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There may be a little yeller 914 out there. I've given up on getting the new engine together anytime soon. I've replaced the broken CV joint and am hooking up the 1911. This will be a long weekend. I'll be instructing at the AX school on Sat. (I know, blind leading the blind) and then the AX on Sunday. I want to try adding some ballast to the front and see if it will help get some heat in the tires up front. I think better grip in all the turns will outway the loss in accel in the straights. I'm thinking of making 3 runs with ballast and then remove it for the 4th run and see how the times compare.

About a month after I got my 914, some dude at a gas station told me to put a full sand bag where the spare tire goes if I wanted "it to handle well"

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Adding to overall weight for any reason (other than to make class) is way high on my "bad ideas" list.
Your AX car's suspension is, or should be, tuneable to cure handling ills. Leaning how to do this is part of the job.
That said, "road hugging weight" was part of Ford's promotion of the Pinto. Good luck.

I agree JP. I brought this topic up last year or so and you said the same thing. I've been mulling this over for a while and it's just something I need to try. If it works I may put some effort into relocating some stuff to get better wt distribution. As I drive to events, I need to keep some room available for race tires and all.

I've also hooked up the rear sway bar. That alone may be enough. I've got my front sway bar as soft as it will go and I don't want to go to a smaller one.

I just keep remembering that one AX last year where the temps were about 100F and the front was sticking nicely and the car actually had some oversteer. surprised the hell out of me. I would like to figure out how to get the front working better.

Adding weight is a great thing for an autocross car. Just ask anyone who runs against you in your class, they'll agree it's a great idea.

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Bill, when I still had my 914 and Brad was helping me sort it out, your car was the topic of much discussion. Correct me if I am wrong here but I believe that you played with the Ackerman on your car. Now assuming that you achieved a Ackerman setting that better allows the front tires to track their desired paths with a smaller slip angle, we concluded that while you may have less tire drag under this circumstance, your ability to generate heat in the front tires will be severely reduced. While this is all conjecture, and I do not know what your or stock Ackerman is. I do believe that if this setting were to be optimized in the pursuit of less drag, tire heat generation potential would be severely reduced in an AX situation. On a track where a larger percentage of heat generation comes from the rolling resistance of the tire, this may not show up very much but in a AX situation where the run times and speed are low, tire heat is largely achieved through the sliding of the tire surface on the pavement. If you arn't sliding or even just distorting the tires side wall as much as it would be at a higher slip angle, it was my conclusion that heating the fronts could be a major problem. This does not even take into account the other affects Ackerman has on the inside tire contact patch, which could also not be optimized and thus be contributing to the understeer issue.

Disclaimer- I do not have any hard evidence to support my beliefs so they should merely be considered as an intellectual puzzle or as my College buddies call it, a mental masturbation. I know that there are people on the forum that have studied this at much greater length than my self so I defer to them for validation of my theory. I am in no way implying that Bill didn't do his homework on this, it was just something that I have been thinking about and have not seen raised yet as a possible issue.

To my way of thinking you want the car set up as neutral as you can get it....that would be best in the majority of a course.....with the front bar set about half hard (or half soft if you prefer). Once you're there, tire pressures can make a difference in front rear balance (traction) or the AR bar can be moved in pressures won't do it.

To start on that road, you have to get the front to rear spring balance close to right.

A toe change would certainly add heat to the tires and reduce any understeer issues. Can make the car a little twitchy.. and tire hungry..

Evan: I added a bunch of ackerman. I tested my car and another and a stock 914 has no ackerman. Over the years I've tried to read as much as possible on suspension design. Carroll Smith went from believing in anti-ackerman to recommending extra ackerman.

If you think about it: imagine you're in a turn and the outside tire is running at its optimum slip angle and all is fantastic. Now think about the inside tire. If it hasn't turned to its optimum angle then it is fighting the outside tire and pushing it straight. (as a worse case it didn't turn at all) I think that having the inside tire turn more than optimum then it is trying to turn the car even more and if its too much then it will scrub and generate heat also. At least then it's trying to help the front tire instead of fighting it. Most people get the effects of extra ackerman by adding toe-out. As I drive my car to/from the AX I didn't want to run a ton of toe-out on the street. So I run the front end straight up and get the effects I want by adding ackerman. Plus the ackerman is a lot more than what you would get by adding toe out.

Then I started thinking about tires. Most of the modern cars out there now are pretty heavy. The tire mfrs have to design their tread compound to perform well on a wide variety of cars. If a car weighs 2500# now days, it's considered pretty light. Most stock cars are in the 3000# range. That's roughly 600# to 700# corner wt. My front corner wts are very close to 400# with me in the car and some fuel. I don't think I'm in the correct range for the tires. I need a softer compound up front. I haven't been able to find it. I've even considered running Hoosier wets up front thinking they would be softer, but the Hoosier guy said that the wets have a harder compound than the A6 and I wouldn't be happy with them.

