Stirrin the pot FRIDAY....

With my 3.2l project 914 I had planned on "goin' all the way" with respects to everything....and then I got thinking (always a dangerous moment)...

If I run 205 tires on a narrow body vs. 225 tires on a GT flare...how much do I really lose/gain?
245s are probably too wide without a V8... insomuch as you would be hard pressed to use the entire capibility of that size with a 4 or mild 6 (unless you are a pure race car)....and the increased steering effort on the street may not be an advantage....
So lets assume we have the 205 / 225 choice ....

You gain about 1/2 inch in tire width which is about 3/4 sq in per boot...
3 sq in total contact patch increase....
the rolling resistance of the 225 is greater...
and the drag from a wider body increases....
Roll cente stays about the same....
More weight (true it's unsprung weight, but you still have to turn it)...
It looks cool....

WAIT! Is this the only reason we flare a street 914? ...it looks cool?.....

Hmmmm...whaddya think?

Is there any good reason (other than aesthetics) to run a GT flare on a car that is not a pure race car?

It looks cool is a good enough reason for me.

if the creamsicle wasn't so special I'd flare it in a heartbeat.

Ping drgchapman, he's currently running a narrow body witha 3.2. I think the biggest tyre he can use is a 205, in AX competition he has major power oversteer issues if he's not judicious with throttle. Plus starts are a delicate matter, tyres spin for days.

IMHO if you want clean understated looks keep it narrow.
If however you want traction get flares & at least 245's. Even my little 2.2 will break tracion from standing starts with R compound 245's. However i can be ultra aggressive applying throttle mid corner.

Check this out...

http://www.914world.com/bbs2/index.php?sho...3&hl=flares

I like both looks.... I don't think that I would put the big flares on mine though.

Flare!

Check my signature.

The red 914 runs 205/50/16 "A" compound Hoosier DOT slicks on all four corners on 6" wheels. Not enough tire for a/x, period. So much throttle steer, she'll spin like a top and go up in smoke. Trevor has watched me run this car for a season and a half and has seen me come to grips with the lack of tires, mostly..... I basically have to settle for top 5 results. Tires are the limiting factor. 205's are all that will fit on my car, some guy posting 225's fit, not my car, no way.
The stock 3.2, mine has the Steve Wong chip which basically let's it rev a little higher, has a lot of torque. I added the LSD knowing the 205's would struggle with the torque. I'm having fun with the car in it's current state playing with the big boys, and my ego has come to grips with the fact I won't win anything.

On the street, I run 195/50/16 Kuhmo's on 6" boxter wheels. Good enough for the street, no problem. Problem with the car (read my right foot) is it is too damn fast. Hard to drive it on the street, it hits 100mph very quickly, I need to time it....... 0-60 has to be well under 5 secs. Be carefull, at least more careful than me!


All that said, I have a set factory steel flares in the garage. Someday I'll put 'em on.........to fit 245's on the rear and 225's on the front. I am certain that 225's are not enough for the rear. This car is much lighter than a 86 Carrera and needs more tire for the torque to bite.

For now, I enjoy the "sleeper" mode. Every event, someone comes up and asks about the car, compliments the whole package and just smiles. There are usually comments about the skinny little tires and how good the car goes.

Click to view attachment

Your contact patch will not increase. It will change dimensions but the overall area will be the same.

Flare

typicall engineer ... you think too much ...

that, plus a few false assumptions, and you just created yourself a nice "roadblock" ...

a few things:

- steering effort with wide tires. a myth, unless you try to turn them with the car sitting. as soon as it rolls, all will be fine.
i'm running 10" slicks and steering, even when going slow in the pits, is just fine.
you'll be able to steer 245 street tires with one finger ...

- 245 too wide without a v8. i ran 225 with my 1.7L. in fact, i ran the 10" slicks with my 1.7L.
the wider the track, the more contact patch, the better your cornering. regardless of engine size ...

