[MINIgarage]

Hey everyone, I have a customer who is buying a Cooper CVT; he wants more power out of it, but can't go to a Cooper S because his wife can't drive a manual. He tells me that a local tuner can get in a Hartge kit that will give him 200 bhp, but the only Hartge kit I know of is for the Cooper S; and I'm a little skeptical of running 200bhp through a CVT designed for 115bhp. If anyone can help, it would be greatly appreciated!

[nfo]

funny story!
good luck getting much much more bhp than stock with a CVT, hartge 200bhp kit is for S only!

[nonsequitur]

This configuration offers significant opportunities for power; best thought about as "percentage improvements" starting from 115bhp and 110# torque. The CVT will accept more power; how much is a question we're still working on.

12/18/2003 Edit: I now believe this statement above to be incorrect based on new MINI and ZF Group information. The MINI CVT-equipped cars have been calibrated to accept 150Nm torque (110 ft-lb), which is the standard output of the Cooper.

I've done some limited investigations, but have not made any changes until we better understand how the CVT truly works.

What's fun about this power side of the equation is that big percentage changes should be possible relatively inexpensively.

There are several people doing headers. I've seen one (MINI-Madness) being independently tested, and the testor was surprised to see "significantly more than" 10hp gain. That's at least 9%!

A very free-flow Cat-back exhaust will augment this gain.

On the other side of the motor would be very-careful cold air induction.

Someone told me that once we get going, a reasonable, affordable target should be 130-135bhp. That's something like 17% more power, combined with the more balanced Cooper CVT, that should become a very entertaining machine at track days with the MC 5-speed and MCS 6-speed guys.

[nonsequitur]

Someone in another thread said today that they were trying to "find 35bhp" for the Cooper CVT. They approached the math by subtracted the stock 115bhp from the CVT-rated 150bhp = 35. I like this concept and thought process.

What components are the most effective way to do this 35bhp?

[punkeyfunky]

Quote: Originally Posted by nonsequitur

Someone in another thread said today that they were trying to "find 35bhp" for the Cooper CVT. They approached the math by subtracted the stock 115bhp from the CVT-rated 150bhp = 35. I like this concept and thought process.

What components are the most effective way to do this 35bhp?

I'm the guy that wants to 'find' the 35bhp.

Whilst I want more grunt, I don't want to go too far yet; that is, I know that I can get away with certain mods, but I don't want to upset my dealer too much as I'd rather keep the TLC/warranty in tact.

I'll be looking at making my MC CVT breathe better, that is more air in, and more air out (induction kit and cat back exhaust). After hearing good things here on MINI2 I'll most likely got for the Pipercross induction kit and a PlayMINI exhaust (UK based, but I'm sure they'll ship to the USA - www.playmini2.co.uk). More in = More out (most of the time!)

I suspect that with more air coming in on the induction side, the ECU will notice the mixture getting weaker, and simply pump in more gas. This should work to a point, and I don't think I'll need to go over and above what the factory ECU fuel map provides - time will tell.

I might well change the wires to help improve the HT side, as well as some other plugs (I'd favour HKS, if they do a plug in the appropriate range, S35i's might be too cold)

I'm not really a huge fan of ECU remaps; the cost involved for such a small power increase is excessive. My Supra's running at 350+bhp on the standard ECU map.
Many manufacturers (say, Ford) use one basic lump to power an entire range of cars; as such, the ECU maps are flexible and allow for tuning/detuning as required. The MINI's engine only really powers the One and the Cooper (forget the MCS in this context, as it's not normally aspirated). So, I'd argue that the standard Cooper ECU map will be already at the best settings, and an aftermarket remap may well detune the engine. I'll only start looking at ECU remapping when I can do it myself, with the laptop in the passenger seat.

I think thats about as far as I can go before I upset the dealer.

Other things I've considered, that are either more pricey or a warranty-voider are:
- gas flow the head, smooth out the insides for better breathing
- lighten the bottom end
- mess about with different cam profiles
- buy a full 'race' system, with sports CAT (gotta meet those emissions regs)
- start losing weight anywhere and everywhere (esp. unsprung mass)

Of course, the CVT is controlled by electronics somewhere - that's something I'd like to play with.

