Improve power or change ratio?

[Will F]

I swapped my TD5 110 double cab transfer box for a Disco 2 box to give her longer legs. Works great but I am getting tired of the first gear hill starts - especially when off road.

What is the best (cheapest? easiest??) solution?

More power? If so how much more would be necessary?

Change the gear ratio? I think this might be a rather expensive option !

thanks,

Will

[Retroanaconda]

Put a 1.4 back in?

Or change the diff ratios, this will affect all gears though, and the speedo reading. Or fit an underdrive?

[Bowie69]

Or when off road, stick it in low range?

[errol209]

Doesn't the low range ratio stay the same anyway, with the quoted ratio just being the High range one?

So your Disco TBox would have a 3.32:1 low ratio anyway?

[reb78]

Fit the 1.4 back in and get an overdrive - best of both worlds then! Can only assume you mean hill starts in 1st hi range as, like the others have said, low range ratios are unaffected. There is a GKN OD on ebay now - i'm pretty happy with mine.

[Will F]

THanks for the input - even the suggestion to put the old transfer box back...and the underdrive Think I will experiment with remapping and larger intercooler. I am sure that will give what I need.

How much power difference is there from purely upgrading the intercooler? My problem is that living in Cape Town on the slopes of table mountain there is a lot of dtrain on the clutch with all the hill starts. I am hoping a litle more power will sort this out!

[western]

on the slopes of table mountain there is a lot of dtrain on the clutch with all the hill starts. I am hoping a litle more power will sort this out!

in that case use low range 1st or 2nd to get the vehicle rolling & learn how to range change [low to high] on the move, this will help your clutch last much longer & have a bit of an easier life.

[reb78]

THanks for the input - even the suggestion to put the old transfer box back...and the underdrive Think I will experiment with remapping and larger intercooler. I am sure that will give what I need.

How much power difference is there from purely upgrading the intercooler? My problem is that living in Cape Town on the slopes of table mountain there is a lot of dtrain on the clutch with all the hill starts. I am hoping a litle more power will sort this out!

Not much to be gained from the intercooler alone. Really need to up the boost and fuel to suit it. The intercooler will only help IMHO if you are currently overfuelling a bit by allowing the air in to enable that fuel to be burnt.

[JST]

Will, you asked a question and everyone replied saying change ratios! if you are adamant to boost the power then so be it but it wont help with the issues were you are currently experiencing problems with out causing excessive component wear.

Did you have an issue pulling away before changing to a 1.2 box?

[Bowie69]

 

lot of strain on the clutch with all the hill starts. I am hoping a litle more power will sort this out!

More power will be more strain, you can't get away from that.

Drop back to the 1.4 and see how you get on, failing that, fit an auto, no more clutch or hill start problems ever again.

[Will F]

Will, you asked a question and everyone replied saying change ratios! if you are adamant to boost the power then so be it but it wont help with the issues were you are currently experiencing problems with out causing excessive component wear.

JST - just didn't get the answer I wanted to hear - which is that it is quick, cheap 'n easy to drop the ratio of first gear without affecting the others. Clearly there is not.

Drop back to the 1.4 and see how you get on, failing that, fit an auto, no more clutch or hill start problems ever again.

I never had a problem with the 1:4 so yes this would be a solution...but not the answer I was looking for

Basically the 1st gear with the 1:2 box in the Defender is like pulling away in 2nd with the 1:4 box in a 90. Very doable and no strain on the flat but takes a touch more clutch work on an incline.

The real problem is this (not sure why it has taken me so long to explain it accurately)

The vehicle feels underpowered,un-responsive and in the wrong gear when pulling away or driving slowly up a hill in first. It takes too long for the revs to climb to get the turbo to kick in.

So maybe the solution is to get the turbo to kick in sooner. The power I was actualy looking for was to assist for the period before the turbo kicks in. Is there a solution to this perhaps?

[FridgeFreezer]

So to summarise: You fitted a transfer box with the wrong ratios for the vehicle and now it feels wrong and you want to know how to fix it?

Smaller tyres are the only answer.

[Bowie69]

Or fit both transfer boxes one after the other and have a set of gears for driving up hills, and one for the flat.

Or fit an auto.

[Tatt]

Howdy

I fitted the 1.2 ratio to my TD5 Defender and then took it to BAS, who got rid of the egr and centre box and then mapped it. Now have absolutely no hassle pulling away on any hill.

Will be well worth your while to have a chat with Pete at BAS and see if he can do anything for you.

Tom

[western]

Howdy

I fitted the 1.2 ratio to my TD5 Defender and then took it to BAS, who got rid of the egr and centre box and then mapped it. Now have absolutely no hassle pulling away on any hill.

Will be well worth your while to have a chat with Pete at BAS and see if he can do anything for you.

Tom

a touch difficult to get the vehicle to BAS when it resides in the OP's location of South Africa

[Lara]

Fit an Auto box!

Manuals are old school

Lara

[Will F]

fitted the 1.2 ratio to my TD5 Defender and then took it to BAS

Thanks Tatt, EGR and centre box removed already. Have not remapped yet though. Thanks for that feed back as it seems just a slight tweak is necessary to give that little bit more to get to the higher revs quicker.

