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Discussion Starter #1 (Edited)
https://en.wikipedia.org/wiki/Sampson_Air_Force_Base
Videos to follow after editing
The plan was to meet @dobrostang and cruze up together "rat pack" style . But he had some last minute Holley issues( insert jokes here). So I went ahead solo, He was however able to get it fixed and just made registration in the nick of time.
I started of my first few runs kinda fluffing because the last time there I ended up with all DNF's getting lost on course partially because some Wile E. Coyote Super genius decided on some last minute cone/course revisions. I wanted to at least not end up with all DNF's again
I'm not the fastest guy out there (slow :1 steering box with Shelby quick steer kit) But I have fun trying to beat my own time and see how close I can get to dobrostang. I mentioned to a fellow autoxer today about dobro being my autox mentor they in return mentioned something about old age and treachery :wink:
At the rate I was improving today especially (after getting a ride by the master) I think If I had more runs he might have been in trouble :shrug:

Live Results - Generated:Sun 07-14-2019 16:27:37, #4 - FLR4 - Sun 07-14-2019

Oh and the best part race on Sunday Drive it to work on Monday
 

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I will tell you all that Holley clear sight glasses don't last for ever, nor do the seals on floats. I had one disintegrate and clog the float e.g. flooding. Love having an electric fuel pump! So I had to clean out the float bowl and fabricate some plugs for the float holes but all is good. The sight glasses were like they were made of rubber, you could squish them in your fingers easily. Guess you only get 20 years out of a set, frankly I was also using the same floats those 20 years. I like to get my $$$ out of things ;o)


This year I'm in a situation where I havn't been able to get my car out till this weekend. Man it was good her rumble! Such a great motor, always starts (knocking on wood) takes a licking riding the rev limiter through the lights 4 times Sunday. Felt good to be flooring it and letting it roar. Car handles well but still tends to push. I'm thinking I need to slim down up front and get rid of the 351 and move to a 347.



Good day at the autocross but I spent the day over-driving my car and mowing cones, but it was good to get out! Pushing too hard with the operative word being "pushing".



I rode with Brad once in the afternoon and he was being way too cautious so I had him ride with me the next round to give him a lesson in pushing too hard. His car sure pulls nicely, his Exploder motor with Performer heads pulls respectably and his car handles very well. He took a full 6 seconds off his next run. I wish I had a photo of his face as he pulled back onto the grid to park. He was ear-to-ear...
 

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Discussion Starter #4
Awesome! Glad to see you guys out there having fun. Post some pics next time :)
Videos to follow just waiting for my daughter to come home for the weekend .
The way the coarse is laid out on the air strip isn't real pic friendly though
accept if I recall @dobrostang 's job as a coarse worker was escorting a photographer ? do you know if they got any ?
 

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Videos to follow just waiting for my daughter to come home for the weekend .
The way the coarse is laid out on the air strip isn't real pic friendly though
accept if I recall @dobrostang 's job as a coarse worker was escorting a photographer ? do you know if they got any ?

THey post them somewhere on the site but only selectively. She did a photo shoot of my car out on the tarmac at the end by the turnaorund. WIsh I had some of those shots.
 

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So was this Autox on concrete? I'm registered for an event at the Grissom Areoplex, formerly part of the Grissom AFB on Aug 4th if I get my car back together. I hear concrete offers a whole new level of grip and ways to break stuff!:grin2:
 

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Discussion Starter #8
So was this Autox on concrete? I'm registered for an event at the Grissom Areoplex, formerly part of the Grissom AFB on Aug 4th if I get my car back together. I hear concrete offers a whole new level of grip and ways to break stuff!:grin2:
It's a little bit of both ,the "runway"proper is asphalt but has an adjoining concrete pad
 

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Discussion Starter #10
some pics from 7/14/19
setting up for the large right hander

"Her Majesty"

pushing ,maybe a bigger front sway bar ? cheaper than a 347:shrug:

Pedigree ,,84 GT350 vert

@dobrostang do his thing
 

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Boy that is some serious roll, I have no idea if its too much or too little! I'm trailbraking hard there trying to keep the front tires loaded. Maybe its time to bump to 1 1/8...
Looks like the tires themselves are nice and upright, no lean, you got something going right there.
 

