Timing adjustment - Don's crazy cams

[Dutch]

I'm looking is someone might know the correct timing for Don's Crazy cams. I read in an article it should be :

"When running Don's Crazy Cams, adjust your timing from 13 degrees to 20 degrees."

Can anyone confirm this?

All this because I'm having starting issues, once started the car runs fine.



After a full and successful engine rebuild if found out my DMC has some history.

I found an article online about my car : http://www.projectvixen.com/dmcnews-archive/msg79587.html

Currently I've got about 1200 miles on the rebuild but am having starting issues. I've done the following:

New battery
New fuses
Upgraded wiring
Cleaned and checked fuel pump (although I'm starting to get a humm in the center near or on the accumulator, when the car has run for a good while + 1 hour)
Checked starter
New distributor cap and rotor


The car has HEI ignition upgraded spark wires, spark gaps, bypassed resistor, HEI Coil MSD2, but getting an orange spark (and looking to upgrade to a duraspark ICU).

Any assistance would be greatly appreciated.

Thanks,

Dutch

[content22207_2]

Advancing base ignition time typically makes an engine harder to start.

Since your engine runs well once started, I would look at cold engine settings first (especially if the spark plugs indicate good fuel burn, ie: dry caramel color on the ceramic insulator).

K-Jet gurus can give you several tests to perform, but bare minimum I'd check the cold start injector, cold engine control pressure, and cold engine vacuum advance cutoff.

Bill Robertson
#5939

[Dutch]

Hi Bill, I performed the tests the k-jet gurus mention, switching the plugs. Checking injectors. Checked all vacuum lines. Spark gaps, valve timing, compression test (dry and wet). All seem good.


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[content22207_2]

What do the spark plugs look like?

What happens if you pull the PCV breather hose off and squirt some starting fluid into the air filter housing before cranking?

Bill Robertson
#5939

[content22207_2]

You didn't mention the cold start injector -- make sure it sprays while cranking (if your engine starts right up with starting fluid I would definitely test the cold start injector).

Bill Robertson
#5939

[Dutch]

Spark plugs are dry and light brown/tan. The spark is orange, so not good) I haven't tried the fluid.

I can get it started using a jumper cable with a second car. Once it's run I can usually start it again. But then it won't start again. So it's not a cold / hot start issue. (First thing I replace in the car was the accumulator).


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[content22207_2]

I can get it started using a jumper cable with a second car.

I'd start there (load test the battery).

Bill Robertson
#5939

[Dutch]

Battery is brand new (optima yellow top deep cycle) . Its fully charged.

I'll check the cold start injector and post an update.

[DMCVegas]

Exactly what are the starting issues that you're having? No cranking? Turns over but won't start?

[Dutch]

It turns over, but wont start. Using a jumper I can get it started after several tries. then it runs good. The starting spark is orange. running I dont know.

[content22207_2]

What is voltage into the coil while cranking? (Even the factory configuration bypasses one of the external resistors while cranking to increase coil voltage).

Make sure your engine is well grounded. Factory configuration is a daisy chain of braided strap (some owners have reported terminal failures on their braided straps), through the frame, then battery cable attached to one of the trailing arm bushing bolts. All of my vehicles, including a school bus, have been rewired with dedicated ground wires from the engine directly to the battery.

Bill Robertson
#5939

[Dutch]

Bill, very good point. I was also in the process of checking that. Thanks for the suggestion.

[content22207_2]

Block ground on one of my pickup trucks (original frame ground, which is still grounding the cab, lights, etc) is on the other side of the brass bolt. From the factory Ford used a braided engine strap similar to DeLorean.

41087

Bill Robertson
#5939

[David T]

Bill, very good point. I was also in the process of checking that. Thanks for the suggestion.

You should do what you have to do to get a blue spark. Maybe try another coil. Bypassing the ballast resistor is not a good idea unless you are using a coil that specifically says it does NOT require an external ballast resistor. Advancing the initial base timing too much makes it very hard for the starter. High performance cams that have a lot of lift and overlap typically do not make much vacuum at low RPM's making it hard to start the motor. In extreme cases you have to increase the idle speed so it will run. Others that have tried high performance coils have seen them die early deaths and went back to the stock coils.

[content22207_2]

Others that have tried high performance coils have seen them die early deaths and went back to the stock coils.

Myself excepted of course. I've been running the same Pertronix coil more than a decade no problem.

Any high winding (performance) coil with 1-3 ohms internal resistance will work perfectly well at full charging voltage. Hot rodders have built an entire industry around them.

Bill Robertson
#5939

[Dutch]

David, I read about that. The coil that was in the car is a MSD 2 HEI coil (according to spec it doesn't need the resistor, it's actually supposed to perform better at higher voltages)

http://www.dmctoday.com/showthread.php?284-How-to-Upgrade-to-High-Energy-Ignition-%28HEI%29

I've rechecked the wiring, cleaned and contacts and putting the starter back now. I'll add extra ground to the engine.

