Watts Link, No joke..... Options

[sgarnett]

What's the scoop on weight of this setup vs. a panhard? Anyone got numbers yet?

added weight
Watts frame: 11 3/4 lb
link assemblies, total for pair: 3 5/8 lb
axle clamp assemblies, including rod end and mounting bolts, total for pair: 10 3/4
bellcrank assembly, including rod end and mounting bolts: 2 1/2 lb

removed weight
"upper PHR" brace: 4 1/4 lb
LG/G2 aluminum PHR w/ aluminum rod ends, including bushings and driver side bolt: 2 3/4 lb

I used a medical balance beam scale with 1/4 lb graduations. My PHR probably is/was lighter than typical. The aluminum rod end bodies are definitely lighter, and I suspect the swedged tube uses thinner walls than the typical smaller diameter, straight tubes.

I did not weigh the mounting bolts that are reused.

BTW, both the stock driver side PHR brace bolts and the replacements supplied by Fays2 are too large to fit. Or at least, they were too large for my car - YMMV. I used M10x25 grade 12.9 "zinc plated" socket-head cap screws (machine screws) from McMaster. They show up as plated as you drill down through the part selection, but when you get to the final part and pull up the spec, they actually have a zinc-flake coating of some sort, which should reduce embrittlement concerns. I ordered both 25m and 35mm. While they were the same brand, the 25s were made in italy and the 35s were made in Tiawan. The threaded plate that the bolts go into probably won't withstand sufficient torque (the factory spec is only 35 lb-ft) to properly load grade 12.9 bolts, so the split washer is important for maintaining some tension. I used the black oxide finish, "high collar" (made for use with small head machine screws) M10 split washers from McMaster, directly under the bolt head . I also used some extra-thick, hardened 3/8" Lawson washers I had on hand, under the split washers, so the slotted holes in the Watts frame won't break the spilt washers.

A 3/8" drive, long 8mm hex drive bit (also from McMaster) will come in handy if you use a torque wrench (IMG:http://www.frrax.com/rrforum/style_emoticons/default/wink.gif)

There's a seam in the chassis just inboard of those driver-side bolts. If you look closely or use your fingertips, there's a short tab that protrudes a little above the seam. I ground down that tab a little to avoid interference, but left the rest of the seam alone.

The swaybar shims provided by Fay are only 3/4" wide. That's about right for the stock rubber bushings, but for typical poly bushings, it's a little skimpy IMHO. I made my own from the 1.5" wide stock carried by Metal Supermarkets. They cut the pieces to length, so all I had to do was drill them.

This post has been edited by sgarnett: Oct 6 2008, 05:19 AM

[Sam Strano]

Howdy,

More SP legality questions...

What rule allows you to remove the bolt in panhard mount brace that goes from the factory frame rail on the left to the panhard mount bracket on the right?

Mark

15.8.H.1

Or is there something overly vague about "Addition or replacement of suspension stabilizers (linkage
connecting the axle housing or De Dion to the chassis, which
controls lateral suspension location) is permitted."?

[Sam Strano]

Drove the car, as did Brian, Pat and maybe a few others back to back with 2 other "strano" standard cars. Ran pretty much the same times, but John's car needs a little more dialing in. Brian's and Karl Bender's cars are working great, and I matched my time in those cars with John's. Considering this is but the second time out for the car, and was on tires not quite as new (but not bad) as Brian's and Karl's I'm encouraged.

The setup needs a little dialing in. I had John move the RC up to the top hole as the car was just a little too tight, and that helped the car out. But considering we started with EXACTLY the setup we have on Karl Bender's car with a PHB more speed is there to be found. Both Brian and I had had driving position issues in John's car (he has a street Recaro) and we both found the position to be awkward. That does effect the speed, as I later drove another car I setup, again almost identical to the others but with a stock seat and couldn't run the time I could in the other cars, and it turned as well. I just couldn't drive it as well.

All in all the back of car is definitely different, and it's not far off. The change of one hole up in RC height helped it a lot in and of itself. The balance got better and the the rear was better stuck. We need to play with tire pressures and shock settings a bit more, but it'll be pretty easy to dial in based on what I felt and the speed the car exhibited vs. a known, fast setup.

