Need to be 3sec faster 84 3.2
 

Hi,
I don't post much, but I figured I'd reach out to you guys. I have a euro spec 84 911 I've been autocrossing. I am looking for winter projects and figuring out where to put my money. I currently just beat my 3.2 counterparts (somehow) and want to try to beat my friend and I need to deduct 3 seconds from my time (out of 75ish seconds).

I currently have some weight reduction (no back seats, no AC or blower). I have quickchange torsion bars, fairly light Corbeau seats and a harness bar/harnesses. The car also has a cheap cone filter intake, an unknown 4.5" single outlet exhaust, and 17x8, 17x9 twists wrapped in some old 225/45/17, 255/40/17 Potenza RE050's

My friends car is a 964 AWD Cabriolet with KW coils and some exhaust work with Potenza RE-71R's

My plan is to get myself RE-71R's of my same size, do some routine maintenance and splurge on some mods. I was thinking a Steve Wong chip, maybe a Tarrett front sway bar and maybe a throttle body enlargement? Any further weight reduction I can do? Oh, I also want to corner balance. I know there are a bunch of "get fast quick" threads (which I've read)....but really just looking to chit chat. Is three seconds possible?

https://c6.staticflickr.com/6/5715/2...7b710e6c_b.jpg

In order:

SW Chip
Brakes ( you did not mention brakes, believe it or not Good Brakes help reduce lap times )
Corner Balance

Sway bar would be good if #2 & 3 are taken care of first ( Actually #3 at the same time )

The first thing I'd do is buy a set of 15" Fuchs and put autocross tires on them. The wheel tire combo you have is slowing you down a bunch.

Talk to someone like Chuck at Elephant racing and give him a list of exactly what suspension components are on your car. My guess is that you have a bunch of parts that aren't optimum for each other. Make the changes he suggest and do a corner balance/alignment with settings suitable for autocrossing.

JR

Pro coaching. Fix the loose spacer behind the steering wheel first, then address car with a pro suspension and alignment evaluation and setup. Depending on the track, 3 seconds is possible. Chip and sways might be good for a few 10ths. Light weight 15" wheels and tires will make a significant difference in performance depending on your AX course. If you use 2nd gear only and are near redline in the fastest sections, smaller won't help much because you will be shifting into 3rd with smaller wheels.

I second the idea of getting a set of 7"/8" light weight 15" wheels. I saw a set of real fuchs in good condition with a crap paint job for $1100 in the for sale just last week. You will see the most bang for buck here in my opinion.

in order

improve the nut behind the wheel

15 inch wheels and tires- Buckley racing wheels 275 rear 245 front with hoosiers will give you much better grip, better braking and much more torque / better gear ratios.

2 hawk blue brake pads or similar. if you are running a oem pad you are leaving extra time on that track

3 more weight reduction, front and rear bumpers should shave off over 50 lbs Easley. light weight battery, remove spare tire..ect..ect.

4 aero- but this can get very complicated and expensive.

5 more suspension work.

I'm pretty set on the current wheels (at least the sizes)

Bumping up to Hoosiers would put me in a different class (and make me switch wheels at the track), and RE71R's are only attractive at 17" diameters. I'm really optimizing my grip I think with the 17's as I'm maxing the contact patch and available sizes offered from Bridgestone. Are there any decent tires available for 15's other than Hoosiers? Something with greater than 140 treadwear? In order to downsize wheels I'd have to go with 205's.....which seem far too puny to me.....even for my VW Scirocco I'm race prepping. (which is getting 15's though)

My brakes are factory and as you can tell from the picture they grab pretty well ;) but I was thinking about new rotors and some good pads. My buddy who does DE says the original brakes are sufficient even for him. Hawks sound good though....probably super beneficial

Has anyone gutted the bumpers? Mine are Euros so I imagine not filled with that American safety garbage.

A lightweight battery sounds like a good idea....any concern with taking even more weight out of the front?

FYI, this is my second year autocrossing and I am in the mix of (and just beat) some verrrry experienced people with the same car. I'm not a spring chicken.

I've got Toyo's on my 7/8" combo. They are all less expensive in 15" size. Proxes RA1.

