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Originally Posted by
Skylerholifield
I upgraded my rims to some Enkei 92 aluminum rims with 195/55 r 15 but now it just seems like my engine is revenge higher at highway speeds
Check:
https://tiresize.com/comparison/
Your new wheels/tires are actually under-reporting your speed compared to the stock size. Driving at an indicated 70 MPH, you're actually going about 3 MPH faster than you were on the stock wheels/tires. Not a huge difference, but it does means higher power requirement, so higher RPM.
There's probably also higher rolling resistance and aero drag with the upgraded wheel & tire which adds a bit more to power requirements at highway speeds.
Again, not a huge amount, but it adds up.
find it hard to keep it at 65-70 mph. Is this normal
Nope. That's weird. The wheel/tire change wouldn't have made THAT big a difference. If the car won't go faster than that, something else is going on.
will the new rims effect the transmission/engines lifespan?
Very slightly higher load maybe equals very slightly higher wear. But not enough to worry about.
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View my fuel log 2014 Mirage ES 1.2 manual: 63.5 mpg (US) ... 27.0 km/L ... 3.7 L/100 km ... 76.2 mpg (Imp)