[Sam Strano]

FWIW, it might be time to move this to the Suspension section.... (IMG:http://www.frrax.com/rrforum/style_emoticons/default/smile.gif)

[shortbus]

Hunt, poke. Double post.

This post has been edited by shortbus: Oct 6 2008, 05:35 PM

[marka]

Howdy,

Howdy,

More SP legality questions...

What rule allows you to remove the bolt in panhard mount brace that goes from the factory frame rail on the left to the panhard mount bracket on the right?

Mark

15.8.H.1

Or is there something overly vague about "Addition or replacement of suspension stabilizers (linkage
connecting the axle housing or De Dion to the chassis, which
controls lateral suspension location) is permitted."?

For sure that allows you to remove the panhard bar and replace it with a watts link. But I don't know that its a slam dunk that the upper panhard brace on the car is part of the panhard, vs. part of the car's chassis.

It'd make me nervous enough to want a clarification anyway.

The answer to that would probably also dictate if it was legal to cut the old panhard mount off the axle.

Mark

[shortbus]

Howdy,

Howdy,

More SP legality questions...

What rule allows you to remove the bolt in panhard mount brace that goes from the factory frame rail on the left to the panhard mount bracket on the right?

Mark

15.8.H.1

Or is there something overly vague about "Addition or replacement of suspension stabilizers (linkage
connecting the axle housing or De Dion to the chassis, which
controls lateral suspension location) is permitted."?

For sure that allows you to remove the panhard bar and replace it with a watts link. But I don't know that its a slam dunk that the upper panhard brace on the car is part of the panhard, vs. part of the car's chassis.

It'd make me nervous enough to want a clarification anyway.

The answer to that would probably also dictate if it was legal to cut the old panhard mount off the axle.

Mark

OML.

The rule includes the bracing. It is obvious that that bar serves no other purpose then to support the panhard bar.

[BigEnos]

Drove the car, as did Brian, Pat and maybe a few others back to back with 2 other "strano" standard cars. Ran pretty much the same times, but John's car needs a little more dialing in. Brian's and Karl Bender's cars are working great, and I matched my time in those cars with John's. Considering this is but the second time out for the car, and was on tires not quite as new (but not bad) as Brian's and Karl's I'm encouraged.

The setup needs a little dialing in. I had John move the RC up to the top hole as the car was just a little too tight, and that helped the car out. But considering we started with EXACTLY the setup we have on Karl Bender's car with a PHB more speed is there to be found. Both Brian and I had had driving position issues in John's car (he has a street Recaro) and we both found the position to be awkward. That does effect the speed, as I later drove another car I setup, again almost identical to the others but with a stock seat and couldn't run the time I could in the other cars, and it turned as well. I just couldn't drive it as well.

All in all the back of car is definitely different, and it's not far off. The change of one hole up in RC height helped it a lot in and of itself. The balance got better and the the rear was better stuck. We need to play with tire pressures and shock settings a bit more, but it'll be pretty easy to dial in based on what I felt and the speed the car exhibited vs. a known, fast setup.

Yeah unfortunately I didn't get a chance to run the car with the RC raised so I don't think I have a good feel for the advantage of the watts vs. phr. With the lowered RC the car just pushed and was generally unresponsive. It was a no-brainer to slalom but it would give it all back in sweepers. Oddly, the rear would stick well but then let go violently if you really tried to make it move around. I was able to run within about .5 of my fast time in my car in two runs in John's. I don't know what Sam ran ultimately in John's car.

Bravo on the course design, Sam. It had a little bit of everything and was a lot of fun.

[sgarnett]

So far, events have conspired against any competition Watts testing for me.

However, based on my testing with the PHR lowered a little (not roadkill-scraping), you might want to try a Hotchkiss rear bar (or the ST bar, but I think it's going to be a lot heavier) before giving up on the lowered roll center (IMG:http://www.frrax.com/rrforum/style_emoticons/default/smile.gif) That should allow you to run the roll center about 1" lower, plus/minus 1/2", with no other changes.

[Sam Strano]

First of, if anyone wants to try a 25mm hollow bar, we have those from both Hotchkis and Addco.... (IMG:http://www.frrax.com/rrforum/style_emoticons/default/smile.gif)

But I don't think anyone wants to spend money before they need to, and the car is damned close as is w/a 22mm bar. Witness the fact both Brian and I ran similar times in John's car to Brian's and in my case including another car too. That can't happen if we're way off, and I did drive John's after raising the RC height and it was better.

