If you've been following my build thread, you've known I've been STRUGGLING with front tire rollover while autocrossing. While bumping tire pressures up to over 40psi did help somewhat, it was just covering up the main issue:
The CB/CD front suspension camber curve is not sufficient enough in stock form to keep the tires from rolling over under aggressive cornering.
As it was, I was at -0.5 degrees on the front with static lowering at 13" from hub center to fender. To get a dual A-arm suspesion to work well, -1.5 to -2 degrees works best. More than that, and there's too much sacrifice and not enough gained with a street car on street tires. No, I don't know how much "drop" that 13" hub to fender measurement is. Go get a measuring tape, measure a stock hub to fender measurement, and go measure a lowered car. This is how ALL smart "lowered" measurements are done. Pinch welds and other places of measurements aren't very accurate as they vary from car to car, for obvious reasons. Hub to fender is the most accurate measurement. At 13", I have PLENTY of stroke/travel in the suspension(especially in the rear, holy shit did Honda design a lot of travel back there), I'm not constantly smacking the front UCA into the inner fender(in fact, it's never touched it), I can fit a taller tire if necessary(great for winter)(and I've fit up to a 25" tall tire on it previously), the LCA's stay at a nice angle that's less than parallel to the ground(go educate yourself on why this is good), and it rides nice over the nasty bumps and holes that seem to populate the roads of BorHio.
So, after looking at different solutions that have already been tested(Skunk2 88-91 Civic UCA's, various adjustable upper ball joints and anchor bolts), I still didn't feel comfortable with an adjustable arm. I didn't want to push the whole UCA assembly out further when there's not much room to move outwards in the first place, a la adjustable anchor bolts. The sliding kind is just a really poor solution. The cam adjustable kind are better, but still not the direction I wanted to go. As far as the press-in adjustable ball joint kind... if you can't see the OBVIOUS problem with an adjustable, rotating ball joint, you need to stop now, pick up a book, and see what kind of goofiness that creates with impacts. The Skunk2 sliding adjustable upper control arms are nice pieces, but add TOO much camber, TOO much caster(IMO), and set up a STEEEEEEP curve. Too steep. Too much camber gain from static is also not a good thing.
Yes, there's taller lower ball joints for changing the roll center angle, but I'm not going down that path... yet. Possibly in the future.
So I was stuck looking for a non-adjustable UCA that would fit. We all know EF UCA's will physically fit, so I used this information to my advantage on my search.
While looking around, I came across information that stated that the 90-93 Integras had similar upper control arms to the 88-91 Civics. The information stated that the DA upper control arms on an EF add POSITIVE camber, as well as remove some caster. If EF arms are used on a DA, there is a GAIN in caster and negative camber. If a equals b, and b equals c, than a also equals c. The spacing between the anchor bolts are correct, the arms are just slightly shorter for a nice static camber setting, and have a caster angle that's just about right for a little bit of added steering heft. I like this porridge.
$75.65 later, I had two DA upper control arms from Beck Arnley, model numbers 1024657 and 1024656. Why B/A? Because they're a parts REDISTRIBUTOR, not remanufacturer or replica parts manufacturer. There's nothing wrong with a remanufacturer if QC is high(see Deeza parts), but I've learned to stay the hell away from replica parts manufacturers(see most auto parts store parts, Federal Mogul as well-which includes once mighty Moog). The arms were made in Thailand, and appear to be pretty high quality. Short of a snafu where I was sent an EF arm originially on one side(quick notes- EF's have SMALLER upper ball joints and anchor bolt bushings), which was quickly rectified by rockauto, everything went smooth. I used the Accord anchor bolts, which fit kind of snug, but provided the correct length on the threaded portion of the bolt, as well as shoulder depth and shape. Installation was as easy as previously with Accord UCA's.
Comparison pictures:
Length(the camera kind of over dramaticized the length difference, it's only about 1/2"-3/4" overall length)
Ball joint positioning/caster
Driving thoughts:
HOLY SHIT TURN IN. Love the feel of the additional steering heft. No noticable tire rollover in some aggressive street manuvers. A little darty over some road patches. On-center stability is oh so nice.
TBD: alignment specs. I'll update this tomorrow once I get it re-aligned. Definitely changed the toe angle, as to be expected. The camber gain is definitely there, to MY eyes, looks to be somewhere around -2 degrees.