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Discussion Starter #13
Boy that is some serious roll, I have no idea if its too much or too little! I'm trailbraking hard there trying to keep the front tires loaded. Maybe its time to bump to 1 1/8...
closest two I can find for a direct compare

 

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Fastback looked like it was accelerating where the notch was braking.

Fastback has a lot of body roll for sure and quite a bit of weight transfer towards the back. I'd think about some spring rate changes if you can. High rear spring weight would help. Shock tuning could band aid it.

where are you seeing push? Any pics of the fastback from the front while mid corner with even throttle?
 

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Fastback looked like it was accelerating where the notch was braking.

Fastback has a lot of body roll for sure and quite a bit of weight transfer towards the back. I'd think about some spring rate changes if you can. High rear spring weight would help. Shock tuning could band aid it.

where are you seeing push? Any pics of the fastback from the front while mid corner with even throttle?
You'd be surprised how stiff the springs are, I have .685 diameter "big block" springs, most people performance oriented folks are running 620s. Its not easy to compress the front end. In the back I have 5 1/2 leafs and the front half of the springs clamped solid. Really makes it fun braking deep into a corner, clamping the springs, there is no axle wrap. Opentracker turned me on to this trick. Plus I can do sweet burnouts. You'd think that would be rock hard but I think they are Grab a track, not the best metal so its stiff but not buckboard hard.

In the hard roll photo I came into the corner very hot, braked very hard and tuned in with the fronts just tiniest push but was hit the cones deeper than where I wanted to be, the photo was taken at the apex where the trail braking just ended. The second photo I'm transitioning to a throttle run into the sweeper. Think I'm just driving too hard...

I was running the red Koni's full rebound on up front and about 1/3 out back. I just dropped the fronts to half before this autocross, didn't really notice any difference. The end of the day I was running 42 lbs pressure up front and 24 lbs out back. I'm also running a Watts link set all the way up which seemed to help a little with giving me some twist on certain corners. 1" sway bar up front none out back. 1/2" Shortened A arms up front 1" shelby drop

It bites well on flat surfaces if I brake hard into the corner and trail to the apex but NO oversteer at all. There was this sweeper though and when my foot came off the brake and I crested the crown of the road, she pushed like a janitor's broom right off the line costing me seconds not fractions of seconds and probably a few $$$ of tire. I think I blew it coming in to hot for the crown. I'd like a little more oversteer just cause its more fun to drive.


Thoughts?
 

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Discussion Starter #16
Fastback looked like it was accelerating where the notch was braking.

Fastback has a lot of body roll for sure and quite a bit of weight transfer towards the back. I'd think about some spring rate changes if you can. High rear spring weight would help. Shock tuning could band aid it.

where are you seeing push? Any pics of the fastback from the front while mid corner with even throttle?
Looking at the above pics I can see how it looks like I'm on the brakes but nope ,I was on the go pedal well.
Both cars sitting still flat and level, Marks car is probably at least an inch lower in the rear than mine

Where as mine might be slightly lower in the front
 

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You'd be surprised how stiff the springs are, I have .685 diameter "big block" springs, most people performance oriented folks are running 620s. Its not easy to compress the front end. In the back I have 5 1/2 leafs and the front half of the springs clamped solid. Really makes it fun braking deep into a corner, clamping the springs, there is no axle wrap. Opentracker turned me on to this trick. Plus I can do sweet burnouts. You'd think that would be rock hard but I think they are Grab a track, not the best metal so its stiff but not buckboard hard.

In the hard roll photo I came into the corner very hot, braked very hard and tuned in with the fronts just tiniest push but was hit the cones deeper than where I wanted to be, the photo was taken at the apex where the trail braking just ended. The second photo I'm transitioning to a throttle run into the sweeper. Think I'm just driving too hard...

