Caterham.

I've been told the Miata engine is heavier than the Zetec but don't know this for a fact.

The Zetec's seem to be fairly bullet proof as Magnus hasn't yet blown up his supercharged one.

Doug

[slomove]

I agree with Doug. I think Skip did that for very specific reasons and because he liked the challenge. But he probably had 10 times the effort and trouble compared to a Zetec. With a Miata install you are basically on your own to work around the problems.

Gert

[Roll a 7]

David L has a Miata diff, I think. Give him a call and he will give you the pros/cons.

[scannon]

Miata Engine & Trans in a Caterham SV

I'm the one using the Miata 1.8 engine and transmission. I chose it because I am very familiar with the Miata drivetrain. The project is coming along nicely.

Probably the most difficult part starts today as the correct Mazda wiring harness arrives and I begin the process of melding the Mazda harness with the SV's harness. The Miata harness will be mainly used for controlling the engine and the SV's harness for the rest of the car. I will be using a Link ECU which is pretty much a plug and play ECU designed for the '96 & '97 Miata. It features electronic boost control, knock sensor and a MAP sensor to control the turbo.

I am using the Ford Sierra diff that came with the car, it has had a Quaiffe LSD installed in it to handle the eventual 250 RWHP. I will probably run without an intercooler at first so the car will start life with about 175 - 185 RWHP.

Pictures of the car are here: http://www.cardomain.com/ride/2175152

Near the bottom of the page is a link to engine installation where you can see what I had to do to the Miata transmission to fit it into the tunnel. The rest of the installation is detailed in the pages following the transmission.

I'm hoping to have it on the road in a month or two.

If you have specific questions beyond what is shown on the pages, post them here or PM me.

Skip

[magnusfeuer]

I have chassis the Caterham chassis connector pinout spec in case you need it.

[scannon]

Magnus,

I would appreciate a copy of the chassis connector pinout. Is it something you can scan and email or do you need to send it via smail?

I started removing the tape and plastic from the Miata main harness tonight. The picture below shows a complete main harness from a '96 Miata. All I have to do is figure out which 40 or 50 wires I need and remove the rest of them. The part with the tape removed represents the section of the harness that resides behind the dash panel, the rest of it goes out into the engine compartment.

Skip

[Elv15]

connector

Hi skip, I have some spare 13 pin connectors if you want to keep the connector that is on the chassis. Send me a pm if you want one.

Cheers,

Tom

[scannon]

Tom,

I appreciate the offer but I'm not sure I will need them. I had planned on bypassing the existing harness and just using the Miata harness for engine control. Maybe I will need them after I get further into the project.

New question:

My assembly manual (says Classic, Roadsport and Superlight on the cover) has the following wiring diagrams:

Main vehicle wiring loom for all standard instrumentation, Rover K-Series varients, 2001 onwards (EU2 and EU3)

Same as above except for stack instrumentation

EU3 1.4, 1.6 and 1.8 K-Series engine loom wiring, Classic and Roadsport varients

EU2 1.8 K-Series engine loom wiring R300, R400 and R500

I have a Roadsport SV car. Am I correct in assuming that the standard instrumentation diagram is good for an SV?

Do both of the engine loom diagrams plug into the chassis loom using the same connectors and pinouts on the chassis loom?

Thanks,

Skip

[magnusfeuer]

Skip. Send me a private message with your email, and I'll mail it over. It is an excel spread sheet.

/Magnus F.