Davemk1

If you have the sump clearance it also allows for a lower center of gravity without resorting to lowering the suspension and messing up the geometry. I run 15's on the street and 13's while autocrossing. The 13's are also easier to carry with me to events. dave

If you need to run 17's then you are stuck with DOT tires as I recall. The Hoosier A6 and the Azenis 615 are the real choices. I see the Azenis are available in lots of sizes in 17's. I just looked at the Hoosiers and they also list lots of widths available in 17". Dave

The rubber compound is the same or very similar and the A6 generates more grip for some cars according to Hooiser. The downside is weight (the A6 is much heaver than a race slick) and the sidewalls of the A6 are made for the weight of sedans. So they can be too stiff for a Seven and cause them to skitter around. The A6 is a DOT tire that needs to pass the DOT tests (puncture resistance) and have a certain thread depth (which is why it has the two grooves). The race slick needs to hold air and that's about it. Dave

Do you have room to run 15's over whatever brakes you've got in there? Dave

Getting the power down won't be the issue. Turn in will be. You'll need to be patient with the power and resist the temptation to floor it to use all that HP you have only to push too deep into the next corner. With such short runs you'll barely get the rears warm and the fronts will be cold and understeer becomes the real issue. You can't count on tire temp being a benefit ever. Figure you'll be running on cold tires. Suspension tuning and geometry up front will trump power in autocross every time. So dial in your front numbers and do some basic checks for front tire temp (even temps across the width of the tire) to dial in air pressures and camber. All that said running the uber-soft Hoosiers is the ticket. I use the 25B's (13x8" all round) and they hook up very well even 5 seconds into a run when they are stone cold. Theoretically a narrower tire will heat up faster but there isn't a tire out there that will warm up in the first 10 seconds of a run so go as soft as you can and maximize the footprint and you can do very well. FWIW I get tire temps of about 110* front and 120* rear on a warm (80* ambient) day in my 1400lbs car/driver combo. Optimum temps for the Hooiser 25b are in the 140 range so I'm never there. But transitions are crisp and clean and the grip is very predictable. Have fun experimenting! dave

I'm a member of the SCCA and our local club has an online forum and lots of the folks there know me and have fun at my expense for driving a Seven in Montana. About a year ago I had battery troubles and wrote this entry on our club forum. I was recently reminded of it and thought you all might get a chuckle at my expense. Rejoice in the warmth of spring! Dave ---------------------------------------------------------------------- So let's say you have a Seven type car and it's in storage for the winter. You of course want to take it out a few times to get everything loosened up when the weather is good. Folks will look at you like you are from Mars but how's that different from any other time. So you go to your storage room and try to start the car. Battery almost dead and it won't start. No problem you are a smart lad and you brought jumper cables along. It starts right up and all is right with the world. So it's now time to drive. Where do you go? How bout the Honda dealer to see with they have a Fit on the lot? So you drive across town to the Honda dealer and pull in and instinctively turn the car off. You wonder right after shutting it off if that was a good move or not. Ahh....it'll be fine. You then walk around and look at the shiny cars (the Civic coupe looks very nice for 17K). OK........ so now it's time to head back to the storage locker. Get yourself in the Lil' car and drive it home right? No problem. But you turn the key and it turns over 1/2 turn and that's it. Hmmmm. Try again and the same thing. It's at this point that I developed the "how to" push start your own Seven by yourself - 1) push the car back and forth a bunch of times to get it lined up as best possible so that when you are pushing the car it won't run into a new row of Hondas. 2) remove door and steering wheel so you can get in the car quickly. 3) double check aim of car as you are about push it down a gentle slope with rows of new cars on each side sans steering wheel. 4) turn on ignition. 5) put car in neutral. 6) think about your order of events very carefully so that when you are running along side your own car without a steering wheel that you can jump in and get it all done in the right order. This is a very important step. 7) with #6 more or less clear in your mind push the car like a mad man down between the row of cars and jump in and accidentally hit your foot hard on the brake pedal making the car come to an instant halt nearly throwing you into the windshield as you aren't wearing the belt. 8) Turn off ignition to save what little battery is left and push the car back up the grade. 9) repeat........ push car down grade jump in, push in clutch, put in gear, let out clutch and blip throttle and nothing. You forgot to turn ignition back on. 10) push the car back up the grade. It's not a problem that it's cold out anymore as you are now plenty warm. Rejoice in the warmth. 11) TURN ON THE IGNITION! Push the car down the slope being careful to not run over your own foot (it's pretty close). Jump into the car, push in the clutch, place in gear, let out the clutch and blip the throttle until it catches and push the clutch back in so it doesn't stall. Too late, it stalled. 12) Turn off ignition, push the car back up the grade and rejoice in the warmth. 13) Turn on ignition, push like a mad man, clutch, gear, clutch, blip, clutch and it's running. Rejoice in the running. 14) Now with the car running you can relax. Put on your belt and drive it back to the storage locker. 15) Pull out of the Honda lot noticing that it's very windy and cold. Note that you left the door in the Honda lot and return for it. 16) Pull car up to the door and DO NOT TUN CAR OFF. Reach out of running car and pick up door and install. 17) Drive back in comfort and remove battery when you get back so you can buy a new one. There that was simple wasn't it? How to push start your own Seven. I hope you learned a lesson here. Dave

Do you know the caster setting you are stuck with? Dave

Is the caster adjustable? Lots of caster can be key as it allows you to run less camber (more caster means the the tires develop more camber as you turn the front wheels) and still get the front end to hook up. Lots of caster allows you to run minimal camber so you have more even tire wear and better braking yet still have the camber needed in a turn. So how much do you have and how much can you get? dave

