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Moaning twin spark RWD?

Unexpected question, I'm sure, but I'm working hard to convince myself that I will build a Lotus 7 clone (the book by Chris Gibbs is already purchased, for starters.)

I know a source for brand newvTwin Spark engines that has 1.6, and 1.8, and I'd like to use one of those, obviously, instead of a pinto-engine..Could anyone tell me which gearbox/diff I could use for that?

Of course, I could (and likely will) base it on a MX5 instead of a Sierra, I've looked around for sequential gearboxes which included a reverse gear, but some that found cost over €10000, which rather defeats the purpose of building a car myself. (A 2nd hand mx5 costs up to €4000)

I'm rsther dmitten with the 1.8, since I've had one in a 156, very nice performance, and very nice raspy exhaust note (I've noticed othermakers' 1.8—engines having the same exhaust note. The GT I've owned for a short while had a JTS 2.0 which nicely had more torque at low revs, also the car had fabulously well weighted controls, which made it an absolute joy to drive, until I lost my job and had to sell it.... but sound-wise, I prefer the 1.8.
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VO2Max
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Why don't you get a 1.8 twinspark engine and then mate it with a Selespeed sequential gearbox?
 
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Why not just use an MX5 engine which comes with a gearbox already attached? Don't go made with the silencers and it'll sound nice and raspy. BTW, rusty grey import Eunos roadsters are dirt cheap over here.
 
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Originally Posted by VO2Max View Post
Why don't you get a 1.8 twinspark engine and then mate it with a Selespeed sequential gearbox?
The Selespeed gearbox is FWD only unfortunately, a Lotus 7 replica would need a RWD gearbox instead.

MX5 gearbox, prop & rear diff with an adaptor plate or a custom bell-housing is probably the way forward.
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Selespeed isn't sequential. It's a standard box with a robot doing the changes.

105 series are often TS converted
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It goes up and down in sequence, why isn't that sequential?
 
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Why not base the whole thing on a rusty 75?
 
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It goes up and down in sequence, why isn't that sequential?
A sequential box can only go through the gears in sequence, the Selespeed can go from 5th to 1st for example without going down through all the gears. It is just a manual box with the actuator controlling the clutch operation and movement of the selectors.
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Why not base the whole thing on a rusty 75?

Bdcause I have a PDF with an update of the Gibbs book, to use an MX5 fir a donor instead of a Sierra (which is getting quite rare what with it being such a popular kitcar donor) also, to be able to get it road registered (iirc I've read that the Dutch IKS (Individual Test - Special) tests for emmissions like it's a new car,regardless of engine age) so a 75 engined car might not pass. Which would be a pity, because a 75-engined Seven would be molto freddo. But by now some may have succumbed to oil-consumption problems. I've seen the odd 75 leaving behind a nasty trail of oil smoke.

I've also been fantasizing about making a mid engined car, with a GRP monocoque, like a GTM Libra, but designed around the twinspark engine. Could be that the TS won't pass current emissions either (Alfa did replace the engines in the current crop of cars), one problem with cars like that is the gear change which can be difficult, vague etc. So I thought, hey, Selespeed! And then I thought, oh wait, CAN bus , to implement the Selespeed system I'd have to implement a whole CAN bus in the project but there's so much that's connected to CAN bus which I have no plans to implement in my own project, namely just about everything electrically operated.

The first Selespeeds were made without Can, but I think I've read that they can be problematic, so that option has lost some of its desirability...

BTW, theese are sites about the car that inspired me: Links to webpages interesting for GTM Libra owners and Bertram bouwt een GTM Libra

Last edited by DutchMarco; 15-10-12 at 08:17. Reason: add some links
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A sequential box can only go through the gears in sequence, the Selespeed can go from 5th to 1st for example without going down through all the gears. It is just a manual box with the actuator controlling the clutch operation and movement of the selectors.
I know, I had one! And it never skipped a beat in 90,000 miles!

Ah, I see what you mean. So actually, the Selespeed is better than a sequential box. I used to love the way the box would do a quick change from 5th to 2nd of ts own accord, when coming fast into a big RAB, braking firmly then hitting the gas to pull out of it.
 
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Sequential boxes are good at doing what they do on race cars and bike-engined cars etc.. But not so good on road cars. Selespeed is better on a road car for sure, as long as you have a reliable one like your old one was.
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