Which model holset hx35 turbo should I get for my 2001 automatic 4x4? The hy has been great, but now that it has 230,000 miles on it, I keep feeling the need to replace the turbo before it decides to come apart.

 

Ck the end play of it. Up/down & side to side there should be very minimal play. The bearings are free floating. Any play in the shaft front to back is more reason for concern. If going to the trouble of changing it out I'd look into a turbo from an 04-06...I think they're the hec351. I'm sure someone will chime in if that # isn't completely correct.

 

There seems to be so many differrent holset hx35 turbo models, I wanna make sure I get the right one

 

Just pick up a used one from someone who's upgrading to something bigger. Anything more than that you won't really see any benefit given your current mods.

 

Or you could get a rebuild kit for your current turbo. I got one off ebay for about $35 when I put together my hybrid 35/40 and as long as you are gentle and careful, it's not too hard.

The hy will have quicker spool-up due to smaller housing and hits choke point with a j-hook somewhere around 30psi. Might be a better turbo for mild fueling anyway.

 

I am told that a hy spins up faster (smaller exhaust section). You will not be happy going from hy to hx with an automatic.

 

Hx35 is a direct replacement for the hy35. I've been really happy with mine...max "effective" boost is up to about 35psi.

 

The Holset part number for 99-02 is 3592766. You can also use 3539343 from a 98.5. The 3537815 used on 94 to 98 can also be used with some tweeking. I replaced the HY with the HX on my 01 and notice no difference.

 

You can put a $6.00 turnbuckle on your hy and get 35# boost also, with more boost at lower rpms than with hx

 

This was a resurrected thread from four months ago, so the OP may have already figured out what he's going to do.

Oldbeek, the HY does spin up quicker due to the 9cm2 exhaust housing, but it falls down earlier to the restrictiveness of that same housing. The difference between the HX-35 and HY-35 isn't much, and with fueling mods normally the better top-end airflow of the HX outweighs the small difference in how quick it spools up.

On an automatic it doesn't really make much difference--the turbo spools up once and then boost is mostly maintained as the transmission shifts through the gears under load.

On a manual it can make a difference because boost really falls off during gear shifts (unless you're trying to be Mario Andretti with the speed shifting maybe).

 

Thought I'd add this for anyone reading this too. I have read here that switching from the HY to the HX will drop your EGT some. Not to important for driving around unloaded, but helps when towing.

 

Ok I know very little about my turbo...or how it works..i.e the waste gate, what is a J-Hook, when should the waste gate be open and closed.