Tires with different max PSI

[Goldenfrog]

I have 2 different brands of tire on my car. They are all the same size but have different max PSI ratings. The front pair have a max of 44 and the rear set max is 35. I had them inflated to max with Nitrogen today, 44PSI front and 35 PSI back. I was wondering how this might effect safety and MPG of my car.

It's a 1993 Plymouth Voyager with a 2.5l 4cyl. 95% of my driving is under 35mph, short trips where the engine never really warms up. I am guessing under these conditions I'm not going to see any difference in MPG.

I was thinking of trying a hot air intake but I'm unclear as to how that works. I always heard that your car performs better with cooler air from outside the hood.

Any input would be appreciated. Thanks

[MetroMPG]

Welcome to the site.

You might want to check this thread for info about CAI vs. Warm/Hot Air Intake:
Cold air VS Warm Air Intakes - what's the difference?

[aerohead]

Originally Posted by Goldenfrog

I have 2 different brands of tire on my car. They are all the same size but have different max PSI ratings. The front pair have a max of 44 and the rear set max is 35. I had them inflated to max with Nitrogen today, 44PSI front and 35 PSI back. I was wondering how this might effect safety and MPG of my car.

It's a 1993 Plymouth Voyager with a 2.5l 4cyl. 95% of my driving is under 35mph, short trips where the engine never really warms up. I am guessing under these conditions I'm not going to see any difference in MPG.

I was thinking of trying a hot air intake but I'm unclear as to how that works. I always heard that your car performs better with cooler air from outside the hood.

Any input would be appreciated. Thanks

I do not have any current data.The data I do have suggests that while under-inflation robs fuel,over-inflating shows no significant improvement in economy,and can have a deleterious effect on brake bias,effecting oversteer/understeer characteristics of the vehicle.Inflation pressures are established by the carmaker for brake bias,favoring understeer,where the front tires break loose first,and a simple steering input restores direction.Personally,I'd stay with carmaker specs,regardless of max. pressure ratings.Saving a fraction of fuel is not worth your safety.