Mk2 -> GT conversion

GroovyCarrot · Post by **GroovyCarrot** » Tue Dec 13, 2005 9:21 pm

I'm thinking of converting my old breadvan to a GT next summer, the old 1043 is smoking a bit now and it's a bit frustrating not having any power, and the new gearbox is showing signs of not having enjoyed a hundred mile trip without oil, so I figured I'd just do a straight swap for a GT setup. I was just wondering if there's anyone on the forums who's done this and can offer any advice.. potential pitfalls, necessary kit, likely cost etc.

GroovyCarrot · Post by **GroovyCarrot** » Tue Dec 13, 2005 9:23 pm

It's a 1986 mk2 breadvan btw, post revisions (hydraulic tappets and all that stuff).

Mk2Adam · Post by **Mk2Adam** » Tue Dec 13, 2005 11:04 pm

Great to here you've still got plans for your old mk2 breadvan, i thought u'd chucked it to be honest as i hadn't heard anything from you...i'd like to hear the answer to this too coz i'd love to do a GT conversion to my 1litre in about a year.

mk2keel · Post by **mk2keel** » Tue Dec 13, 2005 11:19 pm

i havnt done it myself but from what i have heard you will need, the engine, gearbox, ecu, wiring loom, fuel tank and new fuel lines. Thats only a rough guide so dont quote me on it.
There are a few people about who have done it though who could give you a much better idea of what is needed.

hardhitter · Post by **hardhitter** » Wed Dec 14, 2005 12:04 am

I don't think it's too hard being a later Mk 2. Make sure you get the hard plastic fuel lines which are needed to withstand the fuel pressure. I think the engine bay wiring loom is pretty much plug in and play apart from one or two wires. You need to include the wiring for the inline pump too.

Nothing you can't sort out I'm sure.

GroovyCarrot · Post by **GroovyCarrot** » Wed Dec 14, 2005 1:23 am

Mk2Adam wrote:Great to here you've still got plans for your old mk2 breadvan, i thought u'd chucked it to be honest as i hadn't heard anything from you...i'd like to hear the answer to this too coz i'd love to do a GT conversion to my 1litre in about a year.

Yeah, I've not been around too much recently because I've been at uni, didn't take my car with me for financial reasons. I've got a long summer holiday though so I'll be getting it back on the road for that, just formulating my plans well in advance

Cheers for the help guys, I'll give it some thought. Any ideas on roughly what I'd be looking to pay for a half decent set of parts?

Gareth_GT_Hatch · Post by **Gareth_GT_Hatch** » Wed Dec 14, 2005 6:30 am

Ive done a mk2 to fuel injection conversion as you may know GC. Ive got a few pointers for you in terms of wiring and such like. Dropping the engine in is the easy bit as far as a veteran like you is concerned.

Fuel Tank - Ideally you want a mk3 one as the internals differ to a mk2 slightly. Its ok to use a mk2 one though, you can join the outlet and inlet together on the bottom of the mk2 tank.

Fuel lines - You need everything from a mk3 for this one, Including the brackets that run under the car and around the rear axle to the fuel pump/accumilator/filter housing. You dont have to use a GT car for a donor as far as the fuel lines go, but ideally youd have the GT inline pump for the higher pressure it puts out.

Exhaust - I used a full mk3 system on mine (decatted) to incorporate the lambda probe. Alternatively you can use a mk2 system, you just need to add a threaded hole for a lambda proba on the downpipe. If you do use a mk3 system its best to do the lot; from manifold right up to backbox. (you may have to shorten the tailpipe)

Additional wiring - Again ideally you want a donor car to take the fuel pump wiring from. I saved everything from my scrapped GT so I had all the bits I needed fortunately. The wiring is really simple so theres not a great deal of hassle involved in removing it. Basically theres 3 extra wires on top of what the mk2 has; Two of which are a +ve for the fuel pumps and the third is an earth for the inline pump (the tank pump can use the earth of the fuel gauge sender) The +ve wire(s) are red with a yellow stripe and they both can be connected to the loom via the additional fuse that mk3s have (Yellow one that is part of the fuel injection loom - which clips above the fusebox)

Engine Bay Wiring - You need EVERYTHING from the GT that plugs into the fusebox, just the ECU loom wont do.

Engine bay wiring differences. On mid mk2s alot of the plugs are different to mk3s, they still use spade connectors instead of the more modern plug design. The plugs that are different are:

- Blue and Black temp sender (not a problem for you as you will get the right ones with the GT engine)
- Horn
- front indicators (side repeators are fine)
- Sidelights
- Reverse switch
- Starter motor solenoid wire (Should come with the engine conversion)
- Oil pressure switch wires (where these connect to the rest of the loom is where they differ, you should get this with the conversion anyway)

All of these parts can be sourced from late mk2s (whenever they switched over to having plastic timing belt covers is when they started using the more modern connectors. G reg onwards or there abouts I think.)

Theres a couple of other small differences worth mentioning:

- Expansion tank level sensor might be needed if your car doesnt have one. (late mk2 expansion tank) This wasnt a problem on mine either because it had one and the plug was the same, or it didnt have one and I had a late mk3 loom which didnt have the plug anyway.

