Best HP ROI

[Kgolf31]

Originally Posted by Shota15

Check out their Facebook page, They have a lot of dyno results and video of vehicles they have done. I'm sure there is someone in your area that does the same type of work.

http://www.facebook.com/brentuning

Because Dynos are 100% accurate, right?

Originally Posted by jmillet

Here's how we do both car control as well as high performance driving schools.

Guess who that is in the IR Z4MC?

I love the meat and camber on those front tires

IMO, you need driver skill, OP.

If you can't lift tires, you're not going fast enough

[z4mcoupe]

Automated dual clutch transmission aka DSG in newer VW cars are very quick at shifting. It takes no effort for me to have a good launch to 60 in the R32 every single time (5.3s). In the M Coupe however, I have to be on my game to get 5s. Given the colder weather now and road condition, your encounter is exactly what I would have expected.

The only time I let the kid out of me nowadays is through exit/entrance ramps...and empty snow covered parking lots in the winter. I've found much more joy being the faster driver in my car than being in the faster car amongst other drivers.

[SmartBastard]

Originally Posted by The HACK

That is the DUMBEST measurement of "power" in cars. And while I do not condone "street racing," it's not the street racing part that's dumb.

Did you know that for two cars with a 1 second gap in 0-60 time, the difference, by the time you hit 60 for both cars, is about 1/2 of a car length? Go ahead. Do the math. That means, if say, your MZ4 Coupe is as spec'ed hits 60mph at 4.7 seconds, and the Vee-Dub hits 60mph at 5.7 seconds, by the time you BOTH hit 60 mph his front bumper will be at about your door?

All those internet talks of so-and-so "walking" his opponents by bus-length are all urban legend. No one is walking anyone else by bus-lengths. NO ONE. Walking someone else by bus-lengths is in the realm of cars with 200+ HP difference, or between a guy that has little clue on how to properly launch a car, or a guy who has no interest in staying in it.

Case in point, I once passed a Porsche 996 Turbo S in my puny Z4 3.0i by "OUT-DRAGGING" him down a straight. The HP difference between the two cars was 200+. How is that possible? I tucked into his wake as we exited the turn and I got a slight jump on him. By the end of the LONG straight he was maybe only about 1.5 car length ahead of me, which allowed me to brake extra late and take the pass on the inside (this was with some eggin' on by the chief instructor, otherwise I would have NEVER taken a pass without a point). TWO HUNDRED FREAKIN' HORSES difference.

I laugh every time I read a story about how some idiot "killed" another car by bus lengths, or someone expecting to pull car-X by said car lengths. It is clearly a sign of someone who does not know what they're talking about, has not had enough experience driving cars and drag racing. It can't be done. It doesn't happen. The only time said car beat another car by "bus length" is when car that was beat gave up.

Nice post, got this "graph" from a friend, I think he stole it from M3 forum..

[MiddleAgedAl]

Originally Posted by The HACK

Did you know that for two cars with a 1 second gap in 0-60 time, the difference, by the time you hit 60 for both cars, is about 1/2 of a car length? Go ahead. Do the math. That means, if say, your MZ4 Coupe is as spec'ed hits 60mph at 4.7 seconds, and the Vee-Dub hits 60mph at 5.7 seconds, by the time you BOTH hit 60 mph his front bumper will be at about your door?.

Perhaps I'm missing something, but I'm not sure your math is entirely sound.

See http://www.algebra.com/algebra/homew...ion.90398.html

They have 2 cars, 1 which does 0-60 in 4.2 seconds, and another which takes 5.0 seconds.
You can follow their math on the page, but the bottom line is that is that speedy car A travels 184.8 feet in the 4.2 seconds it takes him to hit 60. (assuming constant acceleration, which of course isnt' technically true unless it's all done in 1st gear)

Anyway, in that same 4.2 seconds, the slower car B travels 155.23 feet. So there is 29.5 feet between them at the 4.2 second mark.
Assuming they both continue to accelerate, and assuming car A continues to accelerate at a faster rate than B, by the time car B hits 60, that gap should be even larger than 29 feet. Hardly door handle to bumper, unless the car is 60 feet long.

Am I missing something here?

[RADRACR]

The elitism on this board gets tiresome. Whether or not your superior driving skills outperform a higher HP car is irrelevant to what OP was requesting. It *is* possible to enjoy a higher HP car around town and not crash. By elitist logic, you should sell your ///M and get a Miata or FR-S as it's "just as much fun when you know how to drive".

[Finnegan]

The conundrum here is that it sounds like you want both sound and fury for 1K. That's not really in the cards.

