The geometry needs to be corrected with the steering linkage pivots. Upper arms can only adjust camber and caster. You are correct that all early Mopars have a limited caster range. However adding caster lowers the outer tie rod. Sometimes that helps, sometimes it makes things worse. Outer tie rod location is critical to bump steer. The QA1 rack and pinion stuff has a horible outer tie rod location. Trust me the stock stuff is very good. Even strong enough for "big wheelies". 2.5 degrees of caster is plenty stable at 150. My experience? 35+ years of racing. Probably 5000 alignments thru my carrer. Along with body shop wreck repair
Doug
Thanks for the advice
In my now 45+ years of drag racing, 20+ races a year from 1977-2007
I was running 8's at 18 y/o
I slacked off after moving to Rancho Murieta, 1997
I did still keep my Pro & comp license current, dabbled in fast cars
for those 10 years, made my street car go in the mid 8's
but not many races a year, maybe 100 1/4 mile N2O passes
& another maybe 200 passes N/A...
I was golfing too much...
Before I moved up here, no tracks very close, still made some 200+ passes
maybe 10+ a year, nothing like I had done before...
I was spending time with family, had neglected before Lisa was gone
the golf, kids & their sports, not racing as much...
Nothing (tracks close either) like like I had in the bay area & Sacramento...
I'm 125+ miles away from the closest track now...
Back then even going running, many different classes & cars
S/ST 10.90, S/G 9.90, S/C 8.90,
even when I lived right next to Polar Raceway in Palmer, Alaska
S/E 7.90 everyone was well over 160
Pro-Gas 8.50, A/Gas 6.90s-190s Altered
7.0s to 8.0s 160-188+ in Outlaw classes
best in a doored car T/S 6.69 @ 217
or 5.95 @ 227 in a 225" RE dragster (not mine)
many fast cars in between, my slower 8-9-10 sec. street/strip stuff, many MoPars
I will say I'm not a front-end or alignment expert, don't/didn't ever claim I was
I certainly haven't aligned 5,000+ cars...
I will say "leave it to the professionals", if you aren't competent in your own skills
or measurements & have the tools to do it correctly...
I do know what works very well on my cars...
I've never tried a QA1 rack or QA1 front-steer type Rack & pinion system
I didn't recommend any either, not to my knowledge...
I haven't used any Mustang II/Pinto stuff either,
and not on any MoPars...
Mostly Capps Automotive, before QA1 bought them out...
Had limited use of Magnum Force Racing components, OK success...
There weren't many companies (not reputable) making anything
suspension-wise for MoPars...
I have done quite a bit of my own fab stuff too...
I have owned & built 26 racecars since 1975...
Some worked some not so great, I'll admit I've messed up here & there
I've made bad purchases in the past too, I don't hold back what I think...
On OE stuff or aftermarket stuff either...
I had run MustangII/Pinto type stuff (not actual Ford OE components)
on quite a few early on (late 70's early 80s),
Tom Alston Engineering's stuff
later his brother in Sacramento, Chris Alston Chassis Works stuff,
it is/was top quality stuff, well into the 90's
on mostly Brand X cars, Pontiac, Chevy, Olds, Buick, Ford, not just MoPars
street/strip, Pro-street 'yes street driven', or on all-out tube chassis real racecars
aftermarket frames/tube chassis, suspension components etc.
with decent success, very lil' street driving on it, mainly track use...
I do have 1st hand experience, also with a bolt-in much lighter replacement
for the heavy OE steering stuff, using a Unisteer Rack 68 RR (rear steer, just like OE)
(
I had said a few times, when asked, or I'd volunteer it, that I wouldn't recommend it,
not as is anyway)
It had a horrid bump steer issue too, easy enough fix, spaced the tierod ends
& the turning radius is horrid too, simple fix, simple redrill...
The worst part is lack of Oil-pan options, with a rack under the pan
where the draglink would be on OE crap...
just edited for clarity... 3:07 pm PST