Fays 2 watts link

[GRNOVA]

:twothumbs Just got my universal Watts link from SC&C last night I cannot wait to get home and install it. Looks like it will fit just right. I will post pics later. Thank you Marcus!

[CarlC]

Can you weigh it before installation?

[GRNOVA]

around 30 pounds

[The WidowMaker]

id love to see some pics also. i picked up the bellcrank from jim fay and im in the process of fabbing up the rest. they really dont have one that will fit a chevelle, so its all from scratch for me.

[Marcus SC&C]

You mean they don`t have one that will fit a 2 door Chevelle (the FabFit fits ElCaminos and station wagons already).....yet. Mark SC&C

[GRNOVA]

Just a few Questions about this install it says to have the propeller between 12 and 1 o'clock (top)& 6 and 7 o'clock.(bottom)
When vieved from the rear. Mine are to short do they make longer rods? or is this o.k.? Car is at ride height. What should i do?
https://static1.pt-content.com/images/noimg.gif

[chicane67]

Longer rods...

As soon as you go past 30-35* you fall out of the idea kinematic window for the bell crank. It would be nice to see the bell crank at 12 and 6.

[GRNOVA]

In saying that ,just past 12 o'clock is good, but keeping the rods parallel does not seem to happen. should they be parallel?

[chicane67]

12 and 6 is good... with the links just slightly positive at the bell crank.

The slight positive angle on the links will put them just parallel when loaded under normal driving. but in reality, anything close to parallel is good to go.

[GRNOVA]

I Just got done measuring, I need 3" longer bars and it will be right there.
Thanks, Chicane67

[Twentyover]

12 and 6 is good... with the links just slightly positive at the bell crank.

The slight positive angle on the links will put them just parallel when loaded under normal driving. but in reality, anything close to parallel is good to go.

Don't understand this comment. What does 'links slightly positive' and slight positive angle' mean? In excess of 90 degrees? Less than 90 degrees?

[Norm Peterson]

Slightly "uphill" going from the axle brackets to the propellor connections, so that when the chassis drops a little due to driver (and perhaps other weights) the links will end up horizontal. Actually, and assuming equal length lateral links, it's probably more important to get the uphill inclinations equal than to actually obtain perfect horizontal orientation at any specified ride height. Lack of symmetry will end up making the axle moving laterally as the suspension rises and falls (one of the things a WL is intended to fix).


Norm

[The WidowMaker]

In saying that ,just past 12 o'clock is good, but keeping the rods parallel does not seem to happen.
if you move the bell crank past perpendicular to the ground, its length is no longer 5 or 6" (not sure which bell crank jim sent you), but rather just slightly shorter (a^2 X b^2 = c^2). so you would have to move the axle ends of the links to be this same distance apart.


should they be parallel?
your links must be at equal and opposite angles when at ride height. so they both have to be up, down or parallel to the ground, but they both have to be exactally the same and opposite. all they need to do is be parallel at some point in the usable travel of the watts (determined by length of bell crank and links) regardless of whether or not you'd actually use that travel. meaning that your watts may have 18" of vertical travel in your configuration, but your shocks may limit you to only 6" and perfectly parallel does not need to fall inside this 6".


I Just got done measuring, I need 3" longer bars and it will be right there.
if you look at a watts in motion, you will see that you get lateral migration at the ends of its travel (6" bell crank and 12" links gets you over 15" of travel before migration). the end is when the bell crank and one of the links almost form a straight line. if you look at your picture, it wouldnt take much travel for this to happen. its also the reason why some put the bell crank in the opposite direction. 3" looks like it will put you in the right spot.

also remeber, that with any watts, axle or frame mounted, you will get migration when one tire rises and the other stays the same. i calculated this out to only being about .100 when one shock hit its bump stop at 3" of travel in my setup, but its still there. there will be no migration with equal tire movement.

Tim

[GRNOVA]

Tim,Can you send me a pic of your rear suspension? I am pretty sure I understand what you are saying. If I could move the axel mounts from the
watts link in ,I would, but I ust dont have the room. Between the pig and the shockwaves would correct everything. I am going to see if Marcus
has 12" rod for my app. I appreciate all of the input.
https://static1.pt-content.com/images/noimg.gif

[The WidowMaker]

Tim,Can you send me a pic of your rear suspension?

mine will be identical to this (lateral dynamics watts)

https://static1.pt-content.com/images/pt/2008/09/LD204-1.jpg

if you look closely, the axle mounts are solid, but the roll center/bell crank is not. this is just one example of a system that may not have the bars parallel to the ground at ride height, since both bars are angled down towards the bell crank. these are the required equal and opposite angles.

you also must make certain that the vertical distance btwn the two axle mounts, and the vertical distance btwn the two holes in the bell crank are identical. if the bell crank is installed straight up its no problem, but if its not id do a little trig to find out its angle and length. these must be identical or you WILL get migration.

[MrQuick]

GRNova, are you looking at it at ride height?

[GRNOVA]

yes

[Marcus SC&C]

Getting different length links is no sweat,just give us a call. They`re available in lengths from 4 inches to 8 feet in length. That should have you covered. :) A little tweaking is in order only because it`s a custom,one off install. No biggie.
Guys I know you mean well with all the trig and everything but honestly you`re making it much more complicated than it needs to be. All he needs to do is exchange the links for longer ones, set the bellcrank vertical and the links equal length and parallel to the ground at ride height. It`s all basically 90* angles and simple as dirt. Mark SC&C

[The WidowMaker]

marcus is correct. it really isnt that complicated if you just set it up as he states, and in fact it should be one of your more simple installs.

but, if youre on air ride and going to be running full exhaust, the vertical distance btwn the crossmember and the upper link close up REALLY quick. if you dont want to lower your RC into the ground to keep the bars parallel, just know that there are other options as far as bar angles.

Tim

[GRNOVA]

Thank you Mark for your reply.
I just talked to Jim and he is going help me out.

[Takid455]

.... It`s all basically 90* angles and simple as dirt. Mark SC&C

actually dirt or better yet soil in the civil engineering/ geotech world is quite complex with cohesion, plasticity, structural forces, bearing capacity, ect.. :geek:

[Marcus SC&C]

Admit it, you`re wearing a pocket protector aren`t you? :rotfl: Mark SC&C