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Engine swap for dummies (D7F -> D4FT)

CreweTube

Well-Known Member
Hi all,

Looking to build up my knowledge (forewarned is forearmed or something) before taking the jump into doing an engine swap in nearish future, watched a few YT videos for the process in general but wondering if anyone has a good resources for this particular swap in particular (D7F 1.2 NA -> D4FT 1.2 Turbo) in a Twingo Mk2.

At a very simplistic level I understand the actual physical process of draining fluids, disconnecting wires/lines then hoisting engine then reverse to refit, but a lot of my questions come down how everything goes back together as I'm assuming there are bits that won't just plug and play:

  1. ECU, is this on the back of engine or the one attached to the battery box (or both), presume this needs switching too?
  2. How does the key/immobiliser factor in to all of this if at all?
  3. Dash instrumentation will work fine again?
  4. Given both engines were standard fitment, hoping driveshafts will slot back in fine..
  5. Presume new exhaust will be required for completely different flow requirements

The car is road legal at the moment and whilst it probably wont stay that way long term, anyone been through the process of updating DVLA and then MOT/VED impacts as heard some horror stories.

Project thread is here for background:
 
This is a pretty big undertaking despite how simple it looks when using parts rather than a complete car. Looking forward to the updates though (y) ill help where I can,

1, yes you WILL need to use the d4ft ecu, chances are you will grenade the engine without it. The loom will also be different. With the GT loom the ecu will be located over by the battery. There are extra sensors and controls you will need to run the engine too that aren't present on your current loom. You can disconnect the whole loom from the fuse/connection box on the right of the engine bay.

2, the immo information is stored in the body control module, this then checks that it matches the info on the ecu start up. If you change either/or independent of the other you will be stuck again. You need a matching key/body control unit and ecu. You may be able to virginise the ecu to accept a new immo code but im unsure on our ones tbh.

3, id assume the dash will work still, they are pretty basic.

4, id assume the same with shafts. that said it depends on the gearbox type too. the twingo is a funny one and was fitted with 2 styles of gearbox and shaft as far as i can see. One type, the older have a spider that goes into the diff on the pass side and sleeve on the other. the later style as used by the gt has a gearbox that accepts a shaft into both sides of the box.

5, the fitment of the exhaust will be different, that said the stock GT system is probably only 1.75 inch so not huge though its nearly a straight through system with just backbox.

Engine swaps to a different size/code aren't a massive headache as far as i know. I should probably sort it myself lol
 
as a side note, talking from experience id buy the cheapest smashed up but running GT and have it for parts if you are defo set on upgrading the current chassis
 
Looks like the gearboxes are different between the D7F and D4FT (I think the 800 is the one) so will see, hopefully getting the engine/gearbox and connected bits as one lump if I don't get an entire donor car before.

1636450500379.webp
 
if you have a JB1 box fitted im sure its the earlier style shafts. Also then next potential issue, im pretty sure the JB1 was a cable operated clutch setup and rod shift? the JH3 and JR5 are hydraulic and cable shift.
 
Hmm, quick google took me to clio land which used JB1 and JB3's as the uprated model so might have to use that if I dont swap everything.

raw
 
I've been mulling this over in my head you know... I know its a different direction from a small turbo engine but I think a n/a engine might be a better application and approach for the parts you have kicking around already..... you would have to confirm a few things, mainly with the ability to map your current ecu, but you might be able to sling an rs133 or clio 172 engine in there and run it on the stock ecu, would negate issues with the immobiliser if so ..... just an idea
 
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Strange that, I was having the same thoughts. I contacted Chris at EFI-Parts last month about just doing a quick dyno run to see how (little) power it actually has and also for him to look at the ECU whilst there as he's never had anyone with a D7F turn up, might be a good idea to do whilst there anyway.
 
Great minds and all that :D if Chris can map that ecu that would save loads of agro, worst of it being the loom to deal with afterwards as you wont want the ecu where it currently is, re looming isnt too hard though.

You will more than likely loose/not have vvt control on your ecu but the cams could be run locked in position. Cheap gains, parts bin building, I'm getting into this build (y)
 
Thanks to @YamYamRob doing some advance scouting for parts for himself it looks like early Jan will be sourcing:

  • D4FT engine plus gearbox (with knackered turbo, allegedly mapped to 130hp with zero proof or evidence so expecting nothing)
  • Loom
  • ECU & Body Control Unit
  • Keys and ignition barrel
Anything else to grab whilst there to make life easier? Sadly no exhaust with it.
 
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Driveshafts are gone but good shout on the hubs, had mentally put all the rads in with the engine but will make a seperate note for the. Probably get the fuel pump too as my one is definitely original on 122k and not sure whether they changed them too.
 
Ns driveshaft is still there, os hub and driveshaft have gone.
According to haynes manual for clio 3 tce the tce pump flows more than a normal 1.2.
Also i have a spare td025 turbo.
Think the remap on it is a roadside remap, itll have some power gain but what is anyones guess.
 
Updated list (in red) for aquirring from the donor car next week:
  • D4FT engine plus gearbox (with knackered turbo, allegedly mapped to 130hp with zero proof or evidence so expecting nothing)
  • Gearbox cables (as my box is rod) and anything else assosciated to it
  • Radiator/Intercooler + pipework
  • Loom
  • ECU & Body Control Module
  • Keys and ignition barrel
Anyone know where the heck the Body Control Module is located in a Mk2 Twingo, google tells me all about where it is in the Clio and sometimes called UCH but cant find much info about the Twingo version. To my knowledge it handles all the immobiliser related stuff and cabin electronics which needs to be kept in sync with the ECU/Key change anyway, this is what people on ebay are selling an an ECU Set:
1641576886729.webp

L to R: Keys, door barrel lock, ECU, BCM, Ignition barrel
 
More updates as D-Day becomes closer

  • D4FT engine plus gearbox (with knackered turbo, allegedly mapped to 130hp with zero proof or evidence so expecting nothing)
  • Gearbox cables (as my box is rod) and anything else assosciated to it
  • Intercooler + pipework
  • Loom
  • ECU & Body Control Module
  • Keys and ignition barrel
  • Fuel Pump
Might also just take whatever calipers/drums/hubs/driveshafts are left as its getting scrapped after so can be spares for me.
 
More updates as D-Day becomes closer

  • D4FT engine plus gearbox (with knackered turbo, allegedly mapped to 130hp with zero proof or evidence so expecting nothing)
  • Gearbox cables (as my box is rod) and anything else assosciated to it
  • Intercooler + pipework
  • Loom
  • ECU & Body Control Module
  • Keys and ignition barrel
  • Fuel Pump
Might also just take whatever calipers/drums/hubs/driveshafts are left as its getting scrapped after so can be spares for me.
Alternator and brackets, all coolant pipes inc rad.
 
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