I haven't seen all of the videos yet, who's clip had the best shot of your car launching? I think you said your running around 5.50's - 5.60's in the 1/8 mile. Is that without a power adder?
There are so many different factors that work with/against the 4-link settings & can govern how well a given car works in the first 60ft. How much usable power/torque you have at launch RPM, engine set back & height off the ground, shock/strut settings, gear ratio, tire size, etc,etc, etc.
Before you think about making a 4-link change, you might look at a few other things first. Are the slicks fresh? Is the converter OK or going away? Is the rear shock extension valving so loose that the suspension's initial "hit" is too violent and unloads the slicks? Is the rear shock compression valving too tight, causing the suspension to unload when the car gets on the wheelie bars? Are the shocks bottomed/topped out because of springs that are too stiff/weak? Are the front strut's extension valving set too tight & not allowing enough weight transfer to work with your engine's power range to help keep the slicks loaded?
If after some more track testing the car works better with the rear shock's extension valving ending up adjusted to "full tight", (and the car is still on the violent side), you might think about moving the I/C out and/or down some. If it works better with the extension valving adjusted looser than half way (and the initial hit is still real lazy), you might try moving the I/C back and/or up some.
There are a bunch of smart people on this site that will hopefully chime in as well, there is always more than one way to get an adjustable car to hook. More opinions/info is more gooder!
460 street '66 Ranchero.......................finished someday.
460 race '70 Maverick..........................finished someday.
All 'glass Top Sportsman '69 Mustang......ummm, check back when I win big playing the Texas Lotto, or online poker.
page. Some ancient & newer local race video.
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