3X2

Short story long, I installed a 67 435 intake manifold. Question is: what direction should the vacuum advance face? The 69 distributor box doesn't clear the ignition coil. I went and got a 67 box and brackets, but it won't clear the vacuum advance can where mine is currently facing. I looked at some pictures of 67 435's and the cans are all facing 4 o'clock when looking towards the engine from the right side fender. Currently mine faces 6 o'clock. I repositioned it like that and there's a serious bend in the tach drive cable. Options as I see them (there may be more): 1- keep distributor as is and modify 69 box as needed. 2- use the 67 box and reposition the distributor. 3- same as #2 but get a 90* adapter for the cable. 4- I could modify the 67 box to clear the can, but due to the shape of the right side box mounting bracket, there is not much space to rotate the distributor counter clockwise. AIM says distributor cap attaching clips should be 15* rearward in relation to the rear face of the block, mine is more like 45*. Personally, I'd like to keep the 69 box.

Net dumb question: to correctly reposition the distributor, I raise it from the manifold, reposition the body, drop in in while maintaining the direction the rotor is facing, then install the plug wires in the correct position for the new location of #1. It's been many years since I played with a car with a distributor............and carbs.

toobroketoretire

You always view the engine from the driver's seat; not from the right fender. When viewed from the driver's seat the vacuum advance should be pointing at a 45 degree angle to the right side. That'll make the tachometer cable form a reverse "S" shape.

3X2

So, this is the correct position even if the tach cable has what I would think, a severe bends? Picture is of a 69 435 car I saw.

toobroketoretire

Yes, that is correct. Your tachometer cable will end up with a reverse "S" bend as the distributor's tach drive will be pointing at a 45 degree angle to the rear. It may look "severe" to you but its not as the tach cable (actually a spring) easily spins in that tight bend.

Your #1 spark plug wire should be in the 11 o'clock position in the distributor cap. Is it?

CanadaGrant

I have my 69 427/390 distributor set one cylinder over clockwise. The inlet for the vacuum can is between the two vertical passenger side arms of the ignition shielding box and does not hinder any base timing you want. This gives the tach cable a straighter shot at the distributor. I think there was even a GM bulletin out in 69 or 70 about changing the distributor to this position. Your description on how to clock the distributor is correct except you don't have to move the plug wires. You are turning BOTH the distributor and the shaft one gear over so plug wires remain the same as the rotor and cap are still in the same relative position. If you were just turning the distributor without changing the position of the shaft you would then have to move the plug wires.

69FASTFUN

This is what my 69 looked like when I owned it

pltmgr

The PO had no vacuum advance on my 3x2 setup. When I installed one it was in the 7 oclock position. Indexed the distributor as you described but I then moved the spark plug wires to their "factory location". Just keeps things simpler for me and the next owner.

I was under the impression that the 67 3x2 setup would clear the stock hood of a C3.

toobroketoretire

By rotating the distributor gear 180 degrees in it's shaft you can move the distributor housing 14 degrees degrees plus or minus to "fine tune" the position of the vacuum advance. The distributor gear has 13 teeth which means each tooth is equal to 27 degrees. By rotating the gear 180 degrees you advance/retard the housing half that 27 degree amount.

3X2

Not a stock SB or BB hood, but does fit under a L88 hood.

MelWff

scroll down to the alternate C3 distributor instructions
http://www.corvette-restoration.com/...stallation.pdf

toobroketoretire

Regarding the speedometer and tachometer cables I never use the little "crimping" tool that comes with the new cable. I epoxy the squared end onto the cable which produces a much better outcome as the squared end doesn't get distorted.

3X2

That bulletin for relocating the distributor was issued in December 1967 for 68 327 Corvettes. it states that all other v8 engines stay wired in the conventional manner. Not sure why only 68 327's, since the reason given is "to gain needed clearance between the tachometer drive cable and fire wall". I've had my 427/435 clocked per the bulletin for probably 30 years. FWIW, clocked this way, the 67 distributor box won't fit. I've gone back to using the 69 box and waiting for a msd coil to arrive. It should fit inside the 69 box. I just need to cut a piece of aluminum to mount the coil to.