Topic: Turbo Engine Ignition Systems?

[ZanVooden]

Alright needs some help understand/picking an ignition system.

I’ve been working on building a 76 CB750. I have a Turbocharger and have a cycle x 915 kit (as for the increased compression ratio, I have 77 CB750F cylinder head and cylinder block to mate the earlier lower end to benefit from the hemispherical combustion chambers of the later F models).

This bike isn’t a race bike or a purpose built drag bike. Will it see the drag strip, yes, probably 2-3 times a year maybe. Otherwise it’ll be a bit of a show piece and occasional rider.

So I’ve been doing a lot of reading on different ignition systems and having a hard time deciphering what is going to be best for my application.

I know Jim F. here has the MSD MC-4. This seems to be the best system out there for racing and such and also seems to be the most complicated and expensive.

The Dynatek 2000 seems pretty basic (and questionable reliability), but I saw reference somewhere that it could be run with a boost sensor but haven’t been able to find anywhere to confirm that.

Dynatek also has an ARC-2 CDI ignition, but I have no idea of it would work for my situation.

And then there’s the CycleX PowerArc ignition. This system seems very customizable, but not sure how to incorporate a boost sensor (or what kind of boost sensor) into it.

I don’t have any experience setting up and tuning an ignition system like these, so that’s why I’ve come here. Its also why I’ve looked into other alternative over the MSD.

I’m just looking for a little direction and feedback from the experience here.

Thanks,
Dave

[TurboD]

I am building a similar combo myself. I am going with what I know and what I know works. Ignition systems can be as simple or as complicated as a person wants.

I am going with a basic Dyna S and coils (possibly stock). I built a turbo Kawasaki that went 8.6s @ 160 with a Dyna S and STOCK coils, that's it. No fancy this box or fancy that box. The concept of ignition firing is pretty basic.

[Bill/BentON Racing]

Nice pic!  Mine has Dyna S and Martek coils... thats it...at least for now, works fine
For what Im doing with it. Bill

[Jim F]

I am building a similar combo myself. I am going with what I know and what I know works. Ignition systems can be as simple or as complicated as a person wants.

I am going with a basic Dyna S and coils (possibly stock). I built a turbo Kawasaki that went 8.6s @ 160 with a Dyna S and STOCK coils, that's it. No fancy this box or fancy that box. The concept of ignition firing is pretty basic.

May I ask how much boost you were running and what did you have your timing set at. also did you run race gas?
thanks
Jim

[TurboD]

Jim I was running right at 25-6 pounds, total timing was 28 degrees.

My street bike below has a completely stock ignition pickups and coils. Last checked, it made 210 rwhp with a bone stock 9K head running a easy 16 pounds of boost.

[Jim F]

Alright needs some help understand/picking an ignition system.

I’ve been working on building a 76 CB750. I have a Turbocharger and have a cycle x 915 kit (as for the increased compression ratio, I have 77 CB750F cylinder head and cylinder block to mate the earlier lower end to benefit from the hemispherical combustion chambers of the later F models).

This bike isn’t a race bike or a purpose built drag bike. Will it see the drag strip, yes, probably 2-3 times a year maybe. Otherwise it’ll be a bit of a show piece and occasional rider.

So I’ve been doing a lot of reading on different ignition systems and having a hard time deciphering what is going to be best for my application.

I know Jim F. here has the MSD MC-4. This seems to be the best system out there for racing and such and also seems to be the most complicated and expensive.

The Dynatek 2000 seems pretty basic (and questionable reliability), but I saw reference somewhere that it could be run with a boost sensor but haven’t been able to find anywhere to confirm that.

Dynatek also has an ARC-2 CDI ignition, but I have no idea of it would work for my situation.

And then there’s the CycleX PowerArc ignition. This system seems very customizable, but not sure how to incorporate a boost sensor (or what kind of boost sensor) into it.

I don’t have any experience setting up and tuning an ignition system like these, so that’s why I’ve come here. Its also why I’ve looked into other alternative over the MSD.

I’m just looking for a little direction and feedback from the experience here.