This speaks volumes and is a wet dream to aftermarket bolt-on suppliers. $$$$

I would put corner balance at the top. Stock brakes are fine for autox, you only use them about 5 times, some of the others mentioned don't work until they get hot. Then weight reduction, cheaper than adding power. M&K muffler on my car is 10 lbs vs stock at 30 lbs. Tires, I've run Yoko Advan 205X50X15 for years both autox and mostly DE's but I couldn't believe how good they where at my first autox, they are about 140 tread wear. Then the rest is up to you, learn to be smooth, think what the tires/suspension are trying to do, transitions, turns, brakes and acceleration, smooth. Walk the course, look for anything that can upset the suspension, where to brake, trail brake and any straight section where you can get on the power. Good Luck

Don't be set on the wheels and tires, it's your biggest problem. What you have is way too heavy and way too tall. The 15's with lower profile tires are quite a bit lighter and will lower your effective gearing. You'll drop some serious time with this one change alone.

You have enough brakes. You don't need more. You could use lighter rotors, like they used prior to the 3.2 cars and gain a little benefit in acceleration.


The bumpers are essentially the same worldwide. The only differences were in the bumper mounts and the bumper trim (especially on the rear) so there's lots of weight to be saved if you install fiberglass bumpers on both ends.

Saving weight anywhere you can is a good idea. I don't know what changes you've made thus far, so I can't tell you where to go next.

Don't forget the suspension. I suspect it's far from optimum for autocrossing, so talk to an expert and change what he tells you to change.

2 years may seem like a lot of experience but in the autocross world, that makes you a newbie. Add up all the seat time you've done; you'll find it's not all that much. Because the runs are so short and you don't get all that many in a day, it takes years to get much experience. There are a few good books out there on the subject; they are worth a read.

JR

Seat time.
And your up against AWD. Good luck making up 3 seconds on a 75 second course.

Really?
 

Average ford F150 pickup has 2.7 Ecoboost V6 with 325 horsepower @375 torque. 3.5 Ecoboost V6 has 375 horsepower at 470 torque. Not even going to mention the V8. So why remove your back seats and AC? I've driven these powerful cars, on a straightaway, you will never see them again.

His tires and rims are 25 inches OD, same as the fuchs sizes you recommend. WHat do his rims weigh compared to what the Fuchs weigh? Are the Fuchs you recommend wider?

Your car is already faster than your friends 964 C4 Cabriolet, that is at least 400 punds heavier than the '84 Carrera. With the Euro spec engine, the additional 16Hp in the 964 is not enough to cope with the additional weight and the (big) negative impact of the front wheel drive.
Like others have said, it's seat time, seat time and seat time. And then 15" wheels with lower profile tires (23" OD), those will give you an 8% lower gear ratio compared to the normal (25" OD) wheel/tire combination. Try the Hankook R-S3 tires, they are great for AX!

Fuch 7 x 15 = 13.5 lbs
Fuch 8 x 15 = 14 lbs
I just picked up a set to refinish over winter. Look forward to putting some Perelli's on them and feeling the benefits I have been reading about.

I don't know exactly which wheels he has. I assume they are original Porsche. not copies, but who knows? I'd expect the difference to be around 8-10 pounds a wheel, or close to that, if they are original factory turbo wheels His tires could be anywhere from 2-4 pounds heavier than what I recommend, depending on which ones he might pick for the 15's.

My recommendations is for 7x15 & 8x15 Fuchs, so they would be narrower than what he has now.

The tires for the 15's would range in diameter from 22.5-23" for the fronts and 23.5-24" for the rears, again depending on his choice. So. they are significantly smaller than what he's running now.

JR

work on getting back on the gas earlier.

a good friend that was a top autoXr was telling me that was his key. I was asking him about later and harder braking and he said he does not do that, the key is getting on the gas as early as possible, also your line,. don't drive to the inner cone and look ahead.

big + on the 15's. I can see my 930 being slower with 18's than my brothers with 16's. just straight line accel,

I dunno what the hollow twist rims weigh. I am fairly certain you're right, though.

Give me a break. :rolleyes: