Any AutoX guys in here?

CarFreakGT said:

Why no rear bar? And, how do you like that Trac-Loc for Auto-X? I've read so many different opinions RE: rear diffs it's hard to know what to make of it. I'd love to do some auto-x in my 68 coupe in the future.

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I don't have a rear bar because with my previous setup it was REALLY loose with one and still loose without one. My front springs were a mess. I put the car together years ago and I was shipped the wrong springs. I ordered the '620s', but I think I really go cut down stock springs. I was 18 and didn't call to return them. Those soft front springs combined with the 5-leaf rears made for a loose car.

I may find I need a rear bar, but I also hope to take the car to a few Solo Trials and track days this year as well. I would prefer not to have a loose setup at higher speeds.

My goal is to find a setup that will work with a 1" front bar for autocross that will tighten up nicely for track days with the 1-1/8" bar.

As for the Traction-Loc, I don't know yet. I'm going to be installing it for the first time in the next few weeks. It's no-doubt a compromise, but I can't get a T2R for an 8" or 9" axle. I considered PowerTrax, but it got so many reviews of bad mid-corner characteristics that I decided to stay away. I found a Traction-Loc rebuilder that will make me one with 4-pinions and a higher pre-load clutch pack. He also says that some of the problem of T-Locs going soft quickly can be attributed to new steel plates being used. What he told me was that if you re-use the steel plates and then set them up with 180 ft-lbs of break-away torque, they break in to where all new T-locs start out (~120 IIRC). That's what I'm having him build.

We'll see how it works in May. Maybe I'll end up with an 8.8" swap to get the T2R. My wife had a 4th gen T/A Firehawk with a T2R and it was awesome.

I ran a lot of gear/speed numbers and I'm going to stay with the 3.00:1 gear ratio. It's terrible on the street with the T5, but it will give me a 2nd gear top end in the high 60's with a 23" tire. If I put the rev limiter at 6,000 rpm, it goes to about 70 mph. We have a couple of high-speed Solo Trials coming up this year where that could come in handy.

CarFreakGT said:

Sorry for the OT and potentially dumb question, but why no rear bar? And, how do you like that Trac-Loc for Auto-X? I've read so many different opinions RE: rear diffs it's hard to know what to make of it. I'd love to do some auto-x in my 68 coupe in the future.

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Leaf spring cars have a lot of rear roll stiffness from the leaf springs. Whether or not you will need a rear bar depends on a lot of factors including what tires and springs you're running, the weight and weight balance of your car, even your driving style, etc. The best way is to figure out what works for your car and you, like Applejack has.

If you were doing all low speed stuff, oversteer might be useful to help get you around corners. High speed oversteer is super dangerous, though.

I have a few questions... would the rear sway bar help more if the car was rear heavy? (IE. running a 65 comet wagon...) Can the rear leaf springs be custom made? The wagons had specific springs that were longer than the sedans or mustangs and far as I can tell, always had a stupid helper shock. When it comes to front springs, the wagons always had the lowest spring rates. Do you think this is because of the added rear weight, or just because it was the least sporty car of the lineup and engineers were going for best ride quality? Id like to set my wagon up so it can turn without scraping the chrome off the doorhandles, rather than straight lines (who knows if itll ever happen) so I can take it to Waterford racetrack someday.

If you were doing all low speed stuff, oversteer might be useful to help get you around corners. High speed oversteer is super dangerous, though

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you ever watch any video's of the old T/A races? those guys are throwing those cars sideways at very high speeds, i saw one of Parnelli passing 3 other cars in a corner on the inside and the grass sideways all the way through corner and back onto the track. all i could think about was PJ saying "yeah, i meant to do that. that's my super secret driving technique I learned driving Baja" or something like that.

My '68 has one coil cut from stockers, 1" sway, KYB GR-2 low pressure shocks, new stock rear leaves, 3/4" sway, KYB GR-2s, 1" lowering blocks. Corners fairly flat while still reasonably comfortable on the drive to/from the event. Running in Vintage class, doing well, but little competition in that class.

All of the above posts provide good suggestions. Here is my recommendation, assuming a stock early model Mustang, in order of what I would do.

1. Monty Carlo Bar and Export Brace - These are cheap, easy modifications that can be done in an afternoon and will box in the engine compartment and help to stiffen up the front end.

2. Upgrade to a 1" Front Sway Bar - another cheap, easy mod, that makes a noticable difference.

3. Upgrade your shocks, front and rear - KYB's if your on a budget, otherwise get Edelbrock IAS or Koni. Here is no place to save money, buy the best that you can afford.

4. 620 Front Springs and the Shelby drop - Upgrade to some aftermarket Upper Control Arms if your budget allows, either OpenTracker, Global West or TCP and increase the Shelby drop to 1-3/4" (recommended). The springs are cheap and the drop is free.

