Body Kit / Aero-Dynamics / Peformance Parts

Althou I am no expert with the Prius, I would wager the traditional cold air in and free exhaust out would only have a very minimal impact on the performance of the Prius. A body kit would likely add weight to the car which would probably have a detrimental affect on miles per gallon as well as performance.

I would suspect that being able to switch to electric only mode with a manual switch might provide some short term acceleration benefit at low miles per hour. Hopefully others will chime in with their thoughts as I am a fish out of water with this topic.

 

<div class='quotetop'>QUOTE(tnthub @ Jun 20 2006, 05:40 PM) [snapback]274338[/snapback]</div>

Generally speaking, the purpose of body kits (although this tradition seems to have long past) is to improve upon the vehicle's aerodynamic properties. Also, most pieces today are rather light, weighing in at the same weight, if not less than the stock pieces.

 

<div class='quotetop'>QUOTE(tnthub @ Jun 20 2006, 06:40 PM) [snapback]274338[/snapback]</div>

Actually it's the opposite. The hybrid battery's output is 20kW, while the total output of the MG's (motor/generators) are 50kW. The other 30kW will have to come from the ICE thru the PSD (power splitting device) to MG1 (acting as a generator) to power MG2 (acting as motor). So there are two paths from ICE to the wheels. The mechanical path, and the electrical path (ICE->PSD->MG1->MG2->wheels). Other Prius experts can correct me if I'm wrong.

As for body kit and other performance add-ons, try here http://www.sigmaautomotive.com/jdm/prius/prius0405.php

 

Most aero-dynamic improving body kits aren't to reduce drag but rather to increase downforce. you'd lose some MPG. The Prius is a car that does'n tneed to harness much downforce due to it's weight and general lower speeds. I could see it helping you around a turn better at 50 mp/h if you'd need to to turn suddenly at that speed.

 

<div class='quotetop'>QUOTE(toyo proxes ra-1 rubber @ Jun 20 2006, 07:02 PM) [snapback]274353[/snapback]</div>

Refer to this thread... http://priuschat.com/Increasing-output-fro...tor-t21065.html :lol:
Edit: wow, the mods r fast on removing troll threads!

<div class='quotetop'>QUOTE(toyo proxes ra-1 rubber @ Jun 20 2006, 07:02 PM) [snapback]274353[/snapback]</div>

The EPA did tests on those stuff, and result? Useless.

 

<div class='quotetop'>QUOTE(ScottY @ Jun 20 2006, 06:15 PM) [snapback]274373[/snapback]</div>

It did do something, RESTRICT air and lower performance and MP/G.

 

In traditional, (non-hybrid), vehicles, the tornado disrupts the air flow over the MAF sensor to allow more air than normal into the engine creating a lean condition over the typical stock programming. Since most non-hybrid vehicles are by default slightly rich in their air fuel mixtures to prevent detonation (and warranty claims as a result), sometimes the installation of a tornado can produce some benefit on an otherwise stock vehicle.

However as airflow becomes more important at higher velocities the benefit of the tornado is reduced to the point where the disruptive air flow actually impedes proper detonation of the cylinders creating a loss of performance.

the bottom line, from my perspective, is if the car is worth caring about I would avoid a tornado at all costs. Also, air in must be balanced with air out. I am sure that better airflow through a cold air filter will help as well as possibly porting the exhaust heads/gaskets, or installing true headers, but I really think the gains will be extremely minimal especially when considering the overall expense. Also, most vehicles benefit more from computer tuning changes after cold air and headers are installed. I have no idea if this is possible with the Prius or not. With the GM products that I am aware, aftermarket tuning software is required to take advantage of the modifications and the dealers often do not know about or admit to knowing about any aftermarket products.

 

What if you had a Dry-carbonfiber Kit custom made for it? i know its not cheap. But if it would increase mpg and possible decrease the weight at the same time..it seems like a win win situation.

 

<div class='quotetop'>QUOTE(GasGuzzler87 @ Jun 20 2006, 06:19 PM) [snapback]274374[/snapback]</div>

But...but...The infomercial...Are you saying they *gasp*..lied?!

A friend of mine had one of those on his Cavalier and all it did was cost him the money to buy it. His car actually ran better once I removed it.

 

<div class='quotetop'>QUOTE(toyo proxes ra-1 rubber @ Jun 20 2006, 05:29 PM) [snapback]274326[/snapback]</div>

Hi proxes,
For color pictures of Prius with installed body kit see"need-help-installing- my-body-kit-t19392.html" (JDM kit with factory paint from Sigma) & "kenstyle aero kit for Prius" both in priuschat.
For suspension check out "TRD sportivo shocks and springs"and "My offical Prius mods thread" all on priuschat. Do a search on priuschat for the parts you are looking for. Are you going to the All Toyota Festival in Tukwilla on July2, if five Prius register we qualify for a trophy. Check out our website for information and you are welcome to join our Prius meetup group. www.prius.meetup.com./136.
Bernie
Portland Area Toyota Prius Meetup Group

 

<div class='quotetop'>QUOTE(tnthub @ Jun 20 2006, 07:20 PM) [snapback]274378[/snapback]</div>

Hi tnthub,

I do not believe the Prius has a warm air stove for the intake air, it just intakes ambient temp air from under the hood. There has been a thread about adding intake air heating to improve cold weather mileage. Is that what you mean by " cold air"?

