Ok there's a lot to unpack here. Firstly I want to say I thought you were talking about purely ICE output, if you're referring to ICE + Hybrid Drive output, then sure you're probably easily be making 320hp at the crank easily (though probably not 370). If it's ICE only then it's doubtful if you have no additional modifications (the stock catalytic converter and OPF if you have it are quite restrictive).
You won't be able to tell without a dyno if what you care about is the actual BHP/WHP. This is ultimately a stupid game to play as which dyno, conditions, how it accounts of drivetrain losses to back out the crank horsepower. HP/Dyno charts between individuals are never comparable, they should be viewed as tools to help you tune/setup YOUR car in YOUR specific application, not as something that's comparable between individuals thousands of miles away from one another under different conditions. Dyno charts ... even from SAME dyno manufacturer ... are not SAT scores .... it's more like comparing your grades in english class (comparing within your class with the same teacher is "ok" but comparing between schools or districts is questionable).
If what you actually care about is how fast it is in the real world, dragy or actual dragstrip numbers from the same day/place are comparable and if you want to look at it from a more engine centric perspective what really matters is the entire shape of the power curve with a focus on the part of the curve you'll use ...i.e if shifting at 7000rpm redline drops you to 5000 rpm in the next gear, and you're an absolute driving god, really only the 5000-7000rpm "matter" .... assuming the power curve didn't fall off the side of a cliff .... which CAN happen
Ultimately what you "feel" are G-forces.
None of the stuff above are surprises to you but I think it's just important to reiterate the importance of the real world info/measurements
over "random math and figures provided on the internet".... Even if you get on a dyno and it shows you're putting down *calculated* 380 brake horsepower .... does it matter if the guy next to you who only puts down 300 BHP is 0.2s faster in the 1/4 mile ?
Now for the thinking/logic which you've kinda missed on (to be fair, you're in the same boat as 95% of people on the forums/internet who do this, but you have the right attitude)
Firstly, take the BM3/MHD numbers with a grain of salt. In the real world things don't work like they do in a simulation or a model. Your car can respond tremendously well to a tune and your friend's car which is otherwise identical might not. It's important to know that the figures that BM3 provides are at best an average expectation and at worst extremely cherry picked figures. Also, is the % increase quoted the % increase at a given RPM associated with peak power in run 1 or run 2 ? is it the percentage increase of peak power ? is it the maximum percentage increase of power at ANY part of the curve ?
My 520i which has the B48B20B motor (mechanically identical to the 30i) struggles to make more than 300bhp on a random all wheel dyno ... I have 98RON fuel and I experience pretty severe timing retardation on full throttle, even a full can of Torco octane booster still results in intermittent timing retardation. Should I be upset at BM3 for this ? Maybe when stock my motor wasn't putting out the 184hp claimed. Ultimately what do I care more about ? The number on a graph ... or maximizing what I can do with my platform (for performance/reliability) as it exists sitting in my garage ? If you chase after numbers on a screen, two things will happen... 1) you WILL manage to achieve that number because these things are easily manipulated and 2) you'll lose sight of having fun with the thing because you will probably end up making dumb decisions which prioritize the number on the screen as opposed to something more real like reliability, turbo lag, etc.
Secondly, you also need to understand that electric motors also have a power curve just like the ICE motor. Yes electric motors tend to have a very flat power curve (relatively speaking) but it isn't a constant output. It would be VERY "handwavy" to simply just add the max power output of the electric motor to your peak power on the ICE and say combined power = A+B. The real world just doesn't work this way. To be fair to you, you WERE conservative in your estimate by taking 60 something (~50% peak electric power) + estimated ICE BHP but there's the underlying assumption that the electric motor is actually helping when the engine is operating in it's max load, max throttle/boost, high rpm state (which isn't neccesarily a reasonable assumption for lite-hybrids)
Thirdly, just forget about "adding torques". While it's actually "ok" to do in this instance because the electric motor is placed before the gearing in the transmission (taking the place of the torque converter), in most scenarios of hybrid drive the motors are situated after gearing which makes the concept of "adding torques"
completely retarded. On top of all this, torque as a "performance paramater" also means basically nothing, all you care about is the shape of the power curve, torque at the engine is multipled by gearing. Saying an engine make 300ft-lbs of torque at the engine is quite useless because what matters is WHERE you're making the torque, 300ft-lbs of torque at 1000 rpm is extremely impressive (.... because that's the equivalent of 1500hp) whereas 300ft-lbs of torque at 5000rpm is a "meh" 290hp.
