I think you should try punching the throttle hard, say, about half way around your very first turn. I think this "the rear end comes out from under you" stuff is just a bunch of malarkey. Or, you could just pull in to your favorite fancy restaurant, throw the kid at the valet station a twenty, along with the keys, and tell him "break it in for me, you'll be doing me a favor." :3DSMILE:

All excellent advice from Chas!

I am searching for the YouTube of PatrickT drifting and throwing smoke around that traffic circle!.:D

Thanks Chas, good advice and I've already followed most of it - have about 85 miles on the car. My first "drive" was about 12 trips up and down my driveway (172' long, so not as ridiculous as that sounds). The reason was it was late in the day and didn't want to get caught out in the dark if I needed to tow it home for some reason. Driveway was long enough to get some speed to hit the brakes hard enough to make sure they at least work. Also, got a feel for the clutch.

The next day I drove about 40 miles by myself and got the car up to 60 and braked hard a number of times, including some down hill braking. All this within walking distance of my house on some back roads. Didn't take tools or a chase vehicle, but had my cell phone and my wife at the ready to come to my rescue if needed. Have a tow strap. Also have been diligent about watching the instruments. You may recall the defective fuse. Fortunately, I was watching the instruments and noticed the temp creep up a bit and shut it down before it overheated. Still waiting on Patrick to conduct the fuse test he suggested.

So, not too bad for a newbie...

Anyone have a good source for this - especially the clear? I checked the web and only found 0.75" x 36 yd, at a price of about $3k (!).

Interesting the concern over corner weight on an assumed street car. Unless ERA missed the manufacturing completely, I don't see how corner weighting is really going to matter much. There are lot's of other assembly tolerances that are taken for granted and are possibly not correct e.g. suspension pickup point alignment, chassis squaring, etc. all of which academically affect corner weight and all should be optimized before corner weighting. Isn't that how Shelby made his living i.e. Cobra, GT 350?

On ride height - The slight rake in chassis is just good setup. We get some component of aero working to push it down (at least at the speeds we can legally drive) and also help with squat.

If we consider track - take a look at this software and consider RC and IC and check the resultant ride height against the manual. Depending on tire height (as an example) things will change.

Circle Track Analyzer Racing Simulation Chassis Setup Software Program

I wish we could find some 1 to 1.5" dropped spindles. We could drop the CG and maintain a great RC.

Except for the entertainment value, not sure any of it pertains much to a street car. Very much applies to a track car - (especially if you build an under powered motor **) )

I think ERA has much balance built into their cars as designed, manufactured, and delivered. If you did not purchase a roller, then suspension blue printing makes sense. If not, other than a very good educational exercise, why bother corner weighting a street bound ERA? I doubt we could tell the difference between one that was, and one that was not, if testing were done legally on the street (that means clover leaves at legal speed).

My 3500lb mustang has not been corner weighted and for what it is and what I do with it (intermediate HPDE) it runs like stink. I would c-weight it, but I have spent a lot of time making it track-able and that is time (and $) stolen from the FIA. (much forgiving to learn in though :))

We'll corner weight the FIA, but we are setting it up for track use. We have taken the time to square the sus pick up points, the steering, bump steer it, square wheel base, etc. IMHO - none of which makes much difference for a street car built to ERA standards following their manual.

Go Stanford - 3:06 to go

drop spindles?



chr

grats to State - great game - 2 great heavy weights.

chr

Everything Cliff said in his post is exactly my experience with mine-in the '90's. Mine was a pallet car, not a factory roller. It has no add-on's but does have magnesium wheels. It's a very elemental car like S/C's were.
I did c/w it and here were the results with 1/2 tank of fuel, batt in trunk and me in it:
CORNER WEIGHT W/DRIVER: LF: 682 / RF: 648 / LR:755 / RR: 748
WEIGHT DISTRIBUTION W/DRIVER: F: 1330- 46.9% / R: 1503 – 53.1%
I made no changes and found it perfect for autox, track days and street.
Those that claim a remarkable transformation in street driving after corner adjustments are deceived by lack of force input of a racetrack. Unless the car is saddled with amenities, sound-deadner, fake aluminum and such, it will be very close right from ERA-and they will all be similar. A good alignment with a performance bias will be much more beneficial to improved 'feel'.
So the improvement after c/w is largely psychological-unless you plan what Cliff does on track.

That's a cross-weight of 49.5%, which is pretty darn good. Several of the Cobras on here have had much, much worse numbers than that. I was one of the first cars to be put on Peter's new digital scales, back in 2006, and Doug was able to get me to 49.9% -- with pretty much the same conditions as yours, except the battery is up front. The difference of .4% is only 11 pounds, which is two gallons of gas. I agree that your car was pretty close to perfect right out of the box, but other cars around here are not so lucky. Maybe most ERA cars are where yours was, maybe they're not. The only way you know for sure is to check.

We should clarify by saying that's true for FE cars with Jag rears.-the FIA Windsors are somewhat different with batt location in the rr wheelwell, forward-mounted gas tanks, 50 pound-lighter rears, and of course engine weight and location.
I wonder if the Wilwoods are heavier than the standard ERA GM fronts?? I started with GMs and they weighed a ton but never actually checked-the Wilwoods came on the second rebuild.