What I was supprised about is that the Prius does not do any ram-air. The air intake is facing rearward up the passenger side of the engine compartment from the filter. I would think maybe a NACA duct in the hood right above the intake, and tubing from the duct to the intake there might help with highway economy by reducing intake back pressure? The issue would be de-watering the intake flow without loosing the ram pressure.

 

It doesn't have a warm air stove by default, but I tried to hack
one together: http://techno-fandom.org/~hobbit/cars/warmair/
which didn't seem to affect power or FE at all, at least at highway
speeds. I might build a better one for next winter to at least
help the warmup cycle go a little faster. I figure, if I've already
made those BTUs, I might as well try to get *some* of them back.
.
If you're really worried about keeping up with the riceboys [why, I
can't imagine], you may benefit from a simple trick to come off the
line faster: hold the brake, and press the gas until the engine
starts. You won't move. Keep the accel held about halfway and when
the time comes, dump the brake and hang on. That'll make all the
things that can produce torque do so at that very instant, in large
quantities, and if you don't chirp the tires you may surprise
the kiddies.
.
But really, do you actually *care*?
.
_H*

 

By "cold air" I mean the actual temperature of the air entering the intake. Cold air is more dense than warm air so it provides a leaner mixture (more air and less fuel), which often produces the effect of better gas mileage and better performance in a traditionally powered (non-hybrid), with stock (OEM) computer tuning.

Winter time fuel consumption is worse in most vehicles but it has far more to do with the fuel temperature and the heater/accessory operation than the temperature of the air. It takes more gas to fill a tank in the wintertime due to increased density. Perhaps this worse differently in a hybrid but after installing cold air systems on many conventional cars I have never seen a decrease in mileage (usually mileage increases by ((1-2 miles per gallon) more in a large engine and less in a small engine). I would be interested in knowing why the Prius mught have the opposite response...

 

<div class='quotetop'>QUOTE(tnthub @ Jun 22 2006, 02:37 PM) [snapback]275389[/snapback]</div>

Well this is very true but air can be too cold. Cold air is denser, but REALLY cold air is wel take water for example. Water is most dense at 37 degrees farenhieght, nobody knows why it just is, then as it gets colder it starts to increase in size rappidly and become bigger than it was when it was warm (why ice is larger than water) You want to warm it to a certain extent, but then take in the cold air. Also it may have something ot do with the lack of moisture in the air during winter. I'm not 100% sure but I have heard of "warm air intakes" that help so it's one of those "you're told all your life about 1 thing, but this proves i twrong" kinda things, I don't get it 100% either. If it were my car, I'd run a CAI and not worry about warmingit at all.

 

<div class='quotetop'>QUOTE(tnthub @ Jun 22 2006, 03:37 PM) [snapback]275389[/snapback]</div>

Hi tnthub,

That is the way the Prius is, out of the box. No mod needed. It does not have a exhaust heat stove like most cars. It pulls ambient air into the air filter box.

Hobbit, does the Prius have an intake air temperature sensor? I think I read somwhere that a Jiffy Lube fowled up the intake air temperature sensor on somebody's Prius by improper engine oil filling (pumping it in so fast it went through the PCV valve into the intake plenum). If the Prius has an intake temp sensor, and the other cars Tnthub has modified do not (as the ECU expects warm air thanks to the stove dashpot), then changing intake air temp on a Prius does not fake out the ECU to burn leaner. Have there been detonation issues with the cold air modified standard cars, or do you have to run higher octane ?

There is another reason colder air could improve mileage.

Denser air will also fit more molecules through the intake valve per unit time. With feedback (O2 sensors) the proper fuel ratio should be maintained, and more gas injected. This should result in higher torque. When the fuel lights off, a higher charge density would result in a higher peak combustion temperature and thus a higher Tin/Tout ratio - better efficiency. This kinda thing is why engine-engineers spend allot of time working on the socalled "volumetric efficiency" through cam profiles and port tuning. Racers typically have a flow bench to check out modifications to the intake and exhaust ports in the cylinder heads to do this tuning on. They can measure the pressure drop across the port at a given flow on the bench, kinda like a HVAC guy does when he sets up duct flows in a building.

Now, this is confusing as Hobbit got the same mileage with cold or warm air. But warm air was warmed by waste heat. Possibly the regenerated waste heat was just as effective as the cold air thermodymic heat cycle improvement ?

This might explain why a small cars about to come out are using exhaust waste heat to preheat engine coolant in cold weather? Why regenerate the heat when the efficiency improvement is no better than the increase in charge density would give. That would be wasting the waste - and reducing engine power in the budget. Other people are working on exhaust heat thermo-electric generators. And the next generation Prius is reported to have a turbo-charger (which if made the right size would improve efficiency).

 

Yes, the Prius has an IAT sensor but no MAP sensor. [but I added
a vacuum gauge so I can keep tabs on that anyways]
.
I'll probably put a warm-air redirect of some sort back in for
winter, since I think it *did* help with warmup. Although trying
to capture waste heat via air intake is probably way less efficient
than via exchange with coolant pipes... but if I do it by modding
how the first heat shield attaches, that may collect enough warm
air to make more of a difference. Just hangin' a pipe in the vague
vicinity of the header may not be sufficient...
.
_H*

 

Next to the cute but limited-utility Honda Insight, the Prius is the most aerodynamic car in production. You likely aren't going to get any signficant improvement here.

 

<div class='quotetop'>QUOTE(GasGuzzler87 @ Jun 22 2006, 04:15 PM) [snapback]275409[/snapback]</div>

Actually many people know why. You should be able to deduce the answer with a good chemistry textbook.