[AngryInch]

Originally Posted by brad65ford

Damn, so pre face lift F90 M5's don't have lsd's in the rear? watching this video I can see that being true.

I think they're referring to LDS, a cylinder coating, anti-friction, M156 in AMG models had this as well.

You're referring to LSD, limited slip diff. Which I am not 100%, but I believe all M5s have it since they do a diff service with the break in service.

[Maverik259]

Originally Posted by MNoob

Unless the motor was pulled and put on a dyno, I would take those crank HP numbers with a huge grain of salt. Classic Dinan sales pitch. Matt does great reviews, but 9 second quarter. Cmon.

haha he did quickly resend the 9s 1/4mile once the other guy said the power to the wheels...

but yes typical low numbes from dinan to keep it "safe" but costs just as much if not more than everyone else.

[AHall]

LSD vs LDS . Those are two different things

[MuffinFlavored]

Originally Posted by pbonsalb

The Mercedes seem to be able to handle way more torque with the stock block. Maybe the E63 is the way to go for more serious power.

it is surely not. stage 1 + stage 2 e63 are terribly slower than f90 m5 with comparable fuel + mods, plus on an e63s you have to buy 3 tunes

ECU, TCU, and the something MB specific called a PTCU/CPC tune (powertrain control unit / central powertrain controller) because it limits torque

and even then, after like $6k in tunes (lol) you're still gonna get smoked by an f90 by a good 0.2-0.3s 60-130

[MuffinFlavored]

Originally Posted by AmooManiak

Would not trust my car with Carbahn. They couldn't even answer simple questions when it came to tuning, which BM3 could. I could only imagine how they "build" S63s...

yeah it's a double edged sword

you want to spend the money to upgrade to better connecting rods + rod bearings so you don't bend a rod (aka prevent problems), but trusting a 3rd party shop to disassemble and reassemble your engine is an almost surefire guaranteed way to actually cause problems lol

[MuffinFlavored]

Originally Posted by brad65ford

I wish there was more data as well, though its going to be difficult. Would suggest having the best oil / change often and not over heating (repeat runs) to keep the bearings well kept. But in the end its all about torque it seems that hurt stock rods. Eventually someone will post details of the difference if any between the F10 and f90 motors. One things for sure the motor builders aren't sharing much which is common these days. Looks like RK autowerkz has a full line of motor builds for them. Personally I'd like to be stage 2 on ethanol bend or full E85 and call it a day, not sure how long a motor would last at that power level. But I sure wouldn't put ungraded turbo on these heavy girls with out ungraded rods/pistons.

You're not going to get E85 on stock fuel system/injector from what I understand. I asked F80Paul if he's ever done a single custom E85 F90 tune on Instagram and he said no, nothing above E50.

Not only that, a great way to blow your already weak engine (compared to M177) is with a bad tank of gas, let alone a bad tank of 2 types of gas of varying quality (E85 ranges wildly at the pump, as I'm sure you know)

[MuffinFlavored]

I don't know, I have the finger on the trigger to buy an F90 coming from a W213 because I'm tired of that clunky shitty 9G MCT and the fact that despite making 680whp, the car isn't actually fast. I just don't have the balls to pull the trigger knowing it's the same (effectively) S63TU F10 motor with a few changes here and there. I blew up my S63TU stock. $80k+ dealer repair bill since they said it locked in a way that harmed the transmission + diff. Sure, they were milking it, but still.

I wouldn't even PRETEND to consider having ANY powertrain warranty with a 2018+ BMW after you press "flash" on a tune. They literally log data in the ABS module (and others) to prove your car was overboosted/driven harder than stock allows.

[MuffinFlavored]

Sorry to spam this thread, just a data point that came across my desk this week.

A friend of mine has a friend in California who bent 3 rods on his F90 M5 running a bootmod3 off-the-shelf stage 1 E30 tune. I'm sure a lot could be said that 91ACN + questionable quality E85 (no clue if the guy actually tested/measured it properly) but to blow an entire engine on a stage 1 tune?...

That's about all I need to know on whether or not this engine has been revised enough to be considered stable/strong F10 -> F90.

One tuner friend of mine said to keep the torque below 680ftlb at the wheels, and change the power curve to deliver max power at 5k RPMs. To me, I think you're still rolling the dice.

Jealous of all of those stage 2 E50 blend people getting 5.77s 60-130 though, it's a killer car that smokes the W213 when it works properly. Just sucks that it's a ticking timebomb.

