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Thu May 03, 2012 12:42 am

I have T4 in my 2276 turbo EFI engine in my buggy.
The question is I welded the weight to stop the advance and did the static at 24deg max and max advance. Now the bug his harder to start at cold start it takes about 3/4 cranks to get it going whie befor locking the distributor it start first crank.

Is that normal cranking after dist lock.

Thu May 03, 2012 12:59 am

Yes, this is normal. Remove the destroyed 009 and throw it as far away as you can. Get any distributor with the big two hose vacuum canister on it.
it works a bit as is, but should be modified for correct boost compensation - a canister from a Volvo 240/740 turbo or SAAB 99/900 turbo have the right boost curve. The distributor body may have to be clearanced slightly.
Recurve the distributor so you can have around 10-15 degrees at idle and maybe 30 at 3000 rpm, the canister will lower that when boost kicks in.
The specific numbers may not be correct for your engine, but is in the ballpark.
If you said 009 out loud, you must also brush your teeth.

Thu May 03, 2012 4:06 am

I never know why anyone would "Lock" a distributor when all you have to do is bend the weights to limit advance. Then you can start and run normally with limited advance to 24 degrees. I assume since it's now welded it's trash unless you can clean up the welds and get it to run normally again.

Thu May 03, 2012 4:16 am

By the way - find whoever suggested that mod and whap them along side the head..........

Thu May 03, 2012 4:29 am

Use the 009 - and then throw it away.

Thu May 03, 2012 5:28 am

You only have to go back 10 years or so and everyone seemed to swear locking the weights and timing to 24degrees was the be all and end all of ignition systems with turbo.

yamaduccis method is easy and effective, I did the same thing except instead of bending the tabs I tapped a thread into the stop and put the grub screw in so it could be wound in or out to vary the advance.
The screw even lines up with the inspection port in the side of the body.

Thu May 03, 2012 7:56 am

Put a toggle switch on the wire that runs from the fuse box to your 12v coil. Then when you want to start your engine turn the key and that should spin the starter then flip the toggle switch and it should supply juice to the coil and fire right up. This will help elminate the hard starting with a lot of initial advance.

Thu May 03, 2012 8:01 am

74 Thing wrote: Put a toggle switch on the wire that runs from the fuse box to your 12v coil. Then when you want to start your engine turn the key and that should spin the starter then flip the toggle switch and it should supply juice to the coil and fire right up. This will help elminate the hard starting with a lot of initial advance. or fix the addvance. witch may of been confuzed with lock the addvance. fix it in respects to it working right, not fixed to the plate.

Thu May 03, 2012 8:02 am

74 Thing wrote: Put a toggle switch on the wire that runs from the fuse box to your 12v coil. Then when you want to start your engine turn the key and that should spin the starter then flip the toggle switch and it should supply juice to the coil and fire right up. This will help elminate the hard starting with a lot of initial advance.

But it does nothing to correct incorrect ignition advance....

Real solution may be crank fire electronic ignition (Megajolt?) with MAP sensor so when you go on boost you get the ignition retard engine wants...

The world is moving away from distributors, they are crude and inaccurate... Go modern, go electronic...

Maybe CB performance crank trigger kit #2092

http://cbperformance.com/catalog.asp?ProductID=1884

And Megajolt ignition box....

http://www.autosportlabs.net/MegaJolt_Lite_Jr.

Or full CB Performance MEGASPARK...

http://cbperformance.com/catalog.asp?ProductID=1890

Dale

Thu May 03, 2012 9:48 am

No, but it corrects hard starting with a locked distributor which is the problem he is asking about.

Thu May 03, 2012 10:23 am

or add another pickup,start&run.

Thu May 03, 2012 11:38 am

Joel wrote: You only have to go back 10 years or so and everyone seemed to swear locking the weights and timing to 24degrees was the be all and end all of ignition systems with turbo.

yamaduccis method is easy and effective, I did the same thing except instead of bending the tabs I tapped a thread into the stop and put the grub screw in so it could be wound in or out to vary the advance.
The screw even lines up with the inspection port in the side of the body.

Really - OK well call me an idiot - I had never heard of such a thing (locking at 24 degrees)

Thu May 03, 2012 10:04 pm

Mine is locked out at 30*. Mallory hi-fire IV box to pull out timing under boost. Drives excellent off-boost.

Thu May 03, 2012 10:25 pm

A few basics on timing:

While starting, too advanced timing causes earlier back presure which in turn can stop the slow turning engine in its tracks since the flywheel has very little momentum.

While running too advanced timing can cause engine ping or even knock and possible severe engine damage. Too retarded and you lose torque. The problem is that the best timing is not fixed, it is constantly changing.

With increasing RPM's the engine needs more advanced timing, but a higher load requires the timing to retard. All stock distributors used vacuum advance to adjust for load since on a normally aspirated engine the load can be sensed by the diaphragm from either direct intake manifold vacuum or a special ported manifold vacuum signal that goes from high vacuum (low load, closed throttle) to no vacuum (high load, open throttle). The ported vacuum signal is an emissions device to retard timing during idling and to help with engine braking. DVDA's take that same principle a step further. Mechanical onlys, like 009s, don't adjust for Load and are designed to give best timing only at high load, full throttle. At part throttle low load they are retarded.

