Tii distributor advance

[bnam]

Today I tried setting the advance per the spec (25deg at 2700 rpm) -- previously I had set it using the "Secret sauce" method of ~6-7deg at idle.

When I set it to the 25@2700 spec, at idles I am retarded a few degrees ATDC. Is this an indication of weak springs? This is reportedly a new distributor (and looks it).

Where can I get better/correct springs for this distributor? It's a new/remanufactured Tii unit.

Thx!

B

[jgerock]

I don't think you can get new springs for a Bosch distributor. Even if you found some, it would be tricky to get the correct ones for your distributor, especially if it has been recurved. You can buy generic springs from places like Jeg's, but those are meant for American car distributors. There was an older magazine article about the owner of a 72tii that installed springs from a Corvette and it made his car run better. No mention of the exact springs or year that he used. This article appears in the Brooklands Gold Portfolio BMW 2002 book.

If you distributor is the correct one for a tii, then the Torres/Kreeger timing recommendation is what I would set it at. I used it before I had my original distributor rebuilt by Advanced Distributors. For a little over $ 100.00, it is a very worthwhile investment.

Jim

[aa/fd]

No it means that the device for limiting the total advance is allowing too much travel of the advance mechanism. Weak springs will just allow it to advance quicker. My Tii runs well with 32 @ 2700, only rattling a little when it is hot and dry out. That is a rare occurrence in Seattle.

In the Bosch Distributor there are two tabs that limit the fly-weights travel.

If you remove the point plate and expose the advance you will see the weights, springs and the two tabs pointing up at you. To adjust either bend them to center for less travel or braze them up a bit, or even a piece of rubber hose over them. I don't recall how much clearance there is between them and the case so that could be an issue.

[c.d.iesel]

B - are you installing this "tii" distributor in a 2002 carburetor or 2002Tii motor ?

[bnam]

CD, this is on my 74Tii.

Jim, I'll check out Advance Distributors. Will go back to the Torres/Kreeger recipe for now.

Will also check out the tip in the advance limiter.

Thanks!

Byas

[TobyB]

Another thing to try- set it at about 35 at over 4500.

Then see what it idles at.

t

[conkitchen]

Can I thread jump a little to ask about the turbo's dist advance curve?

C.D. any specs you hight have in that archive of yours?

thanks in advance, ;-) pun intended.

[jgerry2002]

When you check the timing with a light does the ball appear to bounce around?

If so its weak springs, maybe sticky weights.

I can recommend Jeff@advanced distributors, I've installed a few of them.

Timing light is rock solid, ZERO bounce and its super easy to set the timing at idle. The way he curves 'em its 10-14 degree at idle. About 12 degree seems to be a sweet spot. Motors run like perfect sewing machines at idle. No bouncing or shaking. No run on or anything else weird when you shut 'em off.

Tii its VERY critical to get the timing 100%. We spend so much time debating the perfect measurement of the linkage and yet we ignore timing!

[bnam]

I use the pulley in front -- no the mark is fairly steady. I don't use the ball - (a) cause car came with lightened flywheel and not sure if it has the ball, and ( I tried to get the light over the ball, but the snorkle of the intake gets in the way. And, removing that inner snorkle is a pain -- have to take the airbox out etc. And even if I removed that, the return fuel hose is in the way, so I'd have to move that as well -- so gave up.

When it was at 3-4deg ATDC @ idle (25@2700), car still ran well but starting was a bit harder and there was a bit of a run on when I turned it off.

I've now set it to about 3deg BTDC -- which should be about 31@2700. Car starts and idles well and starts and turns off easily. Will drive at this setting for a while.

I have a 292 cam on the car. I'll first install a WB02 and tune before deciding to recurve the distributor.

Byas

When you check the timing with a light does the ball appear to bounce around?

If so its weak springs, maybe sticky weights.

I can recommend Jeff@advanced distributors, I've installed a few of them.

Timing light is rock solid, ZERO bounce and its super easy to set the timing at idle. The way he curves 'em its 10-14 degree at idle. About 12 degree seems to be a sweet spot. Motors run like perfect sewing machines at idle. No bouncing or shaking. No run on or anything else weird when you shut 'em off.

Tii its VERY critical to get the timing 100%. We spend so much time debating the perfect measurement of the linkage and yet we ignore timing!