For the love of...

[SRT8Tech]

It is actually measured at all 4 wheels and from the output speed sensor in the trans. BUT, the Speedo gets its signal from the output speed sensor in the trans through the TCM and PCM. If the rear wheels are spinning at 60mph and the car is only going 10mph the speedo will say 60mph. The trans also uses the output speed sensor for the shifting. This is why the trans will shift into 2nd gear so soon when spinning the wheels.

[Quick]

Not from the fronts. Not from the GPS (some don't have it). I believe it's taken from the drive train before the rear end? I believe it may be transmission out.

The car will engage ECS (if it's full on) if you spin the rear tires but it won't go into limp mode.
It shouldn't go into limp mode just for hitting the rev limiter either. That may not be true if you've raised the rev limiter but I think that's because of some sort of transmission limp mode (maybe that's just an AWD thing).

[Mike_Levy]

It shouldn't go into limp mode just for hitting the rev limiter either. That may not be true if you've raised the rev limiter but I think that's because of some sort of transmission limp mode (maybe that's just an AWD thing).

It does go into Limp mode by hitting the limiter. On my car it also threw a code, for the motor over revving.

[Quick]

Now that's interesting. I didn't know that. I don't suppose you experimented with it? Only in 1st? What did you have your rev limiter set at? Do you remember the code?

[Mike_Levy]

Nope didn't experiment. Only in first gear, +400 limiter, which I guess is about 6800. The code was P0219.

[johanness]

Okay, let me rephrase 'safe setting'. Can I raise my limiter to 6800 - 7000 (as prompted by the Predator) in the hopes of never hitting it with RAISED SHIFT POINTS on the Predator?

I mean, the way I'm interpreting all of this is that IF I raise my shift points on the handheld, then I have to raise my rev limits. But wait... can't do that either because it's unsafe (or at some ungodly high RPM that freaks people out and that is just characteristic of 'some' LX's from the factory). Huh?
So, I can't raise my shift points and should just accept that fact and keep things at my stock setting. Woo.

And Quick... I don't 'plan' on hitting the limiter. In fact, my question is how to AVOID it, and yet KEEP my raised shift points. It's a setting on the device... shouldn't I be able to use it and get some tech advice?

Autostick Auto upshift is ALWAYS on. I got the TSB done just for this very reason.

I guess the question is, can anyone (at Diablo, or otherwise) expand on Johan's recommendation to raise my rev limits to 6800 7000?

Johan, Mike... thank you. So I'm not going to float or blow anything by raising it to 6800-7000? Sounds SUPER high, but if you say it's a safe setting, I will gladly raise it. Our gauge read high anyways doesn't it?

I don't believe anyone said it's a safe setting.

Like Mike_Levy said, the rev limiter is a "fail safe" and you really don't want to hit it. I also think auto upshift should be left enabled. You want to set your shift points at something reasonable and your rev limiter closer to the edge of doing damage in case you somehow manage to go over the shift point.

If you plan on hitting the rev limiter then you would want to set that where you think it's going to be safe. I don't think DiabloSport has tested the limits of our valve springs. I could be wrong. I heard of one 6.1L that failed a motor at or just above 6700. It may have been due to a broken spring rather than floating the valve. I don't think you're going to get any gaurantees.

[Quick]

I guess the question is, can anyone (at Diablo, or otherwise) expand on Johan's recommendation to raise my rev limits to 6800 7000?

I can say this. Johan knows a hell of a lot about tuning and I don't.
(and I think he comes back to work tomorrow).

[johan]

Well you can, alot of people have to do just that in order to avoid the hitting the limiter issue, only way around it for now.

[johanness]

Here's an update... I STILL have this issue.

Stock/Original Backup = regular power, no hesitation at WOT.
Canned tunes (91CAI/93CAI) = both hesitate at WOT with or without raised shiftpoints and having raised rev limits to the sky.

I can only assume this is a tuning issue and I'll need to log some data and submit for some tweaking? That is, unless someone can recommend a CMR tuner that is more local to Vancouver, BC than Northern California. (the 'locate a tuner' section is useless for our area. Dealers, no dynos)
Any help is appreciated.

[johanness]

So I guess I'm knocking into next week and the engine's pulling timing like a SOB? Anyone?

[Mike_Levy]

Have you logged it? Thats the only way to know for sure.