Might be cheaper to buy a new Puma than to take my TD5 to BAS I'm afraid

The changing to auto and replacing the old box all seems a little drastic for this problem. Thanks all. I must say an auto box does sound interesting. The only ones in a Defenderthat I know of here are V8's. Can you slot the Disco auto box straight in?

What about the ECU? Will it not kick out a bunch of errors?

Thanks all.

[Top90]

I had the same issue with the Td5, with the 1.2 T-Box it was not good in traffic as 1st was a bit high. Had it remapped and it was better, but it was never as good as it was with the 1.4 T-Box. But with the 1.4 it was noisy at motorway speeds (70mph here).

The auto conversion has been done many times. Ashcroft Transmissions (I know you are not in the UK) have some info on thier website here:

http://www.ashcroft-transmissions.co.uk/index.php?act=viewCat&catId=7

I bought a Puma in the end. 6 gears, all rations fine and I never felt the need to chip or remap it either.

[Tatt]

Thanks Tatt, EGR and centre box removed already. Have not remapped yet though. Thanks for that feed back as it seems just a slight tweak is necessary to give that little bit more to get to the higher revs quicker.

Might be cheaper to buy a new Puma than to take my TD5 to BAS I'm afraid

The changing to auto and replacing the old box all seems a little drastic for this problem. Thanks all. I must say an auto box does sound interesting. The only ones in a Defenderthat I know of here are V8's. Can you slot the Disco auto box straight in?

What about the ECU? Will it not kick out a bunch of errors?

Thanks all.

Have a chat with Pete and see if it can be done online. Or see if just swapping the ecu for a tricked-up one will be ok? If so, I might be able to bring one out for you in December when I visit my folks.

http://www.bellautoservices.co.uk/index.php?page=news

Tom

[longlandy]

Throw away the td5 fit a cummins 6bt 1:1 transfer box and pull away in second uphill with a trailer

[Snagger]

1.4 transfer box and an overdrive or Roverdrive would be my solution - tampering with the engine settings doesn't seem to prudent in Africa, where you could be stranded a long way from help of you blow the engine or transmission. GKN overdrives seem to burn out frequently from what I have seen at my local non-franchised workshops, but I have found my Roverdrive (on a SIII but powered by a Tdi) to be utterly reliable and very tough. The overdrive will give you a 28% gearing increase, which is more than the 1.2 transfer box gives, but is selectable and also works as a gear splitter. Still not a cheap option at nearly £1k for a new overdrive of either brand, but it's the easiest, most robust and most flexible option.

[widget]

1.4 transfer box and an overdrive or Roverdrive would be my solution - tampering with the engine settings doesn't seem to prudent in Africa, where you could be stranded a long way from help of you blow the engine or transmission. GKN overdrives seem to burn out frequently from what I have seen at my local non-franchised workshops, but I have found my Roverdrive (on a SIII but powered by a Tdi) to be utterly reliable and very tough. The overdrive will give you a 28% gearing increase, which is more than the 1.2 transfer box gives, but is selectable and also works as a gear splitter. Still not a cheap option at nearly £1k for a new overdrive of either brand, but it's the easiest, most robust and most flexible option.

^^ +1 what Nick says...

[Diff]

Just my opinion, but I would just put a 1.4 ratio box back in and wouldn't bother with an overdrive. If it is noisy, stick some more sound proofing in. I drove a laden Td5 110 station wagon all over Botswana and parts of SA. On some of the longer roads I was consistently doing 120 - 130 km/hr (75 to 82) mph for hour after hour, without being flat out. I never felt it needed a 1.2 ratio or an overdrive. It had thick mats and carpets and wasn't particularly noisy. I would rather spend £1000 elsewhere than on an overdrive. I am not convinced that a higher final drive will make the Td5 more economical either.

Regards,

Diff

[JST]

i had a GKN overdrive with a 1.4T box on my 90 td5. it worked very well. it was noticeably quieter at 70mph, dropping the revs about 600rpm or so. it pulled a treat with it too. it didnt give alot more top end speed as the engine couldnt push it (std tune). economy also went up 10-15% on a long run with it when compared to not running it. I had it fitted for 80k miles, changed the oil regularly and less a speed sensor switch going at 75k miles it was fine.

[Snagger]

i had a GKN overdrive with a 1.4T box on my 90 td5. it worked very well. it was noticeably quieter at 70mph, dropping the revs about 600rpm or so. it pulled a treat with it too. it didnt give alot more top end speed as the engine couldnt push it (std tune). economy also went up 10-15% on a long run with it when compared to not running it. I had it fitted for 80k miles, changed the oil regularly and less a speed sensor switch going at 75k miles it was fine.

I think it's the regular maintenance which makes the difference. Overdrives do get hot when engaged and can cook the ATF used in GKN units - regular replacement is very wise. Roverdrives also get hot and can quickly degrade mineral EP90, which it shares from the transfer box, so using semi-synthetic 75W90 is better.