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My regular driver - Autocross - Roadrace Monza

PostPosted: Wed Jul 16, 2008 1:16 pm
by tinsfci
(This thread started here: http://forums.h-body.org/viewtopic.php?f=41&t=24270)

tinsfci wrote:I myself started racing my Monza in Bracket racing (and still do sometimes), but recently I took it to a "A day at the roadrace track",
and it was... GREAT!! :D

I hope to get some comments on this

/Per


Kenova wrote:Cough it up, what have you done to your Monza. It looks like it is handling those cones with relative ease.
I would like to take my Vega in a Pro-Touring direction and keep an eye open for appropriate modifications. Right now if I push it, it goes into a four wheel slide. I think the garbage tires have something to do with that though.


Actually, I haven´t done much at all with it...yet :) I have Koni shocks f/r, that´s about all. The widened wheels maybe helps a bit too. The tires are...BAD, I guess they are like 15 years old. At least :)

As you can see on this pic, the right front wheel is tilting to much "out"= positive camber=bad (seen from the top):
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That´s probably due to worn out control arm bushings. I plan to put polyerethane there.

Since this pic was taken I also had the front springs cut 1 "whole circle", and the rear springs 1/2 "circle"
I also have tuned the wheel angles to about 2 degrees neagtive camber (wheels are tilting "in" from the top)

And, I agree: Autocrossing/Roadracing is a BLAST!

:D

/Per

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Wed Jul 16, 2008 11:35 pm
by Kenova
When you get a chance, we would like some pictures of your Monza with the shorter springs. Have you had any problems with tires rubbing? What size are they?
The camber problem may be a little harder to deal with. There isn't a lot of camber adjustment in our cars, and they were designed with positive camber gain ( wrong direction ). Lowering your car may have helped a bit. The ultimate solution would be a taller spindle and/or a fully adjustable upper control arm.

Ken

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Thu Jul 17, 2008 6:56 pm
by rpoz-29
Welcome! There aren't many "diehard" autocross/road race types on here. This is more of a drag race site, but a wealth of information none the less. I ran with -2 degrees camber with 1/8" of toe out on my Vega. Honestly, I don't think the car looks out of sorts at all in the picture. What tires are you on in the picture, and what size are they? That's a fine looking Monza!

Bill

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Fri Jul 18, 2008 8:44 am
by tinsfci
Kenova wrote:When you get a chance, we would like some pictures of your Monza with the shorter springs. Have you had any problems with tires rubbing? What size are they?
The camber problem may be a little harder to deal with. There isn't a lot of camber adjustment in our cars, and they were designed with positive camber gain ( wrong direction ). Lowering your car may have helped a bit


Sure, I will post some more pics on the springs and more!
The wheels/tires are:
Widened original steel wheels, 1 3/8 ” front, 1 ¾ ” rear
BF Goodrich Radial T/A 215/60-13 rear 205/60-13 front. These tires are OLD :)

Tire rubbing, do you mean if the tires are like touching the body in corners? Or if the tires are worn on the inside/outside due to the camber angle?
I say "no" to both.
I think the camber (negative) I got is quite satisfactory for me. Maybe I was able to get that negative camber due to worn out bushings or a sagged crossmember, I recall that the H07 are known to that phenomenon. You can buy offset bushings just to "cure" that.

rpoz-29 wrote:I ran with -2 degrees camber with 1/8" of toe out on my Vega. Honestly, I don't think the car looks out of sorts at all in the picture. What tires are you on in the picture, and what size are they?

So you are running toe-out? Will it not be quite unstable at highway speeds, going straight ahead?

My webpage, (badly updated I´m afraid) http://hem.passagen.se/perlon/ is here.

Maybe some of you are familiar with my webpage, it´s been up since 1996 :)

/Per

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Fri Jul 18, 2008 11:12 am
by rpoz-29
The 1/8" of toe out did affect the car on the street especially on expansion strips, but not what I would call unstable. It will get your attention, though! The benefit is that as you begin to make a turn, the inside tire is already making the turn. Are you guys allowed to run on "R" compound tires? When I last ran the Vega, I was on 185-60-13 Yokohama A008RS tires. I stopped running that car in 2002 and started running a 2002 Z-28. I've tried Kumho Victoracers, Hoosiers, and I'm on Kumho 710's now. They're about used up, and I have a set a Hoosier A-6's to put on next.

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Wed Jul 23, 2008 9:58 pm
by mldeolde
I USED A SET OF THE WHEEL SPACERS THAT WERE AN OPTION FOR 75 MONZAS FOR THE USE OF SNOW CHAINS AND WITH THEM WAS ABLE TO RUN THE EVEN LARGER BFG 50 SERIES IN 13 INCH WHEEL SIZE.

