Aircooled t25 convirsion to deisel

Post by **HirMiller** » 30 Aug 2007, 16:26

Russell is more of an expert at this than I will ever be, If the TDi is later than 1994 it will most likely have a Immobiliser in the ECU.

1) Get the key + transponder that matches the ECU(even better get the intrument cluster as well as most of them hold a 4 digit pin that you use to code a new set of keys)

or

2) Spend £130-£200 and get a geek to remove the Immobiliser

If you get an engine prior to 1993 it will most likely have the old type injection system commonly found in Audis

I think it will be the better choice in the long run, better fuel econ, more power, chippable + AAZ engines are selling at a premium not because T25 people want them but also MK2 golf people want them.

Post by **gypsy** » 31 Aug 2007, 11:33

got the quote for the convertion and wont be using them

could buy a compleatly new van for the same money as the convertion (eeekk)

so will be looking to do it myself

so are you saying go for the later engine such as a 2000 passat ??

ta marc

Post by **toomanytoys** » 31 Aug 2007, 11:47

The reason it cost a lot of money is because it isnt a simple job to Tdi... and syncronutz will do a professional job that works...

There have been several people that have started this project and given up...

As I said.. depends on what engine you can get.. but any later engine you will need the ecu, keys, steering lock etc etc from the same car...

Post by **HirMiller** » 31 Aug 2007, 12:15

You are right about that, I have started this project and every day I want to give up, but I think it will be worthwhile in the long run.

Post by **gypsy** » 31 Aug 2007, 12:59

I know its a lot of work and would cost alot to do the conversion, it would be cheaper for me to sell the gypsy and get another, the conversion price was almost as much as the van cost me but thats not the point

i want to get better driving and better feul economy etc etc

so a diesel conversion makes sense to me, just nee pointing in the right dorection for the parts I need

ta marc

Post by **Russel** » 31 Aug 2007, 13:24

Ok just a little insight into TDI's and the totaly different PDI's(the ones u are mistakably looking at without nowing.)
Fitting a TDI isnt just sort out the wireing and install with a bit of fadricating.
U have speed sensors,foot pedal sensors,coded key(in the later PDI's this is in the clocks)gearbox rebuild with longer and stronger gears,intercooler or charge cooler instilation(a very important thing is to get the correct charge temperature)stronger clutch and many more things involved.
U get 90bhp and 110bhp in the TDI's then u get the totaly different 90,108,130,150 these are the later PDI's of wich there are 2 varients AND THESE NEED TO BE MOUNTED UPRIGHT WITH AN ADAPTER PLATE.
Another big thing u neede to consider is how many gearbox rebuilds u can afford over the lets say 5 years before u decide on ure engine.
And converting an Aircooled to water cooled has a lot of hidden instilations involved that u will only realise once u have started the job.
And then with a gypsy u have the very orquidnes of not being able to stand at the rear of the vehicle whilst working on it.You have to constanty clime in and out of it and hang ureself over the engine bay.
All these factors add up to an enourmouse amount of time and offcourse time = money.
These are but a few things to consider and a few things involved.
Russel

Post by **toomanytoys** » 31 Aug 2007, 20:30

How about a 2L type 4 engine designed specifically for pulling the weight of a bus???
you will get more power and torque.. and better mpg... but it wont give as good as a TDi mpg.. and it will be reliable... but it will be at a price... still......

Post by **gypsy** » 01 Sep 2007, 07:58

toomanytoys wrote:How about a 2L type 4 engine designed specifically for pulling the weight of a bus???
you will get more power and torque.. and better mpg... but it wont give as good as a TDi mpg.. and it will be reliable... but it will be at a price... still......

its already got a type 25 2.0l with twin 40's 009 etc etc

going to put an old t254 dizzy back on as advised

ad it pushes this along but fully loaded with wife baby and all the camping stuff for 2/52 am only getting 12 - 15 to the gallon, max 200 miles to the tank, ouch

would it be worth me getting a diesel t25 and using all the bits ??

ta marc

Post by **gypsy** » 01 Sep 2007, 08:01

Russel at Syncro-Nutz thank you for the info in your last post, its has been very informative and has given me more of an insite into what I would be up againt

am toying with the idea of maybe selling this gypsy and getting a later one with a diesel engine in

but am attatched to this one so would seem a shame to sell

Post by **toomanytoys** » 01 Sep 2007, 08:43

There is quite a bit of difference from a std engine that has carbs on it, to the engine I mentioned.. the engine is designed to pull a bus (+fully loaded trailer too) with heads and Cr, cam etc developed to suit..