Fourth, I'm nitpicking here as you're actually doing well by comparing with the 540i conceptually but you're also making a LOT of hand wavy assumptions.
*weight: no one knows the weight of literally any car, there's massive variance between individual examples and manufacturer quoted weights often times are inconsistent even with themselves, ultimately you don't know the weight of your car unless you put it on some scales, how much does my G30 520i weigh ? i've seen numbers as low as 1500 kg and some as high as 1800 kg depending on the source... I have literally zero idea.
*power/weight: you're relying on a figure of questionable accuracy (weight) to predict/extrapolate an unknown quantity (power) based on your realized acceleration figures compared to some numbers you found online presumably (absolutely inapproriate to be doing this) AND you're using the worst acceleration metric (0-60mph) as it's literally the MOST manipulated number both in terms of how it's calculated (with or without rollout) as well as it's succeptibility to conditions (prep'd surface ? launch control ? brake boosting ? etc.)
Quote:
Originally Posted by Slo G30
I know you have a lot of experience in this area, but are you sure it can't be making around 320 at least?
That estimate I provided was based on BMW's official numbers on the car (which I believe are underrated) as well as Bootmod3's official tune percent increase numbers.
From Bootmod3's website:
20i models:
Stage 1 91 octane: up to 42% HP / 46% TQ
Stage 1 93 octane: up to 46% HP / 48% TQ
Stage 1 E30 octane: up to 53 % HP / 50% TQ
Stage 2 91 octane: up to 50% HP / 48% TQ
Stage 2 93 octane: up to 54% HP / 50% TQ
Stage 2 E30 octane: up to 60% HP / 55% TQ
30i models:
Stage 1 91 octane: up to 14% HP / 26% TQ
Stage 1 93 octane: up to 16% HP / 26% TQ
Stage 1 E30 octane: up to 20% HP / 28% TQ
Stage 2 91 octane: up to 16% HP / 28% TQ
Stage 2 93 octane: up to 18% HP / 28% TQ
Stage 2 E30 octane: up to 22% HP / 30% TQ
What was going through my mind was that stock...the b46 (basically a 20i engine) makes 184hp...so on a stage 1 tune, the b46 alone should be making approximately 184(1.46) = 268HP (I run the car on 93 all the time).
From there, the electric motor is supposed to make 111hp and 184lb-ft of torque, and from my experience flooring it.....the car only will apply all 111hp if its in a specific gear locked in for a considerable amount of time...otherwise it will only supply around 64hp (Calculated by taking BMW's net HP amount for the car and subtracting it from the stock b46 number(248 - 184 = 64)).
So I added 268 + 64 to get 332 at the minimum (or maximum if my claims about the electric motor are false)
And then I added 268+111 to get a....quite unreasonable 379HP as a maximum.
I calculated the torque the same way, and I came up with like 214(1.48) = 316+ (310lb-ft stock net torque - 214lb-ft stock engine net torque = 96) = 412lb-ft of torque as a min net torque, and then once again that maximum torque value of 316+184 = 500...(that seems impossible though)
I originally accepted the fact that my car was making around 350HP and 420lb-ft of torque though since my car managed to hit 0-60 in 4.78 seconds, which is around the same time as a stock 540i which has more power, but carries a lot less weight (3847lbs vs 4550lbs) (I managed to do a better-timed run compared to the previous run I posted above).
I also believed around 350 might not be impossible when I saw another 530e on a stage 2 tune making 399HP and almost 450lb-ft of torque
http://www.facebook.com/mgflasher/po...9804602623732/
Attachment 3232272
And there are lots of other owners that have done either stage 1 or stage 2 tunes that are all pulling above 320HP easily. I'm pretty sure you know this...but the 530e compared to the 330e has a electric motor with a larger output, so that might be the extra 20-30HP that we are missing.
Again, you have more experience with this stuff, so please advise. (I'm only 19 and willing to learn)
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