Fairey Overdrive V8

Started by Boxoftricks, Apr 27, 2024, 04:06 PM

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Serious Series

Quote from: Boxoftricks on Apr 27, 2024, 10:00 PM
Quote from: Richard on Apr 27, 2024, 09:22 PMWould an Ashcroft high ratio transfer box work?
Richard

Great shout and cheaper option. I'll give them a call.  Has anyone fitted one?
I have a HRT case fitted on my 200DI series 3 but I understand they are no longer selling them , I beleive it is because they cannot get the new gears manufactured to the same standard as they where getting them made.
Ask them I maybe wrong just forum and internet chats!

Richard

Quote from: Boxoftricks on Apr 27, 2024, 10:00 PM
Quote from: Richard on Apr 27, 2024, 09:22 PMWould an Ashcroft high ratio transfer box work?
Richard

Great shout and cheaper option. I'll give them a call.  Has anyone fitted one?
In fact it was Diffwhine who suggested it to me when I considered putting in a Roamerdrive for similar reasons (noise and consumption). If this is the one, and I think it is, it's still on their website.
Richard
'64 S2a
'85 RRC

diffwhine

If you provide the gear and the casing, they do still seem to offer it. JohnB has one in his 58.
1965 2A 88" Station Wagon

NoBeardNoTopKnot

#18
I looked at the Ashcroft solution.Seriously considered it. Ashcroft are not far from me.

 It's some £360ish and that's how such things work. Pocket-calculator not required and self-install, it's doubtful it can be done and dusted, all told for £450. Reckon on closer to £500.

For the OP it'll be nicer to drive - ROI is never happening. If we're trying to save money, leave it be.

JonB

Yep, fitted one this winter after trying a borrowed 3.54 diff.

I like it, half the cost of an overdrive and without the issues of parts availability, and doesn't affect low ration like diffs.

You send them a bare transfer case, and they re-machine the intermediate gear shaft in a new position. They send it back with a new set of gears to reassemble with.

I went this route based on originality-O/Ds weren't an option in late '58 and I didn't want to put a hole in my one-piece floor. I'm also on 6.00 avons and 45mph was about as quick as you'd want to go. First gear was just about pointless in normal driving.

Cost/spares, as above, I was rebuilding the box anyway so it was out and in pieces. Also no need to replace/calibrate the Speedo.

Proven, using the RR diff for a month or two meant that I knew the std petrol engine could happily manage the 30% ingress in gearing without issues.

I can now trundle around at 45/50 and the whole truck feels so much more relaxed with 55+ easily reached.

For me, it was an easy choice, even with a stock motor. A tdi or v8 would make even more sense with the extra torque to pull away in first.

If anyone wants to try one, I'm near bath.

Jon




Serious Series

Nice to know they are now back in stock.

GlenAnderson

I have 3.54 diffs, 235 tyres and a Roverdrive behind my 200tdi.

I would suggest that a high ratio transfer box, together with basically the same diff/tyre combination will be too high geared. It'd be like driving around with the overdrive permanently engaged, which would be too much for my setup, definitely.

Wittsend

#22
An overdrive is NOT going to improve your mpg  :shakinghead

How you drive it can help ... soft right foot and a stronger throttle return spring might help.

Having the timing setup optimised, fitting electronic ignition will help.
All the engine settings, plugs, points, valve clearances etc.

Remove all unnecessary load weight, tool boxes, spare wheels and roof rack.

No one has mentioned FWHs - they won't help save fuel  :shakinghead



diffwhine

Quote from: Serious Series on Apr 28, 2024, 10:58 AMNice to know they are now back in stock.

I think more likely they just build to order.
1965 2A 88" Station Wagon

Boxoftricks

Quote from: JonB on Apr 28, 2024, 10:35 AMYep, fitted one this winter after trying a borrowed 3.54 diff.

I like it, half the cost of an overdrive and without the issues of parts availability, and doesn't affect low ration like diffs.

