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MX5 Transmission
MakeEverything - 24/5/16 at 09:12 AM

Hi all, Its been a while!

I have had a search around, and was wondering who has fitted what engine to the MX5 transmission (5spd Mk1).

Long story short, im looking at an MX5, and was wondering what the easiest way of getting maximum power into it was. I do really fancy a V6 (though for some reason, really do fancy the cosworth 2.9 ford unit). Happy to look at turbocharging etc, but not sure at this stage that the original engine can take much.

Have also dropped Claire an email too, so waiting for her expert advice.


WallerZero - 24/5/16 at 09:26 AM

I'm in the process of following Claire's KL V6 swap. Unfortunately Claire has been very busy so ended up doing the plates and mounts myself (some bits drawings and manufactured at various places), just took a bit of time and thought.

Having not actually driven it yet its hard to say how good but on bike throttle bodies running similar to Claire's and others, I'd expect around the 200bhp mark. Personally the V6 sold me more than any FI options but the KL is growing rare and parts are getting expensive, even more so if from America

Edit to add: The mx5 engine has been proven to take up to 250bhp on stock internals, however from briefly looking around, upgrading these are cheaper than some alternatives if you desire more power

[Edited on 24/5/16 by WallerZero]


theconrodkid - 24/5/16 at 09:58 AM

i have been thinking of going the V6 route,research shows the Jag V6 engine can be had for pennies so i cant see it being any harder to fit than the (rare) Mazda lump.....just my 2p worth


MakeEverything - 24/5/16 at 10:47 AM

quote:
Originally posted by theconrodkid
i have been thinking of going the V6 route,research shows the Jag V6 engine can be had for pennies so i cant see it being any harder to fit than the (rare) Mazda lump.....just my 2p worth


Thanks, isnt the jag engine just a ford duratec V6?

The old Cossy V6 can be picked up for a few hundred quid, and man enough to play with in terms of forced induction or the nitrous kit that i have had in my garage for a number of years....


MakeEverything - 24/5/16 at 10:49 AM

quote:
Originally posted by WallerZero
I'm in the process of following Claire's KL V6 swap. Unfortunately Claire has been very busy so ended up doing the plates and mounts myself (some bits drawings and manufactured at various places), just took a bit of time and thought.

Having not actually driven it yet its hard to say how good but on bike throttle bodies running similar to Claire's and others, I'd expect around the 200bhp mark. Personally the V6 sold me more than any FI options but the KL is growing rare and parts are getting expensive, even more so if from America

Edit to add: The mx5 engine has been proven to take up to 250bhp on stock internals, however from briefly looking around, upgrading these are cheaper than some alternatives if you desire more power

[Edited on 24/5/16 by WallerZero]


Its more the torque addiction i have, having now got rid of my SL500. Do you have a bellhousing drawing for the MX5 bellhousing please? Any info would get me started.

The other consideration is clutch, so i really wanted to try something that worked pretty much straight off the bat rather than get into lengthy design, trial, fit, remove, re-design, trial, fit etc etc.

The other question i have, is wether there are differences between the 5 speed and 6 speed in terms of bolt patterns etc. The extra gear would be handy.

[Edited on 24-5-16, by MakeEverything]


Charlie C - 24/5/16 at 11:49 AM

Hi

Its worth having a look at this book How to build a high performance MX5 it will answer most of your questions.

Regards
Charlie


MakeEverything - 24/5/16 at 11:53 AM

quote:
Originally posted by Charlie C
Hi

Its worth having a look at this book How to build a high performance MX5 it will answer most of your questions.

Regards
Charlie


Legend, thankyou.


MakeEverything - 24/5/16 at 12:34 PM

quote:
Originally posted by Charlie C
Hi

Its worth having a look at this book How to build a high performance MX5 it will answer most of your questions.

Regards
Charlie


And now youve got me considering V8.


mcerd1 - 24/5/16 at 01:39 PM

A couple of things to remember with the old cossie v6 (boa or bob) is just how big and heavy the cologne engines are and how much of a pain they can be to service....



[Edited on 24/5/2016 by mcerd1]


theconrodkid - 24/5/16 at 02:38 PM

Thanks, isnt the jag engine just a ford duratec V6?

The old Cossy V6 can be picked up for a few hundred quid, and man enough to play with in terms of forced induction or the nitrous kit that i have had in my garage for a number of years....

based on the Fraud unit but there are piles of them on every street corner going by the prices on fleabay where the ford based ones are a bit rarer,as for the BOB,they are as others have mentiond,a heavy old lump of iron.


MakeEverything - 24/5/16 at 02:43 PM

quote:
Originally posted by theconrodkid
,a heavy old lump of iron.


Nope, its an ali block.

The cologne 2.8 and 2.9 were aluminium, and the Essex 3.0 was cast iron.

ETA: ive lifted the 2.9 12V by hand before now.



[Edited on 24-5-16, by MakeEverything]


mcerd1 - 24/5/16 at 03:17 PM

quote:
Originally posted by MakeEverything
quote:
Originally posted by theconrodkid
,a heavy old lump of iron.


Nope, its an ali block.

The cologne 2.8 and 2.9 were aluminium, and the Essex 3.0 was cast iron.

ETA: ive lifted the 2.9 12V by hand before now.

you must be strong then !
most folk seem to estimate its 170 to 200kg (I assume built up with all the bits on it)
the same sorth of estimates make a pinto around 135kg

https://en.wikipedia.org/wiki/Ford_Cologne_V6_engine

you are right that they are nothing to do with any of the Essex V6's - but they are definitely an iron block
I had a 2.9 XR4x4i, it was definatly a massive lump of iron under the bonnet (also had/got some 3.0 Essex engines too, totaly different but just as heavy...)

The only alloy blocked ford V6's I know of are either the newer american stuff or are the duratec/mondeo/mazda based ones like the Jag3.0 etc...

[Edited on 24/5/2016 by mcerd1]

[Edited on 24/5/2016 by mcerd1]


prawnabie - 24/5/16 at 03:30 PM

I've got a BOB in the garage at the moment and judging by the weight of the thing its got to be close to 200kg!


MakeEverything - 24/5/16 at 03:54 PM

quote:
Originally posted by prawnabie
I've got a BOB in the garage at the moment and judging by the weight of the thing its got to be close to 200kg!


Wanna sell it?

I couldnt shift the 24V but managed to get the 12V up and onto a skate about 100mm off the ground. Made some funny noises doing it too.


Beardy - 27/5/16 at 03:15 PM

There are several threads here discussing the weight and size advantage of KL V6 over these other option. I was all set to go to Claire but she's been busy and being in the US I didn't want to be out on a limb (especially given the language problems). I have decided to go down the route of more torque via a large 4 cylinder and will be fitting a 2.4 Ecotec LE5 (bigger capacity variant of the Z22SE/VX220 lump) to a MX5 box using the Ecotecmiata conversion from Canada. I don't have it yet.
I want to go Bike carbs or ITBS from DanST, but also currently looking at what rolling roads exist round here (near Portland, OR)to see if it makes a difference.

Beardy
(WA state)
PS if you need something from over here I may be able to help.
PPS building Exomotive Exocet based on a 99 MX5 and will try to keep it as light as possible, so think `Seven' but with more crash protection.


Beardy - 11/2/19 at 03:54 AM

Note that Rocketeer ltd in Farnham sell a conversion to mate the Duratec V6 3.0 (jaguar etc.) to the NA/NB 5/6 speed box