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-   -   msd 6a and jeffs ddlis dyno? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/msd-6a-jeffs-ddlis-dyno-101018/)

khaine_d 07-30-02 01:53 PM

msd 6a and jeffs ddlis dyno?
 
Did anyone ever dyno the msd 6a box with coils verses the direct dual leading ignition system from jeff? just curiouse I've seen hints but not a def answer. I would like to see the results.. IT's very simular, I just would like to see the results thanx khaine

peejay 07-30-02 02:01 PM

Yes, it's been done.

The HP difference is minimal from MSD to Jeff's setup to stock.

However I am thoroughly in love with the MSD system because of what it does for cold driveability and low-RPM driveability.

Jeff20B 07-30-02 02:21 PM

Yeah, there's been a few dyno runs comparing them. Geo set his timing for the MSD which gives a different reading at high RPM than the stock ignitors. That means to get optimal performance on DLIDFIS, the timing should have been reset. He also used coils that are made to benefit from a CD spark more than a kettering spark. He also didn't have time to change his AF mixtures (I'm not sure it would have made much of a difference, but still, these are the facts).

Yep, very similar performance without adjusting anything. Not bad, if you've seen how I arrived at my original conclusions. :eek:

peejay 07-30-02 02:43 PM

Now work in a rev limiter in your setup and make it fire multiple sparks below 3000rpm and also make it send 450v to the primary windings of the coils (under ALL conditions) and then it'll be perfect. :)

Jeff20B 07-30-02 03:00 PM

A rev limiter on L and T, multisparks below 3000rpm (and maybe above), 450v with super long duration at all times and all RPMs, and it would be the best ever. I hear yah!

Directfreak 07-30-02 04:03 PM


Originally posted by peejay
Now work in a rev limiter in your setup and make it fire multiple sparks below 3000rpm and also make it send 450v to the primary windings of the coils (under ALL conditions) and then it'll be perfect. :)

Originally posted by Jeff20B
A rev limiter on L and T, multisparks below 3000rpm (and maybe above), 450v with super long duration at all times and all RPMs, and it would be the best ever. I hear yah!
Isn't what Peejay wants, - simply in a red box?

Jeff20B 07-30-02 04:24 PM

Nope, cause it has short duration sparks and costs a lot.

MIKE-P-28 07-30-02 04:29 PM

NOS NOS NOS get the MSD lol :D

peejay 07-30-02 06:39 PM

$250 is way worth it for the excellent cold driveability. After the MSD install, the car NEVER flooded out on a subzero start. I call that worth the money! Before the MSD, it would barely run with the choke all the way out, and if you pushed the choke in it wouldn't have enough engine speed to run. With MSD, just yank the choke, fire it up, and it runs smoothly at good RPM.

Jeff20B 07-31-02 01:12 AM

$25 and a little time is worth it. My winter days (nights) weren't below zero, but my engine would always start up fine with the choke part way out. Infact, I don't like to run mine above 2500 RPM when cold, let alone the recommended 3500 or whatever it is. After it fires I just lower it to 1500 and it's nice and smooth. I don't even wait for it to warm up. I just get in and go.

I think the differences between our setups is that mine is using an Hitachi carb on a seperate runner manifold. This lets me have smaller ports than you 12A guys. Could that be the reason?

peejay 07-31-02 11:21 AM

Well keep in mind that subzero means that with the MSD, having the choke all the way out would only let it rev at about 1200. :eek: Without the MSD it wouldn't want to run about 800 or so and of course it would flood out running that rich at that low of an RPM, so you'd have to sit there and blip the throttle for five-ten minutes until the engine could run on its own.

Jeff20B 07-31-02 01:19 PM

I often wonder what it would be like for my engine in subzero weather. I hope I never need to find out. 8O

khaine_d 07-31-02 03:25 PM

Well guys.. I have a 12 a, the msd looks like an easier install, I would love to try them both, but like my sig says I'm a mechanical idiot. Jeff if you could break it down alittle more for me, like insert tab a into slot b then smack yourself in the back of the head when you realized that slot b was actualy slot d.. ect I would wire it up.. basicaly step by step. whats the red and green on your diagram represent? and well thanx for all the info=8c)


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