 | Home > Maintenance & Modifications > LT230 - 1.301 ratio gearset feedback |
 
|
|
|
| Shroppy Member Since: 25 Feb 2016 Location: Shropshire Posts: 866   
|
I've looked through the forum and can't find a great deal of feedback on the 1.301 ratio gearset offered by Ashcroft. I can See JST seems pretty happy with it in his 130, has anyone else opted for it?
I've been playing with their ratio calculator but it's rather difficult to relate to real world driving without actually trying the different ratios. The application I'm considering it for is as follows, 130 DCPU - 4.6 RV8 (approx. 270bhp, 270lb/ft) - R380 with V8 fifth - LT230 with ATB (ratio to be decided) - 285/75/r16 or 235/85/r16 tyres Probably 80-90% on road, 20-30% of which loaded or towing. I had the stock 1.410 ratio in my 200tdi 110 on 235s for most of my ownership and like most, I found it to be a bit short for motorway driving but about right for towing and general driving. I then swapped it out for a 1.22 ratio box which was by comparison was much nicer, certainly requiring more revs but nothing major. Not very good for towing though. I had thought 1.22 would be the way to go given that the V8 will be a more capable engine, but I'll be upping the gearing with the 285s and the V8 5th gear so now I don't know. 
Any and all feedback welcomed! 1985 127 V8 Build Thread Series 2 109" Series 1 80" |
||
22nd Mar 2021 4:25pm |
|
| geobloke Member Since: 06 Nov 2012 Location: Nottinghamshire Posts: 4410
|
Hello Shroppy. You have a good project in the planning then.
I have heard good things about the 1.3 gearing and if I had not recently put a 1.4 back in to my 110 I would have probably gone for that. Previously I had a 1.2 fitted and found that whilst the cruising was much more refined the everyday journeys and traffic driving was irritating, especially the continual up and down shifting in a 30 limit. Now that I have a 1.4 this irritation has vanished, much better gearing for (as you say) towing and general driving. The fitting of 285/75/16 tyres exacerbated the taller gearing with the 1.2, but is perfect with the 1.4. I would expect that fitted with a 1.3 and you'd have the best of both worlds there. I do not have a V8 5th gear fitted, but an overdrive and although not the same they aren't dissimilar in ratio. The overdrive plus the 285s plus the 1.4 transfer gearing are a superb setup allowing for IMHO the choice for every gearing related situation. I absolutely love 285s, 4th, high and OD engaged as a cruising gear. Around North Wales with its long hills 5th and overdrive is too tall for the TD5, 4th and overdrive and she'll pretty much cruise up hill and down dale. Incidentally I chose the standard 5th and overdrive because even with a mildly tuned TD5 the relatively weak 5th gear shattered whilst cruising at 70mph one day. Makes quite the noise when it goes I can tell you. My 110 is my daily, she's no lightweight having a full cage etc fitted and although only a tuned TD5 it is probably within spitting distance of the weight and size of vehicle you are building. That being the case you can compare those ratio stats with what you want to do. I hope that helps, if only a little bit... |
||
|
22nd Mar 2021 5:08pm |
|
| jonny Member Since: 10 Mar 2013 Location: North Wilts Posts: 167 |
I've got a 4.6 in my 110, ZF 4HP22 Auto and a 1.4 transfer box. Also running 285 75 16s.
It looks like 4th in the ZF is 0.728:1, and the manual box is 0.732:1 - so the auto is geared a smidge higher. I find it fine for driving round, it'll happily cruise on the motorway at 70 and is in the power band enough that if you put your foot down it will pull. The v8's like a few revs - peak torque is around 3000rpm not 2000odd like the diesels.. When I got it, it had a 1.2 transfer box (but a 3.5 v  and I didn't like it - it was sluggish and didn't lock up the TC until 65ish and always felt overgeared. With 235 tyres you might get away with it as they are a fair bit smaller.. |
||
|
22nd Mar 2021 7:53pm |
|
| jst Member Since: 14 Jan 2008 Location: Taunton Posts: 8106  
|
Whats the rpm at 50, 60 and 70 for your setup , run that through calculator with different t box ratios and see where it comes compared to where the engine wants to be.
1.2 , std r380 gearing, 3.54s and the 33 tyres I reckon for 4.6. Cheers James 110 2012 XS Utility 130 2011 M57 bespoke Camper 90 2010 Hardtop 90 M57 1988 Hardtop |
||
|
22nd Mar 2021 9:02pm |
|
| rallysteve Member Since: 10 Feb 2014 Location: Cumbria Posts: 2237 
|
Briefly had an R380 with V8 fifth gear, 1.2 ratio transfer box and 255/85 tyres on my V8 90. Was too high geared for my 3.9 at least. Fifth was pretty unusable until 55-60mph and just made the vehicle feel very sluggish. Now back to a 1.4 ratio transfer box which is much better in my opinion. Currently have the rev limiter set at 4000rpm and only really ever trouble it ik second or third.
Steve 02' 110 TD5 Double Cab Rebuild Thread |
||
|
22nd Mar 2021 9:47pm |
|
| Linds Hanson Member Since: 16 Jan 2021 Location: Cornwall Posts: 487
|
We always fit 1.4 gearing on RV8 Defender builds even with 5.2 capacity. The higher gearing makes them lifeless in higher gears on the motorway resulting in loosing speed on inclines unless a awkward change down to fourth is carried out.
|
||
|
23rd Mar 2021 11:02am |
|
| Shroppy Member Since: 25 Feb 2016 Location: Shropshire Posts: 866
|
Thanks all for your responses, a quick table of outputs from Ashcroft's ratio calculator:
 Click image to enlarge Based on the above I think option 1b or 2a will be about right. I've already got the V8 5th ratio gearset in stock which is pushing me towards 1b. That, and the fact the lower gearing should equate to better acceleration.
I'm expecting about 280lb/ft max torque with most of that available from low revs, so pretty similar to a hot TD5 I guess. 1985 127 V8 Build Thread Series 2 109" Series 1 80" |
||
|
23rd Mar 2021 8:34pm |
|
|
|
| All times are GMT |
< Previous Topic | Next Topic > |
Posting Rules
|
Site Copyright © 2006-2025 Futuranet Ltd & Martin Lewis
