Dynamometer Results

HS 1.9 Billet Aluminum Rollers with Roller Tips
vs
FIT 1.9 Original Reworked Roller Rockers with Standard Tips

The Rocker Comparison Test was done at an Independent Dyno Centre called "Boostin Oz Adelaide" in SA running a Dyno Dynamics Dynamometer recording in Shoot-Out mode for accuracy and consistency of readings.

A member of the Street Commodores forum "Josh Super6" undertook the comparison testing after having already purchased and installed the HS 1.9's and not been completely satisfied with the results both on the dyno and on the road.

Josh organised the appointment for Friday the 11th February 2005 to trial the differences between the two rocker brands. The tests were performed within 2hours of each other for consistent back-to-back testing.

The Test Vehicle - VS Supercharged V6 Calais with the following modifications already installed:

• Pacemaker Extractors
• Twin 2 ½" Exhaust
• FIT 11psi Pulley Kit
• Factory CAI
• HS 1.9 Rockers

After much research and forum participation Josh discovered the HS 1.9's had a rumoured "valve float" issue in the high rpm ranges, when using stock valve springs.

There was a strong recommendation to upgrade the "valve springs" to heavier duty items, of which cost an additional $400 plus an array of specialist tools and 4 hours installation time required. There was also the possible risk of "dropping a valve" during the swap-over process if something went wrong, and this would mean pulling off the heads to retreive the dropped valve.

After hearing of the dissatisfaction and frustration of the above case, FIT offered to send Josh some sample FIT 1.9 rockers to do some back-to-back testing to compare results on Stock Valve Springs.

FIT knew from prior examples and testing there had been no reported problems with using stock valve springs and revving to redline with no presence of valve float.