In the long run, I think that the induction kit & exhaust will provide the best 'bang for the buck'. I'm not going to worry about wringing every last ounce of power out of my car as I still want it to be reliable, used for commuting etc. Of course, as power increases, the engine's longevity decreases. Conversely, less power = more life; look at classic VW bugs - low power, low stress engines that go forever.

The only way to do a "real" test on any power gain is to do a dyno run before and after the mods. No idea where I can get the car dyno'd, so that might not happen.
I'll just have to go on feelings/impressions (and stay subjective to avoid the placebo effect) and maybe try and outdrag another standard MC CVT.

I know I've made lots of generalisations and assumptions, so others thoughts are invited

Lee

[punkeyfunky]

So... I just ordered the PlayMINI exhaust and a Pipercross induction kit is on back order. Sorted.

Lee

[nonsequitur]

Cool. That means we will get reports along the way on what you find out. Others will have other favorite setups to report on.

It should be possible to find a dynometer in large metro areas. I was surprised here when we looked. It's not cheap typically, but there are car clubs doing "dyno days" and such where you might be able to come along.

I like the title of this thread which searches real specifically.

[punkeyfunky]

Quote: Originally Posted by nonsequitur

Cool. That means we will get reports along the way on what you find out. Others will have other favorite setups to report on.

It should be possible to find a dynometer in large metro areas. I was surprised here when we looked. It's not cheap typically, but there are car clubs doing "dyno days" and such where you might be able to come along.

I like the title of this thread which searches real specifically.

Well, the PlayMINI cat back system is now installed. It sounds lovely

I only fitted it (well, had it fitted) on Saturday, and then left the country on Sunday (work, unfortunately), so I can't really say whether there is any more power there.

I'll keep my eyes peels for a dyno near me, and if the chance crops up, I'll use it.

Watch this space [thread...]

[Electrc109]

Quote: Originally Posted by MINIgarage

Hey everyone, I have a customer who is buying a Cooper CVT; he wants more power out of it, but can't go to a Cooper S because his wife can't drive a manual. He tells me that a local tuner can get in a Hartge kit that will give him 200 bhp, but the only Hartge kit I know of is for the Cooper S; and I'm a little skeptical of running 200bhp through a CVT designed for 115bhp. If anyone can help, it would be greatly appreciated!

no need to be skeptical, the manufacturer of the CVT actually say this tranny is rated up to 200bhp!!!

IMHO the Cooper Works Kit provides the most real world tuning out there. An improved power band provides more powerful driving than merely a peakier power band. Is the Works Kit available with a CVT???

[nonsequitur]

Be careful. I don't think that ZF rates the ecoTronic VT1F (the CVT in our cars) at more than150bhp. That gives us an illusive but exciting 35bhp to seek out from the best of the tuners!

The CVT will magnify any of this gain because it "uses" the available torque more effectively so long as it is mapped to an appropriate narrow band.

[Spookyfish]

Transmissions are usually rated for torque and not horsepower. Horsepower is a product of torque and rpm's.

The CVT in de MINI can handle 165Nm (of ~ 121lb/ft) according to ZF's website. So we have 15Nm headroom.

[Spookyfish]

And that's not alot might I add...

Also, this month's EVO mag said: don't bother tuning a Cooper, the gains are minimal.

So *if* you want to speed up your Cooper, you can make sure as little power as possible is lost: use the 15" rims, toss out the back seat and join the gym. I'm not sure if a lighter flywheel fits in this list.

[nonsequitur]

I should have caught the "torque" angle here. BHP is a math conversion of torque. Sorry ..., and thanks to spookyfish for getting it right and documenting the numbers. The gym and wheels comments are also correct.

We've got a "momentum car" here, lot's of "performance" in the driving envelope but a low powered vehicle that needs good technique to drive quickly.

15Nm is a nearly 14 percent (%) increase on 110Nm. That's actually a big gain, I think. It would definitely be noticed.

The Cooper and One aren't rocket ships, weren't designed to be, but they sure move through the territory quickly, even very quickly, and with poise and balance and grace!

