Hello all,

I am at the three week mark with the company Prius. My biggest complaint is the fear of getting up to speed when getting on the I-405. Drivers here are just not very forgiving of folks who do not merge well.

I've been searching the threads for any signs of performance modifications. So far, it seems that everyone's idea of performance is with mileage in mind. Has anyone actually tried to boost HP? I could sacrifice a little fuel economy for some peace of mind.

Hi,
Many of the performance improvement maintenance items reduce drag and incrementally, improve maximum performance:

• 0W-20 oil at 3/4 full
• max or 42/40 psi tires
• checking air filter frequently

One Prius owner in Australia has fitted a turbo-charger to his NHW10 (Generation 1) Prius. He reported a significant hill-climbing performance improvement but only a modest acceleration improvement. This makes sense once you understand the Prius transaxle.

The engine power is balanced by MG1 torque in the power split device (PSD.) To draw more torque from the ICE would require MG1 to exert more torque but it is current limited by the MG1 electrical system. Also the ICE is speed limited to 5,000 rpm. The only other torque source is MG2 and it too is limited by the electronics.

The only remaining areas are to reduce the vehicle mass. But I understand the NHW20 Prius already has an aluminum hood and rear hatch. Replacing the doors and striping the interior is about all that is left, along with using smaller, alloy wheels and tires. But the mass reduction becomes problematical.

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

Funny. None of the sports car drivers (including a Mitsubishi 3000 & a couple of BMWs) that my Prius has beaten to the 100-yard mark seemed to think it had any performance problems at all. Of course, they were driving automatics rather than sticks, but hey, I don't hold that against them. };-)

Change what & how I drive, not who I am. Rack 'em up.

Wow, Dave! I'm impressed! Maybe you've got what I like to call a "factory freak" (a vehicle lying beyond the plus three sigma in performance). If that's the case, I've got the minus three sigma...lol! Sometimes I want to jump out and PUSH!

yes im lacking power ... i need more juice in my car it seems that every car on the road can can pass me or cut me off!

Has anyone looked into these for perfomance?? http://www.kelvin.com/ac_rubberbands.html

I have heard many good things about these!

I also have problems getting to highway speeds going uphill - California highways are unique in this way. Everyone has a new car and a lead foot, and you're expected to go from 0 to 75, uphill, in about 100 yards. The Prius just can't do it, but it REALLY can't do it without obliterating your mileage. I try to get some speed up and use the Carpool lane (go sticker!) to make a fast, wide turn onto the ramp to give me some advantage - especially since the Prius accellerates better at 30mph than it does at 10.

What's the fuel cost of turbo charging? I'd love to hear more about that.

Prius 2006, bought September 14:

Hey Soopah,

I haven't had much luck finding many performance enhancing modifications (regardless of fuel economy impact), since I started this thread. In fact, your post is the first serious one I've had in awhile.

Please do post again, if you turn anything up!

Googling turned this up:
http://autospeed.drive.com.au/cms/A_2664/article.html

.au - I gamble this is what Bob was discussing.

Prius 2006, bought September 14:

The entire article series - Parts 1-5:
http://autospeed.drive.com.au/cms/A_2658/article.html
http://autospeed.drive.com.au/cms/A_2659/article.html
http://autospeed.drive.com.au/cms/A_2660/article.html
http://autospeed.drive.com.au/cms/A_2661/article.html
http://autospeed.drive.com.au/cms/A_2664/article.html

Too bad this guy doesn't live around here, I'd consider paying him to mod my car. The list of modifications is pretty serious in order for this to work (replaced the Catalytic Converter even...), so I'd prefer someone with experience doing it once even to a prior model rather than a more general mechanic... .

The best part has got to be part 3 where he admits the Prius computer actually managed to outsmart him. With the high-performance state the Turbo is attempting to create at high loads, the Prius computer was actually noticing and decreasing the amount of fuel intake to match, eliminating the conditions he was going for. He'd get everything tweaked perfectly, drive the car a bit, and it'd be right back to where he started. Too funny.

I was hoping since he worked directly with the fuel tank (the injectors anyway) that he'd have some insight on the mysterious fuel bladder but such details don't appear to have come up.

Obviously if the Turbo's feed involves a more fuel-rich mixture than the Prius normally uses (or "prefers" it seems), that sounds to me like lower MPG. However, his tests actually showed improved MPG over the initial vehicle (in this case an NHW10), which he attributes to a more oxygen-rich burn due to the air being forced into the engine.

The most dramatic improvement is climbing hills at mid-range speeds, because the gas-engine power at mid-range RPMs has been massively expanded. This is precisely what I'd like to see improved to avoid embarassingly queueing traffic behind me on California uphill Freeway onramps - which is most of them.

It appears that to trick the Prius computer he had to put in his own fuel pumps that watch the air intake and ramp up fuel themselves (rather than the Prius computer having sole control). The fuel pumps are capable of a lot more fuel pressure than standard and so everything involved in delivering fuel, and exhausting the results, had to be expanded to handle all the changes.

The Turbo part is just $150, but all those other changes add up to thousands in parts alone.

Prius 2006, bought September 14: