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Subaru legacy bh5

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Hi all I'm just after some advice, I have a legacy bh5 that's in a stock automatic form, I want tk put a link on it as I have on my other cars, but don't k ow if it is compatible with the auto. Any views?? 

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What engine does your car have? non turbo or ez30 - maybe. single turbo conversion - maybe. factory twin turbo - controlling those would be a problem.

Apart from that - these cars still had separate TCM's so theoretically it could be done. There are only about 10 wires that touch both the ECM and TCM in factory trim - TPS goes to both, RPM goes ECM-> TCM+tacho etc, MAF/MAP says it goes sensor->ECU then separately ECU->TCM but I seem to recall some of them go direct to the ECU&TCM from the sensor, and if not you could probably splice it to do this. Then there are the 3x torque control wires. You'd need to figure out whether the signals to ECM->TCM or the other way around, and whether the TCM actually needs them to function. I suspect you could do it but you might trash the transmission pretty quickly if you dont have the torque cut request working properly.

Its certainly jumping well into the deep end and wouldnt be an easy swap.

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Thank you for the quick response. I am looking a parallel turbo setup, as I think it would be easier to control, I want to keep auto as a road car but like all my cars I charge it to manual eventually lol. Well I need to do a bit of homework on the wiring and what commands what but really appreciate it. 

Kind regards bret 

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considering an ECU is probably 2k and a lot of planning, and a 5 speed conversion on 1 of these is typically under 1k in parts (at least in NZ) and can be done in a weekend, id suggest the manual conversion first and just skip that whole auto trickiness.

Off the top of my head these already run a single wastegate and BOV so swapping it to parallel turbo means yes it would be simple enough to control, but with factory sized turbo's, you wont see useful boost until about 4-4.5k rpm which is kind of a big drivability problem. source: I have a stock one as a daily driver and the factory twin turbo control is mostly vacuum actuated and can get "stuck" running the turbo's in parallel for 10-20 seconds if you change gear just as the second turbo comes on - for these 20 seconds you can only get about 2psi of boost below 4k and it feels really flat off boost.

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