5. Adjust your rear ride height with some lowering blocks to match your new front end - cheap, almost free.

6. Now get some quality tires. If you don't already have them, get at least some 15" wheels, 225/50/15's will make a great tire. If you want and can afford, go ahead and go for some 17" with 235/40/17 front and 255/40/17 rear. Good quality tires are the biggest improvement that you can make to handling and stopping power of your car.

7. Add some subframe connectors - This is a crucial step in stiffing up the unibody chassis of a Mustang and will really help in the handling of the back end of the car.

8. Now is the time to upgrade your rear springs - I suggest 4.5, mid-eye leaf springs (you can fine adjust the mid-eyes with lowering blocks if you need). Also, add a quality shackle kit at this time to help control difflection.

The above recommendations will get your car set up pretty well and if you get into it further, consider:

Front Suspension
- Roller Bearing Lower Control Arms (OpenTracker, Global West or TCP)
- Adjustable Strut Rods ( StreetOrTrack, Global West or TCP)
- Roller Spring Perchs (OpenTracker)

Rear Suspension
- Maier Panhard Bar
- Traction Master underrider traction bars (upgraded with AFCO Springrods)

Good luck and keep us posted,
Tim

Great post...

Great post Tim. I had to copy that one into Word for my 'to do' files. Thanks.

I love this forum! Great advice everywhere you look!

65 fastback---
What is the story with

- Traction Master underrider traction bars (upgraded with AFCO Springrods) ?

I did a search on what AFCO Spring rods are, but what kind of spring rate do you recommend? How would you describe the change in the way the car drives? Sounds like it would smooth out some of the stiffness the underrider bars add. Pros? Cons? What's the skinny? This is the first I've heard of this.

S-Car-Go said:

65 fastback---
What is the story with

- Traction Master underrider traction bars (upgraded with AFCO Springrods) ?

I did a search on what AFCO Spring rods are, but what kind of spring rate do you recommend? How would you describe the change in the way the car drives? Sounds like it would smooth out some of the stiffness the underrider bars add. Pros? Cons? What's the skinny? This is the first I've heard of this.

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S-Car,

That's what the guys at CobraAutomotive are doing - http://www.cobraautomotive.com/Handling.htm - Down load their PDF catalog and check out the Rear Suspension Page (page 9). You replace the fixed bar of the Traction Masters with the spring rod. It is supposed to smooth out the rear suspension by eliminating bind and allowing the suspension to act more independently (side to side).

If you already have the Traction Masters, you can purchase the spring rods direct from AFCO - http://www.secureperformanceorder.c...D=14&ClassID=186&SubclassID=887&ProductID=756 - CobraAutomotive uses the 900# spring rate with an 11 tube, the mounting points are 24" center to center with 5/8" mounting bolts.

I still have my original Traction Masters on, but will hopefully swap in the spring rods before my first open track event this Spring. I'll report back after I have actually installed them and driven with them.

Tim

Where are you located? Certain parts of the country has a lot more classic mustangs running than other parts. If you're in the CENDIV, you might be in luck and be able to talk to some of the CP guys up there. Same goes for California. While some of what they'll recommend is probably beyond what you want to do, they all started somewhere.

I've run a lot in my '67 Mustang, but have spent the last 2 years in CP in a '79 Camaro (I'm a traitor!!) and done reasonably well at the National level.

Anyways. Decide how far you want to take it first. One of the things you see most often in Autocrossing (at least when you start changing parts) is that people tend to replace parts often trying to find the right combination. If you want to just have fun, it makes things a lot easier, but if you're trying to be really competitive, pick a class then follow the rules. I imagine most classic Mustang guys will go for SM or CP.

The Maier Racing parts are supposed to be pretty good. I worked a corner at the '03 Nationals with Mike and got to pick his brain a lot on their parts. They have a customer who has a '68 Fastback that runs in ESP that supposedly works pretty well. One universal thing I have discovered (and he also agreed with) is to NOT run Traction Masters, or any type of "traction bar". They'll cause the rear springs to bind up and be unpredictable at the limit. My '67 got a lot more controllable and faster once I took mine off.

My suggestion is to do some of the lower "buck" mods to get it to a point where it is at least reasonably fun to drive and then focus on getting as much seat time as possible. Sure throwing parts at it is fun and will make you faster, you'll get much faster with more seat time.

All great suggestions... here's one that I didn't see offered.

IF you have an automatic...... swap in a manual. I autocrossed my 67 with both and what a difference the gearing and fun factor can be.

It's also notable that most autox courses are set up for 2nd gear runs. I don't recall ever needing to grab third gear... and certainly never needed to get back down to first. With the original C4 I had... it sucked a few times because I was caught in the middle of needing first and second.

Fyi... I was running 3.80 gears in both instances.

Do the swap... best mod ever..... and then everything else mentioned above of course..