20 replies to this topic

[Bumblebee]

Hi guys, It looks like 1st gear synchro is on its way out ( crushes when going onto first gear) Can anyone recommend a good company to use? Preferably a company that offers an exchange box? Having a bit of a nightmare trying to find a company Thanks � Sent from my E5823 using Tapatalk

[chickendippers]

"Halifax Gearbox n Clutch Centre" seem to be very well recommended, particularly with the M32 peeps. Failing that give RnD a call and see if Dan can do it, if not where he can recommend  

[D-DAWG83]

Would it not be easier to try and find a lower mileage box? Must be plenty around

[siztenboots]

could buy a DZ gearbox for a 3.95 final drive

[mbes2]

Would it not be easier to try and find a lower mileage box? Must be plenty around

 

Not normally the case with a tubby box, I had mine rebuilt with BoT but I removed the box myself.

[Horace]

I had mine rebuilt at www.mandttransmissions.co.uk in Sheffield.  Good job.

 

I was also advised to contact Steve Brier - Leeds Gearbox specialist.  Phone no. 0113 263 2073

 

Good luck!!

[FLD]

Leek transmissions are pretty good. Sent from my iPhone using Tapatalk

[SteveA]

Would it not be easier to try and find a lower mileage box? Must be plenty around

 

That's what I did £50 for a Zaf box, worked a treat.

[turbo boy]

Hi Aimy, I used A1 gearboxes in St Neots years ago on another car and they did a bloody brilliant rebuild on mine 👍

[garyk220]

Do you know if the DZ box is a straight fit or do you have to swap components over to the original box?  I read that only AF F23 boxes will fit the turbo.

 

There was a DZ box from a Zafira turbo on ebay last month. I nearly took a punt on it.

 

 

could buy a DZ gearbox for a 3.95 final drive

 

[SteveA]

DZ from the Zaf GSI is a direct fit, nothing to change. The ratios are a bit different but it gives a bit better acceleration.

[Nev]

[font="arial, helvetica, sans-serif;"]FYI:[/font]

 

[font="arial, helvetica, sans-serif;"]AF = 3.63 Final Ratio (Part=24451449)[/font]

[font="arial, helvetica, sans-serif;"]DZ = 3.95 Final Ratio (Part=24461371)[/font]

 

[font="arial, helvetica, sans-serif;"]Also bear in mind the gear ratios between these boxes might differ (not just the final drive ratio).[/font]

 

[font="arial, helvetica, sans-serif;"] [/font]

Edited by Nev, 11 May 2016 - 02:59 PM.

[D-DAWG83]

DZ from the Zaf GSI is a direct fit, nothing to change. The ratios are a bit different but it gives a bit better acceleration.

Was under the impression that both the tubby and the NA had the same box anyway.

[techieboy]

Nope. Different bellhousings and different ratios and final drives.

[SteveA]

Technically they do have the same box though (other that the things Matt has mentioned)

 

Zaf GSI is a ZLet so the bellhousing matches the VXT.

Edited by SteveA, 12 May 2016 - 09:00 AM.

[siztenboots]

There are some minor changes like breather is on top

[Bumblebee]

Think I might be best sticking with the original box, any quicker lower down might make it uncontrollable with 345lbft torque? Sent from my E5823 using Tapatalk

[siztenboots]

thats more of a rear tyre issue, but you are right its got a nice range that 3rd gear works for most tracks and plenty of torque throughout.

[Nev]

In the past I used to prefer the longer ratio of the standard VXT box, but slowly over the years I've changed my mind and now think it would be better to have a lower ratio gearbox even if it does mean 1st and 2nd will be more deadly. The reason is that 5th gear is more or less unusable on the OEM box (apart from being a good motorway cruise gear). This means that when you are pedalling hard, you only have 4 gears to use in practice as 5th is only usable at properly high speed on a tuned VXT. If you have a higher than normal rev range up to say 6000 or 6500 RPM (which most tuned VXTs do have) then even 4th gear is probably not used as much as it might be if the final drive ratio was to be lower.

 

Basically a lower final drive ratio offers 2 things that I can see:

1/ More torque to the wheels, hence faster acceleration, on powerful VXes this is bad news for 1st and 2nd gear, but good for 3rd, 4th and 5th.

2/ More usable gears (5 instead of 4 in practice), so you have more flexability of revs and can stay in the power band more easily.

 

 

 

 

Edited by Nev, 12 May 2016 - 11:43 AM.

[chickendippers]

In the past I used to prefer the longer ratio of the standard VXT box, but slowly over the years I've changed my mind and now think it would be better to have a lower ratio gearbox even if it does mean 1st and 2nd will be more deadly. The reason is that 5th gear is more or less unusable on the OEM box (apart from being a good motorway cruise gear). This means that when you are pedalling hard, you only have 4 gears to use in practice as 5th is only usable at properly high speed on a tuned VXT. If you have a higher than normal rev range up to say 6000 or 6500 RPM (which most tuned VXTs do have) then even 4th gear is probably not used as much as it might be if the final drive ratio was to be lower.

 

Basically a lower final drive ratio offers 2 things that I can see:

1/ More torque to the wheels, hence faster acceleration, on powerful VXes this is bad news for 1st and 2nd gear, but good for 3rd, 4th and 5th.

2/ More usable gears (5 instead of 4 in practice), so you have more flexability of revs and can stay in the power band more easily.

 

 

 

 

 

I think the lower ratio box would be better for the "stage 2 is best" crowd, at your power I'd say longer is better. How often are you actually at high revs in 5th unless you're doing a top speed run