I bought a k31 thinking they only made one size, boy was I wrong! The one I have has a 66 mm wheel on the cold side and I was wondering if they can have the wheel and housing exchanged for bigger wheels and housing like other turbos? I would like to use this as a second turbo under a 35-40 on my wifes truck. It looks like it would work good having a wastegated exhaust housing to tune with. Any info would be appreciated.

 

I have a k31 primary in my truck feeding a Dodgezilla. The compressor wheel inducer measures around 70mm. It makes a very nice setup, but is a bit small if you are looking to go over 500hp. Going to a larger secondary charger will help the top end a bit, but a bit more lag is inevitable.

Ron

 

I was hoping this turbo was like the one you use when I bought it. A 66 wheel on the primary is probably too small to do much good. I was hoping someone would know if larger wheels and housing could be substituted on this frame I have. It might be easier to just sell it and buy a 3b as they are a proven setup.

 

I think the best application for the K31 would be for a 400-475hp towing twins setup. The wastegate allows you to easily control total boost. You might want to call City Diesel and see about the wheel change. The titanium comp wheel and new comp housing will probably cost more than a new 3b though.

 

A 66 wheel on the bottom turbo is way to small isn't it? I was going to setup either a hx35 or maybe even a hy35 I have laying around for a real quick spooling setup with a external wastegate. Do you think the k31 would be big enough for the hy to compound decent. I would be running the drag comp and switch from the 115 injectors to a set of 150 horse injectors. That combo ought to get into the mid 400 hp range I would think. What kind of boost is the k31 able to run cool at and do they come in pretty quick?

 

What housing on the K31?? 1.10A/R??

We ran a 64mm/1.10 housing S400 under a HX35/40 (58mm/12cm) and it cooled a DRAG COMP, and 155hp Jammers (really 108hp ). Worked great, boost was 60psi, and towed AWESOME with a built DTT.

I would think it would be wicked with an HY on top, especially with an external gat on the HY. The wastegate on the K31 will help keep overall boost down, and should help out drive pressures a bunch when you push them hard. I would say limit the K31 to somewhere around 35psi...but a 66mm wheel may be able to handle a higher P/R than the 75mm wheels. Might be able to run 38-40psi on the primary if need be. I'd start at 30, and see what EGT's are, then bring boost on the primary up a few psi at a time untill it doesn't make a difference, or makes temps higher (overheating the air)

Good luck,
Chris

 

I will try to get the numbers off of the housing if I can find them this weekend. I would really like the have a super fast spooling setup, the 35 over a 3e I have on the 97 ain't bad at all. When it hits 10 lbs it is all over.Thanks,Gary

 

My K31 has a 1.28 wastegated housing with a compressor inducer that measures around 70mm. I have it set to make 30psi with 60psi at the intake manifold. The boost gauge on the primary lifts off the peg at 7psi of intake manifold pressure. With the Dodgezilla/14 on top it is a super tow or daily driver setup. I'm not heavily fueled(Mach 1.2 injectors), around 475 hp. I run around 575 to 625 egt on the highway at 60-70mph. It pulls better on the bottom than my DZ/3b-23 combo did. It spools quicker also. My DZ/3b setup was at 503hp and would not spin the tires spooling up in 3rd or 4th gear. This setup will do it easily. I bought a B2 and a HTT super stock 62 a while back for a try at more hp. I am having a hard time getting started on the piping because this setup works so well. Fuel mileage is up also.

Ron

 

I just looked at the k31 while I was swapping mirrors on the wifes truck and couldn't find any numbers on it I could identify with. Can you guide a like me to the right numbers? I told my wife I was going to build her a set for her 02 and she said she didn't want them if it makes her truck as quite as mine so it looks like the high mile 01 is the canidate for them. Thanks,Gary

 

They are on the inside of the exhaust inlet!! should be stamped there on the side wall of the housing, on the inside!

Chris

 

The outside row of number are 5331 101 9064. The inside row are almost all letters ggg-simo 20.9 The intake snail has a row of numbers on it 5331 101 3064. Do these numbers mean anything?

 

Not really...here is a pic with where you need to look!



Not a K31, but it is/was a turbo!!
Chris

BTW, if it's wastegated, it doesn't really matter on the housing size...unless it's bigger than 1.28!! A B2 is 1.32, and spools pretty well, but it's got a 75mm inducer!!

A 66mm will work for 500hp and under...but over that, I'd find someone to make it into a 70mm at least! If you wanna go over 600, go with a 75mm!

 

MAN, was the turbo part of a nuclear explosion or what! I have never seen one hurt that bad. I went and looked, it had the 20.9 number on the inside of the ex. housing. I'm really looking for a smaller setup than the hx35 3e setup I have on the other truck. When I had the 3e and the k31 side by side the k31 was smaller on the exhaust housing and the intake housing but not alot. I think I'm going to try it with the hy35 I have and shoot for a max of under 500. I've got a big external wastegate for the 35 so it ought to be able to breath aroung the little turbo alright.