- more drag due to wider body. yeah, but negligible. the 914 (narrow body) has a better CD than the 930. the GT flares won't add much ...


if you're interested in driving your 914 on the edge and hard cornering is something you enjoy, you *will* benefit from wider tires and a wider track.
regardless of engine size.
a bigger contact patch will also help you accelerate quicker as it provides more traction. same goes for negative acceleration (better stoppage is gud!)

if the above is not your cup of tea, a narrow body car will work just fine. i know of several cars that push anywhere from 250 HP to 400 HP on 205 street tires in a narrow-body chassis.
they all are a handful to drive ...

Andy

Well, I'm no engineer....but I did say when I think....it's dangerous....and sometimes hurts my brain...
As for steering effort...I disagree...ever parallel park your 914 with 245s all around?
Bigger is not always better....larger contact patch =better cornering yes, but you have to turn those big boots...how much time are you at your limit of adhesion in a corner vs the rest of a lap?
Taller wider tires are bigger and require more power to turn them....Try riding your 10 speed bike all the time in 10th gear....you'd do better if you had more power....
unless you have an abundance if power (can break 'em away in 2nd gear+ type power) your acceleration is slower. I submit your 1.7 cornered wonderfully but was too slow everywhere else...oversize tires also carry more inertia as the rotating mass is larger...

Widebody pushes more air, the faster you go the harder it gets....put your hand out a window at speed like we did as kids....see!...the 930 has some power to push through this...at 95 or so HP a small 4 banger is taxed heavily....we noticed a huge difference when widening my VW GTI race car....flares/225 vs 205/stock was 1/2 to 3/4 sec slower per lap at mosport....about the same as a 180 pound weight penalty.

A narrowbody 300hp car on street tires will be easy to lose control of....but many 914 six conversions are between 2.0 (S@170HP)...and my plan of a 3.2 (@207 HP). The main question is at what power is a 225 wide R compound tire overpowered? My 72 911 S (2300lbs@190) was not outperforming 215 SO-3 street tires and it was very quick....I'm sure 205 R compounds would have worked perfect....

I am new to 914s but not Porsches or racing and auto X....but after all this I'm really just stirring the pot.....BTW I have been planning 245s and flares...mostly because I have retired from racing and don't want to be at the edge of preformance all the time....and they look cool!

Cheers....

Anybody else?

yes. i have. like i said, steering is no problem ...
as for the track comment on steering, i either corner hard or i go in a straight line inbetween corners. there's not much else.

maybe my arms are just bigger than yours ...

but seriously, i never felt like steering was hard or needed any extra effort.
Andy

PS: for the street, i have sticky hoosier's, 245 front, 315 rear. for the track, i have 9" (patch is actually 10") goodyear slicks ...

PPS: my 1.7L with GT flares and slicks was about 1-2 seconds off the fast 2.0L cars. fast enough to scare myself more than once.

PPPS: i know you don't like what i have to say and of course, it's just my very personal experience, which seems to vary greatly from your own.
it's all good and i shut up now ...

Andy.....I like what everyone has to say....and I respect your opinions.
Different opinions are what keeps life interesting...I enjoy debate...I think others like to read it too...

All I'm saying is if you used a G meter to graph a lap and looked at the total time you were at max cornering vs. the amount of time you were accelerating/decelerating or not at max cornering there is an argument to set a car up differently...a racers trade off...It depends on what the driver is comfortable with, the track, the competition etc...

My stock 1.8 8v GTI used to kick all the 2.0 16v GTI, GTXs by more than a few seconds a lap ...and I could lap them within anout 45 min at Mosport....I learned alot about set up and suspension on these cars as I did not have the $$$ to buy power...But I'm new to teeners and have never worked with mid engine RWD cars....so the experience of others is a great thing....I just have to reconcile with my theories a bit....then do some testing...I believe one of the reasons I was so successful at racing was I did not just do what everyone else did....and I did research....bench racin' is fun...

Cheers,

Sean