TC4/TC5 Arm Mod for TC6.1 Worlds
#1
TC4/TC5 Arm Mod for TC6.1 Worlds
I did the TC4/TC5 arm mod for my two TC6.2's and I like the improvement to the car. So I thought I'd do it on one of my two TC6.1 Worlds. So far I have mounted the new TC4 arms to the rear of the car. On the TC6.2, the mod involves using the three dot to the outside arm mounts to widen the rear track. So on the TC6.1 Worlds, I added a .051" thick black spacer to each of the four rear arm mounts. In addition, I am using the bottom hole and the three dot "Short" arm mounts. I used the offset in the rear and the regular mount in the front, just like on a stock TC6.1 in order to get the rear toe-in correct. I am waiting on some TC4 outer arm pins and some 4 degree hard TC5 front hubs to arrive on Monday in order to complete the modification. I'll post more photos when I complete the mod and I will post if it helps the handling on the car. As far as the front track, since the 6.2 uses three holes to the inside, I will be using the non-offset standard arm mounts in the front.
#2
OK, the other parts came in yesterday and I completed the mod. Here's the rear suspension. Nothing alarming here, if you need all the part numbers, look for my posting near the end of the TC6.2 thread. Again, I'm using the bottom hole for arm mounts along with the three dot hangers. I used the offset in the rear and standard in the front to get the proper rear toe-in. I used 2.5mm spacers in the rear, using 2 in front of the arm and 4 behind the arm, just like the 6.2 mod. I also used .039" piano wire cut to 2.2 inches long for the rear sway bar. Actually .047" would have been equivalent to the .039 shorter stock bar, but I wanted to try a softer rear bar just to try and plant the rear of my VTA car.
#3
Here's a photo of the front. I used the 2mm spacer in front of the TC5 arm and the 1mm spacer behind the arm. I also used the bottom mount screw holes along with standard (no offset) 3 dot mount hangars.
Once I put the car on the setup station and got my toes and cambers set, I could not get the front of the car down, I had 7mm ride height even with the shock collars screwed all the way up. So I ground 2mm off the bottom shock eyelet. This is the most effective way of lowering the car. You could cut a partial coil off the spring, but that raises the spring rate and I didn't want that.
And just like on the 6.2 mod, if you use DCV's in the front, you will have to dremel out the TC5 C caster hub to clear the universal joint.
Once I put the car on the setup station and got my toes and cambers set, I could not get the front of the car down, I had 7mm ride height even with the shock collars screwed all the way up. So I ground 2mm off the bottom shock eyelet. This is the most effective way of lowering the car. You could cut a partial coil off the spring, but that raises the spring rate and I didn't want that.
And just like on the 6.2 mod, if you use DCV's in the front, you will have to dremel out the TC5 C caster hub to clear the universal joint.
#4
OK, I ran the TC6.1 with the TC4/5 arm mod this weekend. At first it was a little tail happy, but the track was cold. Unfortunately the best conditions were during the 2nd heat and my transponder wasn't working, so I was hand counted. I can't rely on lap times with hand counting, but I can say that was my quickest run of the weekend putting me 2nd in quals. Sun went down and the track cooled off and the car was a little tail happy again, but I ran some good times. Even with the less than ideal conditions, I was .26 seconds faster than my best lap time. So I'd say the TC4/TC5 arm mod is a good one.
I've now modified three cars this way, two TC6.2's and this TC6.1. The first TC6.2 picked up .25 seconds, the TC6.1 picked up .26 seconds, so that's consistent. My best car (USGT), a TC6.2 only picked up .1 seconds, but like I said, this was my best handling car (even though it has the same setup as the other TC6.2). Well, I think the mod is worth it, however, with the TC7 parts becoming available, I'd probably use TC7 arms as part of the mod.
I've now modified three cars this way, two TC6.2's and this TC6.1. The first TC6.2 picked up .25 seconds, the TC6.1 picked up .26 seconds, so that's consistent. My best car (USGT), a TC6.2 only picked up .1 seconds, but like I said, this was my best handling car (even though it has the same setup as the other TC6.2). Well, I think the mod is worth it, however, with the TC7 parts becoming available, I'd probably use TC7 arms as part of the mod.
#5
Tech Rookie
so will the arm mount set fit a tc5? sorry for being off topic. Just bought a tc 5 and need the arm mounts.