Additionally what I have, but haven't tested is:

I have a new MSD 2 coil, and a new ICU (the duraspark with custom harness to plug straight in without any cutting or changes)

[content22207_2]

custom harness to plug straight in without any cutting or changes)

Where did you get that? I've only made them for Byrne Heninger, Steve Rice, Farrar Hudkins, another owner in Louisiana, and myself.

Bill Robertson
#5939

[Dutch]

I followed your instructions very carefully from :

http://www.dmctoday.com/showthread.php?97-Ford-Duraspark-Ignition/page7

41090

Got the duraspark at a local autozone, The harness / connectors from a local junkyard (old ford ranger $6) and a the connector (VOLVO 74-84, 240 SERIES IGNITION CONTROL MODULE BOSCH # 0 227 100 005 NWL117) for $25 off of ebay.

[content22207_2]

That Bosch module has 6 small pins (versus 4 small and 2 wide in the harness connector). It will still work if you file off all but the center orientation key and cut the ends out. A little extra work, but not too bad:

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Bill Robertson
#5939

[Dutch]

Excellent. Thanks so much for that tip.

[FABombjoy]

Does the Duraspark have a pin to add some spark retard like certain GM HEI modules do? If you really are supposed to set base timing to 20deg such a thing may help with hard starting.

There are a few other things in that DML link that give pause and I would probably call Don to confirm that base advance figure.

FWIW I've tested at least 13 degrees of electronic spark retard without phasing issues - spark falling off, jumping posts, or the like - and it seems like there is room for a touch more. Exhaust will start to get hot, tho :D

[content22207_2]

Spark timing is under control of the distributor. All the module controls is dwell.

Duraspark has a sense wire for a starting signal, which increases dwell to 56 degrees. Compensates for lower voltage from the battery while cranking.

At idle Duraspark dwell is 50 degrees (versus 44 degrees for the stock Bosch module).

Bosch module dwell increases to 46 degrees at 3,000 RPM. Duraspark dwell *DECREASES* to 44 degrees at 3,000 RPM. It's part of Ford's philosophy to maximize fuel burn (let the coil discharge as long as possible before recharging). Ford also increased size of the rotor blade to maximize contact time with each cap terminal. That's why Duraspark distributor caps are such large diameter.

Bill Robertson
#5939

[SS Spoiler]

Who is crazy Don?

[Dutch]

excerpt from : http://www.projectvixen.com/dmcnews-archive/msg79587.html

High Performance Cam Shafts (I call them "Don's Crazy Cams")
developed by Don Steger from DeLorean Motor Company - California
(formerly DeLorean Motor Center)

[DMCMW Dave]

When did (the other Dave S) sell this car? I know he's been quiet for a while but I didn't realize he sold it.

[Dutch]

According to my paperwork it was sold (by Dave) to the previous owner in Dec of 2013 and I bought it from him in March of Last year.

The car does come with some incredible paperwork, originating back to the original window sticker and bill of sale (including dealership receipts, tags and title papers, maintenance receipts)

[Patrick C]

According to my paperwork it was sold (by Dave) to the previous owner in Dec of 2013 and I bought it from him in March of Last year.

The car does come with some incredible paperwork, originating back to the original window sticker and bill of sale (including dealership receipts, tags and title papers, maintenance receipts)

You have quite an incredible car that's had a lot of love put into it! I'm glad it seems to be in the hands of an owner who will appreciate it's unique history!

[DMC5180]

When did (the other Dave S) sell this car? I know he's been quiet for a while but I didn't realize he sold it.

Perhaps you were thinking Dave Stragand and the famous Project vixen Twin Turbo 05927.

Perhaps the car in question belonged to Dave Watts. (Dutch states his VIN 01729)

[Bitsyncmaster]

Perhaps you were thinking Dave Stragand and the famous Project vixen Twin Turbo 05927.

Perhaps the car in question belonged to Dave Watts. (Dutch states his VIN 01729)

Dave Stragand drove his D to DCS2014.

[Patrick C]

Perhaps you were thinking Dave Stragand and the famous Project vixen Twin Turbo 05927.

Perhaps the car in question belonged to Dave Watts. (Dutch states his VIN 01729)

Ahhh. I certainly was thinking of this being Dave Stragand's car. The link to projectvixen.com on the first post confused me. My mistake.

[DMCMW Dave]

Ahhh. I certainly was thinking of this being Dave Stragand's car. The link to projectvixen.com on the first post confused me. My mistake.

Me too.