I was running the red Koni's full rebound on up front and about 1/3 out back. I just dropped the fronts to half before this autocross, didn't really notice any difference. The end of the day I was running 42 lbs pressure up front and 24 lbs out back. I'm also running a Watts link set all the way up which seemed to help a little with giving me some twist on certain corners. 1" sway bar up front none out back. 1/2" Shortened A arms up front 1" shelby drop

It bites well on flat surfaces if I brake hard into the corner and trail to the apex but NO oversteer at all. There was this sweeper though and when my foot came off the brake and I crested the crown of the road, she pushed like a janitor's broom right off the line costing me seconds not fractions of seconds and probably a few $$$ of tire. I think I blew it coming in to hot for the crown. I'd like a little more oversteer just cause its more fun to drive.


Thoughts?
First, I'm a better driver than I am a car setup guy. But I've driven a bunch of CAM-T cars and mid corner pushes that benefit from trail braking can be a variety of things. I come back to the basic concept that adding weight transfer to the front is helping the grip in a steady state then I like to add rear spring or take away front spring rate. Lowering front ride height or raising rear ride height can also help. Front alignment can help as well with more camber. Not sure how much you run. You aren't running a locker are you? What tires are you running 42 psi up front? Sounds high.

I'm not a Koni guy so I don't know how aggressive the shock curves are but a quick word on going full stiff on rebound. Usually people are dialing up the rebound in order to keep weight on that end of the car and slow down the weight transfer to the other end. Something that would help you when lifting off the brakes and going to steady state towards mid corner. The problem that I've happen is that when you go overly stiff on rebound instead of slowing the shock travel down and therefore weight transfer it's like locking the shock in place which results in the same feeling as instant weight transfer or a supper soft rebound setting.

Just some things to think about or try. I'm sure you have already tried different things and can eliminate some of those suggestions.
 

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First, I'm a better driver than I am a car setup guy. But I've driven a bunch of CAM-T cars and mid corner pushes that benefit from trail braking can be a variety of things. I come back to the basic concept that adding weight transfer to the front is helping the grip in a steady state then I like to add rear spring or take away front spring rate. Lowering front ride height or raising rear ride height can also help. Front alignment can help as well with more camber.

1.5 negative camber, 4.5 castor - 1/16" toe in

Not sure how much you run. You aren't running a locker are you?

No - I have limited slip

What tires are you running 42 psi up front? Sounds high.
Ill have to look when I get home, I don't remember
I'm not a Koni guy so I don't know how aggressive the shock curves are but a quick word on going full stiff on rebound. Usually people are dialing up the rebound in order to keep weight on that end of the car and slow down the weight transfer to the other end.
INTERESTING! Never thought of it that way but it makes sense

Something that would help you when lifting off the brakes and going to steady state towards mid corner. The problem that I've happen is that when you go overly stiff on rebound instead of slowing the shock travel down and therefore weight transfer it's like locking the shock in place which results in the same feeling as instant weight transfer or a supper soft rebound setting.

Right now, both red konis are set at about the middle in rebound

Just some things to think about or try. I'm sure you have already tried different things and can eliminate some of those suggestions.

Until this last autocross, I've only messed with tire pressures. THat said, this last one I backed off from almost full rebound to mid on the fronts. Can't say I noticed a lot of difference.



I'm looking at how much roll I have but get conflicting info on adding a 1 1/8 sway bar. One site says it will help, a person who always seems to have the right answer and runs Vintage Mustangs says less swaybar to hook the front...


I do have an adjustable rear swaybar on the shelf which I know will help but I always wondered if it gives you oversteer at the sacrifice of total traction. If I can get the fronts to hook better without detuning the rear seems like the total hook would would be higher but that could be me overthinking it, not working from experience or data.
 

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Have you done the Shelby mod or similar so that you get a negative camber curve instead of positive? -1.5* camber is the minimum I'd run for a frequent autocross car and that assuming it has a strong negative camber curve (something these cars don't start with). If you have the room feel free to try experimenting -2.0 or -2.5*

The larger front sway bar will reduce body roll. I don't know if it will help your front grip though. It might if you have excessive roll.

Adding a rear bar can balance the car but often at the cost of total grip as you suspect. I was chasing a push on my 68 Camaro and added a rear bar. It helped balance the car but I did lose noticeable rear grip. Ultimately, I didn't care for it.
 
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