[bimmerbeast7]

Originally Posted by MuffinFlavored

yeah it's a double edged sword

you want to spend the money to upgrade to better connecting rods + rod bearings so you don't bend a rod (aka prevent problems), but trusting a 3rd party shop to disassemble and reassemble your engine is an almost surefire guaranteed way to actually cause problems lol

precisely... lol

[brad65ford]

You guys don’t know about weak rods. Go look at the Audi 2.5 rs3/ttrs. My builder sees or hears about 1 a week windowing, it’s to much torque (this is the usual issue on all stock motors). Though I built my rs3 motor I probably wouldn’t do it again. I would have stayed stage 2 93.
Though High octane aggressive tunes can pushing and could destroy an engine, I would say it’s very common. The ones mentioned above do not define all conditions since we don’t know the details but I can honestly say an agree tune on shit gas will hurt a motor. Key is good tuning, logging, good fuel and knowing when to not push it. Personally I believe some people should own certain cars especially modifying them. I do not believe these are ticking time bombs, but adding bigger turbos/ meth and I think your pushing it to far for the rods.

Btw would love to read or hear about the ones mentioned, till than I do not see it as being a data point. Would be nice to see or hear it was logged prior etc instead of saying a friend of a friend etc…

I’ve actually seen first hand experience of some intense abuse on a stock motor with pure turbo / meth making 1000 hp again on stock motor (stage 3 every bolt on you can throw at it). After beating the every loving shit out of it multiple track days He sold it to my friend and he beat the piss out of it and forgot to fill up the meth, then it started smoking. They can take a lot of abuse but you need the right person taking care of it.

[Sophisticated Redneck]

The real question is, how many people bent rods running a proper octane gas? I bet most did it on 91+ 3 gallons of E85, and any that did most likely did easy to do mistake like accidentally leaving it in fith or sixth gear and low speed and since most tunes will allow full boost at 1800 rpm, that's a recipe for disaster.

I just don't understand the logic in getting a tune and not running a mix of race gas or at very least running a decent octane booster like boostane to give yourself some headroom on a 120k+ car with a minimum 20k+ engine rebuild cost. The car is BARELY ok on 91, if your running a tune you should be running at min 95AKI (not RON), mixing race gas or boostane to get there.

E85 is too variable to be trusted and plus it maxes out your fuel trims making you run lean. If you wanna play you gotta pay. Bent rods are not caused magically because 100 more HP is being pushed. It's not the HP thats doing it, its the knock.

[brad65ford]

Originally Posted by Sophisticated Redneck

The real question is, how many people bent rods running a proper octane gas? I just don't understand the logic in getting a tune and not running a mix of race gas or at very least running a decent octane booster like boostane on a 120k+ car with a minimum 20k+ rebuild cost. The car is BARELY ok on 91, if your running a tune you should be running at min 95AKI (not RON), mixing race gas or boostane to get there. E85 is too variable to be trusted and plus it maxes out your fuel trims making you run lean. If you wanna play you gotta pay. Bent rods are not caused magically because 100 more HP is being pushed.

100 percent agree. Most all issues are usually fuel related and or the person behind the wheel. People want to flash and think they are done. How I know this motor is strong is how many people running jb4 on it lol

[carseatsm5]

I don’t tune my car but like reading about the stuff. It’s cool what people can do with these cars.

Anyway only commenting to say how irritating it is I can only get 91 here in CA. I have thrown a little race gas in before but at $10/gallon it’s not likely to be a habit.

[AngryInch]

BMW needs to build engines like AMG does.

[brad65ford]

Originally Posted by AngryInch

BMW needs to build engines like AMG does.

I've had many amg's, they are good though they have their issues as well. No car is perfect.

[Sophisticated Redneck]

Originally Posted by AngryInch

BMW needs to build engines like AMG does.

Engines are fine, Its the tunning companies setting people up to fail. They remove the safeguards and headroom BMW has in place and then tell people pump gas is ok. Then all it takes is one mistake like getting some shit gas or hitting 1/2 throttle or more why your accidentally in manual mode in a high gear at low speed and boom, bent rods since tunes make it so you can hit full boost very early in the rpm band.


Bottom line: run race gas mixed to 95AKI or octane booster mixed to 95 or meth with ANY tune or save 30k for a rebuild with Carillo rods that can take knock from pump gas. I don't understand the logic on spending 20-30k so you don't have to mix race gas or octane booster but to each their own.

[brad65ford]

Will echo this, we need flex fuel sensors as well in our cars especially if we are running higher then pump fuel.

[AHall]

I will never understand this tuning thing especially on a car like the M5. If I was to tinker with a car and risk destroying it, it would be a much less expensive car I would not mind destroying. I guess everything is relative and maybe for those tuning the M5 they do not mind trashing an M5.
BMW probably has legions of engineers designing and testing these cars over years during the development phase. The tuners and their customers think they know better I guess. Then when the altered cars blow it is BMWs fault because they have weak engines.

