TunedRX300

I found a very detailed dyno chart for 2002 RX300 AWD, 4 speed automatic transmission with 95 RON fuel. This is stock with no modification.

http://www.rri.se/popup/performanceg...1&Flap=Details
According to the dyno graph, max HP band is from 4800 to 5500 rpm. 4000-5000 rpm are RX's sweet range for maximum torque. Powertrain loss is about 20%. Wow, I need to find time to install forged rims, lightweight crank pulley, and forged lug nuts to improve effective hp delivered to those wheels.
If one leaves shift **** at "D" and let the auto transmission shifts from around 3000 rpm, the RX will deliver a mere 94 horse power to the wheels.

Dyno chart in pdf:
http://www.rri.se/popup/performanceg...Flap=Downloads

Lexmex

I have tried at the track out in Toluca, when we had Sunday racing, to shift manually with the lower two gears. I could not get any better time doing it. Right now, even though I some times experiment in warm ups, I use PWR ON and Overdrive OFF running down the entire length of the 1/4 mile.

Granted, D is never the best thing. I do know that with Pheonix's accelerator cable mod, the shifts are much quicker than before. However, a torque converter mated to an automatic transmission is no match for a good driver that can handle a stickshift, assuming the cars have equal power and weight.

With the modification of the air intake that I ran on Friday and Saturday (not the one I just did on Sunday), I noticed my RX felt like it was just going constant speed rather than accelerating for about second or two before shifting into second (near 40 mph). I will have to check this again next weekend and notice the RPMs on the shifts to notice if I feel anything different.

TunedRX300

Lexus actually knows about where the power band are - setting tranny to PWR allows the transmission to shift at a higher RPM shift point compares to leaving it at "D". A higher RPM produces more power.
It is surprising how many RX owners think they are driving around a 220hp powerplant when a MAXIMUM of 94 hp is delivered at wheels if you let RX to shift causally - it hardly ever reach above 3000 rpm.
Anyone else have a different dyno? I would love to see a dyno for RX330...

06Harrier

question: 95hp but what is the torque?
love to do a awd run on a dyno and see

Lexmex

TunedRX300,

I hope to have that dyno done soon (too many other things to do at the moment). At altitude, the horsepower is going to get robbed even more...ouch

TunedRX300

The dyno run above is for a AWD. Torque is flatter than HP, still the sweet range is 4000-5000rpm.
I would love to have Lexmex to dyno and quantify simple improvement such as lightweight rims, and would his exhaust yields less torque at lower RPM but gains on the high RPM side

Lexmex

That is generally true that a wider open exhaust like mine will yield gains on the high RPMS and not on the low ones. There are some vehicles that will rip on me at the starting line and their RPMS peak and I overtake them.

I am going to see if I can find some the lightweight clone rims down here that are so often pirated in design along with Pirelli Scorpion Zero tires (although I do like the Michelin Pilot Sport A/S...they are over $300 USD per tire down here ) and both tires come with the extra 2 layers found in Mexico anyways.

HarrierAWD

In normal driving, only about 1/3 to 1/2 of the power is actually utilized unless the driver has a lead foot.

However, your number appears to be low. Do you have the altitude and temperature? Higher ambient temperature and altitude can reduce performance. Was there a cooling fan in front of the radiator?

I used to get great acceleration at 3,000 rpm in NYC. In Colorado, 3,000 rpm keeps up with normal traffic.

TunedRX300

HarrierAWD,
This is a dyno done by Rototest Research Institute in Sweden. They are a non-profit organization.
They have pretty good white paper on dyno testing, and if you scroll down this link and download the first pdf file. You will see correction formula on page 13, it is used for adjusting temperature, air pressure, and fuel grade differences.
http://www.rri.se/index.php?DN=30

toy4two

The dyno operator must have forgotten to press the POWER button next to the gear selector

TunedRX300

I believe PWR just change the shift point but does not do anything to alter the engine output or make the drivetrain more effecient. The dyno result would not change no matter how you shift.
The driver feels more powerful because the car operates at higher rpm instead of staying at 3000 or below 99% of the time.

To increase engine output, you can:
1) modify the intake, increase the air flow or lower inlet air temperature.
2) modify the exhaust, equal length pipe to the catalytic convertor, increase flow by minimizing bends increase pipe diameter and hi-flow cat.
3) better electrical grounding and power stability delivered the spark: hyper ground, hyper voltage kit.

To reduce power loss by power train.
1) light weight crank pulley
2) reduce rotational mass at wheels: light weight lug nut, rims, tires

To improve better usage of power deliver to wheels:
1) reduce weight
2) improve aero-dynamic: remove mud flap, remove roof rack, close windows, no radio antenna extended

Lexmex

Agree with TunedRX300, PWR won't do anything on a dyno, but it will do something on the track. Try PWR ON and Overdrive button off and floor it at a light. As TunedRX300, mentions that initial bolt or surge is right below 3,000 RPM. Indicidentally, at 3,000 RPM is where most intakes start to make a noise (Weapon-R is the one I am thinking of), but my own start to make an enormous roar as my lower air intake mod has the air reach the engine at about that point on the RPM On a track this just a little after the 60 foot line. The exhaust at WOT will always do it upon flooring it.

Keep in mind, dynos are looking for maximums, no longer how long it takes to reach there. A garbage truck would have a lot of hp on a dyno, but may take longer to reach its high point on a dyno.

TunedRX300

Lexmex, you are right.
Dyno tells the capability of the power at crank or at the wheels. It is graph of HP/Torque vs. RPM.
1/4 miles and 0-60 time factors in time, they are very useful measurement but depends on driver's skills such as how to shift, reaction time, and how fat the drive is.

Lexmex

Exactly,

There are drivers at my track (stick shifting is a pure art to get as much potential as possible), but also others with automatics who just cannot hit the gas right to get it to go and lose their potential on track runs.

There is not much more I can do with that air mod I have now. The real issue is still oxygen content in the air and most of what I am ramming in there right now is not what the engine wants compared to sea level. When the turbo project gets underway, the PVC is getting ditched.

TunedRX300

Speaking of effecient power delievered to the wheels...I found out Tire Rack is offering a ultra lightweight tire by Goodyear Eagle ResponsEdge. 23 lbs for 235/60/18, this will shave off 5 lbs mounted at >16" moment arm over OEM Bridgestone 225/70/16.

This is Goodyear's marketing promo, but still informative, especially the carbon fiber outboad sidewall -> light weight, more power, better fuel effecienty

Eagle ResponsEdge tires feature an asymmetric tread design with solid shoulder blocks and a continuous intermediate rib on the outboard portion to improve responsiveness and cornering stability, while diagonal aquachutes, deep shoulder grooves and TredLock sipes on the inboard portion enhance foul-weather traction. The asymmetric tread design is completed through the use of dual-zone tread compounds with a high-grip sport compound on the outboard portion and a high silica content all-season compound on the inboard portion.

The tire's structure includes twin steel belts cushioned by Goodyear's InsuLayer of spirally wrapped KevlarŽ. Polyester body plies also feature an asymmetric design with a carbon fiber reinforced outboard sidewall to enhance responsiveness and cornering stability while providing flexibility to cushion the ride.