The CB/CD front suspension camber curve is not sufficient enough in stock form to keep the tires from rolling over under aggressive cornering.
As it was, I was at -0.5 degrees on the front with static lowering at 13" from hub center to fender. To get a dual A-arm suspesion to work well, -1.5 to -2 degrees works best. More than that, and there's too much sacrifice and not enough gained with a street car on street tires. No, I don't know how much "drop" that 13" hub to fender measurement is. Go get a measuring tape, measure a stock hub to fender measurement, and go measure a lowered car. This is how ALL smart "lowered" measurements are done. Pinch welds and other places of measurements aren't very accurate as they vary from car to car, for obvious reasons. Hub to fender is the most accurate measurement. At 13", I have PLENTY of stroke/travel in the suspension(especially in the rear, holy shit did Honda design a lot of travel back there), I'm not constantly smacking the front UCA into the inner fender(in fact, it's never touched it), I can fit a taller tire if necessary(great for winter)(and I've fit up to a 25" tall tire on it previously), the LCA's stay at a nice angle that's less than parallel to the ground(go educate yourself on why this is good), and it rides nice over the nasty bumps and holes that seem to populate the roads of BorHio.
So, after looking at different solutions that have already been tested(Skunk2 88-91 Civic UCA's, various adjustable upper ball joints and anchor bolts), I still didn't feel comfortable with an adjustable arm. I didn't want to push the whole UCA assembly out further when there's not much room to move outwards in the first place, a la adjustable anchor bolts. The sliding kind is just a really poor solution. The cam adjustable kind are better, but still not the direction I wanted to go. As far as the press-in adjustable ball joint kind... if you can't see the OBVIOUS problem with an adjustable, rotating ball joint, you need to stop now, pick up a book, and see what kind of goofiness that creates with impacts. The Skunk2 sliding adjustable upper control arms are nice pieces, but add TOO much camber, TOO much caster(IMO), and set up a STEEEEEEP curve. Too steep. Too much camber gain from static is also not a good thing.
Yes, there's taller lower ball joints for changing the roll center angle, but I'm not going down that path... yet. Possibly in the future.
So I was stuck looking for a non-adjustable UCA that would fit. We all know EF UCA's will physically fit, so I used this information to my advantage on my search.
While looking around, I came across information that stated that the 90-93 Integras had similar upper control arms to the 88-91 Civics. The information stated that the DA upper control arms on an EF add POSITIVE camber, as well as remove some caster. If EF arms are used on a DA, there is a GAIN in caster and negative camber. If a equals b, and b equals c, than a also equals c. The spacing between the anchor bolts are correct, the arms are just slightly shorter for a nice static camber setting, and have a caster angle that's just about right for a little bit of added steering heft. I like this porridge.
$75.65 later, I had two DA upper control arms from Beck Arnley, model numbers 1024657 and 1024656. Why B/A? Because they're a parts REDISTRIBUTOR, not remanufacturer or replica parts manufacturer. There's nothing wrong with a remanufacturer if QC is high(see Deeza parts), but I've learned to stay the hell away from replica parts manufacturers(see most auto parts store parts, Federal Mogul as well-which includes once mighty Moog). The arms were made in Thailand, and appear to be pretty high quality. Short of a snafu where I was sent an EF arm originially on one side(quick notes- EF's have SMALLER upper ball joints and anchor bolt bushings), which was quickly rectified by rockauto, everything went smooth. I used the Accord anchor bolts, which fit kind of snug, but provided the correct length on the threaded portion of the bolt, as well as shoulder depth and shape. Installation was as easy as previously with Accord UCA's.
Comparison pictures:
Length(the camera kind of over dramaticized the length difference, it's only about 1/2"-3/4" overall length)
Ball joint positioning/caster
Driving thoughts:
HOLY SHIT TURN IN. Love the feel of the additional steering heft. No noticable tire rollover in some aggressive street manuvers. A little darty over some road patches. On-center stability is oh so nice.
TBD: alignment specs. I'll update this tomorrow once I get it re-aligned. Definitely changed the toe angle, as to be expected. The camber gain is definitely there, to MY eyes, looks to be somewhere around -2 degrees.
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