On the fury side, I've got to go with Beta, given the budget and no DIY: gears. It's not necessary going to make the car that much faster, but it's going to make it feel like it's got a bit more kick. That meets the fury goal, but not the sound goal. If you can find a good shop to do the install this is a good bet. Key is finding a good shop though--and it may not be the local BMW indie shop (but rather a off-road/4x4 shop that does diffs and only diffs).

Headers aren't going to add a lot of volume--they're going to sound better, and add more there, but it's not the same as throwing a Diablo, or RPI, Eisenmann, etc. on as an axle-back. Again, hits on the fury side, but probably not enough on the sound side based on what you seem to want in that dimension. Know that a job poorly done (header install, O2 relocation) will just be a bunch of problems you're not going to want, and expenses you don't want to incur.

For sound, and if you want it to sound meaner, axle-back is the way to go. And you can find a nice Diablo or RPI or similar in your budget range. Lots of sound, but not much fury. But it sure sounds faster!

I'd figure out priorities and distill down from there based on budget. Given the original target budget amount, you're going to have to pick one (sound or fury) over the other. Based on a pure hassle/risk factor assessment, I'd go with the axle-back.

[MiddleAgedAl]

Originally Posted by aestheticstorm

The elitism on this board gets tiresome. Whether or not your superior driving skills outperform a higher HP car is irrelevant to what OP was requesting. It *is* possible to enjoy a higher HP car around town and not crash. By elitist logic, you should sell your ///M and get a Miata or FR-S as it's "just as much fun when you know how to drive".

I suppose one person's "elitism" is another man's "maturity".

The OP wanted more HP. Didnt say why. It's perfectly reasonable to assume that one motivator might be that he's frustrated watching others disappear in front of him at track days. Certainly, on the street, I know of few places where that car would struggle to keep up with everyone else. I mean really, if you are pushing that kind of car hard enough where you are legitimately hitting the car's limit, and you still want more, at that point you're probably already going fast enough that I'd really hope you are not on public roads, and not because I'm concerned about you paying a big fine. (or, at the very least, please be 30+ miles out of town on a deserted road, so that a mechanical failure or lapse in concentration at 130 is less likely to take my friends and family with you).

Isn't it a helpful (and potentially cost saving) suggestion to point out how he can make the car go faster without spending thousands and affecting the car's street compliance, economy, reliability, etc? An "elitist" would probably never suggest you replace a more expensive & rare car, with a more common, cheaper car like a Miata.

[jslym777]

best return on horsepower? buy a used corvette

[3point0]

Originally Posted by SmartBastard

Nice, that's one of the most interesting graphs I've seen in a long while, thanks for posting it.

[strokeoluck]

I appreciate the info, and do think I'm leaning towards the RPI exhaust and a short shifter in spring. Maybe a trans flush...we'll see. The Vettes always intrigue me, but the several I've driven have been pretty rough around the edges.

BTW, does the term "axle-back" mean I'm just replacing the muffler...from the axle and back to the tips? Would assume so, but you know what happens when you assume.

[beta]

Actually that chart has some really bad assumptions (at least for the 4.10 gearing part), it comes from this thread.

So take the chart with a grain of salt.

Edit: Yes that's exactly what axle back means The RPIs sound really great so you'll probably enjoy it, they're also pretty loud.

I haven't installed my short shift kit, but having briefly tried out RobMs one, it's a really great mod.

[aerobod]

Originally Posted by MiddleAgedAl

Perhaps I'm missing something, but I'm not sure your math is entirely sound.

See http://www.algebra.com/algebra/homew...ion.90398.html

They have 2 cars, 1 which does 0-60 in 4.2 seconds, and another which takes 5.0 seconds.
You can follow their math on the page, but the bottom line is that is that speedy car A travels 184.8 feet in the 4.2 seconds it takes him to hit 60. (assuming constant acceleration, which of course isnt' technically true unless it's all done in 1st gear)

Anyway, in that same 4.2 seconds, the slower car B travels 155.23 feet. So there is 29.5 feet between them at the 4.2 second mark.
Assuming they both continue to accelerate, and assuming car A continues to accelerate at a faster rate than B, by the time car B hits 60, that gap should be even larger than 29 feet. Hardly door handle to bumper, unless the car is 60 feet long.

Am I missing something here?

Plenty of other factors missing here, especially the effects of traction off the line and aerodynamics, acceleration is far from linear.

[Urluz3n]

If someone sees a used set of euro headers drop me a line. PM

[zBone]

RE: That graph - how feasible is it to drop 200lbs from our cars? Lets assume I could lose 50 of that on my own :-D

[David70]

Originally Posted by aestheticstorm

The elitism on this board gets tiresome. Whether or not your superior driving skills outperform a higher HP car is irrelevant to what OP was requesting. It *is* possible to enjoy a higher HP car around town and not crash. By elitist logic, you should sell your ///M and get a Miata or FR-S as it's "just as much fun when you know how to drive".

