Timing - Again...???????

[WogsRus]

Ok So in previous posts i had a bit of a miss issues, resolved it twice, then decided to go to electronic points.

 

Now the fun part, at the old timing setting 17 deg idle, no vac, the car wouldn't run well with electronic points.

 

I have readjusted it, and it now sits at 23 deg idle no vac, and goes like a scalded cat, and i mean nasty. Unless i am totally deaf, no pinging or detonation.

 

I have checked TDC and the lot, all lines up on marks etc.

 

 

[dat2kman]

Excellent!

[WogsRus]

Well i just worried something is going to go BANG in a  big way, bit DAM its nice, so strong with the new ignition, and the adaptive dwell control, YES PELASE

[pauly_adams]

you may have a different harmonic balancer on the engine, mine was much the same on my L26, it was apparently running 20 degrees but infact it was around 8

[WogsRus]

Well that is why I did a tdc test. I tdc the piston and the balancer and the marks all lined up to zero including the dizzy, crank, piston and markers??

[600Z]

Hello WogsRus,

 

Sounds like the advance in the distributor may not be working too well. I don't know the distributor your using but in the past I had a fair bit to do with running electronic distributor on a L20B engine and given that there pretty much the same I would have thought 10deg BTDC at idle and have it fully advanced by around 3000RPM 32deg BTDC.

 

If your distributor you have has the mechanical advance within it you either weld up the limit stops or file them out so you have 11degs in the distributor which will give you 22degs at the crank. Also spot weld up your vacuum advance plate so there is no chance of it moving and changing your timing.

 

That worked very well for me and was how Murry Coote in Brisbane who was at the time heavily into Datsun engines told me how to set it up.

 

Though I don know your setup and distributor but that worked very well for me and many others at the time.

 

Just thought I would throw my 2 cents out there lol

 

Justin

[600Z]

I forgot to ask if the rotor button in the distributor has any play as in if you try and turn it back and forth if there is any slop and or if you can turn it against the advancing mechanism and springs?

[600Z]

Hello WogsRus,

 

Another thing you could consider which some people don't seam to do too much with is check your cam timing. Slightly advanced will give you better top end power while slightly retarded will give you better low down torque. This is done by checking the lift of your intake and exhaust valves on the roll of the cam.

 

If your crank is at TDC #1 then #6 will be on the roll where both valves will be open (exhaust closing, intake opening).

 

If you check with dial indicators onto your valve spring retainers and check the amount of lift each valve has (2 dials much easier and zeroed with valves closed) you can turn your crank towards TDC #1 until you get both reading the same amount of lift, remember exhaust will be closing and intake opening. Then check and see where your timing mark is on your harmonic balancer is. If it's before TDC your cam is advanced, if it's after it's retarded.

 

The stock cam sprocket has three holes for adjustment of cam timing, I made a drilling jig and drilled more holes around it so I had a total of eight which allowed for many more positions (trail and error) and found that it ran (my engines setup) best at 2degs BTDC and pulled hard to 7500rpm - 8000rpm.

 

I think there are adjustable sprockets available if you wanted to go down that path but drilling the stock one works well, its not like you change it after you have it right and it can't slip either.

 

It's fiddly to do but I found it well worth doing if you have a different cam and your after performance. 

 

Think I'm up to 4 cents of input now lol

[WogsRus]

Hello WogsRus,

 

Sounds like the advance in the distributor may not be working too well. I don't know the distributor your using but in the past I had a fair bit to do with running electronic distributor on a L20B engine and given that there pretty much the same I would have thought 10deg BTDC at idle and have it fully advanced by around 3000RPM 32deg BTDC.

 

If your distributor you have has the mechanical advance within it you either weld up the limit stops or file them out so you have 11degs in the distributor which will give you 22degs at the crank. Also spot weld up your vacuum advance plate so there is no chance of it moving and changing your timing.

 

That worked very well for me and was how Murry Coote in Brisbane who was at the time heavily into Datsun engines told me how to set it up.

 

Though I don know your setup and distributor but that worked very well for me and many others at the time.

 

Just thought I would throw my 2 cents out there lol

 

Justin

 

Well i now run 25 deg and it goes even harder. Mechanical advance appears to be working, although i will check again tonight as i don't think i tested it with vac advance off.  I have not had a chance to time in the cam, i guess over all until i do more investigation, i basically will run it as is and have a look into timing in the cam etc.

 

I don't particularly think its the dizzy as i had a dizzy in it from an L24E and it exhibited the same issues.

 

All other items like buttons slop in shaft ex are like brand new.

[600Z]

25 degs advanced seams a lot to me at idle, is your timing light ok?

[WogsRus]

You and me both, never had a car that needed this, mind you if the cam is stupid spec then perhaps it would be part of the explanation.

[600Z]

Yes that wouldn't be helping if it's a long way out of timing.

[WogsRus]

I think if it was way out cam wise, then it wouldn't run like it does, its a unbelievably tractable engine, i mean even in 5th is just pulllllsssss

[600Z]

I'm thinking that your cam timing might be out if its a common problem with two different distributors. Though could be wrong but I would be checking that probably first off as you have tried two distributors and still the same issue.