Holset m20 turbo Q's

[ST1G]

So I decided a little bit ago that I want to do an m20 turbo build as I'll be getting my brothers Golf to drive for the next couple years and will have time and hopefully the coins to build up a turbo.

I am now in the process of finding a turbo and assembling parts. I was thinking a Holset HX35 or HX40 but recently a WH1C popped up. I've read they are very similar to the HX35 and use the same housing size and impeller size? I'm wondering if this would be a good turbo, or if I should try to find a HX35-40?

I've also ready Holsets are rather easy to rebuild fairly cheap. and was wondering If this would apply to this turbo.

I'm waiting for my Maximum Boost book to get here so I can read that prior to starting, as I've read that's invaluable.

[saturnv7890]

I am no expert by any means, so I'll let others chime in, but I am running an H1c. It spools wayy late because the exhaust housing is way too big for the boost level I'm at (7 psi - wastegate issue, should be 10)

There are many different exhaust housing sizes that all fit on a h1c's and hx35s. So with the right sized exhaust housing, an h1c will do just as well I would think!

I'm running a 16cm exhaust housing, 7 psi on a 2.7i makes this dyno chart:

http://i.imgur.com/hawkToM.jpg

I think a 12cm housing would be much better suited, and an easy swap to do. Depends on what you want

[ST1G]

I am no expert by any means, so I'll let others chime in, but I am running an H1c. It spools wayy late because the exhaust housing is way too big for the boost level I'm at (7 psi - wastegate issue, should be 10)

There are many different exhaust housing sizes that all fit on a h1c's and hx35s. So with the right sized exhaust housing, an h1c will do just as well I would think!

I'm running a 16cm exhaust housing, 7 psi on a 2.7i makes this dyno chart:

http://i.imgur.com/hawkToM.jpg

I think a 12cm housing would be much better suited, and an easy swap to do. Depends on what you want

Thanks for your reply!

Yes, I did some more reading and it seams that the H1C is pretty much the same as the HX35 but spools later like you said.

I'm not looking for crazy power (yet) and am going to do the 2.7i as well, but that might change.

Looks like rebuild kits are about $60 and I can get the turbo for about that. Its an 8 blade from a 1994 cummins.

[saturnv7890]

Check out exhaust housing size, shoot for 12cm if you're not looking for crazy power. You can change it later if your EGTs get crazy.

Once again I don't know much about turbo selection so let others chime in before you do anything

[Farbin Kaiber]

I'm guessing you have gotten cracked out on kamotors build thread already, right?

[ST1G]

I'm guessing you have gotten cracked out on kamotors build thread already, right?

Actually no, I've read that thread, but until you mentioned it I didn't even realize that was the turbo he was using. Better go get cracked out.

[kamotors]

I ran an H1c and its very late spooling and lazy turbo, works well if all you do is drag race and do freeway pulls. For Daily driving and auto-x I would suggest getting something quicker spooling like a gt30 or 20g.

Your car will still be stupid fast in a straight line with a holset but driveability will be lacking.

[TheTacoMan]

Bottom line holsets are way too bug for m20s.

[saturnv7890]

It's fun as hell when the boost hits though! It's not like I need boost for daily driving anyway

[ST1G]

I ran an H1c and its very late spooling and lazy turbo, works well if all you do is drag race and do freeway pulls. For Daily driving and auto-x I would suggest getting something quicker spooling like a gt30 or 20g.

Your car will still be stupid fast in a straight line with a holset but driveability will be lacking.

Meh, I don't auto-x. But maybe I would like something that spools up a little faster. What range was yours spooling?

[codrum]

I have an H1C with a 12cm housing and wish I had gone with something smaller. I started with an 18cm housing and didn't hit full boost (15psi) til mid-5k range. with the 12cm housing I hit full boost around 4500-5000, still not great. On the other hand it's been super reliable and was cheap as dirt. I've been running it for two years without burning any oil running an oil restrictor.

It's fun when it hits but you have to be on it to really get to the meat of the power band.

[ST1G]

I have an H1C with a 12cm housing and wish I had gone with something smaller. I started with an 18cm housing and didn't hit full boost (15psi) til mid-5k range. with the 12cm housing I hit full boost around 4500-5000, still not great. On the other hand it's been super reliable and was cheap as dirt. I've been running it for two years without burning any oil running an oil restrictor.

It's fun when it hits but you have to be on it to really get to the meat of the power band.

Hmmm. That's no good. I would ideally like something that hits in the 3k rangeish.

Maybe i'll skip it, a deal is only a deal if you need it.

[ak-]

M20's are stupid. It's hard to find a happy medium of power delivery that's quick as a daily and a monster when you want it to be without going into a higher liter build or corn juice/meth. They just don't flow that great.

With that said, an hx40 is too big. You need an hx35 w/ a 12cm housing for that proven m20 setup everyone does.

[Farbin Kaiber]

Just 24v then TRM tarbo.

[ak-]

What farbin said.
Even with a .140 MLS gasket lowering conpression, an m52 or s5x is anything but a dog daily driving and makes very good useable power literally anywhere in the power band with a 35r slapped on.

If I had 2 years with a second car to daily and the knowledge ahead of time, that's what I would of done slowly but surely.
So many tuning solutions out there for 24v now.