A bit of maintainence and some more modifications to Baby Monster...
This 2.5" inner diameter (ID) high-flow catalytic converter was removed:
and replaced with a 2.5" Boss Frog stainless-steel test pipe:
Exhaust sounds sans boost:
Vertical skirts were added underneath the body:
Tech: Originally seen on the 1977 Formula 1 (F1) World Championship winning Lotus 78 race car, vertical side skirts were used to seal in underbody air flow and greatly improve the efficiency of underbody aerodynamic components (i.e. flat bottom, rear diffuser, etc.). The vertical side skirts would act as walls to keep turbulent air from the outer sides of the car away from the underbody, and they would act as guides to maintain the smooth air flow under the car. Due to various reasons (perhaps some combination of politics and safety concerns), vertical side skirts were eventually banned from F1 in 1983, and were subsequently banned or highly restricted in other racing series as well.
Luckily for us, the events we drive in don't impose any restrictions with this type of aerodynamic component.
We realized that the front splitter support rods did not support the front part of the splitter too well. It turned out it was because the factory sheet metal that the support rod bracket was mounted to was very soft and flexible:
So we welded in an extra plate and re-did the support rod bracket:
We also dumped out oil from the Greddy oil catch can, and made the change to Mobil1 engine oil filter and Mobil1 15W-50 fullly-synthetic engine oil after what we believed was a reasonable break-in period:
To make sure our front splitter and rear wing would hold up to the massive aerodynamic loads we might see at the "fastest road in the west," we found a 145 lb. monkey to conduct some structural testing for us...
He checked the rear part of the front splitter:
He checked the front part of the front splitter:
He even checked the rear airfoil:
We are looking forward to having a great time at the WSIR Balcony and Big Track this coming weekend. Drifting, time attack, and perhaps some wheel-to-wheel are on our agenda. Come out and say hi if you're in the area!
Came back from a successful test day at the Streets of Willow Springs (SOWS) with Speed Ventures. We ran in the CCW direction. Those familiar with the track and incident history will know that running CCW is actually safer than running CW here.
Headed out from Orange, CA at 3:00am, picked up a member of our crew (my cousin Mike) in Monrovia, and arrived early at the MacDonald's off the Rosamond Blvd. exit. We ordered the Deluxe Breakfast for "dine-in" and proceeded on to an early arrival at SOWS.
Parked the rig between the main building and the breakfast/lunch truck, unloaded everything, and spent a bit of time training the "new guy" (Evan) how to run the AMB timing equipment for Speed Ventures.
There were probably less than 7 cars in Red group (the group I drove in) throughout the day, and only 40 or 50-something cars total for the entire event. It was quite a relaxed Friday at the track.
In the first and second sessions in the morning, I drove the car on the 225/50R15 RA1 tires, lower boost setting (11psi), with passenger. The lap times started around 1:32 and eventually got down to a 1:28.7 at higher boost (15psi) and with some changes to the shock settings and tire pressures, also with passenger.
Just past mid-day, our friend Joey Leh from The Octane Report (http://octanereport.com/) arrived at track and parked next to our spot to get some coverage on our Baby Monster. He attached video cameras to the outside of the car, took pictures and video from 3rd person angles, and even installed a Traqmate GPS data acquisition unit inside the car. This was much more than I would ever have done on my own. Thanks Joey!
We had Aaron Bitterman of Speed Ventures take the car out for a few hot laps on the RA1s with no passenger. He managed to score a fast lap time of 1:26.053 on his 2nd hot lap ever in the Baby Monster. He was still trying to get used to the response of the turbo at 15psi (we actually hadn't tuned the Greddy boost controller very well for the 15psi setting yet), and the taller sidewall of the 225/50R15 RA1 causesd some handling/balance issues. Other than those minor details, Aaron stepped out of the car quite pleased with it, and said that mid 1:24.xxx lap times were definitely possible on RA1s or equivalent tires.
I then gave Joey a few laps of ride-alongs just as the ambient temperatures soared past 95 degrees F, and only put in a best time of 1:29.x during this run. I threw in some intentional sideways action in the skidpad for a good time, which I hoped Joey would have enjoyed. He did say it would have been nice to capture that sideways action from the 3rd person point of view, but alas, he was in the car when it happened.
For the final session of the day, we swapped the tires out to the 275/35R15 Hoosier A6 to see what kind of fast lap time the Baby Monster could do. I went out for a total of around 3 hot laps without passenger and managed to get a best time of 1:25.252. This was good enough for the fastest time of the day for all cars, but we think this setup should at least be good for a 1:22.xxx lap time with the right driving (or right driver?).
Throughout the day, we did get some minor heat issues, but only on the 4th straight hot lap, and at lower speeds. The oil cooler and intercooler are stacked in front of the radiator, which is not a good thing for radiator cooling. We plan to open up one of the blocked brake duct openings (the blocking plate is bolted in and easily removed) in the bumper and just plumb it to the front of the radiator.
The paddocks were deserted by 5:30pm (boy, people sure left quickly). We were the last to pack up and leave. We headed back to town at a leisurely 55mph pace and had some Taiwanese food for dinner at Sin Bala in Arcadia.
In all, we felt quite pleased with what the car could do in hot summer weather, considering we had actually set this car up more for a higher-speed track such as Big Willow or Buttonwillow. The car had so much grip in some areas that we wished it had more power. Just imagine this: 250whp in a 2230 lb. car, wide open throttle after the bowl CCW in the off-camber right-hand turn...hugging the inside line. That's not just mechanical grip. That's also aero grip - a pretty good amount of aero grip that can be felt and utilized even at speeds starting as low as 55mph.
Here are some analysis graphs from the Traqmate data file gathered during Aaron's 1:26.053 hot lap...
Brake and turn zones map from the Traqmate data file:
The Traqmate data file from Aaron Bitterman's 1:26.053 lap is available for viewing here: SOWSCCW Test OR Test 5.tqm
You can download viewing software from http://traqmate.com/ to analyze this file and to play back the lap in real-time.
Unfortunately, technical issues kept the unit from recording anything during my Hooser A6 hot laps.
Once again, thanks to Joey Leh for letting us use your equipment to get this awesome data!
Even with the widebody, the 949Racing 15x9 +36, Hoosier A6 275/35R15, and 30mm spacer combo turned out to be a pretty tight fit for the front. The effective back spacing on this combo is actually some number greater than 5.23", since the tire is somewhere north of 10" in width (it even makes the 9" wheel look small). Turning too much causes the tire to rub against both the body seam and body surface inside the wheel well. It shouldn't be a problem in typical grip driving conditions. But if we ever get sideways or off-road action, then it could perhaps be a problem.
Front, about 1cm outbound:
With the front control arms looking like a "Y" already and with static front camber at -3.25 deg., the top of the tire does tuck in quite a bit under compression while the car isn't moving, but we have yet to find out how things will be in motion.
The front and rear fenders on the Autokonexion widebody kit were made as a staggered setup: the rear fenders were "wider" than the front fenders. We also previously extended the rear fender even more by separating them from the body with additional bracketry. So, the rear fitment was not a problem at all.
Rear, about 1cm inbound:
Tech: Some folks have questioned why we pulled the rear fenders away from the body. This modification was done to provide a relief for high pressure air that might build up within the wheel well at high speeds. Having air trapped anywhere at the bottom-side of the car is recipe for increased lift. We don't want lift. Lift is bad. So, having this fender gap available for air to escape from this part of the car is just one small recipe (out of many) for lift reduction and improvement in aero grip.
