QuickTime BH runout

[AC Ventura]

I’m just dialling in my QuickTime RM 6057 BH on my new aluminium pond blocked FE 427. Everything went together pretty good (except forgot dust shield before the flywheel!) but clocking the register, I get a total indicator (concentricity) error of .022”. So it’s .011” offecentre to the crank. I’m making some offset dowels now to put this right. However I’ve read people say their’s was within the permitted .005”. Anybody else experienced an error of .022” like I have?

[HTM101]

Originally Posted by AC Ventura

I’m just dialling in my QuickTime RM 6057 BH on my new aluminium pond blocked FE 427. Everything went together pretty good (except forgot dust shield before the flywheel!) but clocking the register, I get a total indicator (concentricity) error of .022”. So it’s .011” offecentre to the crank. I’m making some offset dowels now to put this right. However I’ve read people say their’s was within the permitted .005”. Anybody else experienced an error of .022” like I have?

Almost. I have the exact same set-up. My error was around .018". I bought offset dowels and dialed it in to .001". It took a few tries. Just tightening the six 7/16" housing bolts would tend to shift it a bit, so I would re-check and adjust as needed during tightening. It dialed in rather predictably.

[RockBit]

With Pond block and the same QT bell housing, mine was .007 TIR, so .0035 out of alignment. I did have to dust out the bh holes slightly before they would slide onto the pins. I did this carefully. I also removed and replaced the bh and checked it again. Still got the same measurement, so no correction.

[eschaider]

I would encourage you guys not to use the offset dowel pin alignment procedure. It is imprecise, does not repeat with bell housing removal and replacement (w/o readjustment) and (as has been already been noted) changes as you tighten the bell housing attaching bolts.

About a year ago I did a write up on how to align the bellhousings to the blocks. It covered both the why and also the how to questions. If you are interested it's already on Club Cobra, click here => Bellhousing Alignment

The technique I describe will consistently allow you to bring the TIR to 0.001" or less.


Ed

[AC Ventura]

Thanks guys.

I've already made the pins so will try that first.
Once set I will use retainer to hold them into the block. I tap the pins M6 thru so I can insert a cap screw or bolt to rotate them. This avoids need for a screwdriver slot.
Also if you ever need to remove, you can insert a threaded rod and make a sliding hammer to extract.

[Large Arbor]

I had a same issue but was out as much as .035. I used dowels to bring it in then welded one in to the Bellhousing to make it easier if I have to remove in the future. Has worked well so far.

Phil

[AC Ventura]

Concentricity at least is all good now. Within .002” TIR.