I'm working on installing a 71HTA and need some advice.

The factory CHRA slid out and goes back in without a problem but the 71HTA won't slide into the turbine housing. Looking at the two side by side it appears that the metal seal below the factory turbine wheel is tapered while the 71HTA is 90 degrees. It looks like that is what is keeping it from sliding in. I'm not using any force since the factory turbo doesn't need any force to put together and I don't want to damage the new turbo.

Does anyone have a 71HTA on hand that can compare it to my picture below for confirmation?

Thanks in advance for any advice!

 

Mine was done last year and didn't have any problems. Post a closer photo of the new turbo and your exhaust housing lip. Something is off and maybe we can see it.

 

Look at your exhaust housing and clean out the lip. It is probably corroded and the corrosion doesn't match up to the new turbo lip since this is new. And make sure the tiny dowl pin on new turbo lines up with hole in your exhaust housing.

 

Thanks for the reply!

I got some more pictures of the housing and turbo below.

 

I cleaned out those areas to ensure there was no corrosion. It won't even seat far enough to reach the dowel.

Here's how far it will go in and I found some carbon on on the corner of the seal. It looks like the metal seal is too big for the turbo.

 

is that a 9.8 or 10.5 turbine housing?

 

Good idea, I'll research the appearance of both to confirm it's the 10.5.

It should be the factory turbine housing for the Evo IX, it only had 22k when I got it and was basically stock. That said, I remember the ****ty previous owner mods from my DSM days...

 

easy way to tell, the 10.5 has a single hole in the wastegate flapper and the 9.8 has 2

 

Found a thread with the different turbine housings compared here: https://www.evolutionm.net/forums/ev...m-turbine.html

It looks like it's a 10.5. Phew.

 

cool, at least thats one problem it isn't.

 

Can you look through exhaust side and slowly assemble the 2 pieces? Something isn't fitting deeper inside.

 

Do you have a way to measure the diameters? Are these two diameters the same?

 

Good idea. I just measured the circumference of the metal seal and it's 20cm for the factory turbo and 21cm on the 71HTA. I also measured the distance from the edge of the turbine blade to the lip of the seal.

Unfortunately I can't get a good picture from the other side since I hadn't planned on removing the O2 sensor housing.

Here are pictures of the blade measurements.

 

I doubt there's 1 cm diameter difference between the two. From your wheel measurement, it looks like 71HTA radius is 2 or 3 mm, which would add up to about 0.5cm diameter. Either way, this could be why your hotside isn't fitting. Measure the inner diameter in your hotside and it's probably smaller than the 21 cm you measured. Contact FP to find out if they sent you the wrong piece (is this called the collar?).

 

If you dont have any vernier calipers to measure it correct, get a piece of string and measure the circumference. Then you can compare the sizings.