[AngryInch]

Originally Posted by Sophisticated Redneck

Engines are fine, Its the tunning companies setting people up to fail. They remove the safeguards and headroom BMW has in place and then tell people pump gas is ok. Then all it takes is one mistake like getting some shit gas or hitting 1/2 throttle or more why your accidentally in manual mode in a high gear at low speed and boom, bent rods since tunes make it so you can hit full boost very early in the rpm band.


Bottom line: run race gas mixed to 95AKI or octane booster mixed to 95 or meth with ANY tune or save 30k for a rebuild with Carillo rods that can take knock from pump gas. I don't understand the logic on spending 20-30k so you don't have to mix race gas or octane booster but to each their own.

What are these safe guards exactly? Seems the factory tune doesn’t pour on boost till 3500rpm+.

Definitely don’t want to push the throttle too hard in a high gear at low rpm. If guys don’t know that, they shouldn’t be messing with their cars.

[brad65ford]

Originally Posted by AHall

I will never understand this tuning thing especially on a car like the M5. If I was to tinker with a car and risk destroying it, it would be a much less expensive car I would not mind destroying. I guess everything is relative and maybe for those tuning the M5 they do not mind trashing an M5.
BMW probably has legions of engineers designing and testing these cars over years during the development phase. The tuners and their customers think they know better I guess. Then when the altered cars blow it is BMWs fault because they have weak engines.

Its a drug or a disease depending how you look at it

[Sophisticated Redneck]

Originally Posted by AngryInch

What are these safe guards exactly? Seems the factory tune doesn’t pour on boost till 3500rpm+.

Definitely don’t want to push the throttle too hard in a high gear at low rpm. If guys don’t know that, they shouldn’t be messing with their cars.

It's exactly that, stock tune doesn't allow for full boost until your beyond 3k, tunes remove that and allow mich higher boost at low rpm, which is fine as long as you have the right gas and are in the right gear. However it only takes one time to accidentally leave it in manual and step on it, most dangerous would be 3/4 throttle, not enough to override manual and kick down but enough to build full boost. Like trying to pedal uphill in the top gear on a bike, something is going to break.

The second is the headroom BMW leaves being removed. Let's address the elephant in the room: How this this extra power is made? Tune companies, ALL of them, are not Gods that have figured out something BMW didn't know in their own engines to squeeze out another 100+ hp. They simply increase boost, timing, and fueling to their max, removing the buffer BMW and other car manufacturers leave for instances like when you significant other puts in 87 octane accidentally, or you in Arizona running it's crap 91 gas and it's 117 degrees out in stop and go. Yes there is skill in doing this correctly but at the end of the day, that's all any of these tunes do. They use up the headroom BMW leaves.

The real crime is then telling people it's ok to run 91 pump gas. Bottom line, nothing is free. If you tune your ride, you have to add back in a safety margin such as mixing in race gas, octane booster, meth or deal with th consequences when they come. One way or another your going to pay.

[Sophisticated Redneck]

Originally Posted by brad65ford

Its a drug or a disease depending how you look at it

Originally Posted by brad65ford

Its a drug or a disease depending how you look at it

It's an addiction and I like many here have it BAD, there is never enough, every single car or truck I have ever owned I tuned in one form or another. Sex is the only thing to me that is better, and honestly compared to my first wife, speed wins every time

With that being said, as long as you tune you ride and are smart about it, your not going to bend rods.

Here are my data points: My friends F85 is at 87k miles stage 3 tune with zero issues for past 30k miles, he runs 50/50 water/meth mix and boostane as and insurance policy.

My brother in law has a F90, stage 3 and runs a mix of race gas and 91 since he still has his cats and didn't want to use octane booster (octane booster will start to clog your cats if you use it every fill up for 10k+ miles, it takes time but it does happen). He has 41k miles and tuned it 20k miles ago.

My 173k mile, original N63 engine(the F90 engines grandfather) X5 that is tuned & JB4'd to it's limit (580hp is all you can get out of stock n63 turbos and intakes) is still going strong and I abuse it daily and it's still running low 12's, I only used boostane mixed to 96AKI. It pushes 22psi. It arguably has a rougher life then the S63TU3 in an F90. I am pushing it to the choke point of it's tiny turbos, and it weighs 5400lbs. It would be like taking an M5 and removing the forged pistons and installing 10 year old weaker designed rods and smaller turbos, then tunning it to it's limit and towing a 1000lb trailer, then beating the piss out of it every day for 80k miles. Had I not adjusted the octane, it would have destroyed itself long ago as it has been tuned for 80k of it's 173k miles.

TLDR: If you tune your ride, do it intelligently, adjust your octane accordingly and your engine will last.