And fwiw my rational for the Watts isn't to get a lower RC. I'm very happy with the balance where it is. It's to get rid of the jacking and lateral movement of the PHB. I don't want to change the suspension setup all around, and don't feel we'll need to unless someone does opt to slam the RC down.

[shortbus]

First of, if anyone wants to try a 25mm hollow bar, we have those from both Hotchkis and Addco.... (IMG:http://www.frrax.com/rrforum/style_emoticons/default/smile.gif)

But I don't think anyone wants to spend money before they need to, and the car is damned close as is w/a 22mm bar. Witness the fact both Brian and I ran similar times in John's car to Brian's and in my case including another car too. That can't happen if we're way off, and I did drive John's after raising the RC height and it was better.

And fwiw my rational for the Watts isn't to get a lower RC. I'm very happy with the balance where it is. It's to get rid of the jacking and lateral movement of the PHB. I don't want to change the suspension setup all around, and don't feel we'll need to unless someone does opt to slam the RC down.

I tried a 22mm solid bar.

(we had a test and tune)

I moved the pinon down 3 holes to get back to my liking. So, it was lowered 1.5 inches.

With the car like this I was lifting inside front wheels on corner exit.

[JimMueller]

With the car like this I was lifting inside front wheels on corner exit.

Err, that's desirable? (IMG:http://www.frrax.com/rrforum/style_emoticons/default/unsure.gif)

[marka]

Howdy,

OML.

The rule includes the bracing. It is obvious that that bar serves no other purpose then to support the panhard bar.

So does that mean that I can completely cut off all the panhard brackets on the car, and completely fabricate my own from scratch?

If I thought it was obvious, I wouldn't be asking. This is the same class where some people consider welding to not be an allowed method of update / backdate and also where the amount of metal in a bushing must remain the same as stock.

Mark

[sgarnett]

First of, if anyone wants to try a 25mm hollow bar, we have those from both Hotchkis and Addco.... (IMG:http://www.frrax.com/rrforum/style_emoticons/default/smile.gif)

But I don't think anyone wants to spend money before they need to, and the car is damned close as is w/a 22mm bar. Witness the fact both Brian and I ran similar times in John's car to Brian's and in my case including another car too. That can't happen if we're way off, and I did drive John's after raising the RC height and it was better.

And fwiw my rational for the Watts isn't to get a lower RC. I'm very happy with the balance where it is. It's to get rid of the jacking and lateral movement of the PHB. I don't want to change the suspension setup all around, and don't feel we'll need to unless someone does opt to slam the RC down.

Oops, I thought the 25mm solid bar you carried was the ST, not the Addco.

At any rate, my reason for suggesting the Hotchkiss bar was not that it is needed to fix the Watts at all - it certainly isn't "broken". As you said, the pivot can be tweaked to restore the balance with everything else unchanged. In fact, tweaking the roll center height with the Watts is even quicker than swapping bars.

In contrast to my earlier tome, this is not an attempt at unbiased overview. It is my biased opinion based on previous testing. As I said though, I have not yet tested it in anger on the Watts. In my opinion, lowering the roll center a little (not slamming it all the way down) and rebalancing it with the larger swaybar makes the car easier to drive compared to the higher roll center with a smaller bar (springs and shocks the same, and resulting balance roughly the same in either case). At least, that was the case with the PHR. I aSSume it will work that way with the Watts as well. Time will tell.

I agree that you have never promoted the Watts setup as a way to change the roll center. I, on the other hand, purchased it partly because it allows changing the roll center quickly, and in relatively small increments. Nobody needs to do that; it's just an option available to anyone who wishes to capitalize on it.

[sgarnett]

I tried a 22mm solid bar.

(we had a test and tune)

I moved the pinon down 3 holes to get back to my liking. So, it was lowered 1.5 inches.

With the car like this I was lifting inside front wheels on corner exit.

That seems a little low for that bar. Do you mean three holes down from the top, or three holes down from the center of your former PHR (ie from a string connecting the bolt holes)?

[Sam Strano]

With the car like this I was lifting inside front wheels on corner exit.

