Working out a Turbo's vital stats..

Post Thu Jul 17, 2008 4:42 pm

What actual parts of the turbo do I need to measure to work out the trim, A/R etc. I know I need to remove the compressor/turbine housings to do so.

I've got this little lump (Holset HX50) to attach to my M30B35..

Post Thu Jul 17, 2008 5:11 pm

Take off the housings, measure both wheels, inner and outer sizes.

mine is 55/82 Cold side and 67/63 hot side

The housing size is printed on the hot side housing, there should be a few numbers, two are what you need.

From the compressor sizes you can get the trim.

HX50 are usually massive and run on 10/15 litre diesel engines, still I've seen them on M20B25' also.

When you now what you have I'll email the details to the swed's and ask there opinion, unless IXER ( Mattias ) notices this thread first.

HTH, Fozz

Post Thu Jul 17, 2008 5:31 pm

Cheers fozzy I have seen a couple of the swede sites using this turbo on M20B25's M30B30's etc

I managed to get the cold side removed the other day and it was 67/98 +/- 1mm but have not been able to get the hot side off, I undid the bolts but it didn't want to budge, does it just need a tap to free it up. The inner measurement is 76 again +/- 1mm I'll try again to get the hotside off at the weekend.

The only numbers on the hotside are: 3537412 - 02 and then 25 129 T2

Would the T2 be flange size?? I thought it was only T3/4...

Sorry for all the questions, this whole project is going to be a steep learning curve

Post Thu Jul 17, 2008 5:51 pm

HX50, that'll be good for inter-galactic travel

Post Thu Jul 17, 2008 6:04 pm

E30BeemerLad wrote:HX50, that'll be good for inter-galactic travel

Should be a giggle going to run low boost around 7-8psi and then rebuild the engine at some point with an MLS headgasket and some ARP head studs, this is assuming the stock gasket/bolts will take 7psi of boost?? if not then that'll be done first.

This project will most probably take around a year as I'm new to turbo's, megasquirt etc so will take my time and do a lot of digging for info, learning new skills etc..

In this current financial climate I'm going to be sensible and off set all my old spares to pay for it... not like my youth were I would just slap it all on a credit card and have it now!!

Post Thu Jul 17, 2008 8:53 pm

Hmm thats a nice small HX50, comp trim is about right, hotside is almost defo too big, will want 22cm/3 max I'd suggest.

T4 split pulse flanged too, the assy number on the comp housing will give all the required details, BTN may be able to assist there.

to pop the housing, pop the turbine housing on the gas stove( if avail ) for a few mins, it will draw the heat fast and pop apart without worry after a few mins, tapping it off is OK, but it must come square ! otherwise its poss to chip the turbine wheel.