You send them a bare transfer case, and they re-machine the intermediate gear shaft in a new position. They send it back with a new set of gears to reassemble with.

I went this route based on originality-O/Ds weren't an option in late '58 and I didn't want to put a hole in my one-piece floor. I'm also on 6.00 avons and 45mph was about as quick as you'd want to go. First gear was just about pointless in normal driving.

Cost/spares, as above, I was rebuilding the box anyway so it was out and in pieces. Also no need to replace/calibrate the Speedo.

Proven, using the RR diff for a month or two meant that I knew the std petrol engine could happily manage the 30% ingress in gearing without issues.

I can now trundle around at 45/50 and the whole truck feels so much more relaxed with 55+ easily reached.

For me, it was an easy choice, even with a stock motor. A tdi or v8 would make even more sense with the extra torque to pull away in first.

If anyone wants to try one, I'm near bath.

Jon





Thanks Jon, having read your review think this is the route for me to take.  With the additional power of the V8 don't think over gearing will be an issue. Right now 1st is basically redundant anyway.  How long did it take for them to machine it?  Thanks

diffwhine

You need to start with a Suffix C or onwards gearbox transfer box casing and you will need the low range gear (36 tooth) from a Suffix C onwards transfer box to make this work (532979).
https://ashcroft-transmissions.co.uk/product/high-ratio-transfer-case-kit/

One point I would emphasise is that building the transfer box properly is essential with this kit. Once its done, its great, but you must follow the WSM set up procedure to the letter.
1965 2A 88" Station Wagon

Boxoftricks

Hi,

Where is the stamp on the transfer case so I see what suffix I currently have.

Will Ashcroft build up the kit for you or is it DIY?

NoBeardNoTopKnot

Quote from: GlenAnderson on Apr 28, 2024, 12:12 PMI have 3.54 diffs, 235 tyres and a Roverdrive behind my 200tdi.

I would suggest that a high ratio transfer box, together with basically the same diff/tyre combination will be too high geared. It'd be like driving around with the overdrive permanently engaged, which would be too much for my setup, definitely.

Save for splitting-hairs (if by different means) you've the same grunt and torque at the same rpm as my set-up. I run 7.50 x 16. I see you've 3:54 & your Roverdrive. That seems like it's going to be too tall. Are you saying you wouldn't add a high-ratio box to your set-up - I'd agree - or, that'd it'd be too tall for the OP? With grunt as ours,  I'm thinking we want:

1) Stock + Overdrive
2) Stock + 3.54 (1st a bit high for a 2.25)
3) Stock + HR Transfer (1st a bit high for a 2.25)
4) Stock + 5-cog box.

ie: Overdrive or 3.54, or HR, or 5 cog. Pick any one, not two. Only you appear to have gone for more?


Craig T

I had a series 3 with a Fairey overdrive for years behind a 3.5 and we later rebuilt the vehicle with a 4.6 Rover V8 and it's still going strong so they are well up to the task if driven sensibly. That vehicle also has 3.5:1 diffs and large tyres and it will cruise quite happily at 60mph

I would try to find a Fairey unit and fit it to give it a go. If you don't like it, take it off and sell it on again, you won't lose money on them.

Craig.

diffwhine

Quote from: Boxoftricks on Apr 28, 2024, 04:17 PMHi,

Where is the stamp on the transfer case so I see what suffix I currently have.

Will Ashcroft build up the kit for you or is it DIY?

The number of the transfer case is the gearbox number although of course there is a risk it may have been swapped in the past. You can't easily tell by just looking at it. You would need to take the bottom cover off and count the teeth on the high range gear. The number is stamped on the side of the gearbox top cover on 2, 2A and early S3 vehicles. After that the number was stamped on the top back of the gearbox casing where it joins the transfer box.

Ashcroft will not build it up. It is a DIY job or find somebody who is OK with setting up a transfer box properly. If you need help and want to do this, let me know. I may be able to assist as you aren't too far away from me I guess.
1965 2A 88" Station Wagon