I bought my Birkin from Mr. Brink and it was a good move - I'd buy from him again. dave

The understeer is surprising. Have you ever taken tire temps across the width of the tires in front? I'm wondering about your camber and toe. The only way I can get my Birkin to understeer badly is to completely overdrive it with lots of throttle and a stab of steering on turn entry. Otherwise it's neutral or oversteering. Dave

Corner weight scales. They are a bit spendy but 4 of us autocrossers went in on a set and it works out very well. Dave

My Birkin has 51% of the weight on the rear with my butt is in the seat and with a 1/2 tank of fuel. Fuel doesn't weight enough to change that in a big way in my case. A full tank would add about 30 pounds to the rear. I don't notice a difference in handling with changes in fuel load. I use my car for street and autocross and it's not like track racing where the change of fuel load happens during a run and one might feel the difference. Each autocross run feels different due to other stuff like temperature and fuel load doesn't change much during a day of crossing. I've never driven the car without my body weight in it and I'm not sure how I might get that to work Dave

It's funny how slow it looks when the camera is panned along keeping the car in the center. I'm hitting the limiter at one point in 2nd so it's not a really slow course. It's a fun lot to drive in as it's a bit slickery and the big HP guys have trouble putting it down. The sound is a DNA truck muffler with a 2 1/2" side exit set up. Glad you like it. Dave

What a surprise! I'm infamous. Yes that is me racing on the biggest lot in Bozeman MT. It's on the MSU campus here and the lot is small but fun. We live in a small town with small lots and most lots have little islands of green space in them that make them unusable. Race season here starts in one month and I've got work to do on the car. I'd better get busy. dave

Same exact thing I did with my Birkin. Works very well. dave

I for the most part agree. One issue I see is that Ford (and other US companies) have harkened backward to their glory days of the past to try to conjure up some enthusiast interest and sales. The new Mustang is an interesting styling exercise but it is HUGE compared to so many other "sports" cars available now. If driven them on a few occasions and can't image having much fun with one do to it's size regardless of what you are doing with it. The straight-line muscle car's time has come and gone and nothing can bring it back. My poorly made point is that while looking back to your better days might get a few old timers like me to want to spend their money it will take new designs and concepts to get younger folks to part with their money. Other companies have spent the time and the money to come up with new models that have created demand for them while Ford has looked back. Unless they look forward and adapt they will end up like Buick and Pontiac trying to sell cars to a shrinking supply of old guys. Like the old fat guy looking back on his glory days of high school football Ford is living in the past. It will take a serious change in their outlook and a brave move to get the enthusiast to look twice at Ford again. Dave

I converted my Birkin from the stock rear exit 2" exhaust to a 2 1/2" with a side exit. More power, less fumes and a good bit lighter. A win-win deal. I used a DNA stainless muffler and all stainless pipe. It works very well. dave

I have the Toyo T1R's on my Birkin and I like them very much. I have 195/45-15 on the front and 215/45-15's on the rear. They ride well, deal with heavy rain very nicely and they are quiet. The grip is fine for a street tire and the breakway is very controlled and I've not gotten in trouble with them at all even in spirited driving. The seem to be wearing well. I'd buy them again. dave

I've got a Birkin and I'd buy another one in a heartbeat. It has it's flaws like anything else but overall I like it very much. I bought mine together and used but think about buying another at some point in kit form so I can make every little thing just how I'd like it. FWIW I bought mine from Dick Brink in Texas and he was straight up and honest and I'd buy from him again. Here's his site - I think he's got some used Birkins now. http://www.texasmotorworks7.com/ Dave

FWIW I'm 6'4" and 185lbs and I fit in the Birkin very well..... now. I did have to make some changes to get myself to fit but they were pretty simple. My guess is if you are 6'2" or below you'd drop right in even with the stock seats. Dave

I might be up for coming down from Bozeman and running a day with a few folks. FWIW our SCCA club just posted it's schedule for the upcoming season. If you are close and want to run we'd love to have you. Date Host club event location April 18-19 Helena (tri-region) Helena May 3rd Ice Gardens Bozeman May 10th Helena (Missoula) Helena May 30-31 EVO & Autocross Helena June 7th Helena (Missoula) Helena June 13th MSU Bozeman June 20-21 Helena (Bozeman) Helena July 11th(12?) MSU Bozeman July 25(26?) MSU Bozeman August 1-2 Helena Divisional Helena August 15-16 Top Gun Helena Helena August 30 Ice Gardens Bozeman September 20th Ice Gardens Bozeman If you are in the area in July we are running two events right in town at Montana State University. A fun lot with a good turnout of about 30-40 folks driving all kinds of stuff. Figure a minimum of 6 runs. All the best, Dave

FWIW the three photos I posted were taken by me in Bozeman MT during spring and summer of 2008. If they are useful for the calendar please feel free to take them Dave

Did someone say snow? Very late spring 2008. Dave http://www.usa7s.com/aspnetforum/upload/1289198864_DSC_7713.jpghttp://www.usa7s.com/aspnetforum/upload/488695037_DSC_7732.jpg

My 1999 Birkin S3 on one of my favorite roads near my home this past summer. It was a very good summer. Dave http://www.usa7s.com/aspnetforum/upload/743544550_DSC_0141.jpg

I found a 10" Momo suede wheel on eBay a few years back for pretty cheap and it works very well. The thing I like about it is that it has no dish which in effect gives a longer reach and more arm room. A good thing considering I'm 6'5". The suede is a bit slick at times without gloves but has never been an issue on the street. I always use a suede glove when autocrossing and the tow together work very well. So if you want to fine tune your reach consider if the wheel is flat or has dish and how much dish. Dave