OK, I have been making concessions to deal with the "snuffing" the spark issue ever since I pushed past 15 psi boost. I am now down to 0.029" gap on the plugs and 26 psi boost, and it still "snuffs" the spark at just over 6000RPM.

I currently run the inductive pickup MSD distributor, MSD6AL, and the Blaster II coil that is tied into the aftermarket (FAST) ECM. Can someone provide the details as to what is required to move to something like a crank trigger with multiple coils (delteq, MSD, others?) or COP (coil on plug) arrangement?

I recall mention of Exotic Muscle making a MSD crank trigger integrated into the original diameter crank pulley (link???). How do you integrate this into the FAST system? How does this system trigger the individual coils? Can I ditch the distributor and simply install a "dummy" oil pump drive similar to what an LT1 uses (anyone seen this done?, am I going to chop down a factory HEI to use as a dummy shaft?)?

Any thoughts on the cost of the crank trigger set-up and the individual coils?

Will this definatively fix the spark issue with the very high cylinder pressures?

Thanks in advance,
Aaron

 

If you've got somebody you could borrow a 7al box from to swap the 6 with would be the easiest way to see if you're dealing with a weak ignition problem. You could also tighten the plug gap down to .025".

The COP or waste spark ignitions all require a cam sync to start the firing order.

MSD makes distributor plugs that drive the oil pump.

With a older FAST ecm you might also consider a MSD 7531 and completely take spark control away from the FAST.

 

SloR,
Thanks for the reply. I keep tightening the gap, and the problem gets better, but with the boost building proportional to the RPM, I am also increasing the boost, as I continue to gain on the RPM side. So... I am determined to fix the problem with the "snuffed" spark.

Can you provide additional detail on the cam sync? I believe I have a pigtail curled under the front carpet that is labeled cam sync. Where does the cam sync tie into the engine? Is this what ties into the crank trigger?

I am glad to hear that MSD makes the oil pump drive without the rotor drive. That is good news.

How about some more detail on the 7531, and pulling control away from the FAST system. To me it seems that this would be detrimental to what I am trying to accomplish. The advance is definitely based on boost and RPM.

Thanks again for your comments. And yes, I may get another set of plugs and try the 0.025" gap, but at some point, this has to affect driveability.

Aaron

 

You'll have an input for the FAST for a cam sync signal. It's needed to run sequentially with individual timing and fuel control. Basicly it's a sensor that that tells the ecm or the ignition module that the next crank sensor pulse is for the #1 cylinder.

Check out MSD 7531

The MSD ignition box actually is more capable than what's in your older FAST box. I would make the change to a crank trigger. MOS90 got one of the crank pulleys with integrated magnets.

Trying to do a COP or wastespark ignition with the FAST is going to require a seperate ignition control box. FAST now has a new one called the XIM. I haven't gotten any feedback on it yet.

 

ski_down_it uses a crank trigger with an Accel DFI system.

He offered some favorable remarks about them in this thread
- see post #4

A photo of it installed appears in the link below.

http://www.azzatochips.com/06_434/Motor_kael004.jpg

A review of past threads and/or a PM might yield further helpful
insight.

.

 

Slalom,
How about some detail and pics on Sony's car in this thread (don't want to over run someone else's thread). I am interested in his COP (coil on plug) setup.

Thanks,
Aaron

 

I replied in a PM prior to noticing this post.

Hopefully SonnyinVA can drop by with some info and some pointers
for you.

.

 

you already have a Crank trigger, and you are using fast?

Why not get the Cam Sync Sensor/ oil pump drive

MSD 8514

Then Buy a F.A.S.T. eDIST and run the LS1 coil packs..

I have the eDIST, I just need the Cam and Crank Sensors, then I should be able to get my L98 to run with Coil on Plug..

 

FAST discontinued the eDist. You'd need to find a used one. Was replaced by the XIM.

You can use the existing distributor as a cam sensor by removing all but 1 tooth off the reluctor ring.

You can use a MSD crank trigger setup if you shim your accessories out 3/8". Not the easiest thing for Aaron to do. Integrating triggers into the crank pulley would eliminate the shimming.

 

There is also Flywheel Trigger Ignition - there might be more room
for the trigger at the rear of the block in a SC C4.

I do not know of shrink-wrap kits for Chev V8's. However, if these
don't exist, the components and knowledge that would be necessary
to adapt FTI to the SBC are out there if someone decided the time
and money to do so would be worthwhile.

.

 

Really?!?!? more info please..

I also could buy a dual sensor distributor (Crank and Cam sensors) then if I needed to stay with the single coil I could while working the kinks out of the other set-up.

I figured for the Crank trigger you would need to space out the accessories.. I really want to install the CNP on my L98, I think the dual dist. would be the best and use my eDIST

 

Ski_dwn_it posted awhile back about someone (March?) making a modified crank pulley that accommodates the crank wheel without having to space out the accessories. It wasn't cheap but it seemed like a nifty solution. I don't have the post handy, sorry.

