how hard are these to install?

 

also what do they do performance wise? mpg?

 

The non-adjustable 1.7's are a direct bolt-on. You do need to set the engine at a specific point that is marked on the crankshaft damper, but that is easy. You just pull your valve covers and remove the bolts holding the stamped rockers on. Do yourself a huge favor and check your push rods for straightness. Pull 1 at a time and roll it on a piece of glass checking for any bends. If it is bent replace it. I just replaced all of mine when I put my new HS's on. Removed a potential fail point.

In regards to performance, you achieve more valve lift thereby allowing more fuel to potentially enter the combustion chamber. Basically this mod is a poor mans camshaft upgrade. It does the same thing for a much lower price. I would expect mpg would basically stay about the same, unless you begin enjoying the new found power too much and develop a case of lead foot. Then all bets are off.

 

thanks

 

Here's a how to write up on installing them:

http://www.pavementsucks.com/tech/rollerrocker.php