When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I am in the process of fitting a set of RCM headers and a MD321t turbo to my import bug sti. After fitting the headers we found the turbo wouldn't fit and iv been told to remove a lug from the bell housing.
Before doing this we tried to fit the standard turbo back onto the new headers only to find it wont even get close to fitting.
Seen this numerous times when I looked at an MD321. Saw a load of people that had to chop part of the gearbox away to get it to fit. Its not the headers, its the turbo
As above I had exactly the same thing on my old MY03 STi. MD321T required the lug to be removed or at least modified for the turbo to fit. That was with Perrin Headers
But he had a problem with the original turbo also. Maybe they are bent. I had an issue with OEM twin scroll headers which gave me a gap between header and up-pipe. Bought another set and the problem was gone.
How much do you need the grind a six speed gearbox to make a MD321T+ fit? If I had known about these issues I would probably bought another turbo or gone rotated. To me it seems crazy to grind the engine block and gearbox because of a turbo.
A friend of mine has a blob sti with an md321t on. We fitted williams headers that have a slip jointed up pipe. To get the best fit we bolted the headers on 1st then put the standard support brackets on the engine/gearbox. We then offered up the up pipe by bolting it loosely to the mounting brackets and loosely at the headers end. We then tightened the flange/headers end 1st, then secured it on the brackets at the turbo end.
We had to grind away about half the top left bolt bulge, to the point where the bolt was showing, about 3 inches of it. I did have a pic but was on my old phone.
Have seen loads of threads about the MD turbo, needing a piece ground down.. on the headers, up pipe turbo, downpipe, fit everything loosely and tighten everything up bit by bit together
Due to the physical size of the uprated turbo, it is normal practice to 'clearance' the bellhousing of the right hand crankcase in order to fit the turbo without interference.
Top left of the picture shows where I have removed half the bolt hole to fit a MDX321V - and you can still fit the bellhousing bolt and tighten it.
Yeah I had to remove about as much so that the thread was exposed but only on the front 1/3 of the thread's length. I think I may need to shorten the bolt though for it not to touch the compressor housing. I have the "twin scroll" version of a MD321T+ though so it may sit a bit differently compared to single scroll.
But do you need to remove that much on the gearbox casing also? I'm waiting for my six speed to arrive so haven't had a chance to look into it yet but it seems it will the touch the exhaust housing of the turbo.
Last edited by Turbovin; Jul 30, 2017 at 09:01 PM.