Today was my first track day with the Needswings dual CAI and a super cooler and it was in the upper 90's ambient temperature. First the good news. On the back straight they were worth 8 mph. On the front straight I saw a top speed of 127 mph. My IAT's ranged from 118º at the start to 172º at the hottest moment. With the new cooler, my engine coolant temperatures maxed out 10º higher than before at 235º. During the 20 minute full out session the IAT's varied from 138º to 172º and on the cool down lap came down to 118º. The IAT's remain around 15 to 20º above ambient temperature during normal driving. Now for the bad news. With the added mph I cooked the brakes. About 8 minutes into my run after braking from 127 mph to 46 mph (stopped fine) the next turn was tricky because I had almost no brakes. Through the esses to the next braking zone they came back and were fine until returning the the 127 to 46 braking zone. From that moment on I had the same problem. The brakes stopped pretty good but the next turn they were gone, and then they came back for the rest of the lap and worked fine. I'll be looking at them closely tomorrow.

On a side note, the Porsches and Subaru's can't pull on me in the straights now. As a matter of fact, I can close in. But they eat my lunch under braking and in a high speed ess section. My car has spun on me twice in the same spot. I think it has to do with the progressive nature of the Eibachs but cant' be sure. The front of the car is stable, its the back that is unpredictable under certain conditions.

I hope this is helpful information to someone. I'm starting a quest for more cooling and better brakes.

Les

 

it might have been a new learning event for you withy the new intake but you sound like you had fun. next week you will pull them more have fun and go get'm jim

 

Oh, I had a blast! I'm still worried about my IAT's. I don't have any logs with the IAT's from before changing the H/E. But there's no doubt that it's pulling harder than before even at 172º. I'd sure like to get the car running cooler on the track, both ECT's and IAT's. I'll try pulling the pan under the motor to see if it helps or hurts. It's just hot, hot, hot lately in Puerto Rico.

Les

 

Look up some of Jane's threads..... I think she went to a big brake kit on her racer....

 

She has the Stoptech BBK with Carbotech pads. I've been changing things one step at a time and only when necessary. (great for learning the sport, what works, etc.) It now seems wise to jump ahead a few steps to the BBK.

I'm lowering my starting tire pressures next time in the rear tires. I may be placing the blame on the Eibachs for the loose rear prematurely. Starting pressures were 26 psi front and 29 rear. My hot pressures are 32 front and 34 rear. The tires are wearing evenly. I think Jane's hot pressures are 32 front and rear. I'll search and if I can't find them, I'll ask.

Any comments on the IAT's? Should they be cooler based on the conditions?

Les

 

I too got worried about my brakes. They were so hot that I could smell them doing laps at Miiller Motor Park (UT). So next day I upgrated rotors, the fluid and bought better pads (rotex gold).

 

Hi Les:

First, what's IAT and why is that important? I don't know so I'm going to ask.

Secondly, road racers will have to upgrade to bigger and better brakes. As you know, we put the Stoptech on the front (no spacers with road racing, so you'll have to cautiously file down the outside of the calipers) and we are using the Carbotechs brake pads. This is an awesome setup. To get ready for the season, my racing mechanic looked at my Carbotech pads. I did go through a set this past year, but they lasted me all year. This year, he put Carbotech in front and also in the back. We have metal brake lines on and are using Motol 600. I NEVER smell my brakes, just everyone elses. The first thing I do when I'm done racing is to check for smelly brakes and check my tire pressures coming off the track. To get the best stick with the sport cups, I want my hot temps to be between 30-32. So, I start around 25-26 PSI; no more unless it is really cold out. So yes, let the air out of your back tires and you'll find great stick and better control. Sorry to say, but Rotex are probably good street brakes with little dust, but won't make it at the track, especially serious hard road racing.

Third: I'm having issues with the rear wheel bearings. The right have been replaced, and the left will be replaced tomorrow. So, 3 years on these bearings, as I understand it, is pretty good. You'll notice vibration/grinding noise when you turn to the affected side which will go away when you straighten the wheel. So keep this in mind when you are running hard and start to hear noise and feel unusul vibrations. I now think I'll have my bearings removed, checked and cleaned every year before racing season. I'm getting a little tired of these problems that start to creep up during the race day that ruin my seat time. I will get better at asking my mechanics to look at certain things before race day.

