T5 gearbox upgrades or replacement.
T5 gearbox upgrades or replacement.
Author
Discussion

dbv8

Original Poster:

8,676 posts

249 months

Monday 10th August 2009
quotequote all
As im putting more and even more nitrous oxide through my poor 450 Chimaera im wondering what bits going to break first.

Are there any recommendations for the T5 box. I know the 5th gear can be weak but im still in 4th at the drag strip. How strong are the first 4 gears?
I need things to stay in 1 piece at well over 400 lb/ft of torque.
Is it possible to strangthen the T5 or would a new box be required?

I will also be replacing the driveshafts with th 'Raceproved' items.

Are there any other weak points in the drive train i need to look into?

shpub

8,507 posts

301 months

Monday 10th August 2009
quotequote all
Competition Transmission Services... Internal upgrade...

RichardD

3,608 posts

274 months

Monday 10th August 2009
quotequote all
shpub said:
Competition Transmission Services... Internal upgrade...
That'd be this then :-

http://www.gearboxman.co.uk/infot5.html

From a financial point of view would it be any more expensive to wait for such an upgrade until after something had broke scratchchin ?

rev-erend

21,619 posts

313 months

Monday 10th August 2009
quotequote all
Another vote here for CTS .. but no need to worry until it breaks.

dbv8

Original Poster:

8,676 posts

249 months

Monday 10th August 2009
quotequote all
Cheers.
Looks like a plan.
Richard, it would be interesting to see how the close and wide options compare.
Can you try my last run out with both sets of gears please,
ie
wide
1st = 2.915
2nd = 1.932
3rd = 1.323
4th = 1
5th = 0.8

close
1st = 2.527
2nd = 1.675
3rd = same
4th = same
5th = 0.87

rev-erend

21,619 posts

313 months

Monday 10th August 2009
quotequote all
There is a gear calculator on the CTS site..

RichardD

3,608 posts

274 months

Monday 10th August 2009
quotequote all
rev-erend said:
There is a gear calculator on the CTS site..
Derek was referring to the model I have of his car in some software (Cartest 2000) and differences to a 1/4 mile time nerd

It seemed that such a tall first gear would require serious clutch abuse in first, especially with Micky Thompson drag radials!

rev-erend

21,619 posts

313 months

Monday 10th August 2009
quotequote all
Cartest - used it myself.. nice piece of kit smile

FOT Fast

180 posts

251 months

Wednesday 12th August 2009
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I don't know how much the Gearboxman upgrade is but with the Pound improving against the Dollar maybe you should have a look at:

http://www.gforcetransmissions.com/tran_gt-5.asp

This may also help:

http://www.fordmuscle.com/archives/2005/12/T5Rebui...

dbv8

Original Poster:

8,676 posts

249 months

Wednesday 12th August 2009
quotequote all
The conversion this side of the pond is £895.
Ive emailed the states to see how they compare.
Interesting the ratios are basically the same in the first 4 gears but have a long overdrive of 0.59:1.
I know i would never use 5th on a drag strip or race track so i think this would be beneficial to motorway cruising and a theoretical top speed of over 200 mph.
Maybe they could do a 0.75:1 or thereabouts would be better.

350Matt

3,895 posts

308 months

Wednesday 12th August 2009
quotequote all
A simple mod to do on the T5 is make sure you use a 75W-90 or 75W-80 oil such as castrol SMX-S.
5th gear fails as there's no bearing underneath it , just steel running on steel with an oil film. Use a stronger film strength oil and the box will last longer

Matt

S6 Devil

3,556 posts

262 months

Wednesday 12th August 2009
quotequote all
There was a guy selling a T5 gearbox with Quaife internals on ebay. I contacted him and he had sold the one advertised but had another to sell. If you want his phone number give me a PM.

Edited by S6 Devil on Wednesday 12th August 15:17

Graham

16,381 posts

313 months

Wednesday 12th August 2009
quotequote all
We've been looking at a conversion using the elite 6 speed sequential gearbox. so far we've had it mated to a john eales modified t5 bellhousing in a chimaera chassis behind the rv8... it all seems to go in fairly well. with some minor work to get the shifter in the right place..

