hey i think that our toasters would be more enjoyable if they could acually break 110 without topping out... some one should make a new gear set or something to increase the overall speed so that we can enjoy our turbos when and if they ever get released. if we get a turbo with the stock stuff, if the engine doesn't blow then we will still be doin 75 in 5th gear at 3500 rpms.... what do u think... is anybody up to the challenge

 

Changing the gear ratio to lower the rpm will not necessarily increase your top speed. More than likely, it will reduce your top speed. You can see from the intake dyno's that the power peaks out at about 6000 rpm. Most people are topping out in the low 100's because of drag. Low 100's translates to about ~5100 rpm where the power output is less. XB's that are running faster (~110 mph) have a bit more power (intake, pipe...) and are lowered which reduces drag. This allows them to get closer to that peak power rpm. You would have to go about 120 mph to reach that peak power with the stock gearing. The only way you would reach 120 with the box is with forced induction or going downhill. If you have 150 hp on tap, then the gear change would increase your top speed.

 

"Changing the gear ratio to lower the rpm will not necessarily increase your top speed"

Well said, exactly correct. Physics treats all cars equally the same. Even Model T speed enthusiasts (I am one) run up against this same reality.

 

to add to this the cost of attempting this will be high, new gear sets can run thousands of bucks

brent

 

Actually, it wouldn't be so bad. The Echo has taller final gears than the Scion, so the new gearset could come from the dealer parts counter or, more likely, from a wrecking yard.

I'm tempted to try it just to get the cruising RPMs down. I hate spinning at 3000+rpm on the highway.

George

 

"I hate spinning at 3000+rpm on the highway."

Does the car buzz like a bee at that rpm, or does this 3k+ just seem too busy?

 

i run 4000 rpm at 80mph in the scion....i run at 4300rpm in my civic si at 80mph....these little motors were designed to run at higher rpm's....this isnt a v8 with low end torque so u can cruise around at 2500rpm at 80 on the freeway....welcome to 4 banger land....land of gutless till rpm builds....
which is why i have a greddy turbo kit on order.....waiting waiting waiting waiting....waiting sucks.....

 

this subject was talked about a while ago, becasue I remember posting up.
heres the link:
https://www.scionlife.com/forums/viewtopic.php?t=10288 It talks about lower RPMs

 

I agree.

To get a little more technical:
Maxiumum torque in this small engine occurs up in the mid fours. Taller gearing drops the revolutions even further below maximum torque. In so doing HP falls too, and fuel economy probably suffers. There will be less top end speed. And of course, doggier acceleration and grade climbing ability under all conditions. So yeah, a turbo is in the right direction and gearing up is counterproductive. Gears cannot create -power-. They only multiply torque where the road drives the rubber.

Torque and HP are terms often heard, yet not so often understood. ScionXb04 sure understands what these things mean.

Do all here appreciate the difference between torque and HP as ratings? Take Model T ratings (four cyl too) as an example....

 

While I'm not worried about redlining the xB in 5th gear, the engine tone is a bit much at highway speeds. Making just 5th gear a lower rpm would be nice, I've seen it at 3000 @60 and 3300 @65, haven't went past there yet with brand new xB. I think the openess of the car as well as the minimal amount of material between you and the exhaust makes a normal, small 4 banger sound noisier and strained. So maybe a quieter muffler? With a resonator on the end! Yah, that's the ticket! :D