audi A3 engine conversion

[nicko868]

hey
just needing a bit of general advice really, i currently have a 1.9 petrol watercooled but am wanting to put an audi A3 1.9 turbo desil in it hopefully get a fewmoremiles out of it now i have all of the parts for it to drop straight in but i need a wiring loom making up for it .... i was wondering if anyone knows where i can get one made and well how much ish do you think it would cost ? cheers

[syncroandy]

If you're going with the original electronic TDI, you'll need the ECU and engine harness for your engine. If you don't have these, you may want to consider using a mechanical pump capable of generating the correct pressure for direct injection. What are you doing about the gearing ?

[nicko868]

hi yeah we have the wiring harnes and the pump off the a3 and i am not really sure about the gearing what would we need to do ?

[syncroandy]

Drop the revs down so they suit the TDI.

[nicko868]

ah right what do you mean by that? at the minute there is a four speed box in it from the 1.9 petrol caravelle will that handle the engine ?

[syncroandy]

Perhaps you might want to spend a bit of time reading up on this. A good starting point is the FAQ and 80-90 wiki, after that, Google is your friend !

[nicko868]

okay well i have all the bits engine wise just for it to drop in. i just need to sort the gearbox out

[toomanytoys]

just for it to drop in

I think you are really under estimating how much work you are taking on there I am afraid.. Lots of TDi how too's, questions and answers in here..

Bolting it in is one thing, making it run properly is another and then the gearing is the 3rd issue if you want it to be good..

[nicko868]

haha no i do realise how much work is involved but we have it all worked out up to the gearing , because we have been told that if the gearbox that is in is a high enough ratio then it will be okay but i aint sure how to find out the ratios ect ? i am guessing get the code off it. but no with the engine i have bought it has all of the bit required like all the stuff off the original diesil so the engine aint starved ect so yeah just gearbo quries really

[camper]

just for it to drop in

I think you are really under estimating how much work you are taking on there I am afraid.. Lots of TDi how too's, questions and answers in here..

Bolting it in is one thing, making it run properly is another and then the gearing is the 3rd issue if you want it to be good..

Agree the gearing is the issue there are some ratio information somewhere on the forums.

[nicko868]

yeah that is the issue i am trying to solve, the rest is sorted now where abouts on the forum can i find that info ?

[dickspanner]

Having completed the install of a Cosworth 2.9V6 in my crewcab I can confirm that putting alternative engines in T25s is very doable, however it is as Toomany says very easy to under estimated the task. However good luck with it, there are a lot of very knowledable people on here who may help.

There is a page somewhere which has gearbox codes on and what ratios etc you will have corresponding with the code on your box.

Dependant on what you are going to spend on this project of yours and to what level of detail you are going there are lots of things to consider.

Does the engine 'fit' onto the gearbox or will you need an adaptor plate? If so what type of plate are you going to go for?
What clutch are you going to use? Hydrolic/cable
What starter are you going to use? T25, Audi, Bespoke one?
How much of the T25 wiring harness are you going to use and how is it going to 'talk' to the Audi harness.
Does the Audi system have built in immobilizers, especially the ones run from the key fob and ignition barrel.
What ancillaries are you going to keep and dispose of with the Audi system. I removed a lot of stuff from the Cosworth engine and nobody wants to touch it to tune it as it is a none stock Cosworth engine management system.
If you are delivering higher torque/bhp through your drive train, are there any weak points like driveshafts, cv joints, bearings etc.

If you want a gearbox to stand upto the increase etc, is it in your budget to get one modified/built for you so no failure is inevitable or are you going to have spare gearboxes and replace them when necessary. If so speak to Aiden, he will sort you out.

In relation to your original question about the harness, when we stripped the harness out of the Cosworth it filled a box that was 4ft x 4ft x 2ft and took 2 people to lift it and it was controlled by 9 brains. We spent 5 days working on the harness, purchased original wiring diagrams from Cosworth, haynes and other sources and had a lot of people help us with it, but we got there in the end. We stripped it down to 1 brain, took about 14 sensors off the engine and got it down to 4 fuses, instead of about 90. When the harness was originally laid out it was about 20ft x 15ft and we got it down to a skeleton harness which would fit in a box maybe 1ft x 1ft x 1ft.

Good luck with it all.

Dickspanner

[Cableguy]

There's a list of gearbox codes with all the specs of final drive etc on the rjes site. Loads of useful links too

[nicko868]

hi
thanks for all your replies the engine has allready come out of a bus so it is the complete kit , the wiring harnes just needs extending and then can be cut and grafted to where it needs to go. my main issue now is that i have a ABD gear box at the muinet and i have looked on that site that you have sujjested and i dont think that will be any good for the engine i want to put in, do you have any sujestions of what gearboxes would be idea to put in ? as i dont reallyhave the money to get one custom built . cheers

[dickspanner]

A lot of people recommend the DK box however, others say there are better out there.

DK boxes are pretty rare and if people have them are reluctant to part with them. I purchased one for my Cosworth conversion but run another recon box at present so it is sat on my shelf incase the current one goes bang.

My crewcab is up for sale soon and I was just going to let it go with everything else.

Keep me posted on your search for a box and if you hit a stone wall PM me.

Dickspanner