wheels, tires, and flares Options

[ottox914]

While building the next generation turbo motor for the 914, thoughts turn to putting the power down. I'm currently autocrossing with 205-50-15's on 7" wide Keizer rims, with a slight pull of the rear fender, the return lip cut off, and some spacers to keep things from rubbing on the inside. Puts about 8.3" on the ground for the 710's I'm running currently. I'm expecting around 200 whp, with a class min wt for the car of 2150 or so. I don't see a need to convert to 5 lug, as I have some nice panasports for street driving that I like, and the bigger brakes wouldn't buy me that much in a 60 second autocross. On a road course, yup, bigger brakes better, for autocross, lets keep it light. Car runs in what used to be SM2, is now SSM. Here's the kicker- even with 4 season old 205's, in 150+ car grids, with several national jacket winners and a dozen or so trophy winners, I can put the car in the top 20, top 10 if I have a great day. So how much more tire do I really need to have fun locally, which is what the intent of the car is. I know it will never be the perfect weapon for a season of divisional/national events in SSM.

Here are some options I'm considering:

- run 225-50-15's on the same 7" rims, do a little metal pounding/pulling to keep a basically stock looking fender profile. This would add about an inch of rubber on the road from the 205's, and be the cheepest solution, other than just staying with the 205's

- run 245-50-16's, which would require new rims in a 16 x 8 size, 4x130 bolt pattern. Diamond racing makes a 20# rim for $150 that would work, (but is a little porky) has a 4 1/2 back space, should fit under a standard GT flare, but this means more $$$, rims, FG flares, install, in addition to paint. It only adds about 1.5" from the 205 size contact patch, only 1/2" from the 225's. I don't expect I could get all that much for my Keizers, and new ones would be what, 1200 to 1500 or so? Thats alot of green.

- run the hoosier 275-35-15's, which like a 9.5" rim. I could get new hoops for the keizers, and keep the inside hoop and hub, which would keep the correct back space and bolt pattern for the car, would still need flares and paint. This tire puts 10.8" on the ground, approx. 2.5" up from the current 205's. Haven't checked lately, but don't think I can tub the car in SSM, although in XP that would be allowed.

Anyone running the 275-35-15 on a 914, or anything similar in a tire/rim/flare combo? Can it be done w/out making the car stupid wide, which of course would not be the best for slithering thru a slalom? Up north here in WI, the guys running slicks have problems for 1/2 the season- it just is so hard to get even the softest of them up to temp unless we have hot sun and 90 degrees out, so I would plan to stick with the DOT "R" rubber.

Thoughts?

[ottox914]

Some follow up- yes, 4 "seasons" = 4 yrs. I know I'm WAY overdue for new skins, but the old ones still seem to have a little life in them, and more time/money has been directed to the turbo project. I suspect that even with newer 205's the car would be much faster, even though I properly store the tires each winter.

Some tire and wheel info:

205.50.15, 22.9 diameter, 5.5-7.5 rim width
225-50-15, 23.8 diameter, 7-8.5 rim width
245-45-16, 24.6 diameter, 7.5-9 rim width
275-35-15, 23.0 diameter, 9-11 rim width

I'm expecting around 200/200 for whp and wtq, we'll see what I get. I'm going with a moderate amount of boost, keeping some compression and timing, and a smaller turbo with a big intercooler to make this a fat TQ motor, not a 9000rpm honda ricer turbo, with 25 psi boost and 7.5:1 cr, and no power below 6000 rpm. I'm shooting to give my friend and his elise a run for the money, and his car is around 2000lbs and 190 chp.

Wheel size- yes, width DOES matter that much. I had some 205's initially on factory Fuchs rims, pinch city. Just moving them onto the 7" Keizers really woke the tires up, so I can see what Josh2 is saying about going to an 8" rim for the 225's. On the 7" rims, the 205's look like steamrollers, and they're only 205's.

As my wife does like a ride in the car from time to time, a world beating autocross car in not in the cards for me, until the next wife comes along. Not a likely event. So. No gutting the car, no cage, it will remain a 75% car. Nancy has 3 rules for car prep, shorter than the scca bible, but just as restrictive: Has to look like a 914 when I'm done. Has to run on pump gas we can get anywhere. Can't morph into something that needs a truck and trailer to get to and from events.

Josh2, what rims are you running? I like the idea of keeping the car looking "mostly" stock, not incurring the expense of flares, install, paint, keeping the car narrow, and maybe just re-building my Keizers to 8" and rolling with the 225's. Add or link up a bunch of pics of the wheel openings. So you didn't need to modify the front at all for the 225/8" combo? I'd love more pics, close ups if possible, of the front and back of your set up, as this is the direction I'm leaning. If you have any pics of the pulling party to mangle out your fenders to fit, that'd be cool to see too. If its to much to add or link to, PM me and I'll send you an email addy to send the pics to.

