Best clutch size for a Cosworth conversion

[ginsambo]

Anybody know the diameter of the Sierra 2.0 dohc MT75 clutch??

I know the Transit Mk5 MT75 2.5Di Clutch diameter is about 240mm with a friction plate width of 45mm

I've got a SVO Transit with a 2.9 Efi in it but its still intact at the mo. so I'm being lazy and asking!! I'm actually now thinking of selling it on after copying the engine mounts and using a 2.0 Dohc MT75 instead!!


- How do the two clutches (2.0 DOHC MT75 Sierra one & SVO Transit MT75 2.9 EFI) compare



- I'm considering the Sierra 2.0 DOHC MT75 car gearbox for a 24v Transit project with a hole cut out for the gearstick, really because its simpler and also more sustainable in the long run regarding spare flywheels etc.

I've also considered Tremec boxes (TVR etc.) and 24v Cossy Tremec bellhousings but for £700 odd secondhand I think I'd rather chew through a few MT75's if I do any at all first as £700 represents around 14 Quantity MT75 boxes!!

...But I'm wondering what is best for a HEAVY higher powered vehicle as I know the US Pickups and obviously lorries have large clutches -



My Transit is a 190 Pickup and NOT a VAN and I wanna keep my 3500kg GVW and get the Cossy up to 250Bhp+ I don't think I'II be travelling with a full train weight with it as I'II use the deisel for total abuse but I will be riding 3500kg sometimes.

Obviously Fords made the SVO 2.9 Efi Transit monster flywheel for a reason

- Will I just wear out a smaller clutch faster or will it really not work so well with a heavier vehicle??

[Luke]

how are you gonna bolt the DOHC MT75 to the V6 engine

[ginsambo]

Doesn't it just bolt straight up? I thought the bolts patterns were the same on the cologne block and these boxes are advertised on Ebay as the 'Ideal' Cologne manual conversion?

Thing is I've got a MT75 that came with one of my cossie lumps.
It's in storage so I am being a lazy arse again. I assumed it was a 2.0 DOHC MT75.

So is this a custom granada Manual box?? Yeah I know I'm spoilt but I've been planning this for two years!! I have my suspicions that it is knackered anyway, probably that particular engine too as the input shaft rotates on a 20 degree bend / wobble.

How big was the clutch on your SVO 2.9 Transit donor..roughly??

[Luke]

right............. no it doesnt bolt strait up you need to not only change the front half of the box but you'd need to change the i/p shaft too as its longer on the V6 than the dohc

i can measure my clutch up exactly if you want as i've got a spare now might even be the same as a Di one

[Luke]

so you have an SVO transit 2.9 then you'l have the adapterplate

[ginsambo]

That's what I was originally planning with the donor SVO. Only thought was that I don't like the gearstick being so far forward and I thought if I ever knackered a flywheel....

Other problem is the van is so nice I haven't got the heart to lay into it. Was thinking about getting stuck into it after putting it through an MOT, then copying the bits I need at an engineers, then putting it all back together and flogging it with 12 mtn ticket..it owes me a bit more than scrap value and its all been waxoiled from new. But then thinking about the engineering costs...

Thing that unsticks that plan is the flywheel... Everything else is more or less directly copyable and an for an undriveable MK3 even in good nick I reckon I'II be looking at scrap value.

Any ideas?? I really need to get some cash back from the Van. I would keep it but its a Van, and a van with IFS and 14" wheels.

I've got no experience of any MT75 other than Transit ones - so the car MT75 box I have that fits the cossy is a slightly customized lump you reckon? In which case all the custom V6 Car MT75 boxes I could get old of that would fit the bill are gonna be knackered by generations of boy racers then aren't they?

So basically you are telling me that everything is as rare as everything else

I'II have to have another think and get a better idea of it....you reckon the SVO clutch was about same size as the standard 2.5Di one friction wise?

[Luke]

if i remember i'll measure the clutch tomorrow - it's at work

why not swap the engine in the van for a Di that way it will be more valuable and you get all the bits

[ginsambo]

Looked into it a bit.. Thanks for the advice

Deisel Scorpio box, Sierra bellhousing, special separation tools, Escort Cosworth clutch....bit more too it than I'd hoped and for all that money I could almost get another SVO Flywheel made up!

Better off with the SVO setup I think with the relatively minor downpipe problems. Although as I do have the bellhousing already.....