So, I'm left with experimenting with adding some extra ballast to see if it helps with grip.


Grant: sand bags, just what I was thinking! I was going to leave a "spare" tire up front and add a couple sand bags. See what happens if I add about #100. It would be half the wt of a passenger and positioned right where I want it.

Bingo

Falkins worked very well on the lightweight cars but don't work very well on heavy cars. Same with the Toyo's. You have to find a tire that is happy on YOUR car at your weight.


B

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I don't have much room for wider wheels/tires. 7" seems to be the "spec" tire for the 205-50-15 for both Hoosier and Kumho. The tire looks good on the 7" rim. The sidewalls go straight up and the "tread" surface is very flat.

I think I'll play with ballast and rear sway bar for now.

Maybe I just need a co-driver for the 914.

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They're predicting a little rain on Friday, but Sat, Sun should be dry. It may even warm up some. But, you know Marina, never can tell what it's going to do. We'll be in the 3rd run group and work the first. We'll be out of there before lunch.

So what's the deal with UFO- I've never run with them. Looks like Saturday is a school (full) but Sunday is an autocross open to whoever? Show at 8 for run group 3? Hmm...

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Yes, definitely come on down! Would love to see your new car on Sunday!!! If you want to run for fun, you can run in any group you want, or run in class (SCCA based). They open registration again mid-day for run groups 5 & 6 if you don't like getting up early. Run groups 3 & 4 will most likely be the warmest.

I think I'll try and make it down. See if I can't get these street tires to work a little better. Might try higher pressures- maybe they will like mid 40s better than low 30s- they seem pretty hopeless so far...

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Yea, that's similar to what a bunch of the guys running the RE-11s are running them at. My first thought was that they would need less pressure on a lighter car, but it seems that might not be the case. We'll see...

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Another beautiful day at Marina! The UFO people really know how to manage the weather. We've been very blessed all winter. Got to see Pete's new Monster Tail-dragger. That car is awesome. Not sure where he ended up time wise at it is limited by the street rubber. Grant just barely broke into the 46.xxx and I was about half a second behind with a 47.4xx. I believe TTOD was about a 44.5. My grand experiment with ballast up front didn't seem to yield any results, at least as far as I could feel. We both got beat by a buddy in a CSP Miata! Gotta figure out how to get some heat into the tires!!!

Hey, it was nice to meet you in person! Yea, it ended being a very nice day after it warmed up... Your car looked very smooth and stuck- seems well behaved.

I think I ended up with a 47.1 after playing with the tire pressures from 35 through 48 psi trying to find something halfway decent. I didn't really- time to try some other tires. The RE050s just don't seem to like a light car. Fun day, though, lots of crazy tail slides, etc. And the monster is getting there:) I was able to run the whole course in first, but that was a little too much... Not that it wasn't fun

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I asked the guy in the CSP Miata what his secret was, as I had been beating him pretty regularly andhe hadn't been running very high up in the overall standings. His answer was "tires". He switched to Hankooks and really likes them. He says the first time out they felt terrible. The next month they went faster (he was 10 fastest overall) and this 3rd month they felt even faster. We'll have to wait for the results to come out to see where he finished up, but I'm pretty sure he's in the top 10 again.

I'm a little disappointed in the A6's. I set my pressures before every run and typically have to bleed off about 1 psi after each run. Today, I didn't have to bleed very much off the fronts at all. The right front stayed right where it started before the first run.

Anybody have any info/experience with the Hankooks Z214???

Hey Pete, when do you start your One Lap of America? Sounds like quite an ordeal. I hope you have some gearing that make all the hwy driving bearable. I'm getting to where I don't like driving my car on the street. It rides way too stiff and the engine has to rev too high to maintain normal hwy speeds.

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I believe it was Kumhos. that point is that he is getting the Hankooks to work very well on a light car.

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You're welcome Look at where my radiators are...

One Lap starts in six weeks- it's going to be busy getting it ready in time. I'm hoping Grant's right and the RE-11s work better than the RE-050As.

The car's loud on the street at the moment- we need to quiet it down and we'll still probably need to wear noise canceling headphones in order to get some sleep in the car. It's got 6 speeds, though, so it's probably around 3400 rpm at 85, which isn't too bad if we can quieten it down a bit...

In college I had a car with a very loud exhaust and a few hours of hwy driving would take its toll on the driver. You may find that a few HP lost to a good muffler would be offset by a driver that isn't exhausted.....no pun intended. The car sounded so sweet at the AX, but how did you feel when you got home? Then add a few hours to get to your next venue. As they say, just my $.02.

Yea we're going to quieten it down some. The car's not quite done yet, as you can tell... Glad it sounds good from the outside

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Got the results in the mail today! Grant was 11th OA with a 46.999 and Pete was 13th OA witha 47.138 and I was 16th OA witha 47.431.

TTOD was a 44.138 EM car listed as a Mazdat, I assume a rotary powered Datsun?