While those 275's would be tempting, I'm not sure the added width would be worth it for a 75% car, with no cage or additional bracing. Now for that magical 100% car we'd all build if/when our ship comes in, well...

(I suspect that when my ship does come in, my dock will be rotted away, and it'll have to pass me by and end up at some other guys place.)

[jhadler]

Some follow up- yes, 4 "seasons" = 4 yrs. I know I'm WAY overdue for new skins, but the old ones still seem to have a little life in them, and more time/money has been directed to the turbo project. I suspect that even with newer 205's the car would be much faster, even though I properly store the tires each winter.

Doesn't matter that you store them properly (well, okay. It matter a -little-). What -does- matter is the number of heat cycles those tires have gone through. Most 914 autoxers will turn DOT R tires to rocks long before cord is showing. With 4 seasons of regular autoxing on those tires, they're now rocks. Little doubt.

Josh2, what rims are you running?

Two sets of rims right now. Keizer and Diamond. Both 15x8 with just under 5" backspacing.

I like the idea of keeping the car looking "mostly" stock, not incurring the expense of flares, install, paint, keeping the car narrow, and maybe just re-building my Keizers to 8" and rolling with the 225's. Add or link up a bunch of pics of the wheel openings. So you didn't need to modify the front at all for the 225/8" combo?

Fronts were untouched. The rears I used the "fenderizer", a rounded hardwood 2x4. Considerably more aggressive than the baseball bat technique, but it got me around 1-1/2". Paint cracked and little, and the metal's not perfectly smooth, but it got the job done. More time and effort, could have done it alot nicer.

I'd love more pics, close ups if possible, of the front and back of your set up, as this is the direction I'm leaning.

Here's what I've got right now. I can try and get you some more in a couple days.




It's a tight fit to be sure. Fronts rub only at full lock.

-Josh2

[ottox914]

JP: don't know how I missed the 23" on the 275's, I corrected the prior post.


Josh2-

Agreed that my current tires, no matter how carefully cared for, are now rocks.

Keizer and Diamond. Drys and wets? Which to you prefer, and why? I was surfing the Diamond site, they look to have a 15 x 8 rim for $110 or so, coming in at 16 lbs. I always thought the Diamond/Circle racing steel wheels were tanks, but for anything less than a million dollars per wheel for a 4bolt pattern rim, that doesn't sound half bad. I'll need to look into the cost of updating my Keizers to 8" also.

"Fenderizer". OK then, that looks like one solution. Did the gaps at the door or trunk suffer when the fender was moved? I tried something similar, but less aggressive on my fenders, some pvc pipe, and jacking the air pressure way up in the tires, it was a kinder, gentler pull, but not enough to fit 8" rims. Going to be in Rice Lake, WI anytime soon? Bring the big tool, I'll go out for the beer and pizza, you have at the fenders while I'm gone and I won't have to watch then...

Pics- thanks, and of course, more would be welcome. Close ups if you can. How much is your car lowered? Hard to tell in the pics you added, but the back looks a little higher relative to the front. Could be your preferred set up, braking and wt. transfer, or does the back need to be set like that to clear the tires?


Phoenix: I'm thinking 225 all around, easier to rotate tires, 4 matching rims, all that stuff. Sure, if the motor comes together and makes crazy power, I might be wanting for more tire in the back, but we all need to keep in mind, this is intended to be a still streetable weekend toy for me to tinker on and toss money at, not a full tilt rule the world autocrosser, so if I have a little more HP than handling, I can dial the boost back a little, exercise rt foot restraint, or figure out how to fit the 275's on at that time. Our early and late season events can see 50 degree high temps, so I certainly don't want to go TO big on a tire for a local event car. Agree w/you on that for sure.

Like the sound of that 225.45 tire. Its about the same size as my current 205.50's. I recall way back when the AVS intermediate was the tire to have, I got some 195.50's, down from the 205.50's I had been running. Even that small change made a big difference in how the car would jump out of corners. Made for some pretty high revs on the highway at 80 mph, but was hard off the line and out of the corners. When I had burned those up, and went back to 205.50's, I thought the car was broke, it seemed so much slower off the line. I checked and bled the brakes several times thinking one was dragging...


More thoughts: If the 225.45's on 8" rims are a tight fit, how about this for a plan. Order up some Diamond rims in a 15 x 8, 4 1/2 back space, sell the keizers, add some flares, and a few spacers to widen the tires to fit the max width available by the flares. This does concern me as I don't want to fatten the car up to much and take away some of the slalom-abilty it now enjoys. And the flares would cost a little more for materials and labor than the "fenderizer"...