EFI Bung in head update

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Nice work!

I could not see, but I assume the timing wheel has a missing tooth reference? The other option is additional cam or distributor sensor, for sequential EFI, and COP ignition.
 
36-1 wheel, i need to knock down the 6th tooth ahead of the sensor @TDC on a 6 install and i have to determine which one it is after mounting and timing. Looks like itll be the one close to TDC as i can mount the sensor so it will be that tooth. Would make it all ghe easier to find TDC if its smack dab in the middle of the void.
 
Your plan sounds like a solid triangular support for the shock tower. I'll try to get a photo of how my C-body does it. The inner fender is removable and curved. There is a fibrous flat material that seals around the UCA. I recall that B-bodies are similar.

Your teeth are plenty deep for pickup. If the sensor is only 200 mils away from the surface, I think it doesn't pick up, so probably that would be deep enough, though I have seen photos of Ford wheels that have teeth as deep as yours.

Mounting the pickup on a slant looks challenging, since there are few bolts to come off of for a rigid mount. Before you cut down a tooth, read up on the Megasquirt site. If you plan to use a Ford EDIS module for timing control, I recall that the missing tooth should be something non-intuitive like 50 deg before TDC. That will give ~10 deg BTDC spark for the limp-home mode. I set mine up on my 65 Dart SB, but it has been a few years now (search my posts), and I haven't installed the EDIS stuff yet, so don't know if I got it right.
 
Bill is correct, the missing tooth is much ahead of TDC, there is much to, things like dwell for spark. It is often placed where the gap it is not encountered in timing measurements. The first rise after the missing tooth is the sync.

As a side note.
The way the gap is sensed if fairly simple. Teeth are measured using a timer registers, if the span between teeth is greater than 2x, it is the missing tooth, the actual time is 3x. It is easy to do with micro, only a subtraction, bit shift and compare, very fast. The subtraction needs to be done anyway, because it is used to measure the interval that is later subdivided for timing resolution . Since a normal tooth is 1x, the 2x test works and rejects any false triggers, because the engine cannot change speed fast enough to make it fail.
 
pishta,
As promised, photos of how the front shock tower is supported in my 65 C-body. It has a cut-out in the inner fender around the LCA, similar to what your car now has. I recall that B-bodies are similar. In mine, the shock mounts inside a tube welded to the frame rail w/ gussets. The tube doubles as a dust shield, so the shock is smaller, w/ just a rod out the top. The opening is covered by a material similar to very thick roofing felt. Mine fell apart on the driver's side. It is easy to get at the UCA cam bolts for alignment. The inner fender bolts in.
 

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Bill is correct, the missing tooth is much ahead of TDC, there is much to, things like dwell for spark. It is often placed where the gap it is not encountered in timing measurements. The first rise after the missing tooth is the sync.

As a side note.
The way the gap is sensed if fairly simple. Teeth are measured using a timer registers, if the span between teeth is greater than 2x, it is the missing tooth, the actual time is 3x. It is easy to do with micro, only a subtraction, bit shift and compare, very fast. The subtraction needs to be done anyway, because it is used to measure the interval that is later subdivided for timing resolution . Since a normal tooth is 1x, the 2x test works and rejects any false triggers, because the engine cannot change speed fast enough to make it fail.

...and another reason why I didnt become an engineer! So...the missing tooth is 5 teeth clockwise of the VR sensor right about where the TDC timing tab is. Conversely, the VR sensor will be mounted 5 teeth to the left of the missing tooth regardless of where that may lie on the timing chain cover. Bring in the tack welder!
 
pishta,
As promised, photos of how the front shock tower is supported in my 65 C-body. It has a cut-out in the inner fender around the LCA, similar to what your car now has. I recall that B-bodies are similar. In mine, the shock mounts inside a tube welded to the frame rail w/ gussets. The tube doubles as a dust shield, so the shock is smaller, w/ just a rod out the top. The opening is covered by a material similar to very thick roofing felt. Mine fell apart on the driver's side. It is easy to get at the UCA cam bolts for alignment. The inner fender bolts in.

Bill, I got bumpkis for inner fenderwells! I need the J bars in there to tie in the shock struts and to somewhat support the front end. After the J's are installed, Ill form some thin AL skin to emulate what I cut out years ago and pop rivet it into place.
 

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