 

I believe that Exotic Muscle is the one that has the crank trigger integrated into the crank pulley.

From what I understand, I will also need a cam trigger, how do I go about getting that signal? I would like to run it off the front of the cam, so that I could totally eliminate the distributor (save the dummy drive for the oil pump). Thoughts on how to do this? I would then add the idividual coils from MSD like Sonny has on his engine.

I would thing that combo should keep the plugs lit.

Thanks for the input, guys.
Aaron

 

If someone wanted to pursue the flywheel trigger ignition, I see
that MSD offers the parts.

qty 4 - PN 8277 - Magnetic Stud, 3/8"
qty 1 - PN 8276 - Non-Magnetic Pickup

As per the link for the studs, work is required to locate four of these
at 90º intervals. The pickup is the same as is included in conventional
crank trigger kits, just without the MSD brackets, fasteners and the
trigger wheel. If desired, there also appear to be smaller dia pickups
available.

As for Dale1990's remark about modifying a March crank pulley. With the
MSD studs, my vote is that this would be a fairly straightforward job for
a competent machinist to perform on an aluminum pulley (or the OEM
steel one for that matter.)

Find a location where it is possible to fit the mag pickup within proximity
to the pulley and fabricate a mount for the pickup. Mark the location
on the pulley in relation to #1 TDC and have someone install the four
studs at 90º intervals. By providing adequate adjustment in the bracket
for the pickup, minor errors in layout of the location of #1 stud can be
accomodated. Adding witness marks to help ensure the pulley goes
back into place in the correct location will help during engine reassy.

Unfortunately I have neither my car with its March pulley or the OEM
original to look at to evaluate how realistic the home-brewed trigger
is at the moment.

.

 

There's a couple of issues that come up with the cam/crank distributors. Most systems require the cam sync signal to happen within a certain window as compared to the crank signal. It isn't real easy to adjust with one of these distributors. The other thing that happens is that you have to very similar sensors in close proximity to one another and you and have crossed signals.

If you remove 7 of the 8 "teeth" off of a distributor you've set it up so that it will produce one signal per cam rotation. You've made it a cam sensor.

Mac at Fasttrack once told me he had catalogs of magnetic bolts to be used as triggers like Slalom just posted. Using those bolts, if you've got access to a mill and a rotary table, setting up your crank pulley for a crank trigger would be a piece of cake. Thanks for the link. I've been wanting to add a crank trigger to me car to take the crank signal away from the Dual Sync.

For a cam sync off the front you could machine the cam gear for something like this. universal cam sync You'd need to modify the front cover for the pickup.

 

SloR,
Thanks for the info. Give me your thoughts on modding the front end of the cam for the sensor. I had thought that the pigtail on the fast was a single wire, but I may be wrong. The universal kit has a two-wire sensor.
http://www.msdignition.com/images/2346_big.jpg
I would assume that you would mount the sensor into the timing chain cover (in my case 3 piece Comp cover, and then make a bracket to secure the magnet at a certain position ( I assume #1 TDC)

I would plan to use the integrated cranshaft pulley with built in magnets, and then place the trigger bracket on the low R (passenger side) of the engine.

I assume that the FAST will be looking for a signal that says when the crank puts #1 at TDC on both compression and exhaust stroke, and also looking for a signal from the cam sensor saying that it as at TDC compression stroke only. When both signals are read, then it adjusts the timing based on the timing map and then sends a signal to another control bog that could fire the individual coil on plugs. Am I understanding this correctly?

I appreciate the help.
Aaron

 

I like this, and I assume it will not matter the diameter of your trigger wheel, just as long as your 4 magnets are at 90 degree intervals?

Another option is to use a Vortec crank trigger and Sensor and the Vortec Timing cover..

but you would not have room for the double roller timing chain anymore

 

Does anyone have the link for the EM cranshaft pulley kit with integrated magnets and trigger / bracket?

Thanks,
Aaron

 

I'd be thinking along the lines of milling/reaming the cam gear for an interference fit on the magnet and then welding a threaded fitting into the cover for the pickup. It all depends on waterpump clearance.


The crank sensor needs to send a signal to the ecm in a window of 50 to 65 degrees BTDC on compression when using a crank sensor. For a V-8, the other 3 crank signals occur 90 degrees apart from each other. The cam sync needs to occur 20 degrees before the crank signal. The ecm sees the cam sync and then knows that the next crank signal to occur will be #1. Based off of the crank reference angle in the system config area it knows that the crank signal occurs at whatever is entered in the crank reference area. It then looks at rpm to see how fast the crank is rotating and delays triggering of the points output wire so as the spark will occur at the value you have entered in the spark timing map.

I haven't setup one of the XIM boxes yet so I'm not 100% on how it operates. My guess would be that the points output from the FAST would trigger the XIM which would then operate the coils.

 

P/N C1306 midway down here



Link provided by Mr6spd (2006-09-27)

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