[melgish]

Ok, so yesterday I'm installing fuel, and the attendant tells me my right rear tire is going flat. I thought the car seemed draggy. Anyways back to Toy of M for a nail extraction and a plug. No charge, but sitting there in the waiting room reading the 'benefits of buying my car from Toy of M' my eyes rested upon "free tires for life"

I've read many things here about tires, alternate tires, tire pressure etc etc etc. I'm curious...If someone else is buying the tires, would you stick with the factory defaults or move to a different kind?

And of course, why?

 

[Daniel]

This is interesting, because I find myself about to give a contradictory answer: I think I would rather pay for the best available tires. And yet I have been driving the OEM tires, thinking I'd upgrade when these wear out. Odd, that I would not accept free tires if they are inferior, but that's what I'm doing with the OEM's.

Part of my concern is that "better" tires might not get as good a mileage. My mileage is already "low" (for a Prius) due to a very short commute (4 miles). I think maybe I'll switch when winter is about to set in, rather than waiting for the tires to wear out. I'll probably get the ones john1701a recommended.

 

[AgentElrond]

My wife's 2003 is 18 months old, and while she's only been driving it 6 months, she's noticed a "difference" in wet weather handling - i.e. she doesn't like the response with the OEM tires. We'll likely upgrade them to the Michelin Hydroedge, although whether we wait for the current tires to wear out first will be her call (since it's her car).

 

[Jim Biggs]

Michelin Hydroedge

How do these tires work on dirt roads?
Will they handle the beating?
Thanks,
Jim

 

[john1701a]

I'm at 3,650 miles with the Michelin Hydroedge tires. They work fantastic on dry & wet roads. I especially like the feel when it's raining out. The advantage they provide is quite clear. I obviously haven't had a chance to try them on snow & ice yet, but that will come soon enough... I live in Minnesota. I'm sure they will do great; the tire stats have been right on so far.

I simply have no reason to ever drive long distances on dirt roads. That means I don't even have a basis of comparison either. And no one has even asked that question before. So I can only guess...

The tires have much, much harder rubber than the standard tires, the tread is deeper, and the water channels are ideally angled for corning. That makes it pretty easy to say they are well worth trying.

I don't mind the efficiency trade-off. For my driving, that has worked out to a 1.5 MPG drop.

These are the tires I'll be recommending to others. I'm quite pleased with them.

 

[pshady]

For those of us in mostly dry weather (SoCal), which is the best tire?

 

[SLowen]

I concur with John. I have almost 4000 miles on my Hydroedge tires and they get better and better. With all due respect to John, I am not sure that we are even seeing the 1.5 mpg drop as 1.5 mpg is within one standard deviation of the tank to tank error I experience in fuel economy within a given grade. Also with the tires gripping the road better, I have a tendancy to drive a little harder. John spends much more time with the data than I do, but our numbers are tracking pretty well. I feel very strongly that a small delta in octane will make more of a difference than the tires. 89 octane consistently gives Tideland Pearl 3 to 4 more MPG. I have repeated this experiment at least 5 times now.

But these little details are not as important as the fact that almost any good tire will ride better than what the car comes with. If you are nervous about the tread, you may want to look at the Michelin Harmony or Bridgestone Turanza. The Michelin rep thinks they are a better match for the car, but to my knowledge no one in this forum has tried them. Perhaps you could be the Guinea Pig?

 

[Daniel]

... I feel very strongly that a small delta in octane will make more of a difference than the tires. 89 octane consistently gives Tideland Pearl 3 to 4 more MPG. I have repeated this experiment at least 5 times now...

I have heard that higher octane gas actually has slightly less energy, and that there is no advantage to higher octane in an engine that does not require it to prevent knocking.

Can you give some explanation about how you think higher-octane gas is improving your mileage? I'd gladly pay the difference for the bragging rights to an extra few mpg.

 

[richard schumacher]

For those of us in mostly dry weather (SoCal), which is the best tire?

Driving in Dallas I'm completely happy with the OEM Integra tires. When it rains, I slow down. The nice sharp jolts they provide are ass-urance of high MPG :_>

 

[hyperion]

About the octane rating I could not even come up with an opinion without having any idea of what RPM the engine is operating at. Although the compression ratio is 14/1 (which would automatically call for 93 octane) this would not be necessary if engine is only turning 1500 RPM to charge battery and operate as a secondary "boost" The torque in these cars comes from the electric motor. There are presently just too many questions that the Toyota service managers are not able to answer. About the tires: My car came with Good Years and it looks as though Toyota had many choices.

 

[RSnyder]

. . . Although the compression ratio is 14/1 (which would automatically call for 93 octane) . . .

This is a misconception (unfortunately promulgated by Toyota publications). The expansion ratio is 13/1, but the compression ratio varies from around 8/1 to 10/1. The intake valves don't close until well into the compression stroke. So this engine can run fine on 87 octane.

 

[hyperion]

Thanks Robert, I wish my service manager knew this. Would still love to know the rpm range of this engine. Overhead cams and 16 valves tell me it is on the higher end. Not at all like that in the civic hybrid with one camshaft and eight valves.

 

[Daniel]

According to Graham the range of rpm for the ICE is from about 1250 (?) to 4500 rpms, but if I understand the discussion on his site correctly, the ICE likes to be around the middle of its range or a bit below. But it can vary the rpms of the ICE at any given vehicle speed depending on various factors.

 

[grebe]

wo! reading this post I thought *I* had written it! the EXACT same situation had happened to me! In fact we were going to hit up Merchants today to get a plug. your dealer offered to do it for free!? we're at 9,000 miles, and this is our first "problem", but they never offered to do it for free. We figured Merchants was closer and cheaper, so... i hope the tires don't prove to be this easy to puncture in the future....

 

[RSnyder]

According to Graham the range of rpm for the ICE is from about 1250 (?) to 4500 rpms, but if I understand the discussion on his site correctly, the ICE likes to be around the middle of its range or a bit below. But it can vary the rpms of the ICE at any given vehicle speed depending on various factors.

This is true for the 2001-03 model, but the 2004 model upped the max RPM to 5000.

 

[Daniel]

According to Graham the range of rpm for the ICE is from about 1250 (?) to 4500 rpms, but if I understand the discussion on his site correctly, the ICE likes to be around the middle of its range or a bit below. But it can vary the rpms of the ICE at any given vehicle speed depending on various factors.

This is true for the 2001-03 model, but the 2004 model upped the max RPM to 5000.

Is the rest of the nomograph correct for the 2004? That is, are the gear ratios in the PSD the same?

 

[RSnyder]

Is the rest of the nomograph correct for the 2004? That is, are the gear ratios in the PSD the same?

The PSD gear ratios are the same, so the RPM scale is correct. But I believe the final drive gear ratios and wheel size have chaged, so the MPH scale on the right may not be correct.

 

[Daniel]

Thanks.