Turbo exhaust housing.

[20gst]

I got a HRC super 20g and Im going to change the 10cm exhaust housing for an 8cm and go with an external type set up. My turbo has a Compressor Inducer/Major Diameter of 2.075/2.675
Turbine Exducer/Major Diameter of 1.930/2.200
Will my exhaust wheel work with an 8cm ok or what ? This turbo is a Mitsu., and I dont know whare to find any housings for em, do any of you know whare I can find it at or buy one.
The reason Im doing this is because I think my internal flapper is broken and Im loosing boost here. I tested everything else and this is my only answer. I will know for sure this weekend when I pull it off to see. Thanks............

 

[L2RTSiAWD]

Did you just get a good deal on the turbo?

Why change the housing? It will proably negatibley affect the turbo's performance.

 

[20gst]

Na Ive had this turbo new for only 5 months now and Ive lost boost. The only thing left for me to check is the flapper door to really make sure. Believe me, Ive checked it all and its good.
I wanted to do this swap with the exhaust side due to cash flow, I figured this would be the cheapest way to solve the problem. I dont have time to down my car while the flapper is being fixed elsewhare ,I can do it myself and weld a flange for a wastegate easy in my garage and be up and running in a days work .
So why would this 8cm housing hurt me if I did this ?

 

[Ben K]

You have a TD05H turbine wheel so any standard 7cm or 8cm turbine housing for a DSM will work just fine. We have a few 7cm around here that we'd be willing to sell really cheap.

Ben
AGP Turbochargers, INC

 

[talon91tsi]

for one you would be reducing exhaust flow. you have a 10cm, going to downsize to an 8cm. take it apart see exactly the problem for suse and go from there. probably just have huge cracks in the housing. mine did and i had a similar problem. had it precision welded and ported a little bit and in has been good since.

 

[20gst]

Thanks, how much and going down 10cm to a 7cm is quite a jump, what if any affects will this play on the overall powerband, spool, and rpms.
Will everything still be the same, just different stages of lag due to flow or what. ?

 

[ChicagoGSX]

I think the HRC Super Turbos use a different wastegate actuator so you may have to get a wastegate actuator from a regular 20g. You might also want to look at just switching to an external wastegate.

 

[20gst]

Originally posted by ChicagoGSX
I think the HRC Super Turbos use a different wastegate actuator so you may have to get a wastegate actuator from a regular 20g. You might also want to look at just switching to an external wastegate.

 

[20gst]

Yeah if what I find is true inside the turbo I will be going to an external for sure !!!!!!!! I just need to see what effects a 7-8cm housing is going to do to my turbo first.
Maybe Ill just keep my 10cm housing and weld it closed real good and just drill and weld a flange on #1 for an external set up and save money that way and hopefully fix the problem.

 

[candela]

Uh.... no #### shelrock he said he wantsto get an external. Anyhow the HRC turbo's are still mitsu which means its the same as any other 20g except you have that dumb ass 10cm housing. Just about all 20g's have 7cm housing on them anyway, td05h or td06 dont matter. Im sure youll pick up some spool and maybe even a little more midrange. Ive only been in a super16g car not a 20g, but I have been in a regular 20g'ed car... HRC's housings stink I think getting the 7cm, porting the nuts out of it and putting an external on the manny is a great idea

 

[20gst]

Yeah I got some new gaskets, so this weekend Ill spend time pulling this thing and examine everything. Ill look for a 7-8cm standard/external type. I guess Ill be spending my income tax check for a new wastegate huh... After doing this mod I will post my remarks on how this works out.