[Electrc109]

So, is this unrelated?

"The transmission control unit takes due account of vehicle and engine data, as well as variable data relating to the prevailing roadspeed, accelerator position, and acceleration. From these data, the ZF-Ecotronic computes the control commands for engine and transmission which enable the full potential of engine power to be delivered in any phase of operation. The system is also autodidactic and is able to adapt its approach to shift management to suit the driving style of any given driver.
The ZF-Ecotronic can be supplied for cars with longitudinal or transverse engines rated up to 140 kW (200 bhp), and for either FWD or RWD models." From the ZF Group Web Site

[nonsequitur]

No, the description is related but there are several ZF ecoTronic CVTs with different specifications. The CFT30 can handle 310Nm, the CFT23 is 250Nm, and the VT1 is 165Nm.

Also, the VT1 uses 6-disk oil-bath clutch packs (1-Forward, 1-Reverse) to transmit power from engine to transmission, which have a different power tolerance.

This is an area where we're looking for much more information.

[Electrc109]

Okay, I realize that the VT1 can handle 165Nm of Torque. But torque is twisting power, I am concerned about pulling power, which is Horsepower. I guess I need to ask someone how much torque I get from an 85 shot of nitrous...

[n3nyongmini]

Has anyone heard/seen/trailed a chipped CVT?

Seems like that might be the best, solid "bang-for-the-buck"...

I see TonyB2's (?) post in the "technique" thread, but I'd be interested to hear about any digitally-modifeid CVT's in the US.

Powerchip advertises a 13hp & 11 lb. ft gain with thier installation, which rates at just under $38/hp gain; admittedly, I don't know where they're measuring the hp... Maybe $44.54/lb. ft. is more applicable.

That's almost half way to 35hp. Maybe its me, but I'd trust a digital mod over an intake/exhaust mod - and depending on the specific intake/exhaust equipment, it might be more cost-effective.

Here's the info they put out:

http://www.powerchipgroup.com/produc...2003&make=Mini

[nonsequitur]

Power, no matter how you want to measure it, is a function of air volume through the motor. More air, more power - which is why so much attention is given to intake (and getting denser cool air that expands to "more" air), exhaust to get it outa there, and various chargers (super, turbo, both) to pack it into the motor.

Every change or adjustment is a compromise that effects some items positively (for the particular purpose) and others negitively (from some viewpoint).

The electronics are a HUGE part of today's engines, but like everything else, you're buying a compromise not just more power.

[punkeyfunky]

Quote: Originally Posted by n3nyongmini

Has anyone heard/seen/trailed a chipped CVT?

Seems like that might be the best, solid "bang-for-the-buck"...

I see TonyB2's (?) post in the "technique" thread, but I'd be interested to hear about any digitally-modifeid CVT's in the US.

Powerchip advertises a 13hp & 11 lb. ft gain with thier installation, which rates at just under $38/hp gain; admittedly, I don't know where they're measuring the hp... Maybe $44.54/lb. ft. is more applicable.

That's almost half way to 35hp. Maybe its me, but I'd trust a digital mod over an intake/exhaust mod - and depending on the specific intake/exhaust equipment, it might be more cost-effective.

Here's the info they put out:

http://www.powerchipgroup.com/produc...2003&make=Mini

Hmmm...

PowerChip --> 'UK' link, gives me:
" Powerchip is not currently supplying products to this territory. Powerchip recommends that United Kingdom residents contact Superchips for all their performance chip needs. "

Ok then. Off to Superchips...
Mini Cooper 1.6
+8 bhp
£293.75

Hmmm... gbp36 per hp. Damn, thats expensive!

Trouble with many chip tuners is that they simply tone down midrange and boost high-end, making the car *feel* faster.

I'm only going to faff with the ECU when I can do it myself. And I'm working on that.



Lee

[Electrc109]

Quote: Originally Posted by punkeyfunky

Trouble with many chip tuners is that they simply tone down midrange and boost high-end, making the car *feel* faster.

I don't see that as trouble....I'd rather have a better perfoming car than a car that looks better on paper.