Now, I'm thinking about a Euro tune. What will this do to the car in regards to temp and work on the engine? Or will the tune just make the car do what it was originally intended to do as an AMG Mercedes which is go fast.

I was at Nashville this past weeekend. This was my first oval track with an infield course. The transitions on and off this track are not easy. In fact, one of my big magnet numbers fell off because of the hard jolt in the transition area. In the straightaway, my speeds were high, about 125, but I wasn't flooring it at all, so I know I had lots more in the car. The problem is that I'm going to have to slow down for turn one, so why push that hard.
This is a pretty fun course and a good course to start out on.

Hope this helps.

Jane

 

IAT's are the intake air temperature after the supercharger. I have a data logger (my track doesn't like them so I put it in the glove box out of sight) With the data logger I record engine coolant temperature, intake air temperature, throttle position, vehicle speed, timing advance, supercharger boost and rpm. I want to go back to an old log to see if I have more timing advance with the new heat exchanger.

Thanks for the hot pressures Jane. If I can get the rear of the car to stick as well as the front currently is, the car will qualify as "stupid fast". I'll take video the next time. Hopefully with Stoptechs.

Les

Jane, you've always helped. Now if I'd just learn to listen!

 

Les: Road racing is an evolution, a process and a journey. Take your time and enjoy.

My journey from Princess to Road Racer makes for great stories. I'm still on my journey as I embark upon Chump Car racing - a whole new process of driving a piece of crap for 24 hours. Can't wait.

Jane

 

An update on the brakes. I took a look and the pads are worn out. I had checked them in January and they looked like new. Also, the peddle is still low and spongy so I think the fluid over heated as well. The stock pads will be going on along with a extensive bleeding until I can get what I need to rectify the problem. Has anyone put brake ducts on a Crossfire? I'd hate to be the Guinea Pig.

Les

 

Be careful Les - the repair manually specifically states not to pump the brake pedal to bleed the lines. They suggest a simple gravity bleed (or vacuum bleed) - Pumping the pedal only brakes up the air bubbles down into little bubbles and distributes them through out the system.

Get some ATE Super Blue or Castol SRF fluid and suction out the majority of fluid in the reservior. Then just gravity feed each line until pure blue...

I also like Porterfield R-4E compound pads....

 

summit racing has the motion powerbleeder. it is a great way to bleed the brakes and costs about 50$. every racer needs 1!

 

I'm using ATE Blue currently but will be changing to Motul 600. I didn't know that about using the brake pedal to bleed the brakes. I'll look it up. No problem though, I can vacuum bleed or gravity bleed just as easily. I'm using Porterfield R4S and until this last track day they worked great. The higher speeds with the new configuration of the track were too much for them. So, how do the R4E pads work on the street?

Les

I read the service manual and it says not to pump the brakes. All manuals say that so if done correctly the pedal method should be fine. However, I'm going to do the gravity bleed just to see if it works better than what I've been doing.

 

this is way better than a gravity bleed! you will have no doubt all the air is out of your system
Motive Products POWER BLEEDER Single Adapter Brake & Clutch System Bleeders

 

I replaced the Porterfields with the stock pads that were almost new. They look worse in person but you can see why I was having problems. The rear ones are still good but the front outboard pads are destroyed. One was even broken into 3 pieces. Picks of the gore.
I tried the gravity bleeding but I don't know if I put air in or took it out. Being alone I got out my vacuum pump and sucked some fluid out. I got a whole lot of air so I'm sure I boiled the fluid.

Les

 

My brake problems are going to be a thing of the past. Rob at Needswings has quoted me a good price for some Stoptech goodies and I intend to BUY BUY BUY! Janes experience with the Stoptech's helped me decide too. (I'm listening Jane) I'm outbraking Suby's and Porsches in my dreams and hope to at least match them while awake.

Les

 

You'll be very happy with the Stoptechs. They out perform Brembo's. The carbotech pads are fab. You will never smell your brakes. Plan to replace the pads each season.