Hi 440 dart
I agree.....the Wilwood spindle has an extra 1/2" from the center of the pin to the upper ball joint mount....which, can help improve (lower) the instant center on some builds.
With the HDK, on builds that are slammed (low stance).....I like using the basic (common street rod / not brand specific ) 2" drop, but
as the stance goes up, I find it beneficial to also raise the upper ball joint pivot point. I do this by utilizing the Wilwood Pro or other means (extended upper ball joint). On some builds with a high nose....a std NON-drop spindle (Wilwood or basic) is used.
One of questions I ask a potential customer...What stance / front end height are you looking for?....and what diameter tire are you using? From there, I can suggest the best combination for each specific build.
what is fun to me is all these builds are a little different......different strokes for different folks.