I agree, somehow our cars have more than enough hp and asking how to make more is immature or irrelevant. I guess getting the M over the std. Z4 made sense but anymore is crazy?

[David70]

Originally Posted by aerobod

Plenty of other factors missing here, especially the effects of traction off the line and aerodynamics, acceleration is far from linear.

Take the same car (same aerodynamics), no slip (traction roughly the same), one car has more power and can go 0-60 in 4.7 seconds and the other in 5.7 seconds. Seems like the first post said you will be around half a car length (roughly 7'?) ahead and the other says you will be over 29' ahead (his 0-60 times were 4.2 vs. 5.0). If they were even close to the same results I could understand but they aren't. Which one is correct?

If I had to guess the 4.2 to 5.0 would be closer in distance than the 4.7 to 5.7 not the other way around.

[Kgolf31]

Add a LTW flywheel to that graph and you'll finally realize the differences of what those can do

[beta]

Originally Posted by zBone

RE: That graph - how feasible is it to drop 200lbs from our cars? Lets assume I could lose 50 of that on my own :-D

Very feasable, see my post here. Still waiting for someone to chime in if there's any other place to drop weight that I missed (without gutting as in this thread).

[MiddleAgedAl]

Originally Posted by David70

Take the same car (same aerodynamics), no slip (traction roughly the same), one car has more power and can go 0-60 in 4.7 seconds and the other in 5.7 seconds. Seems like the first post said you will be around half a car length (roughly 7'?) ahead and the other says you will be over 29' ahead (his 0-60 times were 4.2 vs. 5.0). If they were even close to the same results I could understand but they aren't. Which one is correct?

Things like aerodynamics, traction and such are already accounted for in the 0-60 time. It could be that the cars are the same weight, same gearing, same engine, but one is slippery, and the other is styled like a giant air brake, and that alone causes the time to drop from 5.0 to 4.2 seconds. Or maybe one has sticky tires, the other spins madly wasting power for the first 30 feet. Bottom line is things like that are factored in to the time, if you removed them the time would change.

That's why I was asking, where exactly does the half a car length idea come from ? I've basically "shown my work" as my old math teacher used to say, it's all transparent, using accepted newtonian physics formulas, you can redo it all yourself, and yet the gap is quite huge, as you say. I was hoping maybe someone observant would find some big mistake in the math to account for the difference.

Remember, that 29 feet gap is when car A hits 60; if you wait another 8/10ths of a second till car B hits 60, the gap is just over 40 feet or so. Of course the faster you go, the slower you accelerate, so maybe car A doesnt pull ahead as strongly as it did below 60, but still the gap is gonna be north of 30 feet either way.

[The HACK]

Originally Posted by aestheticstorm

The elitism on this board gets tiresome. Whether or not your superior driving skills outperform a higher HP car is irrelevant to what OP was requesting. It *is* possible to enjoy a higher HP car around town and not crash. By elitist logic, you should sell your ///M and get a Miata or FR-S as it's "just as much fun when you know how to drive".

Elitist? On a BMW forum? Noooooo!

All joking aside. My statement about someone who can't make a 300HP car go fast, adding another 100HP won't help still holds true. Once you learned to make said 300HP car go fast, then adding 100HP WILL make a difference. Otherwise it's just putting lipsticks on a pig (the ONLY thing Sarah Palin was good for, was that awesome line in the 2008 elections IMO).

The one single event that convinced me to get the MZ4 Coupe, was after that ride with the chief instructor where he egged me on to pass the 996 Turbo S on the straight, despite our 200+ HP difference, was knowing that I was wringing just about as much "speed" as I could out of the Z4 3.0i (that, and driving a convertible on track is just inherently a much larger risk), and that at that point getting a fairly familiar chassis with a 110HP boost would just mean I'm at least 100+HP faster.

On the Miata/FR-S/BRZ front, I would actually think for a vast majority of people, those ARE better equipment to start with on track than an MZ4 Coupe. They're lower HP, with superb chassis, and they're CHEAPER. Especially used Miatas. I absolutely would not hesitate to recommend to someone starting out their driving career to pick one of those up as opposed to an MZ4 Coupe, and get their feet wet in one of those before bringing their MZ4 Coupes to the track. You would actually accelerate your learning curve rapidly with those lower powered cars vs. hopping in with a 300+ HP RWD car as a completely noob, IMO.

But if the MZ4 Coupe is all you've got, and all you're ever going to bring to the track, I'm not going to sit here and tell you that a Miata will run circles around your MZ4 Coupe.

Originally Posted by MiddleAgedAl

Perhaps I'm missing something, but I'm not sure your math is entirely sound.

