Ok guys, some of you may know already but I've gone ahead and put a 94 SC and TB on my car. Really neat stuff but I'll stick to the details. The camera I used was a junk disposable, my digi was out on loan. Numbers first, pics at the bottom:

1993 Throttle Body:
Intake Outside Diameter - 3.37"
Intake Inside Diameter - 3.02"
Output Inside Diameter - 2.26
Maf housing - 0.7" tapers to 0.61"

1994 Throttle Body:
Intake Outside Diameter - 3.65" (+.28")
Intake Inside Diameter - 3.35" (+.33")
Output Inside Diameter - 2.88" (+.62")

1993 Supercharger:
Intake Inside Diameter - 2.34"
Bypass Valve Diameter - 1.52"

Main Output:
1.71" across
3.99" long

Small noise reduction holes:
0.65" across
0.91" long

Vacuum Connector - 0.65"
EGR - 0.52"

1994 Supercharger:
Intake Inside Diameter - 2.81" (+.47")
Bypass Valve - 1.5" (-0.02" operator error?)

Main Output:
1.67" across (-0.04")
3.87" long (-0.12")

Smaller noise reduction holes:
0.52" across (-0.13")
0.77" long (-0.14")

Vacuum Connector: 0.65"
EGR - 0.65" (+0.13")

I've also measured all of the vacuum holes on the bottom and all of the mounting areas. The '94 has a much thicker case, over 0.3" thicker in some areas. The '94 throttle body MAF housing is also different. While the '93 tapers the '94 is a straight 0.71". It also has a 'ramp' of sorts to angle the air into the filament.

There was only two issues I found with this swap. One was the difference in the EGR size. I fixed it with some sealant and a new bolt which seems to have made it work. The second issue is because the '94 housing is thicker the fuel rail doesn't sit as far down so the injectors don't seat as deep. This does not seem to have caused much of a problem as of yet, but I'm still tinkering with it.

Oh for for those of you curious, while I didn't install it and test it I did bolt the '94 throttle body to the '93 supercharger and it fits perfectly. Kind of strange opening the valve and seeing half an inch of the SC intake hang over...but as an upgrade? Hmmm...



Now for some pics (guess which is which):









Hope this has been helpful.

Didnt jeff also try this? Would this only give you a gain if the blower you currently have on your 93 is restricting the flow (which if i remember right was his theory behind the swap) or would it benefit anybody?

Yeah he did, I didn't get much of the details out of him though. I look at it as an upgrade no matter how you slice it.

The '94 is not only much larger but also has a higher volumetric efficiency. This means you can spin the supercharger slower and still get the same output. That on its own has multiple benefits. Think of it like this, it'* possible to spin an m62 fast enough to produce the same flow as an M90 because it'* a positive displacement pump. But it will always be better to spin the M90 at 14,000rpm than spin an M62 at 19000rpm just to match it. Same thing with the 93 to 94 only on a smaller scale.

An illustration of this point is already known. The '93 and '94 have the same crank pulley so they're both using the same ratio to spin the supercharger. They both get about the same amount of boost yet the '94 is 20 hp more than the '93. The '94 achieves this while still spinning 11% slower than the '93.

I haven't seen much of this swap so I'm totally open to opinions and thoughts.

Pretty interesting stuff....

It'* pretty clear when they are side by side the size differences...

From what he was telling me back when i wanted to do this ( he no longer says anything to me, i have no idea why) he noticed a significant gain from it, i think somewhere near a 20 hp gain. He said to do this before i go inside the motor with things such as a cam etc. The only reason that i didnt try what your doing is because another member believed that i woudlnt see any worthwhile gain from it. Either way its nice to see someone kinda taking the lead on it.

That TB difference is HUGE. Same for the blower inlet.

.. and its noticable. The 94-95'* i've driven seem way quicker than 92'- 93'*.

I did the swap the same time Jeff did. Still running it. You'll notice one SC to LIM bolt is longer than the rest on the 93, while 94 are all the same length. Also the coolant paths don't exactly match up between TB and SC.

Getting the fuel curve right has been the trickiest thing for me. It always seems to blow a little smoke when I get on it. Oh well, the scan tool is coming soon so I can nail it down. I can't really vouch for more power. Cause when I did the swap at first, I didn't know about recalibrating the MAF signal and it ran really lean. So I put my 92 TB and MAF sensor back on it till I got the AFC. The power difference then felt quite significant, but that may have had something to do with high speed air entering an abruptly larger opening and getting turbulent going into the rotors, then going to a smooth transition with a larger TB.

x2

I'll be able to test the diff. first hand in the near future. Also Jay, the 2" pulley came in (nice) and I can honestly say I'm scared - it is really tiny!