Has it been on a rolling road?, I would suggest it would really benefit a rolling road session to optimise settings and yes the std dizzy would be better or you could consider a Mallory dizzy with even better setup.. but this requires someone with intimate knowledge of the Mallory and what make s a Type4 tick...

Also if set up on a rolling road.. you may find you get a bit better mpg.. so could consider an LPG conversion..
Then factor in what any engine conversion might cost to how much saving you might make and see how many miles you have to do before it is effective..
spending 5k (number from thin air as I dont know what it would cost to pay someone to convert) to get better mpg, might sound like a good idea, but when it may take 5+ years to pay for itself... is it actually worth it?
How many miles do you do?? buy a cheap small car for running around in...?

A friend had a BIG american v8 petrol camper it did 15-18mpg, but as he only used it for holidays and maybe 3000 miles year.. it wasnt going to be worth the effort and cost of swapping to a big D, or even LPG (big tanks) was marginal..

Even converting to std TD will be an effort as no cooling system etc... so maybe a later TD is on the cards!!!

Post by **HarryMann** » 01 Sep 2007, 09:24

The 1.9 NA or 1.9TD engine would be a cheaper option than a Tdi, but you will still need a lot of work and expense..

The Subaru 2.2 is another option, plenty of low-down torque and as they rev higher, no problem with the gearing I'd say. Better economy than present I'd say as it'd not be stretching every muscle, but the conversion bits would cost £1000 at least... the engines are still relatively cheap. Could also be LPG'd in the future...

But really as TM says, unless you really want a big project to get your teeth into, on a payback basis, you really have to do some meaningful sums, as it would take a lot of difference in MPG over a lot of miles to actually say you've broken even, let alone saved money

I would think even with a 1.9 TD diesel you'd struggle to get 25 mpg out of that rig, and 20~22mpg might be nearer the mark. Be realistic and do your sums on that basis... (Iit sounds like your current figures are realistic, so work on an improvement of 5mpg, from 15 to 20 and then you won't be dissapointed)

Post by **andysimpson** » 01 Sep 2007, 17:55

Putting the standard dizzy back on is a waste of time with them carbs.

Post by **toomanytoys** » 01 Sep 2007, 19:19

Come on Andy, dont say it wont work without a reason and not offer a solution... you are beter than that...

IIRC I did say IF the carbs have a dizzy vac take off... it would be worth trying...
The advance curve in the std dizzy is much faster than an 009... so should help..

What timing have you got it set too??
The 009 HAS to be set at 3000rpm + to get a max advance of 32 ish... I would be looking to acheive the same with the stock dizzy with vac disconnected... (Well that what I ran a 1.7L high compression "W" at)

As I said rolling road and try either would be the best solution for the mean time...

Post by **andysimpson** » 01 Sep 2007, 20:14

toomanytoys wrote:Come on Andy, dont say it wont work without a reason and not offer a solution... you are beter than that...

IIRC I did say IF the carbs have a dizzy vac take off... it would be worth trying...
The advance curve in the std dizzy is much faster than an 009... so should help..

What timing have you got it set too??
The 009 HAS to be set at 3000rpm + to get a max advance of 32 ish... I would be looking to acheive the same with the stock dizzy with vac disconnected... (Well that what I ran a 1.7L high compression "W" at)

As I said rolling road and try either would be the best solution for the mean time...

Vacume is too erratic, very small throttle movements just kill the vacume signal, it may have enough at motorway speeds to help economy slightly bit the rest of the time the vacume is a waste of time. It would be better to increase base timing and do without it. Every engine is different and timing would be best set to ideal rather than supposed safe figures, one of mine is set at 28-30 at idle and then has centrifugal advance and vacume.

I am not a fan of rolling roads having set lots up and thinking they were ideal and then going down the road in fresh air to find there not right. I operated a dyno for a company trying to do away with the air flow meter on six pot jags, they were trying to different types, MAP sensing and Hot wire both worked better on the dyno than flow meter but were hopeless on the road. Bad things also happen on dynos, i had one with a diff that broke just as it came out and my boss blew up a V12, also lots of head gaskets.

Post by **HarryMann** » 01 Sep 2007, 20:37

Yup, hard to simulate the airflow at 100mph or so, that's a lot of air cooling... and its probably only the top supercars that are made to actually be held flat out in every gear up to full chat in top.

Maybe things are better these days, Merc Sprinters seem to be held flat out in top a lot into headwinds