In the case it did not weight well, based on experience with mine, I would pull all the suspension and start checking for squareness of everything associated at the chassis. I would correct that if needed and then build back checking as I go. It has to be in tolerancing stackup and should be corrected, but we are talking something really wild.

I would not discount - why do we disconnect the roll bars for weighting?

I am sure they don't all weight the same, but I would bet they all weight within some acceptable range. The components are jig manufactured.

If I purchased a new one and found such an error, I would be on the phone before the day was over and I would not be happy. After all, I purchased an ERA and waited a year(?) to get it. :)

chr

I know you mean sway bars -- when I think of roll bars, well.... :LOL: If you bought a turnkey from ERA, I agree the weights should be set, and I would bet they are. Anything other than that, then you have to check them. It would be interesting to see, as a lark, just how far off you could get the corner weights and still have the car appear to sit reasonably right.

Good points by both ERA 2076 and Era Charles .
There is a relationship/goal that the suspension guys I know use for initial setup for track cars . The left side tires should have the same front to rear wgt distribution as the whole car and ditto for the right side . However , please note that the LS and RS actual wheel weights may not be the same because the CG`s may be offset .
So , just for the fun of it , I put ERA Charles` weights into my formulas to see how close his car was to the "ideal" setup . Pretty close .
Charles .... per my formula , you should be at : RF @ 656 lbs , RR @733lbs , LF @ 675 lbs and LR @ 762lbs . Your actual weights were RF ... 648 lbs , RR ... 748lbs , LF ... 682lbs and LR .. 755 lbs . The rule we use is , if you are within 10 lbs of the goal , don`t touch the car until you drive it . 50 lbs off , you readjust .
FYI .... my weights were all within 1 to 3 lbs of the "ideal" and the car handled great on the track . Note , I said on the track . I will bet you that a car can be off 50+ lbs and the average driver will never notice it . Also , tell someone his car was off and then say you adjusted it and I bet you he will say it handles better . We did this several times to drivers when i was doing dirt track . :3DSMILE:
I weighed/adjusted my car because : I was going to track it and I had replaced all shocks and springs and the ERA settings didn`t necessarily apply anymore for the heavier springs . They got me in the ballpark for the street , but not where I wanted to be for the track .
BTW , my suspension guy has over 20 years setting up dirt cars , SVRA , HSR cars and NASCAR truck series trucks .

The reason you disconnect the anti sway bars before setting corner weights isn`t because of the bars weight , but to eliminate any possible binding due to links being misadjusted etc . Reconnect the bars after setting the weights and make sure there is no preload on them .
It goes without saying ( I hope ) that all this is done with weight in the driver`s seat and 1/2 to 3/4 tank of fuel .
Yes , I agree that all of this is probably overkill for the street , but after all , these cars are toys for us to play with and experiment on .

You know, it's funny. This topic has come up time and time again over the years. Considering all the money we waste on these cars, why somebody would be reluctant to just pull in to a suspension shop, and drive their car up on the scales and have the guys write the weights down, is absolutely beyond me. I bet a weight check with no adjustments is $50 or less. And that's only if your local club doesn't have a set to loan out. You can then choose to either do nothing, or have them adjusted, depending on your preference. Why would you not want to know? Jeez, it's no different than checking your blood pressure or cholesterol, or the air in your tires. The difference is that you only have to do it once.

My one regret is that I never installed 500-600 pound springs. I ran the more or less 'standard' 250 / 350 combination and for a 'street spring' car it was very controllable on track with TD's and BB's. In later years, I went tracking less and less so never did.
I think several guys ran stiff springs on the street and I think Ernie was one.
Not living in Manhattan, I could have easily lived with it.

My original question in starting this thread was regarding ride height and it somehow morphed into corner weighting, which is fine - lots of good information and debate here. This past Monday I had an opportunity to visit a local race shop. Very impressive - there were 10 - 12 carbon fiber bodied Porsches in there and a couple of street cars - a Ferrari and an Aston Martin. The owner built and owned an ERA a number of years ago. My point is he certainly has a lot of credibility on this topic so I asked about corner weighting. They have scales and a perfectly level floor area for that purpose and routinely corner weight the race cars to within a couple of ounces. He offered to corner weight my car but then added that it isn't worth the effort unless I plan to track the car. I like Patrick's idea of at least knowing how far off it is so I'll get them to put it on the scales this Spring to see where I'm at. As for my original question about ride height, it is now exactly to ERA specs and the alignment is right on.

One thing that suprised me a bit is that the ERA manual indicates rear ride height can be adjusted by changing just one of the double coil-overs on each side. I would have thought it best to keep them exactly the same but apparently that's not a big deal.

Kevin

Not on the ERA rear -- it's only got one shock per side, and the spring on that baby is 550lbs.

http://www.clubcobra.com/photopost/d...gspring001.jpg

Obviously I'm talking about the Jag rear...

Yes, that was the other great regret for Chas... that he never upgraded to the ERA rear.:cool: