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Timing -- Can there be too much advance?

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poulsbobill Bill K
Poulsbo, Washington, USA   USA
Well ok of course there can be. Here is my situation.

1980 spit , petronix recall, stock carb. vac retard is disconnected and all leaks addressed.

I had set the timing at 12" btdc and had tested the advance to about an additional 18" at about 2000 rpms.
What i have read is that is too soon.
So i took the dist apart and tightened up the springs ( looks like they had been stretched where the attach to the weights)
Interesting my timing lost 4" at idle. So there was too much slop at slow rpms. Now i top out at about 3300 rpms.

My problem -- playing around with the timing i am now at 16": btdc at 800- 1000 rpm. I dont hear any pinging anywhere and yet this seems way too advanced.

Back in the day i worked on my opel gt and ping was very prevalent if you went too far. I have a louder monza type exhaust but,

I should be able to hear it ping right? I mean i remember a knocking, clanking sound if i was too far advanced.

Also, anyone know what size the circlip is that is under the rotor? I lost it.

Thanks

Bill



1980 Spitfire

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Tonyfixit Avatar
Tonyfixit Tony M
Duncan, British Columbia, Canada   CAN
I am in the same situation, my idle advance is similar to yours, an I admit it DID worry me.
However the engine seems happy, if I push the timing further I WILL hear ping and I know (from testing) if I do, I am not gaining any more power.

Why I seem to get away with this, even on mid grade gas and a 9-1 compression I have no idea.

colodad Avatar
colodad Silver Member Calvin Williams
Grand Junction, Colorado, USA   USA
1979 Triumph Spitfire 1500 "Spitty"
I found a stretched spring too Bill, I replaced it not knowing why it was that way.
I have my timing at 10BTDC, have 32 at full advance, around 3500 rpm, no vac or retard just the mechanical.
Two stretchered springs, makes me wonder if it was done at the factory now.

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Born Loser Avatar
Born Loser Silver Member Matthew Taylor
Land O Lake, Florida, USA   USA
32 to 36 deg ALL IN, about 3500 RPM is about right. To check, shift into 3rd a bit early, hit a mild hill, and listen for "ping", or "dieseling". If you hear that, back off a degree or so, and try again.



Matthew
1960 Triumph TR3a
1970 Triumph Spitfire MK 3
2012 Mini Cooper SS Convertible

colodad Avatar
colodad Silver Member Calvin Williams
Grand Junction, Colorado, USA   USA
1979 Triumph Spitfire 1500 "Spitty"
In reply to # 1491325 by Born Loser 32 to 36 deg ALL IN, about 3500 RPM is about right. To check, shift into 3rd a bit early, hit a mild hill, and listen for "ping", or "dieseling". If you hear that, back off a degree or so, and try again.

Matthew, you mean the engine rattle is heard from a diesel...

Dieseling or engine run-on is a condition that can occur in spark-plug-ignited, gasoline powered internal combustion engines, whereby the engine keeps running for a short period after being turned off, due to the engine kicking back upon shutdown, drawing fuel through the carburetor, into the engine and igniting it ...

Lizzard d id
san jose, ca, USA   USA
There are some motors that are very ping resistant . Some motors were designed with low quality fuel in mind . When you run those motors with new high quality fuel its near impossible to get them to ping . With those motors you move the ignition forward until there is no improvement in power or fuel use reduction , then you set the timing back a degree or two .

Born Loser Avatar
Born Loser Silver Member Matthew Taylor
Land O Lake, Florida, USA   USA
In reply to # 1491357 by colodad
In reply to # 1491325 by Born Loser 32 to 36 deg ALL IN, about 3500 RPM is about right. To check, shift into 3rd a bit early, hit a mild hill, and listen for "ping", or "dieseling". If you hear that, back off a degree or so, and try again.

Matthew, you mean the engine rattle is heard from a diesel...

Dieseling or engine run-on is a condition that can occur in spark-plug-ignited, gasoline powered internal combustion engines, whereby the engine keeps running for a short period after being turned off, due to the engine kicking back upon shutdown, drawing fuel through the carburetor, into the engine and igniting it ...

Sure, that's a generic term. I am NOT talking about run-on after turning it off, I am talking about the sound the motor makes under heavy load, low RPM.



Matthew
1960 Triumph TR3a
1970 Triumph Spitfire MK 3
2012 Mini Cooper SS Convertible

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Lizzard d id
san jose, ca, USA   USA
In reply to # 1491375 by Born Loser I am talking about the sound the motor makes under heavy load, low RPM.
Lugging does sound like a diesel .


Brad.Cogan Avatar
Brad.Cogan Bradley Cogan
RAF Cosford, Shropshire, UK   GBR
1977 Triumph Spitfire 1500 "Wray"
1989 Toyota MR2 "Red Mister Two"
2007 Fiat Grande Punto "Pepper"
I tested mine by timing myself up a hill between two set points starting at a set speed and gear.

Then I kept adjusting it until I got the lowest time. That way you know you've got the best set up under load.



Brad Cogan

1977 Triumph Spitfire 1500 'Wray'
2007 Fiat Grande Punto Active 1.2 'Pepper'

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poulsbobill Bill K
Poulsbo, Washington, USA   USA
My mechanical advance had a 10 on it so it was supposed to be 20" at full extension. Never got more than 16". Took it apart, cleaned, oiled, etc etc. 16".

I think it was because of slop in the dizzy. Anyways i filed off about 1/32 of an inch from the stop and i now get the full 20".

I am up to 36" total advance at 4500 rpm. Gonna go back a few at the dizzy and loosen up the big spring so i get more of it sooner.

Bill



1980 Spitfire

poulsbobill Bill K
Poulsbo, Washington, USA   USA
Right now i am at 12" btdc at idle (1000 rpm)
14' at 1300 rpm
19' at 1500 rpm
25' at 2000 rpm
27' at 2500 rpm
28' at 3000 rpm
30' at 3500 rpm
32' at 4000 rpm

Seems a little steep at first.
I have read some other threads about advance and #'s are all over.
Anyone have any good website
that pertain to triumphs and advance curves? Or other info?

Thanks

Bill



1980 Spitfire

spitfire50 Avatar
spitfire50 Paul Mugford
Rochester, N.H., USA   USA
Bill,
Subtract the 12 degrees (static advance) from all entries in your table to get the actual advance. You can subtract static advance from any other table and then compare directly.
All the best,
Paul

poulsbobill Bill K
Poulsbo, Washington, USA   USA
Im kinda lookin for that table. You guys got any good links for some?

Bill



1980 Spitfire

poulsbobill Bill K
Poulsbo, Washington, USA   USA
I found this site talking about advance and changing the springs. It is for a MG though.

http://www.mg-cars.org.uk/news/news258.html

Still looking for some specific info on our cars

Bill



1980 Spitfire

Tonyfixit Avatar
Tonyfixit Tony M
Duncan, British Columbia, Canada   CAN
The info I have relates to Delco dizzies and some older Lucas dizzies as used in Heralds etc.

It probably does not help you.


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