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740 B5234T with BMW DCT gearbox

[Max]

New member
Joined
Aug 22, 2020
Hi all!

First I would like to excuse my grammar since I am not native in english.

2019 summer I bought a 740 with B5234T engine and GS6-37DZ gearbox from Sweden. It has forged engine with Precision 6062 gen2 T4 single scroll turbo. Brakes are stock in rear and V70R at front. Car was tuned in AG's I Norrk?ping and made 503whp.

Drove it whole summer of 2019 and half of 2020 and got tired of changing gears when eating icecream at the same time so I decided to do something for it and bought 7 speed double clutch gearbox from E9X M3.

Adaptor plate was found from Domiworks. Gearbox mount and driveshaft were fabricated. There was plenty of job to do even the plate was plug and play.

Now therebare only paddle shifters and some minor electrical work to do before testdrive.

I wasnt planning to start thread but many people from facebook. Requested it.

Will post pics once I figure out how to attach those.
 
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What are you using to control it? I saw MaxxECU can control one.

Jordan

I use Maxxecu Race and their DCT harness. It is not plug and play but pretty close. Paddles are from GT86 Toyota.

Here you have pic of the adapter.

ACtC-3djWx-BIowSYpiCmgnLsZNsWjPqWNp1Ddnj2yF_NRBEk_A6MfZVlQDzi9pX8kS1GzXi2LsNElmgSPnHqFlGO64pf4Px3ACu_tzMugu4dTJGUTHuiQ7dIZX6PmlUa0mCziwOjCy9KJ43xwdUh0z9h3OjXQ=w945-h1993-no
 
Here it is installed. Btw the downpipe is 4".
Oil lines are installed aswell. Made the rear support for gearbox.

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ACtC-3fu9vqHIlL8RfjNSVtyHcTO9xxyhperiqrVo6PQn5QOHQoSmk7pCFag0B4UN3jjf2Q2nVMjIeh1L4gm_wRBPf6Ae9mFI97nnyB8tCl97JPM23uLAbfUrOAA6Qtu5n-Bp0vjo_QpMa2NzdZgvw5pDIL0Bw=w1080-h488-no


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Tyres are Toyo R888R, 225/45ZR17 front and 255/40ZR17 rear.

The car has original turbo camshafts which are limiting factor in this stage. Friend of mine has prepared dual vvt cylinder head for me with bmw m50 valves and 10.8/280 cams. Once the dct mod is ready I will swap the head. Expecting 100hp more.

Car has made 6,8s from 100 to 200km/h.

Pic of engine:

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DCT quick info

- My gearbox is from E9X M3 BMW
- Maxxecu supports only E9X can protocol at this stage
- Original gear selector and drivelogic button are required
- You can use V1 Maxxecu with DCT but some can addresses will interference with drive by wire module i.e problems can occur. Will work if DBW module is not used. I am using Race which has internal DBW support so no problem with that.
- Domiworks is selling the adapter kit. Expensive but best. Worth every dime.
- Minor modifications are required for the bell housing. Domi includes a note with the kit
- With ASS engine mounts on 740, minor firewall hammering is required. No cutting or welding on body.
- Different starter motor is required (info on Domiworks website)
- Electrical work needed: wheelspeed information, brake switch, OBD plug to update gearbox, paddle shifter wiring
- Coolant for heater core has to be taken from another place since adapter interferences with the plug on the block
- Driveshaft has to be modified, rear support for gearbox has to be manufactured
- Oil cooler and lines for gearbox
- Maxxecu does not support park lock feature, park lock delete kit has to be installed
- Different crank trigger has to be used (included in Domiworks kit)
- Clutch pressure is around 17 bar, coolant circuit pressure is around 5 bar. GTS firmware is needed to get the full pressure.
- Stock clutches will hold around 750 Nm with stock clutch pressure and 1000 Nm on GTS firmware (more clutch pressure)

Some manual work is required :)
Hope I will get her running next week.
 
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Tyres are Toyo R888R, 225/45ZR17 front and 255/40ZR17 rear.

The car has original turbo camshafts which are limiting factor in this stage. Friend of mine has prepared dual vvt cylinder head for me with bmw m50 valves and 10.8/280 cams. Once the dct mod is ready I will swap the head. Expecting 100hp more.

Car has made 6,8s from 100 to 200km/h.

Pic of engine:

ACtC-3dZckNOj_-yRC813T5xlNf3Blm4VMf3YBcczUSkjFs1PdHKAfX47sQS6MuIwDxnK2Yx8rOu2ls50kS_-G_9Ku2ZHypbkCmI-tG__8CcRCeD1cM5FTIrxknjLFDx0qxUA9tSHSNLBYOrfqiOjnrPppYhAw=w1080-h513-no

Awesome!

Care to share where that intake manifold is coming from?

Was the block shimmed between the bores or did it get a block guard to close the deck, or both?
 
Intake manifold is done by previous owner.

Shims between bores, no girdle. Personally I believe girdle will not give that mouch support cause original sleeve is fragile and will crack under the girdle. Darton sleeves or D5 block is the way to go.
 
Intake manifold is done by previous owner.

Shims between bores, no girdle. Personally I believe girdle will not give that mouch support cause original sleeve is fragile and will crack under the girdle. Darton sleeves or D5 block is the way to go.

You have the more solid 81mm bores on the 2.3L so yes the block guard helps.
 
I dont see the benefit, it will crack just a bit lower with girdle.

DCT swap is now mechanically and electrically ready. First test drove was done today. Next we will tune it, there are quite a bit pf parameters that needs to be adjusted.
 
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