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View Full Version : offset bellhousing dowel pins 4.6, 5.4 mod motors


ShadowBolt
08-05-2015, 04:06 PM
My Quicktime bellhousing was off .019" total (divided by two makes .0095" run-out) so I have a machine shop friend making me some .010" offset dowels. Anyone else need some? This is going to cost me about a C-Note and if you need them you can't purchase them from Jegs, Summit, or Lakewood. There are no offset dowels available for the Mod motors (4.6, and 5.4 and I assume the new 5.0). I called Accel Performance Group and they said they were thinking about making some.


JJ
AI#97
08-05-2015, 05:02 PM
My Quicktime bellhousing was off .019" total (divided by two makes .0095" run-out) so I have a machine shop friend making me some .010" offset dowels. Anyone else need some? This is going to cost me about a C-Note and if you need them you can't purchase them from Jegs, Summit, or Lakewood. There are no offset dowels available for the Mod motors (4.6, and 5.4 and I assume the new 5.0). I called Accel Performance Group and they said they were thinking about making some.


JJ

What's the acceptable limit for runout.
mach1
08-05-2015, 09:32 PM
.005" usually, thats where my alum tremec bell housing ended up too.
ShadowBolt
08-06-2015, 08:59 AM
What's the acceptable limit for runout.

Depends on the transmission. Tremec says .005". Some of the older boxes like the T10's can go as much as .010"-.015" and be okay. Tony at Astro said he doubts my .0095" is causing the issues I am having but when I sent it to Mike at Texas Motorsports Transmissions the first thing he said was I had a run-out issue. I don't know if he is right or wrong but for other reasons (like telling me to beat my driveshaft in) I will never send anything to Mike at TMT. Most set-ups with run-out issues tear up pilot bearings. Mine still looks new. There are a few videos on Youtube that show how to measure run-out. It is very easy.

I read I needed to check this when I installed the Quicktime bellhousing but I assumed since I never heard of it maybe it was BS and the run-out would be okay. I ran this set-up for four years with two junk engines without issue. Two races after installing the DSS long block all this crap started going wrong. My A5 left for Astro on Monday. We will see what Tony thinks.

JJ
AI#97
08-06-2015, 11:42 AM
.005"....good grief, I would think the bell housing would flex that much....