- You need the GT radiator fan as its two speed and the plug on the loom is different. You probably also need the temperature switch on the radiator. You can retain the original radiator setup though for the most part. (I think theres a slight difference in the return for the expansion tank so you might want to use the mk2 thermostat housing and join the two outlets for the inlet manifold together)

- Windscreen washers; If like my ranger your car has 2 tanks, the wiring on the GT loom needs altering slightly. The deal here is on later ones the pump goes in two directions, forwards to do the windscreen and backwards to do the tailgate, This is done by having a switched live and earth. Now for some reason if you leave the GT wiring alone the front washers wont work if you have the separate tank setup. But if you replace one of the wires (I forget which) with an earth it works fine, and doesnt effect the rear wiper operation.

- The alternator bracket and alternator are sllightly different but it only matters if youre swapping alternators between the two engines (just swap the bracket with it)

- Last thing: For the rev counter to work you need to add a wire from one of the terminals of the coil to the back of the clocks. I cant remember right now which pin it is but its around pin 5 or 6 IIRC (red wire) As for whcih coil terminal it is just use trial and error.

Think thats it! Good Luck!

hardhitter · Post by **hardhitter** » Wed Dec 14, 2005 9:48 am

Not all rad fans on GT's are twin speed, for the record

If you can get a complete GT for the conversion it's best.

GroovyCarrot · Post by **GroovyCarrot** » Wed Dec 14, 2005 1:11 pm

Blimey, that's a lot of odd little bits need changing. Guess I'll just have to find someone scrapping a complete car really, although I don't know where I'd keep the donor car, space is a touch tight here. I'll give it some thought though, might have to find myself a lockup to keep it in or something. I've been planning to do an injection conversion for quite some time though, so I really ought to go the whole way if I can.
Cheers for the help again

DanDiesel · Post by **DanDiesel** » Wed Dec 14, 2005 7:59 pm

just thought i'd add that theres a gt engine up for grabs in the for sale section! Â£350 no offers

SpikeyG40 · Post by **SpikeyG40** » Thu Dec 15, 2005 5:35 pm

sounds like an interesting plan GC! i would imagine u would be looking at uprating the brakes due to the lack of servo! what were your thoughts on this?

i spose if u get a gt then the gt brakes it is, but would it be worth trying to get hold of some G40 brakes? this would aid in improvement as i no what the mk2 brakes are like!

by the way gareth! great info, i didn't realise there would be so many small bits that could be missed!

GroovyCarrot · Post by **GroovyCarrot** » Thu Dec 15, 2005 10:39 pm

DanDiesel wrote:just thought i'd add that theres a gt engine up for grabs in the for sale section! Â£350 no offers

Cheers for that, I'm keeping an eye on it.. I've got time to kill so I'm going to wait around for a bit, but if it's still hanging around a bit closer to the time I might just go for it.

SpikeyG40 wrote:sounds like an interesting plan GC! i would imagine u would be looking at uprating the brakes due to the lack of servo! what were your thoughts on this?

i spose if u get a gt then the gt brakes it is, but would it be worth trying to get hold of some G40 brakes? this would aid in improvement as i no what the mk2 brakes are like!

by the way gareth! great info, i didn't realise there would be so many small bits that could be missed!

GT brakes are the same as my brakes now, apart from the servo which is standard on mk3's and unfortunately isn't possible to fit to a mk2 due to the shape of the bulkhead. I've toyed with the idea of fitting a remote servo before, but I don't trust myself enough to start re-routing the brake lines in order to fit one, so I think I'll just have to use a bit of welly on the brakes. I've got a vented disc setup in the shed though, so that might go on to help things a bit.

hardhitter · Post by **hardhitter** » Fri Dec 16, 2005 11:57 am

I sold a GT setup last week for Â£180 !

It had the engine, box, wiring loom, ecu, ancills and fuel pump. Granted it needed a timing belt, water pump and clutch but for that money, who can complain.

I may have another 3F engine for sale in the new year, rebuilt and previous low mileage.

GroovyCarrot · Post by **GroovyCarrot** » Fri Dec 16, 2005 5:07 pm

hardhitter wrote:I sold a GT setup last week for Â£180 !

It had the engine, box, wiring loom, ecu, ancills and fuel pump. Granted it needed a timing belt, water pump and clutch but for that money, who can complain.

I may have another 3F engine for sale in the new year, rebuilt and previous low mileage.

That's pretty decent.. and it's not like it's hard to do the belt/pump/clutch while it's on the bench anyway. Wish I'd known about it! Still, I'll keep my eyes open for any bargains, I've got until the summer to work out what I'm doing and I'm perfectly happy to do anything that doesn't involve bottom end work (bad experience with that, and it doesn't seem very easy to get hold of 3F piston rings).
One small problem is that if I get it before the summer, I can't travel very far - driving my mum's Shogun during the holidays and that thing drinks diesel like water

Might have to wait until the Polo's back on the road before I consider collecting from any great distance.

Gareth_GT_Hatch · Post by **Gareth_GT_Hatch** » Sat Dec 17, 2005 9:16 am

Dont let the big list put you off. alot of the things on there are 5 minute jobs, although personally I dont think I would do it again to an early or mid mk2, certainly not on my derby anyway, I just dont think fuel injection is the right way to go on it. I wouldnt mind doing it to a very late mk2 though, preferably another ranger, but as late and low mileage as poss (but also preferably still a wolfsburger)