[jmettee]

So to answer your question, I spoke to Don Stager before buying the cams for my car. I found it odd that on 2 phone calls he couldn't tell me specific values for lift, duration, or recommended timing. Those are crucial pieces of information for a product you're selling. I believe he told me something crazy like 24 degrees which is off the timing plate scale. I run my car at 17 degrees because I have stock exhaust manifolds and aftermarket muffler. If I had headers I may push to 19 degrees, but I'm not sure if that is common or not since I don't have that setup. Someone told me that 19 degrees was ideal for those cams with fully aftermarket headers/exhaust.

[dmruschell]

I can't speak for Don's cams, but Josh from DPI has said on the forums that advancing the timing to 17+ will probably require the use of higher octane gas. I'm running my DPI cams at right around 15-16 degrees initial advance and they run great on 87 octane. That's as close as I've come to an official word on advance with performance cams in my internet searching.

[Dutch]

Thanks for all that have contributed.

I'm testing to see where it runs best and will post an update when I've had the best results.

On a side note. I also had start and cutoff issues. The culprit was the tachwire. It was stuck between the distributor and the engine block. Every time i would tighten down the distributor it would cut off and over time it was hard to start. The hard to start was because the distributor would move over time (duh) because it couldn't be tightened down completely. The cut off was because the tachwire was clamped between the distributor and the engine and had over time (due to friction) cut through the outer mantel and thus would short when i would clamp down the distributor.

41459

[David T]

Thanks for all that have contributed.

I'm testing to see where it runs best and will post an update when I've had the best results.

On a side note. I also had start and cutoff issues. The culprit was the tachwire. It was stuck between the distributor and the engine block. Every time i would tighten down the distributor it would cut off and over time it was hard to start. The hard to start was because the distributor would move over time (duh) because it couldn't be tightened down completely. The cut off was because the tachwire was clamped between the distributor and the engine and had over time (due to friction) cut through the outer mantel and thus would short when i would clamp down the distributor.

41459

One way to set the timing is to "power tune". What that means is you set it to the original spec, 13 degrees BTDC and in increments of about 2 degrees you advance it till you get pinging or detonation and then back it up a couple of degrees. To test for pinging you have to get the motor up to operating temperature and go for a drive and then load the car like going up a hill in a high gear. Very dependent on the fuel, the temperature, the car's load, etc. This does not take into account any changes you could do to the mechanical or vacuum advance. You typically want the advance in as quickly and as smoothly as you can. With modified cams you can probably put in more than 40 degrees.

[Denver DMC]

I just rebuilt my engine with Don's cams. First 600 miles at 20 degrees BTDC. Just bumped it to 24 degrees using a gas analyzer to tune . Good so far. Car running smoothly with no hunting. Power really comes on at 3000 RPM. I will keep the group posted.

PS - I am at altitude - Mile High City.


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[Denver DMC]

PS - I run premium gas.


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[Denver DMC]

. . . and DMCH Stage I headers.


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[dmruschell]

I just rebuilt my engine with Don's cams. First 600 miles at 20 degrees BTDC. Just bumped it to 24 degrees using a gas analyzer to tune . Good so far. Car running smoothly with no hunting. Power really comes on at 3000 RPM. I will keep the group posted.

PS - I am at altitude - Mile High City.


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Did you limit the total mechanical and vacuum advance? You might run into pre-detonation issues at part throttle and high roms WOT if you don't.

I just went through this issue on my Buick. Stock initial timing was 4 degrees BTDC. My mechanic adjusted it to 13 degrees BTDC to give it more power. However, connecting the vacuum advance caused it to ping (can be felt as an occasional miss) at cruise and it pinged like crazy at WOT above 4000 RPMs. This is because the distributor was designed to be set at 4 degrees BTDC, and the mechanical timing curve and vacuum advance were designed around that initial timing setting. The vacuum advance added the necessary advance to bring that initial 4 degrees to what the engine needs at cruising throttle, and the mechanical advance also increased the advance as the RPM increased with the curve still based around the 4 degree initial advance.

With the initial advance increased to 13, the vacuum and mechanical advances each increased the advance too much - to the point of pre-detonation - and should have been adjusted by limiting the advance of each. Remember, the engine only sees the initial advance at idle. Whenever you're driving the car, the mechanical and vacuum advance mechanisms are at work and should be adjusted to prevent pre-detonation. Many people with classic cars set their timing by knowing the total mechanical advance they want to achieve at high RPMs, and then let the initial advance fall where it may based on the high RPM advance.

I adjusted my Buick's initial timing to 4 degrees, connected the vacuum advance, and I get better part throttle response and no pinging at high rpms. The engine has never run better. Midrange WOT torque went down, since there's less mechanical advance involved. That can be fixed by increasing initial advance, recurving the distributor, and limiting the mechanical and vacuum advance. But that's more work than I want to do at the moment.