engine and drivetrain damn pinging

[Guest Anonymous]

I would check the distributor for springs on the advance mechanism and also how much total advance your distributor puts out. All the advance should be in(Talking Tii here) by about 3500 rpm. Max centrifuge advance is only 16 degrees so to get 32degrees total advance a static setting of 16 degrees befor tdc seems appropriate and a 2400rpm advance of 25 degrees btdc.

Seems you have most everything else under control a new tii distributor would be a good reward for getting this far. Have fun

[Guest Anonymous]

-barring vacummeleaks (which would presumably affect the whole range) with the stock cam/ correct pump for that head and compression ratio (slight difference in curves as you know.)

I would (did) check the actual A/F ratio at running speed with a wideband meter- preferably one that can log. And have the advance curve checked (I did it myself with an adjustable timing light.)

My guess is (assuming the advancee curve is spot on- should be 0deg at idle) that you are running a little lean across the whole range. The mixture should richen up a little at high RPM WOT for power and be a a little leaner at lower RPM WOT. After checking with the A/F meter you could decide if the mix is off across the board or just at on spot. If across the board i would (did) make adjustments to the entire range with the screw on top of the pump (previously refered to as the "don't touch screw."

This is only a good solution if you are super sure that the ignintion and all throttle setting/ compnmonets are tip top.

Currently my A/F reads in the high 13's and drops down to the low 13's at wot as the engine speed increaces. I had pinging at high rpms and backed off the timing 1 degree and it stopped.

I got my wideband from innovate motorsports- you could also find a shop that has one or get on a dyno (4 gas analyzer would give you the best info but I've never used one so....)

[Guest Anonymous]

My '71 pinged like mad and the culprit was the distributor. They wear out over time and cause the timing to go off. I would suggest replacing yours if you did not during your restoration. Otherwise I'd say your running too low octane petrol. You should always run premium in these cars.

Brandon

'72 Tii (track car)

'73 Tii (restored w/working Behr A/C and Sunroof)

[Guest Anonymous]

""new engine - no worn components

co2 mixture on pump is good

timing is = = = = = = = = = = = = = == = = == NOT GOOD - how are you setting IT ?

plugs are good

no fluid leaking into brake booster

no intake issues

no carbon/buildup (remember, new engine)

warm up regulator is good

cold start valve is good

I see no reason why it pings but it does. ""

[Guest Anonymous]

several times. same or worse results.

the ball lines up perfectly on the timing marks so the timing should be set.

I'm going to try several tank fulls of 93 with possible octane booster if necessary. I've tried 91 and 93 in the past but probably not consistently enough.