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gt40
05-13-2010, 10:20 AM
Anyone have a set of scales I could borrow? I need to get the car corner-weighted before Hallett.

GlennCMC70
05-13-2010, 10:47 AM
Need to or want to?
Hallett is not a track where the benifits of corner weighting are gonna show much if any results.

HoustonNW
05-13-2010, 12:43 PM
Need to or want to?
Hallett is not a track where the benifits of corner weighting are gonna show much if any results.

Rookie question: Why is that?

GlennCMC70
05-13-2010, 01:48 PM
This is all just my opinion, so take w/ a grain of salt.

Corner weighting is great, no downside. But its the difference that only shows in .10's of a second.

To me, its only worth it for high speed tracks where you have alot of slip angle. Hallett is more like an autocross track.

For what its worth, I've corner weighted my car two different times. W/ the limits CMC place on the ability to do this, my results were not what we wanted. The first time I un-done it all after 1 track session (Nats 2007). I did it again for Nats 2009 and ended up pulling all that adjustment out just before TWS cause I have had a push issue I was woking out since 2008. Removing the shims resulted in a more nuetral car.
Now my car has many issues that basically calls for a new chassis (long story), so its not the best example of "results for corner weighting". But!!!!! If you think its the reason your 2,3,10 seconds off the lead car, your gonna be highly disapointed.

Wanna be faster? Test a couple days. Tire surface temps are key. It tells if you need more/less camber/caster. Do I have too much air in the tire? Tire pressures between front and rear - are they close? Is the car pushy? Is it really balanced? Am I using all the track from turn-in to apex to track out? I see lots of you newer guys who are doing all or some of the things listed. I also see some newer guys who have done what I've said below and it shows. Corner weighting should be pretty low on the "Things to Tweak" list.

The point of my original post?
Dont think corner weighting the car will be the magic pill. Or the fix for getting faster. The original poster said - "I need to get my car corner weighted before Hallett."
Thus the reason I asked - need to or want to.

RichardP
05-13-2010, 01:55 PM
Need to or want to?
Hallett is not a track where the benifits of corner weighting are gonna show much if any results.

Rookie question: Why is that?


I'm not a rookie and I'm asking the same question.


My $.02 Full corner weighting is pretty subtle and isn't going to show much of a difference unless it's really far off.

I'm also confused why people think that getting corner weights (or diagonals) equal is the best thing. Why do you want the car to turn the same both ways? All the tracks I've driven on have exactly 360 degrees of more cornering one way than the other. It's of course more complicated than that. Some tracks have more important corners that require optimization at the expense of others.

Even as a subtle thing, I believe corner weighting at Hallett is more important than most other tracks. My optimum setup would have a bit of "wedge" in it, though. I know some really fast people at Hallett that would agree with me (on this, anyway).

If you don't get to scales before Hallett, I recommend jacking with the corner weights between sessions just to see what it does to the behavior of the car. If you do manage to get some scales and get your corner weights perfect, I recommend marking where you set things and then jacking with the corner weights just to see what it does to the behavior of the car...


Richard P.

gt40
05-13-2010, 03:16 PM
Glen: "Want to," not "need to".

Richard: I suspect it's way off, and at any rate, so much has been done to the car and its been such a long time since I took corner weights that I want to at least have an idea of where I am and how far off it is. I'm making big changes to ride height in the rear, and I though it would be an appropriate time to measure it too.

I'm not expecting to pick up a second or two from this, it's just something that I want done to tell me where the car is right now and whether something's really screwed up.

I'd planned on doing it at TWS this weekend, but that's not going to happen now. Instead, along with my extensive honey-do list, I'm going to be finishing up my post-race and pre-race car inspection and making some changes to the car (like welding the starter to the engine block -- that will NOT happen again!)

GlennCMC70
05-13-2010, 03:19 PM
Dont feel so bad about the starter. It happened to Matt King too at Nationals back in 2006 during the Championship race.

gt40
05-13-2010, 03:57 PM
Dont feel so bad about the starter. It happened to Matt King too at Nationals back in 2006 during the Championship race.I do feel bad about it. having a 25# chunk of iron and steel bouncing down the track is a problem.

It was entirely my fault. I hadn't checked those fasteners for tightness. they're on the pre-race checklist now and they're getting safety-wired.

GlennCMC70
05-13-2010, 04:48 PM
I think safety wiring is a bit much. Think of all the cars on track who dont have the same issue. If it was a real problem (starter bolts frequently coming lose) then I would understand.
I cant say when the last time I checked something like a starter. Likely the last time I put it on (2007?).
I think its strange how folks who have something like this happen think its an issue w/ the fastener. I would think locktight would be a better more likely answer than safety wire.

gt40
05-13-2010, 05:35 PM
I think safety wiring is a bit much. Think of all the cars on track who dont have the same issue. If it was a real problem (starter bolts frequently coming lose) then I would understand.
I cant say when the last time I checked something like a starter. Likely the last time I put it on (2007?).Same here. I've been revving the motor a little higher than normal lately. I wonder if that's a factor.


I think its strange how folks who have something like this happen think its an issue w/ the fastener. I would think locktight would be a better more likely answer than safety wire.I like safety wire because 1) I can look at it and tell if the fastener has rotated, 2) safety wire works even if the bolt and threaded hole is oily, and 3)I can look at it and know that the anti-rotation element is there -- I can see the wire -- I can't see locktite.

Yes, it's a hassle to work with, especially trackside, but honestly, how often do you replace a starter?

(Having said tht, my replacement starter is guaranteed to fail at Hallett.)

Of course, if safety-wiring the upper bolt is a pain, it will get Locktite, but I'd prefer wire.

gt40
05-15-2010, 09:54 PM
The starter is in. Safety wiring that thing was a pain in the ass...

BlueFirePony
05-17-2010, 02:25 PM
The starter is in. Safety wiring that thing was a pain in the ass...
But like you said, now you have a visual tell-tale if there is some chronic issue there...consider it a bit of piece of mind. After the suspension failure at Houston I've given the car a front to back/top to bottom "touch everything" inspection before each subsequent race. Too much? Probably and I'll eventually get back to the prioritized checklist once I am *comfortable* again.
By the way..planning to dose up on anti-allergy so I don't miss seat time at this fiesta! Viva Hallett!!