Defender Tdi300 LT230 1.30 ratio and Ashcroft ATB

[JamesP]

Hi everyone, just thought I'd share my recent activity in fitting an Ashcroft ATB and 1.30 ratio gear set in my Tdi300 Defender. The tdi 300 is typically recognised as being slow and noisy to drive but simple to fix. The simplicity is what I like about it. After considerable research including asking the Defender community both here and abroad if anyone had changed to a 1.30 ratio in the transfer box I bit the bullet and fitted an Ashcroft ATB and changed the ratio to 1.30.
Very pleased with the result. Now hardly any driveline backlash and has dropped the RPM by about 195 rpm at 100km/ hr. Doesn't sound much but it makes the Tdi300 Defender much nicer to drive.
With the std 1.4 ratio the Tdi300 is reving at 2534 at 100km/hr or 2410 at 95km/hr. With the 1.30 ratio the revs drop to 2330 at 100 and 2220 at 95km/hr . There is a reduction in power but it isn't a slug to drive. If anyone is familiar with the Gateway bridge in Brisbane it is steep. The Tdi300 went over the top in 5th gear at about 90km/hr, no problem.
Now, with the 1.30 ratio fitted it hums along nicely at 95 km/hr. With no airbags and ABS I'd suggest it it not the safest vehicle to drive at high speeds and I don't want to drive the old rig much faster that 90-100km/hr, so all good.

In summary, a good upgrade.

regards
James

[Plutei]

Hi James, I'm considering the same upgrade but without the ATB and I'm just tossing up which ratio to get. Do you think the 1.3 is preferable to the 1.2 ratio?

Cheers

[JamesP]

Hi,
I pondered and researched for a long time on what to do. I emailed Dave Ashcroft who indicated that they sell a lot of the 1.3 ratios for Tdi1 110/130 in England. I didn't get a response from anyone in Aust indicating that they had the 1.30 ratio, most said they had the 1.20 and in some cases had negative comments about the power loss.
Feedback was that the 1.2 in a Tdi had trouble taking off in first gear if towing or if the vehicle was loaded. Also given the Tdi is not overly powerful and I don't want to tune up the engine I figured that the 1.3 would provide a good balance of lower rpm but still enough power so that it didn't die when approaching hills.
In my humble opinion 1.2 might be ok in a TD5 where it has a bit more power and can be chipped but for the Tdi I think the 1.30 is a good choice.
regards

[Parker]

Hi everyone, just thought I'd share my recent activity in fitting an Ashcroft ATB and 1.30 ratio gear set .....
James

James why did you choose to get the ATB? And what have you learned since fitting it?

Why I am asking: I have a 1.20 TC on order for my TD5 Def but am considering adding the ATB....but it is another A$650

Thanks.

[ashtrans]

glad you like it James !

Dave Ashcroft

[JamesP]

Hi Parker, I fitted the ATB as I had a lot of backlash in the centre diff and I wanted to remove as much backlash as possible. Also I drive on a lot of dirt roads and liked not having to engage the diff lock.
Regards.

[mox]

I have an LT230 in Defender that has ratios 1.27:1 in high and 4.21:1 in low (Standard is 3.32:1) Wanted something a bit faster than 1.41:1 in high. Anyway, starting of with an LT230 that from serial number came out of early rangie with Torque-Flite auto and 1.003:1 high range, I did some looking, measuring and thinking. Then had a new input gear designed and cut. The standard 26 tooth input gear drove the 41 tooth middle gear on the intermediate cluster. The new gear is 22 teeth which drives the 44 tooth high range gear at the rear. rather like the setup in Series transfer boxes but back to front. Anyway, I think it is a considerable improvement on standard and the only disadvantage is sill a bit noisy at high speeds and probably will not get any quieter. Have not heard of anyone else trying this setup. Note low range is similar speed to 30% reduction Maxidrive type conversion. I did sent Dave Ashcroft some photos of my standard and new gears. Was interested but don't know if it was ever a priority for him to try. Anyway he has come up with this 1.30 high range conversion.