How much power is too much?!

Discuss general engine, turbo and supercharger conversions in this section

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Jhonno
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Post Thu Jun 01, 2006 10:25 pm

Thought this would be the right place to put it, after all all the high powered e30's hang around here..

How much power is too much? Ie when does it start to overwhelm the e30 chassis and it begin to lose its balance and chuckability?

Just been thinking about it since reading something someone posted on another forum..
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Turbo-Brown
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Post Thu Jun 01, 2006 10:36 pm

Good question, had the same thought after seeing a vid of a go-kart powered by some motorbike engine which just wouldn't go in a straight line!

For my money, it's not necessarily the amount of power that makes a car uncontrollable, but how progressively the driver can apply that power.

I reckon that with a progressive throttle linkage and some practice, no amount of power would be too much. Afterall, you're making next to bugger all power at low revs/ small throttle openings so if you can keep the throttle openings small for the first half of the pedal movement say, and ramp the rate of opening up thereafter, avoiding binning it at every bend shouldn't be too much of a problem.
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Jhonno
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Post Thu Jun 01, 2006 10:51 pm

i see what your saying.. its more about throttle control rather than power
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Andy335Touring
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Post Thu Jun 01, 2006 11:07 pm

If it's a turbo engine with bad power delivery and poor tyres then it could be fairly low, may be as low as 250bhp ?

A well sorted turbo set up should be a lot higher, with modern stand alone ECUs you can map/control how the boost builds up through the rev range i think ?

I'd guess for a N/A engine you could say the same thing, it depends on the power delivery ?

Suspension/tyres also have a big contribution to make, if you could some how graft on the rear suspension and trick LSD from say an E46 M3 and fit a decent width tyre then that would make handling/transmiting big power so much easier !

Some thing to ponder.......

1st scenario

Big iron block N/A V8 lowish reving engine making 330bhp @ 5.5k rpm and 360lbs @ 4k rpm with fairly short gearing

2nd scenario

Big alloy block N/A V8 free reving making 400bhp @ 6.8k rpm and 360lbs @ 4.4k rpm with longish gearing
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Post Thu Jun 01, 2006 11:20 pm

9psi @ 4k all in one huge surge of power causes wheelspin in 3rd and 4th, even 5th in the wet :D I don't need roundabouts to get sideways anymore :D
Do miss the linear power of N/a I used to have but I'd never go back now!
There are provisions to set rpm/boost limits when I fit the solonoid but for now it's just raw aggressive clutch straining power!
And you can never have too much power :twisted:
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Jhonno
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Post Thu Jun 01, 2006 11:23 pm

good point. Scenario 1 is gonna be more of a handful.

i guess its not an easy thing to quantify, depends on the power delivery, chassis setup..
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Kos
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Post Fri Jun 02, 2006 10:52 am

i've looking in to this aswell with my car.

i've decided to stay around the 400hp figuer, just for the fact any more power will put a strain on the drive components of the car, and realisticly will you be able to enjoy it?? you can have a car that is too quick and powerfull to use. and with the last e30'sboing about fifteen years old now, how much can the shell's and chassis take?? looking at my M3 the other day, the way its been driven, the power and torque has contributed to the damage.
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Post Fri Jun 02, 2006 6:34 pm

what about traction/launch control, £600 from racelogic if you already got ABS.
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Post Fri Jun 02, 2006 7:01 pm

has anyone done a 4wd coversion on their e30? i was quoted around £2500 to fit full cosworth 4wd system,but knowing garages it would probably end up nearer double that by the end.how about the 325ix 4wd system,is that still available? i know i have traction problems and ive 'only' got 290 bhp at the moment winkeye
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Post Fri Jun 02, 2006 7:12 pm

They did IX's in europe but I dont think its very strong for alot of power without mods to front diff or something, best ask Ixer about that tho he knows all about the weak spot on IX transmission
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Post Fri Jun 02, 2006 7:23 pm

weak spot on IX transmission
indeed, they struggle with the std output :lol:

You can honestly never have enough power, but the chassis can :wink:
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Post Fri Jun 02, 2006 7:24 pm

It's not so much how much power you can squeeze from an engine, it's if its usable power, a poorly mapped turbocharged or n/a engine won't deliver the power in a usable fashion unless the gearing is set up to uterlize the delivery

IE: High rev, high power engine (nothing under 4k for instance) would need a short ratio box, torquey engine would need longer ratios.

Originally turbo's were laggy as hell but with modern mapping and ECUs (as mentioned before) It's possible to map a turbo much like a N/A engine with usable power and torque.

It's about the balance, going to one extreme makes it harder (and more expensive) to set the car up to take it.
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