We're using the rlite box in our Sagaris racer and Tim hood is now running one in his LS3 sagaris racer as well..

If your interested in talking about fitting one drop me a line.. the box can be built with either straight cut or helical gears to keep the noise down in a road car, although currently still dog engagement rather than synchro.

The nice bit about the elite is the drop gears, so you can quickly speed up or slow the box down.

Cheers

Graham



dbv8

Original Poster:

8,676 posts

249 months

Thursday 13th August 2009
quotequote all
Graham said:
We've been looking at a conversion using the elite 6 speed sequential gearbox. so far we've had it mated to a john eales modified t5 bellhousing in a chimaera chassis behind the rv8... it all seems to go in fairly well. with some minor work to get the shifter in the right place..

We're using the rlite box in our Sagaris racer and Tim hood is now running one in his LS3 sagaris racer as well..

If your interested in talking about fitting one drop me a line.. the box can be built with either straight cut or helical gears to keep the noise down in a road car, although currently still dog engagement rather than synchro.

The nice bit about the elite is the drop gears, so you can quickly speed up or slow the box down.

Cheers

Graham
Now this sounds really interesting but also very expensive.
Can you give me a ballpark figure for parts?

scotty_d

6,795 posts

223 months

Sunday 27th January 2013
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How did you get on with a T5 upgrade Derek?

I am at the point with my Box out as 2nd and 5th are going in the Cerb so i will beef it up as i will be getting a re-map very soon after a few upgrades so will be a good bit over the box's power rating.

I have looked at both the uk kit and the one on over the pond just looking for feed back.

Cheers Scotty

TVR_owner

3,349 posts

220 months

Sunday 27th January 2013
quotequote all
I bought a brand new CR T5 from CTS - with all the upgrades available. It was subsequently upgraded due to necessity after less than 10 hours race use (behind a V6 producing less power and torque than your V8 Derek smile ). Readman Racing did the work for me and there were some easy upgrades that strengthed the box. They also fitted a hurst quickshift at the time. Must say a much nicer after upgrade.


dbv8

Original Poster:

8,676 posts

249 months

Sunday 27th January 2013
quotequote all
Yeah i had mine rebuilt with some upgrades by John at Readmans also.
There was a small mix up. John replaced the tail with a direct gearstick option rather than the remote type linkage we all have. I didnt realize i would need to make up a new gearbox mounting and to modify the gearstick itself to sit back in its original position. I didnt have the time or materials so took the box straight back and John replaced the original tail. I had the box back in and the car was on the way to the drag strip the next day.

Johns a straight up guy and agreed a price before hand. When he stripped my box he found my gearset was on its last legs (cant think why rolleyes). Another customer had brought a Sag box in for a close ratio gearset so he fitted the old set from that to mine at no extra cost. Apparently the Sag only had 8k on it.
The box works as new now. Only problem is a very slight leak at the original tail seal on the prop.

scotty_d

6,795 posts

223 months

Sunday 27th January 2013
quotequote all
http://www.gearboxman.co.uk/infot5.html

is this the kit you guy went with?

What power will this handle does any on know?

dbv8

Original Poster:

8,676 posts

249 months

Sunday 27th January 2013
quotequote all
scotty_d said:
http://www.gearboxman.co.uk/infot5.html

is this the kit you guy went with?

What power will this handle does any on know?
No. Just had a rebuild at Readman's. Much cheaper.

Steve Heath has run a LOT of power through a T5 in his wedge racer IIRC.
They can handle more power and torque than you may expect. Ive had over 500lb/ft through mine plenty of times

scotty_d

6,795 posts

223 months

Sunday 27th January 2013
quotequote all
dbv8 said:
No. Just had a rebuild at Readman's. Much cheaper.

Steve Heath has run a LOT of power through a T5 in his wedge racer IIRC.
They can handle more power and torque than you may expect. Ive had over 500lb/ft through mine plenty of times
Do you have a contact? Is he local to you as I will have to post mine no doubt.