But with a turbo or supercharger, instead of getting a manifold pressure that goes from a vacuum to atmospheric, you get a manifold pressure that goes from vacuum to pressure. While the turbo is compressing more air into the engine the Load is increased even more, causing the flame to burn even faster. This requires the timing to retard to keep the engine from pinging and knocking. A normal distributor would not be able to compensate for the higher load due to possitive manifold pressure and will end up too advanced, possibly damaging the engine severely.

http://www.thesamba.com/vw/forum/viewtopic.php?p=5927285

To me using a locked distributor is a bad idea since there will only be a small RPM/Load area in which you get good timing. All the rest of the time you are going to be running too advanced or too retarded, both of which will take away precious torque and can damage the engine. A digital ignition system can be programed to provide exact timing at any RPM and Load combination. Mechanical distributors need to be adjusted with springs and weights to provide best timing at the highest load, that is, with full turbo pressure, but with the disadvantage of recieving poor economy at lower engine loads. Of course that doesn't matter when making a race car unless you plan to race around at part throttle. If you can get a diaphragm that retards the ignition with increasing possitive pressure then that could possibly work with a vacuum/mechanical (i.e. SVDA) distributor.

Thu May 03, 2012 10:30 pm

A locked dist works just fine for a turbo application. As stated before, you're missing out on the off boost timing adv. I bent the tabs on mine to lock it out, worked just fine, not permanent. Stepping up to a programmable ignition for turbo use is one of the best moves I made. Very cool set ups out there, and they give your motor what it needs.

Thu May 03, 2012 10:43 pm

The hyfire box has a start-retard feature. It takes 10* out below 500 rpm. So mine is starting at 20*. It starts within a second. Hot or cold. It only has 7:1 comp. I had mine locked at 24* and the motor ran cooler and had more off boost pep at 30*. I recently did some changes to the heads and intake, so I'm going to play with it more. More initial= more boost retard. Less initial= less boost retard. I have mine set right now at 1.6* per lb. of boost AFTER 2 lbs. I'm limiting it to 10 lbs boost. It takes a lot of trial and error to arrive at an optimum for the street, but once there it is awesome.

Any engine no matter how big is going to want to run at 3000-3400 rpm on the freeway. At that speed 24* ran hotter for me.

Thu May 03, 2012 11:55 pm

I'm sure there are people who are running locked ignition "and it runs just fine" but WHY would anyone want to put effort into having a more inefficient and possibly hard starting engine? I just dont get it.
A turbo engine is even more sensitive to vacuum compensation than a N/A engine.
Sure, distributors are crude - but why make them worse?
The owner of this thread unfortunately welded his 009 to lock it at 24 degrees and suffers because of it. If it had been left as is, it would have no problem starting and still have the same 24 degrees at some rpm.
With vacuum advance, it would be much crisper and efficient at off boost conditions.
Add boost retard and the engine just may have pretty good efficiency in ALL driving conditions.
This reminds me of another thread about running without shock absorbers.

Fri May 04, 2012 2:09 am

Amateur here who has been doing a lot of reading on this subject as of late.
Im over seas and have lots of time on my hands to research what I want for my car.
From what I understand...
Locking is just fine as long as your running a ignition box that allows for different timing when starting only.
This is pulled right off the instuctions of my MSD 7AL-3 box
I am going to be running a crank trigger setup.

Sorry its a long read but its worth it.

START RETARD
The Start Retard of the 7AL-3 is designed to ease starting on engines with locked timing, high
compression and a lot of advance. When activated, the timing is retarded 25°. Some engine
combinations benefit from this retard, while others may experience rough starting or starter kickback.
If your engine experiences roughness with the start retard engaged, the retard is not necessary.
When activated, the Start Retard function will retard the ignition timing 25° while the engine is cranking
which makes starting easier as well as saves wear and tear on the engine and the starter.

A. Switched 12 Volts
In this set up, the timing is retarded 25° only while the engine is cranking. Connect the supplied Violet
wire from the “Start-Ret” terminal on the 7AL-3 to the starter solenoid. This way, 12 volts is only applied
when the key or switch is in the cranking position. When the switch is released, 12 volts is removed
and the timing returns to run timing.
B. Constant 12 Volts
In this setup, whenever the ignition is turned On, 12 volts is applied and the retard function is activated.
The retard will be deactivated when the engine reaches about 1,300 rpm and will not occur again
until the ignition is turned Off. Connect the supplied jumper from the Start-Ret terminal to the Ignition
terminal of the terminal strip
function will only operate below approximately 1,300 rpm.

Fri May 04, 2012 9:10 am

Fine. And it would work the same if it was just left alone (no welding, bending or otherwise vandalizing it)

Fri May 04, 2012 4:27 pm

Boolean wrote: I'm sure there are people who are running locked ignition "and it runs just fine" but WHY would anyone want to put effort into having a more inefficient and possibly hard starting engine? I just dont get it.
A turbo engine is even more sensitive to vacuum compensation than a N/A engine.
Sure, distributors are crude - but why make them worse?
The owner of this thread unfortunately welded his 009 to lock it at 24 degrees and suffers because of it. If it had been left as is, it would have no problem starting and still have the same 24 degrees at some rpm.
With vacuum advance, it would be much crisper and efficient at off boost conditions.
Add boost retard and the engine just may have pretty good efficiency in ALL driving conditions.
This reminds me of another thread about running without shock absorbers.

I agree 100% Boolean! You are absolutly right!

Of course anyone could lock the timing even on a normally aspirated engine and it would "work", that is, it would still run. But what is the point? What would a guy gain from locking his distributor? Is there any advantage in creating a fuel guzzling engine to just let any potential gain in power just spew out the tail pipe? Or is there someone out there that has an engine that never changes RPMs and has welded the throttle in place? Would it not be better to just adjust the timing on a working distributor, even if just the total advance is the only thing adjusted, to a setting that does not allow for pinging at any RPM/Load combination?