RobBrown
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| posted on 24/7/06 at 07:23 PM |
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Pinto Timing - Forgive my ignorance
After spending a whole week trying to tune my 2ltr Pinto, with DHLA40's and a 300deg Cam. I eventually came to the conclusion that I dont quite
understand what I am doing.
Timing facts
1. Piston goes up and down
2. Cam does round and round
3. Dizzy induces spark at correct moment
When we talk about static advance needing to be between 16 and 18 degrees, is this for all 3 components?
Before I start twisting the dizzy to get the right spark point, how do I know that 1 and 2 are timed correctly? i.e. When the Cam is at TDC, what
should the Crank marks be set to (TDC as well?? or 16-18 deg)?
My engine runs but I get excessive spitting back through both carbs. Indicating either a lean mixture or hopelessly retarded timing. The engine also
runs very fast and loud..
Any help in laymens terms would be much appreciated
Rob
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darrens
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| posted on 24/7/06 at 07:40 PM |
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I think from memory on a 2ltr pinto ignition timing should be at 4 degs (pre 85) and 6 degs (post 85).
So:-
Align the cam pointer with the mark on the head, put the bottom pulley pointing at TDC and fit cam belt. (making sure they don't move)
Mark the bottom pulley with a white marker or summat at on of the two figures above (which ever relates to yours).
Start up engine and adjust timing with strobe/dizzy to get the white mark to line up with the crank pointer.
Hope that helps
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RobBrown
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| posted on 24/7/06 at 07:51 PM |
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Thanks, I think the key point there being setting both markers to TDC, before refittig the belt. I had been setting the crank pointer to 16degrees,
then playing around with the dizzy.
I like it when the answers are simple!
Ta
Rob
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MkIndy7
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| posted on 24/7/06 at 09:13 PM |
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You mention its a 300 Deg cam,
I presume this is a lot wilder than standard cam?
In which case u'll need a Vernier cam pully and a timeing disk (for the crank) to set it up properly as there are no marks on the vernier to
line up with the marks on the head.
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jollygreengiant
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| posted on 24/7/06 at 09:13 PM |
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quote:
Originally posted by RobBrown
Thanks, I think the key point there being setting both markers to TDC, before refittig the belt. I had been setting the crank pointer to 16degrees,
then playing around with the dizzy.
I like it when the answers are simple!
Ta
Rob
If you look you will find that there are 3 markers.
Crankshaft/block - deep cut in pulley/pin or line on block.
Cam pulley/head - pointer on pulley back plate/divot on head.
and the one most don't realise about
Rotor arm/distributor body - point rotor arm to mark on distributor body mounting face that cap sits on (indicates No 1 cylinder). (This gives basic
static timing good enough to start and then set with strobe light when running.)
Hope this helps.
Enjoy.
Beware of the Goldfish in the tulip mines. The ONLY defence against them is smoking peanut butter sandwiches.
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DIY Si
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| posted on 24/7/06 at 09:23 PM |
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To use a 300 degree cam, you'll need some vernier pulleys. You'll never get the timing right with the standard pulleys, as they only allow
adjustment by a tooth on the belt, whilst you need a much finer adjustment to utilise the cam(s) fully.
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RobBrown
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| posted on 24/7/06 at 09:52 PM |
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I only recently became aware of the tdc mark on the dizzy housing. It might have been from a previouly posted topic here.
My mistake was trying to set the advance using the crank pully markings.
There are no vernier pulley's on ebay at the moment, although I have seen them before for around the £45 mark.
Burton want £70+ 
Ralley des want £65
Any recommendations for getting hold of a cheaper one.
Thanks
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DIY Si
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| posted on 24/7/06 at 09:54 PM |
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They seem to be one of those bits which everyone needs. Once the cams are timed correctly you can then easily sort the dizzy and away you go.
You'd be amazed at the difference 2-3 degress on the cam can make on power/running.
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mark chandler
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| posted on 24/7/06 at 10:14 PM |
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Vernier win my vote for the cam, this needs around 5 degrees advance to retrieve some mid range.
Also are your carbs bolted tightly, they should 'float' on the rubbers. You use special spring washers and just nip them up. overtighten
and they will dribble and leak as the fuel froths in the bowls.
Regards Mark
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TangoMan
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| posted on 24/7/06 at 10:33 PM |
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Who built the engine
As you don't seem too certain of the method to set cam timing, is it fair to assume you did not build the engine. If not I would speak to the
builder before going any further. Contrary to popular belief just changing a cam does not mean you require a vernier pulley. The cam timing will need
to be measured first to verify what you have. Then you have options of 1) Leave it as it is 2) Fit offset dowels to adjust to your preference 3) fit a
vernier and dial in as required.
There will also be differing opinions on the preference for cam timing. Some will say advance it, some willl say retard it. The outcome will always be
a compromise so it depends how you intend to drive it. A good day on a roiling road will pay dividends on playing with cam timing.
As has been said, there is a notch in the dizzy to help set static ignition timing but this really needs to be done running to fine tune. With the
engine at TDC on the crank pulley with both valves closed on cylinder no.1 the rotor arm should be pointing somewhere back towards your passenger door
in line with the small notch out of the dizzy body.
Don't you just love cars!!!
Summer's here!!!!
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MikeRJ
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| posted on 25/7/06 at 12:14 AM |
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quote:
Originally posted by RobBrown
There are no vernier pulley's on ebay at the moment, although I have seen them before for around the £45 mark.
http://cgi.ebay.co.uk/Ford-Pinto-alloy-ajustable-vernier_W0QQitemZ230010811397QQihZ013QQcategoryZ72205QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
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DIY Si
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| posted on 25/7/06 at 10:27 PM |
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quote:
Contrary to popular belief just changing a cam does not mean you require a vernier pulley
Whilst this is indeed true, I've found anything less to be a waste of time, even if only for the ease of adjustment. Especially since I have yet
to fit a cam at what the manufacturer has said.
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RobBrown
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| posted on 8/8/06 at 08:12 PM |
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Got one...
I think the best 60 quid I've spent in a long time. The ease of adjustment is phenomenal. Took 20 minutes to adjust instead of all day(and still
not get anywhere).
I was contemplating taking the engine to a rolling road or specialist to get the carbs and cam timed correctly.££££££££££
I managed to get the engine timed and running without the vernier pulley, but found that the response was a bit sluggish.
With the vernier fitted I was able to adjust the cam timing to the best position then adjust the dizzy. The response is now fantastic.
That's the extra motivation I need to get this baby through SVA
I now can't stop smiling. The buzz is back
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DIY Si
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| posted on 8/8/06 at 08:32 PM |
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Well done that man! See told you it was worth buying one.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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