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Mon Aug 18, 2008 2:57 pm
by hammerdown7
I think Kenova is getting caster and camber mixed-up. Is your car a V8 or ? I think it looks like it's handling just about right. What size anti-roll bars are on the car?

Dick

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Tue Sep 02, 2008 11:55 am
by tinsfci
Hi again,

thanks for your comments, sorry for the delay in answering... :oops:

I have taken som pics with the shorter springs, I´ll try to post them soon.

About the handling: I think this pic actually lies a bit, I will post some other pics that shows how the body rolls quit heavily during cornering :(

But as I said earlier, I haven´t made much modifications (yet), so I am not concerned about that.

R-tires? Yes, we are allowed to use them, but only in a "R-tire class" I have never run a car on R-tires. For what I´ve heard, that is the biggest handling improvement, even though you will probably fix your suspension as well, because the R-tires makes a sloppy car even sloppier! :)

Yes, It´s a V8-car, I threw the 262 out and put a Chevy 350 c.i. Fuel Injected (TBI) in instead.
Fuel Injection= :dance:

The anti-roll bars is 1" in front and 3/4" rear, in other word, stock.

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Tue Sep 02, 2008 5:00 pm
by tinsfci
Here is a pic after the spring cut
after_spring_cut.jpg
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Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Tue Sep 02, 2008 5:30 pm
by Kenova
hammerdown7 wrote:I think Kenova is getting caster and camber mixed-up.
Dick


No confusion. The caster problem with our cars can be fixed with a fully adjustable upper arm, but the camber gain can only be fixed with a taller spindle or taller ball joints.

If you take a close look at the first photo Per posted, you will notice that the outside wheel and tire is ever so slightly tipped outward at the top as the car rolls in the corner. This is the "wrong " way for a car set up for handling. With a taller spindle or taller ball joints, the top of the outside wheel and tire will tip inward at the top keeping the tire more square to the ground, aiding traction.
Of course, with so little adjustment in our suspension, you would need fully adjustable upper arms to accommodate the taller spindle assembly.

Ken

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Tue Sep 02, 2008 8:01 pm
by spyder_xlch
Camber AND caster can be changed with adjustable arms. If you move only the front or rear on the control arm you change caster, if you move both the front and rear of the arm you change camber.

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Tue Sep 02, 2008 9:53 pm
by Kenova
spyder_xlch wrote:Camber AND caster can be changed with adjustable arms.


:bang: You're right. I was in a hurry and failed to mention I was referring to camber gain. Let's see if I can do a better job the second time 'round. :mrgreen:

As a wheel and tire moves up and down in it's travel, the top of the tire will tilt in or out. This is referred to as "camber gain", not to be confused with static camber which is set on the alignment rack. Most of the early cars, such as ours, were designed to have the tire tilt out at the top (positive camber gain) as the suspension is compressed, which happens to the outside front tire when cornering hard. This causes a loss of traction that the driver feels as under steer.

When a taller spindle or ball joint (compared to the original) is used, the outside front tire will tilt out less or even tilt to the inside (negative camber gain). This will keep the tire tread more square with the road, improving traction to the point where under steer can be eliminated if desired. The taller the spindle and ball joint assembly is, the more likely you will need the fully adjustable upper control arm.

The beauty of building in more negative camber gain is that you wouldn't have to run massive amounts of negative static camber, which can cause a very uneven wear pattern on the front tires.

Just as toe-in can change with suspension travel (felt as bump steer) so can camber. Although caster can change too, it is usually an insignificant amount.

Clear as mud, right?

Ken

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Fri Sep 12, 2008 1:21 am
by tinsfci
Here is a link to some pics and films of me and other cars from that AutoX the picture posted earlier is from:

http://www.lanechoice.net/RACE/2005/RS5/

The four thumbs below on that page is short filmclips

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Fri Sep 12, 2008 2:40 pm
by rpoz-29
I love seeing your Monza amid all the other cars. I think you need a set of Hoosiers!

Re: My regular driver - Autocross - Roadrace Monza

PostPosted: Thu Sep 18, 2008 4:36 pm
by tinsfci
I promised to show some pics when you see that my Monza could need some handling improvements:
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These pics were taken last year, before I had the springs (front/rear) shortened. I´ve also adjusted the Koni´s to a be a bit firmer.

You can clearly see the body tilt quite a bit.
Note for instance the right front wheel in the last pic, not much contact there...

But it´s fun anyway :)

/Per