Err, that's desirable? (IMG:http://www.frrax.com/rrforum/style_emoticons/default/unsure.gif)

Depends who you ask... I don't think so, but shortbus tends to march to his own beat.

[Sam Strano]

Howdy,

OML.

The rule includes the bracing. It is obvious that that bar serves no other purpose then to support the panhard bar.

So does that mean that I can completely cut off all the panhard brackets on the car, and completely fabricate my own from scratch?

If I thought it was obvious, I wouldn't be asking. This is the same class where some people consider welding to not be an allowed method of update / backdate and also where the amount of metal in a bushing must remain the same as stock.

Mark

I don't know and don't care. It's not relevant to this conversation as you aren't cutting *ANY* of the brackets off the car, and the Watts link directly bolts the the mounting location the upper PHB brace does so it is replacing, not removing.

[Sam Strano]

First of, if anyone wants to try a 25mm hollow bar, we have those from both Hotchkis and Addco.... (IMG:http://www.frrax.com/rrforum/style_emoticons/default/smile.gif)

But I don't think anyone wants to spend money before they need to, and the car is damned close as is w/a 22mm bar. Witness the fact both Brian and I ran similar times in John's car to Brian's and in my case including another car too. That can't happen if we're way off, and I did drive John's after raising the RC height and it was better.

And fwiw my rational for the Watts isn't to get a lower RC. I'm very happy with the balance where it is. It's to get rid of the jacking and lateral movement of the PHB. I don't want to change the suspension setup all around, and don't feel we'll need to unless someone does opt to slam the RC down.

Oops, I thought the 25mm solid bar you carried was the ST, not the Addco.

At any rate, my reason for suggesting the Hotchkiss bar was not that it is needed to fix the Watts at all - it certainly isn't "broken". As you said, the pivot can be tweaked to restore the balance with everything else unchanged. In fact, tweaking the roll center height with the Watts is even quicker than swapping bars.

In contrast to my earlier tome, this is not an attempt at unbiased overview. It is my biased opinion based on previous testing. As I said though, I have not yet tested it in anger on the Watts. In my opinion, lowering the roll center a little (not slamming it all the way down) and rebalancing it with the larger swaybar makes the car easier to drive compared to the higher roll center with a smaller bar (springs and shocks the same, and resulting balance roughly the same in either case). At least, that was the case with the PHR. I aSSume it will work that way with the Watts as well. Time will tell.

I agree that you have never promoted the Watts setup as a way to change the roll center. I, on the other hand, purchased it partly because it allows changing the roll center quickly, and in relatively small increments. Nobody needs to do that; it's just an option available to anyone who wishes to capitalize on it.

I've got both hollow and solid 25mm's if that's what folks want or need.

I understand where you are coming from, and it's a sales point for those that want to lower the RC height easily. John changed his yesterday in 10 minutes or so. While that's not really any easier than moving a PHB up and down you don't have the welding required to install PHB mounts and you get more fine tunable adjustment (smaller movements).

Again, for me it was more about getting rid of the jacking effect and the arc of the PHB. The balance of the cars is exactly what I want now. Given my Camaro has been laid up for a while, it was a sweet reminder of just how happy I am with my setup stuff. I got in Karl's car and it felt EXACTLY like my car when it's not broken, and I ran a time that PAXed favorably against what I ran in the Shelby (yep, drove that too). Admittedly I was a little rusty as the ESP F-bodies and the Mustang do drive differently.

[ESPCamaro]

With the car like this I was lifting inside front wheels on corner exit.

Err, that's desirable? (IMG:http://www.frrax.com/rrforum/style_emoticons/default/unsure.gif)

Some cars it is almost if not unavoidable.....In a BMW you will simply be throwing away grip trying to tune out an inside front lift......But in these cars there isn't enough weight transfer normally to lift an inside front completely up. Let alone all the time. Your giving away some grip there friend. If not by eliminating any load carrying ability of the inside tire, then by having the outside tire carry ALL the load....








Sam what's wrong with your car?

This post has been edited by ESPCamaro: Oct 6 2008, 10:38 PM

[Cr0usEEE]

[Sam what's wrong with your car?

Apparently Sam's car doesnt like poles...and im not referring to the people from a country between Germany and Russia