? about Tunes, and raised rpm redline

[Killerfish2012]

Originally Posted by FormulaMMM

Killerfish, I'd personally like the extra 200 rpm for track use. Especially with dct. Doubt it will make it much quicker, but the little bit of added flexibility would be nice. I don't like the idea of revving much beyond 8600 though...

Hey brother, how's it going? Yes, I'm getting the tune with the extended rpm redline. Yandy's had it, and from watching his videos, you can see the slight extra little pep he's got in the straights. I'm all paid out for 4 events so far. Hope to see you out there.

[DKX4///M]

Correct me if I'm wrong, but doesn't the M3 GTS redline at 8600rpm?

[e46e92love]

Max power is not at 8250 as stated earlier. It's at 8300 according to BMW, so I see the advantage of a slightly higher rpm is allowing to not have to shift perfectly to get max power (especially if driving a manual).

That being said, every 500 rpms when you are talking 7500+ is a big deal from an engineering perspective and need for stronger internals. So 8400 to 8600 is not a none event. I assume less so because it's not making more power as opposed to tuning to make more power with the 200rpm. So your engine prob won't blow up the day after you do it, but always remember you have to "pay to play"

Kawasaki can speak to this probably better than anyone on here.

Cheers,
e46e92

[e46e92love]

Originally Posted by regular guy

Very little difference with FBO DCT.

I'm actually surprised there is any difference.....learn something new every day

Cheers,
e46e92

[kawasaki00]

Originally Posted by e46e92love

Max power is not at 8250 as stated earlier. It's at 8300 according to BMW, so I see the advantage of a slightly higher rpm is allowing to not have to shift perfectly to get max power (especially if driving a manual).

That being said, every 500 rpms when you are talking 7500+ is a big deal from an engineering perspective and need for stronger internals. So 8400 to 8600 is not a none event. I assume less so because it's not making more power as opposed to tuning to make more power with the 200rpm. So your engine prob won't blow up the day after you do it, but always remember you have to "pay to play"

Kawasaki can speak to this probably better than anyone on here.

Cheers,
e46e92

This is true, not only is it just a rotating assembly that spins faster it then fires more times per second. Parts stress goes up at a exponential level relative to rpm. You start getting into limit speed for valve springs etc, it can get very involved. In short I see it this way, the DCT car with the higher rev limiter really just turns the same rpm as a 6mt car stock.
Here is a good example, we had a engine that turns 10k easy and all day, driver went from 3rd back to 2nd on upshift, data log showed 11200 for about 2 seconds. Upon teardown the rod bolts broke stretched to the point of the heads popped off, the rod caps came off and it was a total loss. There was a certain component that was hit by the piston in a cylinder that did not come apart. (Cant really say) but we modeled it back out and the piston actually rotated 25 degrees in the bore. Incredible forces to do that...and that was just a extra 1200rpm for 2 seconds.
I know that is a totally different scenario but just thought I would share.

[e46e92love]

For those that care I'm in the beginning stages of putting together a project for a 8800 redline making power to 86/87. You can imagine the work to improve top and bottoms ends from a strength perspective.

Cheers,
e46e92

[FormulaMMM]

Originally Posted by Killerfish2012

Hey brother, how's it going? Yes, I'm getting the tune with the extended rpm redline. Yandy's had it, and from watching his videos, you can see the slight extra little pep he's got in the straights. I'm all paid out for 4 events so far. Hope to see you out there.

Same to you dude. Give me some feedback asap on the raised limiter!

[alexvegas65b40]

Originally Posted by EJT86

I went with a tune that tops at 8300. Mostly for engine safety plus I don't need an extra few miles added to my top speed THAT badly. If you notice your tach says the engines top speed is 8250 redline is perfectly between 8000 and 8500 so going to 8300 is still a slight raise

The stock engine revs to 8,500 rpm (hard limiter) soft limiter 8,400 rpm

[alexvegas65b40]

Originally Posted by Ezio

i would rock the 8600RPM redline. There is no way BMW is going to max out the engine from factory. the engine should be able to handle 8500RPM no problem.

Exactly, bmw tested the s65 and s85 to 10,000 rpm, that being said it does not mean the engine can normally rev that high and still make some power, raising the limiter 100-200 rpm makes no difference in terms of reliability imo.

[SYT_Shadow]

This is an old topic, but I have the limiter set at 8500rpm (100 more than stock).

Per Steve Dinan, who as the developer of the P65 engine may just know something more about these engines than Joe Six Pack, over 8500rpm you may have hydraulic lifter failure

[Redd]

You're running out of air in the higher rpms anyway with stock headers/cams. 8600 would only really be a small advantage in 1st and 2nd.

[pbonsalb]

Car pulls hard to 8600 in 1st, 2nd, 3rd and 4th. Have not quite gotten there in 5th yet.