Successful Gen IV Tuning with Torrie McPhail and HPTuner

[99RT10]

Its not an issue of what we can increase the actual rev limit to, its more to the point of what should we allow it to be safely. Yes I can set it to 7200 but I don't think its feasible or smart to run it up that high unless you have a purpose built motor for that.

By expanding the power band to say 7000, it will make this car an unbeatable combination. I would love to see someone push the envelope a little. I wonder where the power would start to drop off. I am betting past 7200.

[Black Moon]

Do the Gen IV's oil any better than the gen 3's? If not 6500 could be a grenade in the making. I'd be curious if the peak of your HP/ torque curves move higher (more rpms) with the tuning. If not what are you really accomplishing by the RPM change. Very interested in your results. Glad someone is taking the time to make this work.

[tmcphail]

Graph is below. From what I have witnessed things start to flatten out above 6250. I don't really think taking it to 7K will be ultimately beneficial on a stock motor.

[Black Moon]

The Gen 3's drop off at 5800. What do the Gen IV's drop off at? I would never run a stock motor that high. Their oiling design is just not adequate. You are talking modified motors right?

By expanding the power band to say 7000, it will make this car an unbeatable combination. I would love to see someone push the envelope a little. I wonder where the power would start to drop off. I am betting past 7200.

[Steve M]

Do the Gen IV's oil any better than the gen 3's? If not 6500 could be a grenade in the making. I'd be curious if the peak of your HP/ torque curves move higher (more rpms) with the tuning. If not what are you really accomplishing by the RPM change. Very interested in your results. Glad someone is taking the time to make this work.

The Mopar PCM rev limit is set to 6,500 (up 100 from the factory rev limit) - I'm guessing this is a safe limit for the car, otherwise the Mopar folks would have left it alone.

Beyond that is anyone's guess though.

[Black Moon]

That's up from the 3's. I think they were 6250 or 6150. I dropped mine to 6000. The car gains nothing past 5800 even with a Paxton so why push it was always my philosophy. Both my tuners agreed.

The Mopar PCM rev limit is set to 6,500 (up 100 from the factory rev limit) - I'm guessing this is a safe limit for the car, otherwise the Mopar folks would have left it alone.

Beyond that is anyone's guess though.

[FrgMstr]

I think it is worth mentioning here that "canned tunes" are not going to be the thing....yet. While Torrie was trying to get my throttle response more crisp, he did note that my 2008 responded totally different to tuning inputs than his 2010 did. Of course we know the 08 had worse throttle lag than than 09 or 10. But so few tunes have been done at this point that a one size fits all approach is likely to not be around for a while.

[Revolution]

By expanding the power band to say 7000, it will make this car an unbeatable combination. I would love to see someone push the envelope a little. I wonder where the power would start to drop off. I am betting past 7200.

I would bet you will be picking up motor parts before you get to 7200rpm

[Black Moon]

Especially number 3 and 4 pistons and rods.

[Steve M]

That's up from the 3's. I think they were 6250 or 6150. I dropped mine to 6000. The car gains nothing past 5800 even with a Paxton so why push it was always my philosophy. Both my tuners agreed.

It really depends on the type of driving you are doing too - on a road course, there is usually no need to tap the rev limiter on every shift, unless you like rebuilding motors. For drag racing though, it isn't so much about how much (or little) you gain beyond a certain RPM point, it is about where you fall back in the power band after the shift. I heard the same argument from the LSx guys back when I was drag racing my Camaro..."it doesn't gain anything past 5,800 RPMs, so I shift right at 5,800 RPMs." The guy that said that couldn't figure out why I was trapping 2 MPH faster than him all day long, both cars bone stock...I shifted as close to 6,200 RPMs as I could.

More RPMs = more wear and tear though, so there's no free lunch.

[Black Moon]

I agree that canned tunes may be ok for a daily driver but they are usually so generic and conservative that there is a ton of potential left out there. I worked with Todd at A&C. He did a great job explaining each separate issue of the tuning process. I also eliminated the Split Second box for tuning and just used SCT.

I think it is worth mentioning here that "canned tunes" are not going to be the thing....yet. While Torrie was trying to get my throttle response more crisp, he did note that my 2008 responded totally different to tuning inputs than his 2010 did. Of course we know the 08 had worse throttle lag than than 09 or 10. But so few tunes have been done at this point that a one size fits all approach is likely to not be around for a while.

[Murpowa]

I just got an appointment set today at 4:30 to get a few dyno pulls in over at True Street here in North Texas. w00t!!1

Can't wait for the results!

[Revolution]

Is it 4:30 yet haha

[slpfirehawk]

Now it is! P.S. Revolution I sent you PM... Let me know. Thanks!

[FLATOUT]

Now it is! P.S. Revolution I sent you PM... Let me know. Thanks!

Texas is central time

[slpfirehawk]

Dang it! Thanks for heads up. Got too excited

[Nine Ball]

That's up from the 3's. I think they were 6250 or 6150. I dropped mine to 6000. The car gains nothing past 5800 even with a Paxton so why push it was always my philosophy. Both my tuners agreed.

This defies performance logic. Your Paxton car will be faster, if you shift it at 6200. Centri blower needs rpm, to make more boost / power. I shift my Paxton / built engine at 6400. It is still pulling HARD at that rpm. Plus, when you shift at higher rpm, the next gear starts at a higher rpm.

[99RT10]

I would bet you will be picking up motor parts before you get to 7200rpm

With the Gen 5's being all forged, you don't think they would last to 7000 RPM?

[FrgMstr]

Well, I hate to disappoint, but it seems after all the racing I have done lately, the clutch decided to give up the ghost on our first run. I couple of good logging runs in to share with Torrie though but the clutch was slipping.

Stock clutch with 31K miles on it that has suffered through many dig races, roll races, and standing mile runs. Time to call JonB.

[Steve M]

With the Gen 5's being all forged, you don't think they would last to 7000 RPM?

I'm guessing valve train stability would be more of an issue than whether or not you have forged pistons.

[Viper Girl]

I want to Welcome Torrie as a VOA sponsor... Support your Sponsors guys!

Thanks Torrie

[Revolution]

Sucks to hear that

[Revolution]

With the Gen 5's being all forged, you don't think they would last to 7000 RPM?

Try it I guess and find out
My money is on it won't

[01sapphirebob]

Well, I hate to disappoint, but it seems after all the racing I have done lately, the clutch decided to give up the ghost on our first run. I couple of good logging runs in to share with Torrie though but the clutch was slipping.

Stock clutch with 31K miles on it that has suffered through many dig races, roll races, and standing mile runs. Time to call JonB.

#ClutchFail

Damn..that sucks. Hopefully Jon gets you up and running soon. I expected this thread to explode when you posted.

[FLATOUT]

LMAO, dude that sucks but I can't help but laugh as we have been through so many little setbacks with these cars. I blame it on the new power the car is making . All good dude you'll get the new one in and out the numbers up.

Andy