This material is Copyright © Protected by the Superformance Owners Association. Please DO NOT copy, reprint or redistribute any of the information, context or data contained on this page in any way

If you own a Superformance
  car and you want to see more,
   We welcome you to
JOIN NOW!
<<< (click the logo to the left)

The following page is just a single example of the vast assortment of technical information within the SCOF members only Technical Library resource...

Over 300 detail and descriptive articles with thousands of pieces of vital information specifically crafted to help you repair, maintain, modify and improve your Superformance car! We spend a significant amount of time, money and effort to produce this specialized and unique service and support for Superformance owners to increase the value of your car, and value of your ownership experience.   Please Enjoy the complimentary Technical Article Below!

SCOF Tech Article: No. 001 of

SUBJECT: Suspension Ride Height Comparison Conversion Chart - Superformance Mk-III Cobras / all years

PROBLEM:
Too low or too high suspension ride height setting can cause damage and ill handling

WHAT'S NEEDED:
Tape measure.

HISTORY:
Sometimes the recommended ride height may seem "higher" than you might normally associate with a Cobra because the Superformance was built around the original sizes of the original Cobra tires which were 275/60-15 on the rear, which are taller than the much more popular and modern 295/50-15 tires. The taller tires fill in the fenderwells more giving you the illusion that the car appears lower, even though the taller tires actually make the car measure higher off the ground. As a side note in history, Hi-Tech's intended ride height "Range" is a little higher than what most of us might expect since when the car was first designed by Hi-Tech back in the early 90's, Jimmy made the car for the only thing he knew, the roads surrounding him and his country. He had no thoughts of being a world wide international company at the time. In his words, "I'm just a road builder that wanted to make a few Cobras". The reality is, South Africa's roads are more like Detroit's. Rough. When we visited the factory in 2010 the first thing I noticed was that all the cars on the road seemed to be set at higher rides heights than in America. So the Superformance Mk-III was built around their local surroundings at the time in South Africa.

So when we "drop" the car's suspension to what "we think" looks good, the SPF suspension is already at the very bottom of the originally designed suspension's travel range. Then when we "slam" them to the ground even further, the negative geometry is off the charts. Any decreased center of gravity gains by lowering the Superformance under the suggested ride height is far over shadowed by the accompanying reduced handling due to the negative suspension geometry as well as the adverse component wear as the car is now being driven at what the factory originally thought was the position where the suspension would collapse to after a full compression hit. They never thought it would be driven at the position every moment of it's life.

DETAILS:
There are many ways of measuring the body or chassis height to the ground, and all of them are inaccurate when comparing car to car since tire type, tire diameter, tire pressure and car weight can alter even two identical car's measurements greatly. Measuring the center of the hub to the frame with the weight on the car is accurate but nearly impossible to do due to the rear tire bulge interference. However, the below chart converts a simple tape measurement into a true chassis ride height number than can be easily and accurately compared from one car to another regardless of the various tire and rim diameters, tire pressures and car weights across the board. (The below chart recommendations are based upon the standard shock extension and compression lengths, with the rear shock mount positioned in the lower OEM location on the frame.)

SOLUTIONS:
  The below chart allows you to measure from the top of the fender lip to the bottom of the lower rim lip to get an accurate comparison to other cars which you can cross reference into other rim diameters as well as the corresponding shock center bolt to center bolt length. Additionally the old common and inaccurate method of measuring from the "fender lip to ground" is included merely as an unofficial reference back when only one type of rim and tire diameters were being used. While there is no one single height that is perfect for every car, the range of recommendation will provide an accurate reference and guideline in which to guide you.

ALL MEASUREMENTS TAKEN WITH THE WHEELS ON THE GROUND AND THE CAR ROLLED FORWARD AND BACK A FEW TIMES!
This eliminates any variances in height due to the bottom of the tires not being able to "slide outwards" when lowered from in the air, thereby giving an inaccurate reading.

EXAMPLE: Top of the Fender Lip to the bottom of the lower rim lip measurement

EXAMPLE: Center of the Top of Shock mounting bolt down to the center of the Bottom Shock mounting bolt

* Center to Center bolt measurement based on a standard shock extension length of 13.75-14.25" front, and 14.75-15.25" rear shocks with the rear mount located at the OEM lowest frame mounting position

The "green zone" is the most commonly recommended range for optimum ride height settings that will apply to 99% of the Mk-III's. This acceptable range may be extended when utilizing shock travels and tire diameters that have been greatly altered from OEM specs. Careful application of any non-standard settings is required.

The front spring moves 1/8" per thread of adjustment and the tire movement is multiplied by 1.31:1
Thus .125" in front spring adjustment results in approximately .163" movement at the tire.

* Center to Center bolt measurement based on a standard shock extension length of 13.75-14.25" front, and 14.75-15.25" rear shocks with the rear mount located at the OEM lowest frame mounting position

The "green zone" is the most commonly recommended range for optimum ride height settings that will apply to 99% of the Mk-III's. This acceptable range may be extended when utilizing shock travels and tire diameters that have been greatly altered from OEM specs. Careful application of any non-standard settings is required.

The rear spring moves 1/8" per thread of adjustment and the tire movement is multiplied by 1.64:1
Thus .125" in rear spring adjustment results in approximately .205" movement at the tire.

Here is just one example of why measuring from the fender to the ground is so inaccurate when comparing car to car. In both photos the fender to lower rim lip measurements (yellow) are IDENTICAL, yet the car on the left with the smaller tire has a shorter fender to ground height (white) than the car on the right with the larger tire. While the ride height of the car is different, the suspension height in relation to the chassis (blue) remains IDENTICAL. The fender lip to lower rim lip ELIMINATES this inability to accurately compare one car's suspension height/geometry to another car regardless of how tall or short your tires are and how much pressure your tires have in them where more pressure could otherwise result in a taller ground height than a lower pressure tire even of the same type, style and brand. For instance, if you use the fender to the ground height on your car which has smaller diameter tires as a recommendation to someone else with much larger diameter tires or with more air pressure in them and they follow your advice and lower their car even more, their much more important suspension geometry, shock travel and suspension to chassis height will now be MUCH lower than your car even though the fender to ground heights may now measure the same. In reality, they are NOT the same! Suspension damage and other issues could occur as a result. By measuring the fender lip to the lower rim lip, you are in effect measuring the suspension geometry height which will easily cross reference from car to car more accurately without any variables that could unknowingly create significant problems to one or another.