5 speed jx

[dr jones]

hi,

have a few questions about our '90 5 speed jx van, its running standard set up at the moment, however due to long motorway periods(will cover 500miles a day to scotland etc) would like an extra 5-10mph without sacrificing fuel economy or the engine(averaging approx 55-60mph). So, is it possible to have the gearbox ratio's changed, if this is done will the engine be able to pull it well enough with the higher ratio( the engine is well serviced sound unit)and will we need to fit an oil cooler possibly???.or do we buy a t4 (last resort):( . Also who is the guy in warrington that does the gearboxes?. any help would be gratefull.

cheers.

[Hacksawbob]

Aidan is the Warrington Gearbox guy, Taller gears can be put in but its mega money (£800 for the cog alone from memory) you can fit bigger tyres for the gearing increase. There are plenty of diesel upgrades that folks do something to do with boost and fuelling and that kind of stuff, there is the rover boost pin which can help apparently although I think they all will be using some amount of extra fuel.
theres loads on here
http://www.brick-yard.co.uk/forum/t3-di ... page2.html" onclick="window.open(this.href);return false;

[Titus A Duxass]

I run a set of 215/65R16 wheel/Tyres all round, these are 5% larger than standard.
A good JX will cope but you need to change down more often on hills.

Fitting an oil cooler is highly recommended, I haven't fitted one yet as I'm thinking of sticking a 2E motor in.

[dr jones]

thanks for the info guys, have contacted aiden about the box etc, need to have a think about all this for a bit, but may consider the wheel change to try it out first, tho dont want lo pro tyres due to occasional off tarmac camping trips so will look into this side of things.

[phil_b]

Hi,

We fitted high profile, commercial/mild 4x4 tyres, 195x15 which were about 50mm larger dia. than standard, just on the rear so speedo remains accurate. Worked out about 8-9% above standard gearing. They look slightly big in the arch but ground clearance no problem.

Unfortunately you get nothing for nothing, if you then drive faster you will use more fuel and put more load on the engine. Drive at the same speed as before and you should return a small increase in mpg. We did it so we could cover more miles on long trips abroad at a reasonble speed. Returns no less than 30mpg at indicated 70mph, increasing to 35 if we keep around 60-65. That's on an AAZ conversion with ABN box.

Cheers.. Phil

[T-3PO]

Charge/intercooler? ... though I have yet to hear of anyone fitting one to a JX, would be very interested in finding out what the extra bhp/mph is or has the potential to be.

What did Aiden say about the gearbox? I have often wondered whether the JX has the grunt it needs to be able to handle a taller 5th gear??

... but of course there's always the 1.9 engine switch ......................... !

[Aidan]

Aidan said keep it simple, keep it stock, do the gearbox when the JX dies and is replaced with something with more grunt, and of course oil change it if not known history.
v max and final gearing all down to grunt and with respect JX doesn't have a lot but a good un running stock is perfectly acceptable in a 20+ year old 2+tonne van, ditto your 1.9 DG petrol, but you'll never win a F1 race in one

FYI I run standard engine and gearing, but with lpg as for me that was the most cost effective way of minimising fuel costs at the time (5 years ago), original engine 145k miles, will still probably get a vw wbx in when needs a new one, though depends how the scooby project pickup goes, and better syncro sump solution, if I get enough confidence with that then may change to a scooby engine in Edna, but as it ain't broke it isn't getting changed for the sake of it, better to spend money on fuel and use it......goes out to put battery on charge

of course if lottery is won and if porsche produce their 4 cylinder wbx then that would be nice maybe

[dr jones]

Coming to the conclusion that (as aiden is saying) keeping it stock simple is the best way, asked a few questions about wheel/tyre increasing and although good suggestions, might stick with originals and change the way we travel, ie maybe 500miles a day for 2 days in 1 week + 500 in between is asking a wee bit much of the old bus?. This oil cooler set up seems the most important now after reading various posts.

[T-3PO]

Thanks Aidan .. you've now saved me my "pipe-dream" money for a modded gearbox and as the gearbox is now out of the equation an oil cooler just got higher on the list

Dr Jones, best things I did to our pop-top camper ... lowered (45mm, fine on campsites with full load) slightly stiffened suspension, 16" wheels & wider tyres, polyurethene steering bushes, front spoiler - costs of about £1k and although it doesn't increase the speed it certainly makes doing the sort of miles you're talking about a lot more comfortable!