Thanks,
Dave

Hi Dave
Yes the MSD MC-4 system is complex but once you go in and see what it does and get to know the ole gal then shes not so bad
I run the basic ignition also, Dyna 2000 pick ups with the Dyna 2000 rotor, Dyna coils. I do have the MSD Boost sensor plugged into
the MSD box. With the software that you download from MSD, and its free, you can program a lot of different parameters. Yes its great for a full
blown drag bike.  Mine is a street bike and it will see some 1/4 mile runs but for the most part, a street bike. I also wanted to run pump gas, keep it static timed at 34 to 36 degrees,
and still run 8 to 10 lbs of boost, and not detonate or  blow the motor apart, thus the boost sensor. I can program how much timing to take
out of the ignition per pound of boost. With my bike I will start at 2 degrees per 1 pound of boost (I can program it to 1/2 degree increments) and go from there. Yes I am being very safe and this system is way over kill for what I want it to do. If you go back and look at what I put in my motor compared to what other people or running and they are running way more boost than I will ever see with a lot less. So it all boils down to how safe you want to keep your build and whats going to happen when that boost gauge begins to stir..........good luck and post plenty of pictures

[Bill/BentON Racing]

Nice "STREET" bike ! WOW, bet you don't get outrun...much if at all! Love it! Kawasaki BOTM!

[ZanVooden]

Thanks Jim.

So with the Dyna 2000 system, is it just a set ignition curve that retards the timing based on RPM? Or is there a pressure transducer that can be tapped into the intake manifold to relay boost pressure to retard ignition timing?

[Jim F]

Thanks Jim.

So with the Dyna 2000 system, is it just a set ignition curve that retards the timing based on RPM? Or is there a pressure transducer that can be tapped into the intake manifold to relay boost pressure to retard ignition timing?

Yes to your second question
the retard comes in when boost comes on threw this set up
it starts here at the monifold


and then goes in to the sensor


and to the box where its been programed with my lap top to take out a set amount of timing per pound of boost

[Mitchell]

I run the dyna 2000 on my 76 cb750 turbo. it has a wire that you can hook to to a boost presure switch. when the wire is grounded it will retard the timing 4,6,8,10,or12 degrees you just flip the switch to where you want it. with all that being said you can't set it to. say 1 degree per 1psi of boost. but what you can do id take your bike to a dyno and plug the ignition into a laptop and custom build your advance/retard curve. Google dyna 2000 instructions and read it, it will help you undetstanfd it better or call them there nicr people. to deal with. Timing retard will really depend on the fuel you run i run 8psi, timing lock out at 40 and retard 4 degrees at 4psi, been running for three years now on bone stock motor. sometimes i turn the retard off with good fuel with not a bit of trouble. you could convert it to run e85 and you would have a lot cooler intake,cylinder,and egt temps also a lot more protection from detonation and probably no need to retard the timing .


how much boost you going to run and what turbo?

[MRieck]

I run the dyna 2000 on my 76 cb750 turbo. it has a wire that you can hook to to a boost presure switch. when the wire is grounded it will retard the timing 4,6,8,10,or12 degrees you just flip the switch to where you want it. with all that being said you can't set it to. say 1 degree per 1psi of boost. but what you can do id take your bike to a dyno and plug the ignition into a laptop and custom build your advance/retard curve. Google dyna 2000 instructions and read it, it will help you undetstanfd it better or call them there nicr people. to deal with. Timing retard will really depend on the fuel you run i run 8psi, timing lock out at 40 and retard 4 degrees at 4psi, been running for three years now on bone stock motor. sometimes i turn the retard off with good fuel with not a bit of trouble. you could convert it to run e85 and you would have a lot cooler intake,cylinder,and egt temps also a lot more protection from detonation and probably no need to retard the timing .


how much boost you going to run and what turbo?

That's correct. I think that Dyna 2000 retard feature works better with a good size nitrous hit. Also.....you don't need the Dyna ARC unit. It is for large amounts of boost or nitrous. I have run one for a number of years on my NA busa....it picked up 2 HP.

[Mitchell]

Yes i agree the 2000 would most def be better for a nitrous app.

[Jim F]

And you don't need anything as complex as my set up to make these things work
What ever your comfy with

[ZanVooden]

Thanks guys. My plan is run around 8-12 psi. But we'll see what I can actually achieve once I get farther.