Grassroots Motorsports magazine, Dec. issue has 914 brake tech article Options

[SP9146]

I don't usually read this magazine but saw on the cover a mention of the 914 article so I bought it. Excellent explanation of the upgrades to BMW front calipers, etc.

This was actually one of the last articles in a series about their 914 project car. Has anyone read any of the articles, are they worth trying to find?

Pete

[brant]

JP,

I certainly don't consider myself an expert by any means... but here is a few observations I've had over the years..

I hope this doesn't come off as condensending or angry.. I'll just try and explain my own thoughts about the momentum question.

my old car had big brakes and vented rotors front and rear... The fast guy in my class had stock brakes and could out brake me into the corners..

After years of observation, ride alongs, and lots of track time... I learned that he wasn't so much out braking me or waiting later.. he just wasn't braking at all really.

Now this is certainly not the case on every corner, but it is true on some of the fast and some of the slow corners... for example:

pueblo corner 1 (I know this means nothing to you) is a 1/2 mile straight away, and then a 180degree 90mph corner. I used to try and stay on the throttle until I saw my braking point.. then I would slam onto the brakes and turn in. My buddy who I'm referrencing would close up on me during the turn in like mad. NOW, I've learned..... this is a trail braking corner. Instead of slamming on the brakes and dragging the car from 120mph down to 90mph and turning..... I turn at 120 and then trail brake down to the apex.. I can catch 5 car lengths on people in this corner just between the turn in point and the apex. Its an entirely differnt line on the turn in to make it work. I still am about 90mph at the apex, but most of the speed is being scrubbed by the turning of the car and the (holy cow did he say that:) LOCKED DIFF, plus a little bit of dragging of the brakes... When I do this, I'm not pushing very hard on the brake pedal and its more of a dragging action than a braking action.

Thats a fast corner, here is my experience in a mid speed corner. Take corner 10 at pueblo. Its a 90degree right hander, big wide, and about 60mph. I used to go up to it.. brake and down shift to 3rd then gas it at the apex and start the eternal wait down the straight away before the above mentioned corner 1. NOW, I leave the car in 4th, coast a little bit at the turn in, and then coast towards the apex while scrubbing a little bit of speed on the turn in... NO brakes used... then ease into the gas and start the straight away.

I used to watch cars go through lots of different corners and not use their brakes.. (or not light their brake lights)... I've learned that I had to change my lines/turn ins/ and corner style to make this work for me.

Slow corner: I brake.... I also scrub some of the speed at turn in with the car. I've never over heated those vented rotors... however the same fast guy I keep referring too (dale tutey by the way). I don't think he has ever overheated his stock rotors either. I do know that he has simple dryer duct tubing dumping air into the front leading edge of his caliper....

I'm not going to claim to know what your 210hp motor would be like at the end of a straight away. I'm also not going to have any clue what brad's old tube frame car was like at the end of a straight away. I'm sure that hp changes things a bit, on the other hand the fellas I know that run 1900lbs, and twin plug 3.3 electromotive engines... don't seem to be on their brakes that long, and still run my same trail braking line in that big corner 1.

I think that my experience on the track with a 914 has taught me that the trick to going fast is not using the brakes.... I have tried faster and faster motors with more hp, and always was disappointed that I would hardly pick up any lap time... then I feel like I came to realize that the lap time would come down by focussing on this use of brakes more than any other aspect of the driving..

Wow, I didn't know I could write a whole book...
have a good day all
brant