Converting Big Block to Coil per Plug

[gmorris]

I'm going to convert my carbed 540 over to EFI this winter and am taking a serious look at the new Holley HP EFI setup. One nice feature of the system is it's ability to drive multiple coils and use a crank trigger to eliminate my MSD box and distributor. I would also likely use a cam plug with sync so I can go with sequential fueling and timing rather than waste spark.

Has anyone here converted a non-LS to multiple coil system? What coils did you use? Would standard factory or MSD LS style coils work fine? I would have to come up with a decent way to mount them near the head which will be a pain. Is there really much advantage over the twin tower coil waste fire setup that Holley uses as a default?

The other option is to use a dual sync distributor to do sequential fueling and just stick with the 6AL2 box I already have to simplify and save some cost. Is the stability of the crank trigger worth it? I still get timing control with the ECU that way.

[Blake Foster]

we did individual coils on the beaumont we are building that has a twin turbo 502. the differance is we used a motec ecu to control it all, it is a very advanced unit that does way too much stuff, we also used a AEM cam sync for the individual cylinder control another thing that is a bit different is a 12 pickup crank trigger for better signal.
we used stock GM coils from a ls shouldnt be long now til we know if it all works.
lots of extra wiring !!!

[Vegas69]

That's one of the things I like least obout the LSX motors is all the coils. I'd come up with a plan to hide them if it were me installing them. Another thing to consider is your fuel tank. I know you road race the car and starving the pump for a split second will cause you problems with injectors. You need to build a really good tank where you can get away with a little more with float bowls. I can certainly understand why you would want injection for drivability. Just wanted to throw out some thoughts.

[kennyd]

granatelli ( sp ? ) makes some killer valve covers for a bigblock to hold the coils and they also make some coil covers that match . i also want to convert my 502 to 8 coils but i want to keep the carb i have and not run efi . i was going to call MSD and see if they have a stand alone timing controll to run this set up .

[gmorris]

Originally Posted by Vegas69

That's one of the things I like least obout the LSX motors is all the coils. I'd come up with a plan to hide them if it were me installing them. Another thing to consider is your fuel tank. I know you road race the car and starving the pump for a split second will cause you problems with injectors. You need to build a really good tank where you can get away with a little more with float bowls. I can certainly understand why you would want injection for drivability. Just wanted to throw out some thoughts.

I'm already running a Ricks tank with A1000 in-tank and baffled. I know there have been some issues with Rick's on the track but typically only if run low.

[J2SpeedandCustom]

Originally Posted by gmorris

Has anyone here converted a non-LS to multiple coil system? What coils did you use? Would standard factory or MSD LS style coils work fine? I would have to come up with a decent way to mount them near the head which will be a pain. Is there really much advantage over the twin tower coil waste fire setup that Holley uses as a default?
The other option is to use a dual sync distributor to do sequential fueling and just stick with the 6AL2 box I already have to simplify and save some cost. Is the stability of the crank trigger worth it? I still get timing control with the ECU that way.

The MSD coils for the LS are not as good as the stock LS coils don't waste your money. You can do this setup a bunch of different ways. Figure out what type of crank trigger, cam sensor, iat, map, etc you are going to use.
Are you a system like an MSD box control timing, another box control fueling, another control transmission? Or are you looking for a 1 box solution?

You don't have to mount the coils on the valve covers, they can be behind the motor, on the oil pan, basically anywhere you have room.

[ohcbird]

First off,what EFI are you going to use? most of them can be made to drive the CNP setup, or are already able to do so. If you don't mind the extra wiring & work to mount/hide them, they'll be worth the trouble. Look at DSE's customer site to see how they hid the wires on Billy Chandler's 55, you could do something like this:

http://www.detroitspeed.com/projectp...andler-sub.htm

Here's a few more good reasons to run them:

1. Since you'll have 8 coils, the average heat produced by each coil can be shed quicker than one coil firing 8 cylinders. This adds longevity to the life of the coil.
2. The spark will be more controllable & predictable across the whole range.
3. The odds of all 8 failing & leaving you starnded is much lower than one coil dying & you being stuck somewhere.
4. Most of the EFIs can pickup the coil feedback signal & detect a bad coil.
5. No messing around at the back of the engine for timing (one the sync is set). Sit in your seat & adjust till the cows come home.

As J2 said, don't waste your time on the MSDs. The factory truck coils are the way to go.

[gmorris]

Originally Posted by ohcbird

First off,what EFI are you going to use? most of them can be made to drive the CNP setup, or are already able to do so.

As I said in the first post, I'm planning on trying the new Holley HP EFI setup which has the ability to drive seperate coils itself.

I keep waffling between just staying with the current MSD/single coil for now and then maybe doing DIS later or just going for it all now. Either way I will likely install the crank wheel this winter since I'm going to have the front accessories off to swap cams anyway. Getting rid of the distributor is appealing but I'm not convinced there is enough benefit to offset the cost/hassle since I get the ease of timing adjustment either way. Not having to mess with my distributor any more will be great.

Good to know the MSD coils aren't worth it. I was leaning toward the truck coils anyway.

[64duece]

I did the exact swap your referring about. MSD/FAST Dual Sync/HVC Coil over to the Holley DIS setup using 60-2 trigger, Holley wastespark coils and the 1x Cam Sync from EFI Connection.

The benefits I've seen so far: reduced spark scatter, slightly cleaner looking plugs and the obvious appearance advantage as all my components are mounted out of sight.

Having a 55 Chevy, I was able to mount my coils on the "splash pan" behind the front tire and route the plug wires accordingly. With the wastespark, it does make the plug wire routing abit cumbersome. There are a few good pics on Mike's site for coil mounting ideas.

http://www.eficonnection.com/24x/24x_CoilMount.htm

If you decide to use a distributor, I would recommend using it for the cam sync and running the 60-2 crank trigger to gain the spark accuracy advantage. You can always add coils at another time with this configuration.

[gmorris]

Originally Posted by 64duece

If you decide to use a distributor, I would recommend using it for the cam sync and running the 60-2 crank trigger to gain the spark accuracy advantage. You can always add coils at another time with this configuration.

That's what I was thinking...especially since I'll have all the accessories off this winter anyway mounting the wheel is easy. Is the crank trigger setup expected to be released around the same time as the efi systems? Do you mean use a specific cam sync distributor (like an accel dual sync) or can you just use the msd pickup as a cam sync? Did you gain any idle/low rpm improvement going to the DIS?