620 S Build

[CBuff]

So the 620s does have inboard front suspension ?  Is that only R pack or did I miss a change 

[williamwashere]

Great thread, trying to learn a lot here!

[JohnCh]

Improved dampers, along with different spring rates, made a huge difference to my car. It wasn't just ride and wheel control that improved, but traction out of a corner was significantly better when driven back-back with a stock 420R SV running the same tires, air pressures, and alignment settings. This despite my engine producing a lot more power and torque. I'm looking forward to hearing your impressions.

[CarYenta]

1 hour ago, CBuff said:

So the 620s does have inboard front suspension ?  Is that only R pack or did I miss a change 

It is outboard front suspension for both S and R 620. CSR are the only ones with inboard front and IRS.

[CarYenta]

Decided to reduce the ridiculous front camber today. Measured to be -4 degrees approximately each side.

 

"This won't take long", I thought.

 

I then looked at how the upper wishbone track end works to adjust camber and went, "oh nooooo no no no no no. No no no. Why????" Existential screams in the garage.

 

"Ok, I've done many ball joints before, this car is new, should just fall right out".

 

Several hours later after I gave up with my engine hoist idea (don't ask), I decided to read through many cryptic descriptions of ball joint removal on caterhams and other cars for inspiration beyond the hammer.

 

Here's what I came up with (something it seems everyone else also comes up with)

 

 

1) Put nut back on the end of the ball joint to be about flush with the stud.

 

2) Wedge something in there which just barely barely fits

 

3) loosen nut to push down on the thing wedged in there

 

4) wonder if the wedged thing will fly off straight into your face and go find safety glasses

 

5) wonder how hard you should twist the nut before it deforms

 

6) hit the side of the track end again for good measure

 

7) decide to crank harder 

 

8) clap to yourself when it pops off since you're so brilliant as a mechanic

 

9) record the other side so the Internet can high five you

 

10) find out your arm is shakier than Zimbabwean currency when reviewing the footage

 

^^ wedge was a hex socket, 2-1/8" long.

 

I gave the camber track ends 6 complete turns each side. Unloaded (no weight of me in car), the drivers side (right hand drive) has about 2/16" extra distance between upper tire side wall (about 20 inches high off the ground from vertical) compared to the passenger side. When loaded with my weight, the driver side loses 1/16" and the passenger side gains 1/16" so the camber is equalized. Each 360 degrees of the track end changes about 1/32" of length. The final front camber is now about -2.15 degrees according to napkin math which should feel pretty different I'm guessing.

 

Toe went from zero to about 1-3/32 toe in from the camber adjustment. Set it back to 1/32" toe in when weighted.

 

Before and after:

Edited March 29 by CarYenta

[JohnCh]

11 minutes ago, CarYenta said:

I then looked at how the upper wishbone track end works to adjust camber and went, "oh nooooo no no no no no. No no no. Why????" Existential screams in the garage.

 

That's why I had Bruce Beachman install these when he did my alignment. In addition to making camber adjustment easy, it also allows for a 1/2 turn of rotation when setting camber, rather than the ball joint's full turn requirement. 

 

 

 

 

[KnifeySpoony]

Yep, the Jack Web UBJ are great. Super quick camber tweaks  without fighting and swearing.

[CarYenta]

5 hours ago, JohnCh said:

 

That's why I had Bruce Beachman install these when he did my alignment. In addition to making camber adjustment easy, it also allows for a 1/2 turn of rotation when setting camber, rather than the ball joint's full turn requirement. 

 

 

 

 

I don't understand, those appear to also require removal from the upper wishbone and need to be rotated 360 degrees just the same to move inward or outward? Maybe you mean to say the thread pitch is 1/2 that of stock? I like that the upper portion has a place to keep the spherical bearing from rotating, that would save some putzing with an open end wrench and allow a socket to tighten. Does Bruce stock these?

[JohnCh]

The bolt removes through the top, while the tapered part remains in the upright. The rose joint can then be rotated 180 degrees and the bolt reinserted.  

 

I bought them from Jack Webb after completing the build but before I had the alignment done. 

[CarYenta]

11 minutes ago, JohnCh said:

The bolt removes through the top, while the tapered part remains in the upright. The rose joint can then be rotated 180 degrees and the bolt reinserted.  

 

I bought them from Jack Webb after completing the build but before I had the alignment done. 

Oh neat! Removable bolt is nice. Maybe I don't understand fully still, the rose joint part (this is the tapered part I assume you described?) still needs to be broken away from the upright?

[JohnCh]

This is a rose joint (aka Heim joint, rod end bearing). The bolt goes through the top, then through the spacer which is installed in the A-arm, and is held in place with the nut. To adjust camber, simply unscrew the bolt from the nut, lift it out, then raise the A-arm so there is sufficient clearance to screw the rose joint in or out of the arm. During this process, the spacer remains in the upright.

 

[CarYenta]

Got it, wow! Wish I had those this morning.

[CarYenta]

Test drive to get the alignment straight and ended up being snowed upon by flowers

 

With -2-2.25 degrees front camber instead of -4, the car still corners great but if you come in hot where you'd expect understeer, the dynamic is now grippier progressive and less sudden loss of everything. The car wants to turn a bit less, however. It feels more stable on the highway which I prefer. With the MCS 250 lb springs this should be about correct I think.

 

Far less crazy looking now^^

 

 

 

Now if only I could find where this ridiculous rattle is coming from. It seems nearest to the heater core. Unfortunately the heater core is riveted in with some fancy type of maybe rivet. Are these required to be drilled out to remove I assume? Can regular old rivets go in their place?

[11Budlite]

There should be (4) nyloc nuts plus (2) upper screws in the engine compartment holding the heater core assy to the firewall. What you're seeing are (2) bracket assy's with (2) rivnuts/studs per assy that supports the interior ductwork and sandwiches the whole heater assy to the firewall. Pg 31 of the assy guide has a good exploded diagram of the assy.

[11Budlite]

You can see photos of a heater assy with attaching parts at this thread: 

 

[CarYenta]

2 minutes ago, 11Budlite said:

You can see photos of a heater assy with attaching parts at this thread: 

 

Oh wow thank you! I'm glad I asked, I didn't realize that was sticking out in the engine bay right there, was already installed in my roller so haven't futzed with it yet.

[CarYenta]

Drove the car around more with the new camber. It's a bigger difference than I initially realized, there is way way more front end grip! Steering is heavier since there's more contact patch I presume, but the grip is huge.