Whats the difference between the street and race MM inserts?

 

The race inserts are going to be firmer than the street inserts.
In theory the firmer the mount or insert is, you'll get less wheel hop but more vibration.

 

how is a firm MM goin to make less wheel hop?

 

Don't know but I just put in the race inserts. The vibration isn't bad at all - the car feels like it's better connected. Buy these and put them in your car. You will not be dissapointed. BTW the install is a cinch.

 

rigth on... i asked this question after i ordered the race MM, so hopefully it doesnt take tooooooooo long like everything else ive ordered. plus the k&n typhoon CAI with it . i was only goin to get the CAI but then i was like if i get the MM too i dont have to pay any more shipping so pick'em up. i always do that.

 

Where'd you order from, MP?

 

turboneonstore

 

Q: Whats the difference between the street and race MM inserts?

A: The street inserts are softer and they are flexible, the race inserts are hard as a rock with little to no flexibility at all.

Q: how is a firm MM goin to make less wheel hop?

A: The insert we are talking about really aren't motor mount inserts, they are actually torque struts. What they do is control and limit the amount of movement that the engine is allowed, mainly during acceleration and shifting. By using these inserts it limits the movement even more and the harder/stiffer the inserts, the less it is allowed to move and flex. This limiting or eliminating of the engines ability to move/flex will also make the car quicker by reducing the parasitic loss of power from ths engines movement (this movement slows down putting the power to the wheels/ground).

Wheel hop is caused by the torque struts allowed movement and flexability of the engine, this is a compromise between control and comfort/isolation of the engine and drivetrains vibrations and movement. When launching hard and the tires break loose and start to spin, wheel hop occurs. When you first launch and the engines torque hits the wheels it feeds back to the engine causing it to move/flex. As this happens it reaches the torque struts limit and then the tires break loose, this is where wheel hop begins. Then as the tires break loose, the torque feedback from the tires to the engine are greatly lessened causing the engine to move back to it's original position (this action counteracts the engines power output, it would be like letting off the gas). When this happens the tires, as they are fighting to gain traction, will get a slight bit of traction causing the torque to once again feedback to the engine making it again move until it reaches the torque struts limit. This series of events continue over and over again until the tires finally gain 100% positive traction. The repeated back and forth movement of the engine is what causes the tires to lose and gain traction over and over again causing them to basically bounce, this is wheel hop. It's just like when your wearing shoes and you drag one of your shoes across a smooth tile floor and they keep grabbing and letting go causing them to lightly hop and skip, much like a smooth rock skipped along water.

Using the inserts in the torque struts, almost if not completely, eliminates the engines ability to move/flex from the torque feedback from the tires to the engine. Eliminating the engines ability to move or flex, also eliminates the tires grab and let go skipping (AKA:wheel hop). Using softer more flexible inserts will reduce the vibrations and sounds from the engine, but it will lessen the chance of eliminating the wheel hop. The stiffer/harder inserts will increase the vibration and noise from the engine, but it will greatly if not totally remove any and all wheel hop.

I hope this helps to shed some light on the whole mount/strut/insert topic.[sm=smiley2.gif]

 

Good write up, RR.

 

second that - nice thorough explanation, rr.

Just want to add that the vibration isn't that bad at all with the race installed.