See http://www.algebra.com/algebra/homew...ion.90398.html

They have 2 cars, 1 which does 0-60 in 4.2 seconds, and another which takes 5.0 seconds.
You can follow their math on the page, but the bottom line is that is that speedy car A travels 184.8 feet in the 4.2 seconds it takes him to hit 60. (assuming constant acceleration, which of course isnt' technically true unless it's all done in 1st gear)

Anyway, in that same 4.2 seconds, the slower car B travels 155.23 feet. So there is 29.5 feet between them at the 4.2 second mark.
Assuming they both continue to accelerate, and assuming car A continues to accelerate at a faster rate than B, by the time car B hits 60, that gap should be even larger than 29 feet. Hardly door handle to bumper, unless the car is 60 feet long.

Am I missing something here?

Yeah, I think what's missing is that the math here assumes a constant acceleration. And we all know a car's engine is not capable of delivering that. You add gearing ratio to the mixture then all of a sudden things gets even muddier.

Take my old Subaru WRX for example. That generation WRX and STi has an interesting comparison. The WRX has 265HP and the STi 305HP, a 40 HP difference. Yet Subaru never published the 0-60 time for the WRX, because, some had speculated, that it hits 60 FASTER than the STi. Why?

The STi requires a shift to 3rd gear at 56mph, while the WRX requires a shift to 3rd at 62mph. The end result is that the two cars are neck and neck at 60mph, but if the test is measured in 0-50 the STi would enjoy a distinct advantage.

So while theoretically, the distance between the two cars should be on the orders of 30-40 ft, in a real world application the two cars are neck and nect at 60.

[Finnegan]

Originally Posted by The HACK

Elitist? On a BMW forum? Noooooo!

All joking aside. My statement about someone who can't make a 300HP car go fast, adding another 100HP won't help still holds true. Once you learned to make said 300HP car go fast, then adding 100HP WILL make a difference. Otherwise it's just putting lipsticks on a pig (the ONLY thing Sarah Palin was good for, was that awesome line in the 2008 elections IMO).

On the Miata/FR-S/BRZ front, I would actually think for a vast majority of people, those ARE better equipment to start with on track than an MZ4 Coupe. They're lower HP, with superb chassis, and they're CHEAPER. Especially used Miatas. I absolutely would not hesitate to recommend to someone starting out their driving career to pick one of those up as opposed to an MZ4 Coupe, and get their feet wet in one of those before bringing their MZ4 Coupes to the track. You would actually accelerate your learning curve rapidly with those lower powered cars vs. hopping in with a 300+ HP RWD car as a completely noob, IMO.

But if the MZ4 Coupe is all you've got, and all you're ever going to bring to the track, I'm not going to sit here and tell you that a Miata will run circles around your MZ4 Coupe.

I know we're pretty far afield from the OP's question here as far as some folks are concerned. But, FWIW, I'll second the Miata and lower HP car recommendation. Not to mention that, on a mid-90s Miata, rotors are 15 bucks a piece. Yup. 15 bucks. Engine? 2 grand or so.

Several of us MZ4 drivers, and a S/C S2K friend of mine who have gone from total noob to "semi noob" drivers were talking about how the HP really can get in the way of learning how to extract the most from a car using driving skill. We were in agreement with you, and were all kind of wishing we'd started out (in a perfect world with unlimited funds) with a nice little Miata or older non-M3 3 series.

Our consensus was that HP can lead you to think you're better/faster than you really are, but once you learn to scoot a lower powered car around quickly you're ahead of the game IMO. Why? Because speeds on the straights are totally dependent on how well you do in the corners (and out of the corners, where it's a speed multiplier). HP can make it seem like you're fast at the end of a long straight, but still, you'd be even faster if you knew how to exit the corner more quickly (multiplier).

If you've ever been left like you're standing still going into and out of a corner our ever happy little poster child Miata, you'll know that power isn't the issue. Equal drivers, the MZ4 coupe will win, but a better driver in a Miata can run circles around a lesser Z4M driver, and 100 HP more isn't going to solve that problem.

My last exhibit would be to ask the GT3 guy I passed several sessions my last track day if more power was the answer, or to ask me if more power was the answer to being passed myself by someone in, you guessed it, a Miata. Or was power what dropped 8 seconds off my buddy's times over two track days--when he'd made no changes to his car?

In a straight line, and stop light to stop light, or at the drag strip, power rules. Otherwise it's not that clear cut. What you want to do with the car, and how to go about it, as always, depends on goals and objectives. strokeoluck may not be after my improved track time goals, and may want a bit more fun taking off in first or second. Fine by me--there isn't one right direction or answer here.

[ZStig]

I'm pretty sure this guy wants to add power to go faster in a straight line, not to pass porsches on a racetrack. And there's nothing wrong with learning to do both. I personally enjoy autocross and 1/4mile drag racing equally in my car