help....still can't get the timing right....

MI95Cobra

New Member
Aug 20, 2006
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Oklahoma City
ok...i was told i was off 180* on my timing....so i took it back down to my timing chain...made sure i was timed...took out my #1 and had my harmonic balancer at 0*...then had m distributor reeset...it still turns over and backfires....it pissing me off....any ideas???
 
Good times huh, I just went through the same thing today. What ended up working for me was pulling the number one spark plug, bumping the motor and feeling in the spark plug hole eraser side first with a pencil until I got maximum height out of the piston (I pulled the pencil, bumped the starter and remeasured with the pencil until I got it right) after that point the rotor slightly clockwise of #1 cylinder on the distributer, tighten down the clamp enough where the distributer won't move when you go to start it, reinstall the spark plug and wire and keep your fingers crossed. Turn the key and you should be in business:nice:
 
The crank and cam are timed to each other

The dizzy is timed as well but it ain't the same as the crank/cam timing

Or course both need to be correct

I guess I'm saying you can have your crank/cam timed perfectly
and
Your dizzy could still be ... NOT in time.

Assuming your crank/cam time is like it should be

Lets focus on the dizzy

We got a 4 stroke motor ... right

The slug rises twice during those 4 strokes

Once to compress the a/f charge
and
Once to expel that charge after it is burnt

You place your finger over the #1 hole to ensure you don't use
the wrong tdc ... or the one that has the e valve open

If you know the slug is rising and feel no push of air
you then know the next rising of the slug is gonna be the one you want

When you first feel the push of air ... stop ... look at the hb ...
you will line it up on the tdc mark and stab the dizzy in place where
the rotor lines up with the #1 plug wire.

It should fire at that point ... then ... just set it to your spark value of choice
with your t-lite.

Grady
 
I had some problems with this when i first fired my 347. Make sure the car is cold and take your time. Get your finger in that spark plug hole and feel for that air coming out of the plug hole. It helps to have a friend with a breaker bar turning the motor over while you have your finger in the hole. Then follow the above steps.
 
when i took it back down and replaced the timing chain...so i made sure it was lined up right...then i went and made sure the roller rockers were torqued to specifications...i'm getting compression...it back fires....i need someone to turn it so i can put my hand over it i guess....a friend of mine is coming over later...thanks...also anyone got pics of where the distributor is stabbed?? i got a msd cap and rotor and after seeting where the rotor and distributor..the msd sign is on the other side or at and angle...
 
i did't feel any compression when i put my finger over the hole....

Your pr's could be too long holding the valves off their seats
thus no squeeze.

Back to the dizzy thing and waiting for help

If you line up your hb on the tdc mark

Since you got two opportunities for the piston to go tdc

You're gonna be on one or the other stroke

1) Right on time and it fires right up
or
2) 180 out and it might start but rev up slow or bf

If you see 2 .........
You just spin the rotor to point in the exact opposite direction ;)

Grady
 
no...whats a compression checker...yes from a head and cam change out...i changed both out on my 92 gt a few yrs back...but i didn't have any problems timing it...

It checks the compression in a cylinder.

Some have a rubber tip you hold tight in the hole while cranking over
the motor and some have a threaded adaptor you screw in the plug
hole.

If your heads have been cut a bit or you're using a thinner hg
or even a bit of both, you might have pr's that are too long.

Grady
 
aaawwwgggg i give up....i still have nothin...and whats worse i almost killed the battery turning it over....i even check the starter relay...how much are compression testers??? should i just pay to have a mechanic set my timing???
 
i replaced the heads with some off a 93 cobra that had been valved and springed, milled, and ported...if that helps...

Jimmy

Think of a completely stock 5.0 motor that has never been taken apart

Now ... say you mill the heads 30 thousandths of an inch and put it
all back together with no other changes.

The push rods now push the valves 30 thousandths of an inch farther
off their seats.

True ... some of that measurement could be taken up by the range of
movement in the lifter ... but ... can you see how it might be possible
for the valves to he held off their seats because there is no longer
enough slack in the valve train and you can no longer build compression.

See ... the thing about peds is you have no ability to adjust anything
like you can with studs.

If you got too much or not enough slack in the valve train with peds you
gotta use shims or different size push rods.

To check the amount of slack on peds you get all setup to adjust a valve
and at the exact moment you find zero lash you should be able to tighten
the nut to its torque measurement in a certain amount of turns.

Depending upon the amount it takes or doesn't take will tell you if
you need different pr's or shims.

Sorry Jimmy ... I only worked with peds once and I don't remember
the specific turns or torque value but that info is easily found. I'm sure
some of the other guys will chime in with the part I forgot.

IMHO ... The most important thing here is you get a grasp on how
this works ... once you get a grasp on this concept ... it will become
obvious to you how you go about fixing it.

Let us know what you find.

Grady
 
grady...ok...by peds you mean pedestal rockers right??? i have roller rockers they are crane cam style with the ford stamped logo....how do i shime the rocker arms?? so i should get longer push rods you think??? i replaced all the push rods....but i got them for a 95 cobra...thanks jimmy
 
grady...ok...by peds you mean pedestal rockers right??? i have roller rockers they are crane cam style with the ford stamped logo....how do i shime the rocker arms?? so i should get longer push rods you think??? i replaced all the push rods....but i got them for a 95 cobra...thanks jimmy

Jimmy heres what I'd do :)

Do a search here for the correct procedure to setup up valve train
geometry in the usual places like forums and faqs.
also
The big cam companies like Crane, Comp, Isky, etc have excellent
info about getting your vt right. The info you find will tell you the
procedures you preform to ensure you got the correct springs,
pr's, shims, preload, and so forth.

Since your heads have been cut down a bit, you need to check all
that stuff.

You are gonna see topics like spring or coil bind, clearance
between the bottom of the rocker and the spring retainer, roller
travel distance/position across the valve tip, and more which is
commonly called vt geom.

In a nut shell, you have to ensure all that stuff is right before you
adjust the valves.

Pedestal or as some call them, bolt down rockers were dreamed
up by Ford to cut down time on the assembly line. Good for them
but bad for hot roders as they have no flexibility in adjustment.

Since each oem motor uses the exact same heads, valves, springs,
pr's, hg's, the vt geom and vt clearance never changes thus the
need for valve adjustment is not needed so it saved time on the
line for the workers putting the motors together.

I know the info I've shared is brief but its certainly enough for
you to see the importance of your vt being like it should be.

Grady