engine and drivetrain damn pinging

[Guest Anonymous]

ok all.

took out the 02 yesterday for the first time in months. thought I'd let it out a bit since I hardly run the gal.

My car has always "pinged" under hard acceleration since the restoration several years ago.

Problem though is that everything should be set.

new engine - no worn components

co2 mixture on pump is good

timing is good

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. It does it between 2k-3k rpms under heavy acceleration. It doesn't do it during normal driving conditions. It starts up fine in both cold and warm and has a perfect idle.

what am I missing here?! it's so annoying to have a car that you've gone over everything with do something like this.

[Guest Anonymous]

(nt)

[Guest Anonymous]

I have a 2 liter motor that did that with 9.0 pistons, 275 degree cam - lash caps -A very mild tune I have a suspicion that it may be the cam.

Slavs

[Guest Anonymous]

octane: 87 and/or 89

cam: standard tii cam (262?)

compression: 9:3.1

[Guest Anonymous]

(nt)

[Guest Anonymous]

Are you in CA where 91 is premium or at elevation where 87 is all that's available? 87/89 seems a bit low for a tii near sea level.

My car pings like mad on 91 octane, runs fine on 93.

I have 10:1 pistons and a 300degree cam. PO (and engine builder) calculated 9.8:1 CR but was using a +.3 head gasket at the time.

[Guest Anonymous]

If you run low RPM and are trying to boot it, then chances are it is going to ping. Try by backing ignition a bit, but run higher RPM.

[Guest Anonymous]

Try a couple tanks of premium and see if that helps.

Matthew Cervi

'73 tii

[Guest Anonymous]

(nt)

[Guest Anonymous]

it does it between 2k-3k rpms under heavy acceleration. I'm not "under-geared" at the time either.

My tank was dropped and cleaned when I did the restore 3 years ago and have tried various octane levels for multiple gas tank fills.

It does not go away with higher octane.

See my frustration? This will be the year I nip this in the bud!

Great input so far. Much appreciated. Thanks.

[Guest Anonymous]

I would check the valve timing. I'm just thinking if a valve or two are too tight then maybe they could tap the piston. No? I'm just guessing. Maybe the timing was never set right to begin with.

[Guest Anonymous]

(nt)

[Guest Anonymous]

(nt)

[Guest Anonymous]

(nt)

[Guest Anonymous]

(nt)