M21 turbo specs

[cetanefreek]

I have been working with diesels most of my life, but am new to the BMW world, I am looking to crank up my 524td but need a starting point to know where I am upgrading from.

I know my turbo is a T-3 but can anyone tell me what trim it is?

[Brad D.]

You might find some info in this thread.
It appears that it is a t3 50 trim which would have this compressor map -
50 Trim

[cetanefreek]

Thanks a lot! that's exactly what I needed, I'm going to try to get dyno numbers after every modification, and will post what I find.

[Brad D.]

Thanks a lot! that's exactly what I needed, I'm going to try to get dyno numbers after every modification, and will post what I find.

Definitely post dyno plots, as a well documented TD power build will be interesting to see.

[///ARINUTS...]

You would want something that spools much quicker and will provide as much boost as your fuel can support.

GT2056V or GT2256V

variable nozzle turbine technology.

[slave2school]

I'd like to g VNT...sigh...someday. Just a it harder to rig up a control system for it though

[cetanefreek]

well I put it on the dyno for my baseline, all I've done at this point is adjust the fuel pin to max travel position, it netted 74 rwhp and 115 ft/lbs torque, on a dyno dynamics dynamometer (shows 15% lower than other dyno's average)


my next question for all of you with the knowledge, is the M21 exhaust manifold bolt pattern the same as the M20?

[Mark 88/M5 Houston]

my next question for all of you with the knowledge, is the M21 exhaust manifold bolt pattern the same as the M20?

Yes.

[muuris]

You would want something that spools much quicker and will provide as much boost as your fuel can support.

GT2056V or GT2256V

variable nozzle turbine technology.

Even with stock distributor head on the pump I'd say the gt2056v is kinda small. I had Audi vnt20 on my M21 some time ago and it just couldn't keep exhaust gas pressures down. Surely it boosted up nicely and the torque was way different than in stock M21. If one wants a vnt turbo, one should get the gt2556v in the first place. Bigger is better, because spooling up is no problem with vnt.

[Brad D.]

my next question for all of you with the knowledge, is the M21 exhaust manifold bolt pattern the same as the M20?

Yes.

It is a bit different. It will only fit on an m20 with modifications to the bolt holes as they don't directly line up. Alot of porting is also required as the port floor of the head winds up with a step on the manifold.

[cetanefreek]

in light of that, looks like the stainless header I was given will be re-sold, unless I keep it and weld on different flanges.

anyway, the re-ground cam has been installed as well as the rebuilt injector pump and the cleaned and pop-tested injectors, now just waiting on some glow plugs and exhaust manifold gaskets, although it seems that I'll have to buy a full head gasket set, haven't been able to find them outside of said set.