Cosworth T5 box with TVR bellhousing clutch release

StevenC · Post by **StevenC** » Wed Feb 22, 2012 8:00 pm

Hi all,

I have a T5 Cosworth gearbox and TVR bellhousing and clutch release. With the intention to fit to a RV8 engine.

The TVR bellhousing circular hole does not quite fit over gearbox bearing retainer on front of T5 box (about 2mm out).

Before I start machining or changing parts. Does anyone else have this combo fitted in car.

Any advice you can offer on your own experience on how you fitted together and got working well would be much appreciated.

Does a TVR T5 box bearing retainer fit on same bolt circle of Cosworth T5 ?

Do all the clutch release parts from TVR work with Cosworth T5 box ?

Also the speedo connection is missing and I wondered about the best way to plug (core plug ?)

Thanks,
Steven.

richardpope50 · Post by **richardpope50** » Fri Feb 24, 2012 5:19 pm

I have a TVR bellhousing and a World Class T5 off a TVR and so obviously it all fits. I'm surprised the Cosworth T5 is different (apart from the gear lever mounting) but my gearbox and bell housing are all off the car at the moment so I can easily measure / photo anything if this helps.

r2d2hp · Post by **r2d2hp** » Fri Feb 24, 2012 5:49 pm

The TVR box is different in a number of ways. If I remember correctly the Input/Output shaft, release bearing and the retainer are all different.

I had a similar problem with a TVR box, had it converted by CTS so I could fit it into my Capri.

StevenC · Post by **StevenC** » Sat Feb 25, 2012 2:59 pm

Thanks guys.

I hope there may be a few others who have teamed together TVR bellhousing and clutch release with Cosworth T5 gearbox as the advice is all very welcome.

Here is a bit more information since my original post.

The Cosworth T5 gearbox bearing retainer flange diameter is 121mm. The corresponding hole in TVR bellhousing is about 117mm.

So for these to fit - one will need to be made smaller or larger respectively. Both seem to have scope to do this without interferring with bolt circle on box or pivot on bellhousing.

The Cosworth T5 bearing retainer shaft OD is about 31.5mm.

The TVR clutch release bearing and carrier do fit. I cannot remember the exact ID dimension I took - will post later.

Any further advice before I start any modifications would be much appreciated.

thanks,
Steven

StevenC · Post by **StevenC** » Wed Feb 29, 2012 1:14 pm

I now know my TVR clutch release bearing is not suitable for Cosworth input bearing retainer.

I am therefore thinking whether I can change the Cosworth input bearing retainer for a TVR one.

IF this is possible then it should allow me to use my existing TVR bellhousing and TVR CRB should work.

Does anybody have access to a TVR T5 box that they let me know the bolt PCD for input bearing retainer ?

Also any ideas where to get a replacement ?

thanks,

richardpope50 · Post by **richardpope50** » Wed Feb 29, 2012 2:15 pm

Mine is off the car on a stand at the moment so ...

100mm PCD would seem to it. I measured it in a difficult place as it's on a stand so don't drill on these measurements. It could be 102mm.

Good enough?

StevenC · Post by **StevenC** » Wed Feb 29, 2012 8:33 pm

Thanks Richard,

I will double check the measurements of my Cosworth box tomorrow.

StevenC · Post by **StevenC** » Thu Mar 01, 2012 1:21 pm

Right, it appears th PCD on Cosworth box is also 100mm so should be able to fit TVR input bearing retainer if needbe.

Or, I may be able to keep the existing bearing retainer.

The Cosworth bearing retainer shaft OD is 31.5mm.

The TVR CRB carrier ID is 33mm.

Does this sound ok ?

Richard - do you know OD of TVR bearing retainer shaft ?

r2d2hp · Post by **r2d2hp** » Thu Mar 01, 2012 2:16 pm

Is the input shaft the same length, seem to recall there was something else I had to change but can not recall what it was

StevenC · Post by **StevenC** » Thu Mar 01, 2012 10:51 pm

Good point. I am not sure.

I am relying on Richard at the moment as he has his TVR box out of the car.

Richard, looks like a few more measurements would be handy if you can help

Input shaft length ?
OD and length of input bearing tube where CRB sits ?

Sorry to be a pain, but I cannot this info on the web. Hopefully our efforts to take measurements will help others in the future.

much appreciated.

richardpope50 · Post by **richardpope50** » Sat Mar 03, 2012 7:15 pm

Input shaft length = 155mm to edge of bearing.
Bellhousing circular hole = 118.78mm

input shaft bearing tube as picture below:
Outside /dia = 54.81mm
Inside dia = 34.8mm
length of tube = 58.36mm

How my CRB all fits

My speedo blanked off

Hope this all helps.

r2d2hp · Post by **r2d2hp** » Sat Mar 03, 2012 7:26 pm

Hi Richard, can you measure the the end of the shaft that goes into the spigot bearing as well please. Recall having to get one machined

richardpope50 · Post by **richardpope50** » Sun Mar 04, 2012 10:11 am

Not as easy as the box is on an engine stand and that's down a tube. However I'll come back on this.

richardpope50 · Post by **richardpope50** » Sun Mar 04, 2012 1:36 pm

OK,

I/dia of spigot bearing is 15.1mm thus shaft is 15mm (I assume as it is down the engine stand tube so difficult to measure).

I revise shaft length to 156mm with the last 27mm being the 15mm dia for spigot. Note there is a chamfer from 15m section to splined section so the 27mm is more or less to start of the chamfer up to spline section. Hope that makes sense.

HTH.

Devonrod · Post by **Devonrod** » Sat Aug 29, 2015 7:29 pm

I found this old Topic very useful as I am mating a T5 Cosworth box to a TVR Chimaera bell housing, sure enough the front bearing retainer needs turning down to fit the bell housing, after a quick look at the Chimaera bell housing it is about roughly 5 or 6mm shorter than the LT77 bell housing, likewise the TVR bearing carrier slots for the arm are roughly 5 or 6mm nearer to the bearing than the LT77 one, the worst thing is the TVR bearing carrier is like a sausage up an alley ! although it will work its not right !