Found a little mph

[6667fan]

Engine has had a stumble at top of track forever. Sometimes comes on in third. Prior to going to track I bought another phased rotor from MSD. Had to move it 11• in one direction to get the spark jump to a cap terminal not stretched out. Stumble was not present and car went 127.15.
Previous mph was 125.75 +/-.
Was hoping to find a 10.4 but 60’ was off by over a tenth and I did not power shift.
Hoping to get back before end of season

[Stangman]

Nice find.

[Barry_R]

That's a significant MPH gain

[6667fan]

 A little back story on trying to figure out the stumble. I showed the guys at RPM Data Logging a screenshot of the scattered rpm engine was experiencing. Randy took one look at it and said “ ignition slop”
So let’s try to find it. Is it one component or a cumulative stacking of slop from cam gear, distributor end play, distributor top end play, box lameness, coil weakness?

I happen to already have a distributor at MSD being checked out. They had already worked on it and it came back with .032 of end play. Ford spec for that is .020-.030. So it went back. I’m trying to get through to the first guy that I want this unit at .025. “ we will put it to factory spec “ 🙄
Let me have a supervisor please. I try to get him to agree to have it put it at .025 which eventually he agrees to.

So since I have him on the phone I ask was why is it that their units have to have the rotors phased?
He says “ well, if you are trying to find every last horsepower then yes you will want to phase it”
I said, “well yeah, I am”.
 WTF, why buy this stuff if you can’t even expect it to perform at a high level out of the box? We should spend $400+ on a distributor and be satisfied with non optimal performance?
 I love tuning but it makes we wonder how many rotors are out of phase out there?😡

[MrRupp]

I agree as far as the MSD stuff goes. We have a digital 6AL-2 box , with the MSD billet comp distributor. If we set the rev limiter to 6500 RPM. It will only let the engine go to maybe 6000 RPM. To shift at 6300 we have to set the limiter at 6700. They say it should be on the money, but it's not. It's kind of frustrating.
Clint

[Stangman]

Maybe silly question. Does it change timing the phased rotor when you move it or is it just moving the rotor to the proper spot. I would assume the later. I’m having almost the same thing and it might be because I’m running a lot more initial timing. Just a thought. Your making me think (how dare you)

[6667fan]

It just changes the relationship between the rotor tip and inside cap terminals. I have videos of before and after adjustments but can’t share them here. The special rotor is MSD 84211, $40-60. The top of the cap can be moved 20 degrees in either direction.
 You’ll need a second cap to sacrifice for the testing.

No apologies for stretching your brain. 🙃

[Stangman]

Ha funny about the brain. I’ve had the rotor for like 4 years I guess I’m gonna try it.

[mike7570]

I agree as far as the MSD stuff goes. We have a digital 6AL-2 box , with the MSD billet comp distributor. If we set the rev limiter to 6500 RPM. It will only let the engine go to maybe 6000 RPM. To shift at 6300 we have to set the limiter at 6700. They say it should be on the money, but it's not. It's kind of frustrating.
Clint

I was told that’s normal for the MSD to start pulling spark before the setting. It’s trying to limit it from going over and if it only started pulling at the exact setting it probably would remove a lot at once which would be real hard on the engine. I moved mine up just like you did.

[427mach1]

I agree as far as the MSD stuff goes. We have a digital 6AL-2 box , with the MSD billet comp distributor. If we set the rev limiter to 6500 RPM. It will only let the engine go to maybe 6000 RPM. To shift at 6300 we have to set the limiter at 6700. They say it should be on the money, but it's not. It's kind of frustrating.
Clint

I was told that’s normal for the MSD to start pulling spark before the setting. It’s trying to limit it from going over and if it only started pulling at the exact setting it probably would remove a lot at once which would be real hard on the engine. I moved mine up just like you did.

I found the same thing with the Ford Motorsports box, which I believe was just a repackaged MSD unit.  Had to use a chip rated a few hundred rpm higher to get it right.