Diesel conversion is genius idea. I've got two spare looms and a 2.5Di I could knock together from two if I change the cam (Cam snapped at Sprocket). I'II look into the price of similar vans right now. As all the small things do add up, I am thinking I may be better scrapping it and selling the 2.9 EFi separately as its genuine low mileage (About 28-30k as I remember but a bit rusty). 6 new tyres but 14" and a low ratio six stud twin wheel axle to boot..but 14"! Seems such a waste I guess that I'd rather someone used it, especially as I've run Mk5's in far worse condition. I could never have a van, I'd never get to sleep at night worrying about all that panelwork....and all that paint .

I am dreaming about mounting the cossy a bit further back somehow, I don't know how much a 24V cossie weighs compared to a 2.5Di but any vehicle which has the engine mounted forward of the shocks..understeer is an understatement and this is a pickup we are talking about, not a van! Still I only really want it for straight line speed so I'II keep dreaming I think!

I'II get stuck into the cossies and explore the possibilities. Also a bit worried about spare SVO starter motors, although I guess starter motor reconditioning isn't the end of the world.

Well I should finally make a decision - I'II never get anything talking about it! First thing to try is the '94 era 45 degrees chassis mount brackets, spotted a couple of different types and one van has the same boltholes I swear.

[MinorMatt]

what year van is it mate?

[OxtonyxO]

the cossy is a lot lighter than the di
also you will not be able to mount the 24v farther back without loosing the heater and cuting the bulk head

[andykay]

Just buy this already to go in

http://cgi.ebay.co.uk/Ford-2-9-V6-coswo ... dZViewItem

Andy.

[ginsambo]

Just buy this already to go in

http://cgi.ebay.co.uk/Ford-2-9-V6-coswo ... dZViewItem

Andy.

That listings got a type 9 doesn't it or does it just look like one cause its painted black?? I'II chew through that!!

Right, managed to dig these out from the garage. Here are the gearboxes and flywheels I've got, excluding the SVO Transit 2.9EFI V6 one which is still on the van:







What does anybody make of this gearbox, it has to be a hybrid MT75 doesn't it?? Its got a long Input shaft.

Is this a Sierra Flywheel, or an auto Granny Scorpio one, I can't remember what they look like? - its big and wierd like the SVO flywheel but hasn't got the extra width of the actual plate. I'II count the teeth, may even have the same ring gear.

Except for the offset, the clutches are the same size diameter and friction area (Sierra and 2.5Di Transit, so I assume the SVO one is the same size too, although possibly may be offset different???).

Matt: The SVO van is a hi top twin wheel 1990 Mk3 SVO Factory 2.9EFI, Not a 2.8, Transit 190 with front leaf springs, the Mk1-3 Style chassis and the 14" wheeled axles.

I reckon even if I put a diesel in it after the cost of a class 5 MOT ticket price I would be looking at the same for breaking it and weighing it in. If it were a mondeo I couldn't care less but being a Mk3 Transit that is still in better nick than 99% of the Mk5's out there I am loathe to butcher it. I bought it for the cossy conversion still in ticket and have hardly driven it, don't really know why I am so attached to the thing...but I am. Maybe I will diesel-fi it. Definately want the bits out of it and its a useful mobile shed too. I may copy the SVO Tag and make my own so I can present a pic of it to the insurance company as a joke, see if anyone believes me: 'Factory Ford 24V Cosworth 3500kg GVW Transit 190 Pickup'

I already have two cossy engines, complete with ECu's and looms, one is OK, the other is asociated with the possibly wonky hybrid box so I donno?? I ws gonna do one, see how the Mpg and power works out vs insurance (£600 quoted so far), then maybe do another, or keep a setup as a spare. Me likes collecting things!!!

The hybrid box would fit if I maybe sortened the cradle/control arm, maybe not bother. Overall length is exactly the same as a Transit MT75 box minus the conversion plate (Roughly 10mm). Ford Mechano!! So in other words, its shorter than the Transit MT75 overall by 10mm - spot on! Also Gearbox subframe mount holes are exactly the same as the transit.

Its an easy alternative to the Transit SVO Flywheel and Box? But I reckon the input shaft is knackered as it appears to rotate non-centrally, even when you hold it down to acount for play in the bearing, it still seems slightly bent to me!!

Any views on this Hybrid MT75?? Is it a Hybrid?? Hope these comparision pics are useful.

[OxtonyxO]

ok

in your 2.9 svo van the gearbox will be a standard transit mt75 box , not an svo box there will be an adaptor plate fitted
just whip the plate out and have it copied