1.6 4 speed carb to 1.8 GTi EFI 5 speed conversion

Hello,

Just hypothetically speaking I have a mk1 caddy and seen a 1.8 GTi engine, box and loom for sale at a good price and thinking they should just swap out and in fine.

I've been looking on the search, it seems the wiring's almost the same so no issues there, I'll need to change my 4 speed box mount for a 5 speed one but a couple more questions if anyone knows please…

• Would my 1.6 radiator still be OK with the 1.8GTi engine? -would the water pipes etc line-up OK as well
  My 1.6 is a 4 speed -would I need a 5 speed gear stick mech etc also or is it just the box which is different
  Would I need to change my fuel pump or could it run on the 1.6 one (maybe change for a GTi one at a later date)
  I assume drive shafts would swap over OK with no mods[/list:u]
  
  …I'm working away from home at the moment but this seems a good opportunity to swap engines for not much outlay so am asking a few questions with mechanic friends if they could give me a place and a hand to swap over -should really only take a day I think.
  
  …Can anyone think of anything else which I'd need to look at please.  I'm going to bounce these questions off Crazyquiffs and on the caddy forum as well as I might have to make a quick decision if I want to go for this engine.
  
  Thanks,
  
  Richard

1. not sure, depends how wide it is? if its got the 2 rubber flaps oin the rad housing its good enough, if not its too small ideally you want a 1.8 carb/gti rad, shroud and pipes
2. need 5 speed gear stick bits but i think you can do some trimming to get the required movement for all 5 gears, various bits in the bay are different too.  For an easy life I'd get a complete setup front to back
3. no, you need a complete GTI electronic fuel pump & lines setup front to back. carb has a mech pumnp on the engine and it is incapable of supplying the pressures needed

Thanks rubjonny.

• according to vagcat the radiators for both engines look about the same size so it looks like it can be swapped and will run ok
  yea, I'll just source a 5 speed linkage set-up -less hassle on the driveway during the swap!
  I'll need to source a fuel pump as you say -I'd be tempted to go for an in-line fuel pump mounted somewhere convenient (seems the easiest way of doing it prov I match the flow / pressure[/list:u]
  
  I've actually been offered twin weber 40's for it also, but just can't see the point of going from EFI back to carb.  Thing is this engine's got 109,000 on it and my original 1.6 has 81,000 so to be honest that's putting me off at the moment although I know VW engines are good for high miles IF looked after.
  
  I need to have a good think about this rather than doing what I normally do any letting my heart rule my head!
  
  (how do you get the list function to work by the way?)

hi i wouldn't trust vagcat for measurements best thing is a tap measure

as for the GTI which car is it from ?

That's a good point re vagcat! -it seems to be OK as a starting block though.

I think it's from a Scirocco (I assume that's what a "roco" is?) -I'm waiting to get some pictures etc and some more details.

I went to see my mechanic friend last night -he was on nightshift but not exctly busy so he's been filling me in on the old VW's.  He took an early golf down to Africa on a charity race last year.  This is who I'd get to help with the conversion and he knows VW's inside out.

the reason you need to know the engine is you will need to know weither its a electronic fuel injection or mechanical fuel injection

you will need to add an electronic fuel pump compared to the mechanical one you have on your engine.

one thing i do remember is that a 2liter engine the sump sit to low not sure if its the same as the 1.8

you need a proper k-jet fuel pump setup, there are very few aftermarket ones that can supply the correct pressure, and those that can are usually very expensive yet are basically the same as an oem one.  You must fit the proper accumulator as well, otherwise at worst the engine wont run right, and at best warm starts will be very difficult.

If your car is a carby atm what you can do is fit a lift pump and reservoir from a late MK1 cab/scirocco, this will allow you to keep your old fuel tank.  then fit the main pump and accumulartor either from the same car if k-jet, or oem MK1 GTI items.

crazyquiff can do new main engine bay flexi lines, 2nd hand ones in good nick are hard to find

There's a lot of parts to change. If the engine is from a Scirocco it will be K-Jetronic mechanical fuel injection, not EFI (electronic) and it will need 5 bar fuel pressure or thereabouts, so it makes a difference, so you need to change or customise the fuelling system. Caddys have different tanks to other mk1s so you'd need to adapt parts to it, not sure if a lift pump from a Mk1 Golf convertible or Mk2 Scirocco would just drop in?

Gearbox is swappable but you'd need the bracket on the steering rack too; and other smaller parts to do with the linkage.

1.6 carb radiator is probably 430mm and the GTI one 525mm. By all means, try the smaller radiator with the larger engine, but I'd be swapping them too. Also, take note of the oil cooler arrangement - I assume the later GTI engine from a Scirocco would come with an oil-water cooler, rather than the air-oil cooler of earlier ones. I'd stick with this but with the rad upgrade and oil temperatures should be okay.

Also in terms of handling and braking, 75bhp –> 112bhp is a fair old jump, so I'd not neglect the brakes, suspension, wheels and tyres. Don't forget you'll need to insure it at the end of the day, your insurance company might not accept mods, or insist on an engineering report, or load your policy excessively etc.

Also dont forget to obtain a receipt for the engine. In theory because the capacity is going up, you don't need it, but the DVLA ask for it in all engine number swaps on the V5. It will save a lot of hassle to have one.

I haven't needed a recipt to change the engine number on a V5 before but I have heard it's needed if it changes any emissions checks at MoT time.  I wouldn't buy something like an engine without some paperwork anyway.

its a recent change they brought in, now you need this even if the emmissions levels arnt effected, also even if the size goes down. right mare.
thankfully I got 2.0 on the V5 before they made the change, but i put a 1.8 back in temporarily and they wanted me to jump thru all these hoops, so i thought fk em why bother if they're going to make it hard, was only going to be for a couple months anyway!

fair enough rubjhonny, I've aleays stated to other folk that if it's a sale like that you need a recipt, preferably also if the cars being broken for parts (scrapped) then the paperwork ststing that also to keep your nose clean.

Guys, I'm new to VW's but not modifying.  Insurance etc etc etc no worries at all though I know there's a few toe rags which crop up again who don't declare.

To be honest I think I'm going to cool-off this for the moment because I'm out my depth familiarity wise with VW mechanics (though blissfully simple to work on!).  The caddy's a pain in the ass as it is -I mean I can't go anywhere without getting into a conversation!  Stopped at BP in Inverurie after work tonight and guy showed me his pics of his mint black mk1, then when I went back on the fourcourt had another chat with the guy next to me filling up!

I have a plan for carbotech brakes first because the caddy ones are pap and I know what a transformation they made to one of my other cars.  I'm running an axle flip and coilovers on the front anyway -but you guys are absolutely spot on -allot of supporting mods to accompany.  Just annoying as I've changed job.  If anyone's changing pads and has a buck-shee set of backing pads can they let me know please!!.

To be honest, I might do smaller, quicker jobs first before I worry about engines.  I have no complaints about the engine I have -it's always that little devil on my shoulder which I have to keep back.

Thanks very much for the advice!