Bump! I was hoping to have all sorts of tuft testing or proof that the new aero stuff is awesome. Instead, it's mostly been scramble in free time to make adjustments and sort issues as they arise.
Since my last post we've run 2 gridlife events and 2 local autocross events. Overall the car has been good, after the first gridlife we decided to lower the car a bit to try to get more front bite.
This is the amount we lowered the car (about .75"):
This ultimately acheived our goal but we way overshot, the front edge of the splitter would dig in under heavy braking zones and cause a shudder throughout the car, which would trigger ABS, the solution was to raise the car back up .25" and then raise the front mount of the splitter by .25"
I'm working on some splitter skids as well for rougher tracks as the splitter still sits about .5" lower than previously thanks to the increased rake.
The other thing was this made the car incredibly loose in the back, we wound up having to not only dial out some compression in the rear but also wound up removing the rear sway bar.
During one of our sessions after lowering the car Matt wound up oversteering and sliding off the track backwards into some grass. He was able to drive back onto the track and pulled into the pit to be checked over. When he stopped moving the lack of airflow under the car caused some of the still stuck grass to ignite on the hot exhaust which quickly caught some of the oily bits below on fire. Thankfully the fire crew was nearby and the only real damage was a melted wideband o2 and some reverse light wiring.
That prompted the install of this, which was probably something that should've been in the car long ago:
We've been dealing with some heat soak issues also, previously we'd do 2 laps, cool down, 1 more hot lap then the session would be over. For this year we're really targeting doing 3 hot laps back to back to back in preparation for the 2019 One Lap of America where you have to do that twice a day for a week. Water temps have never been an issue since installing the CSF radiator, however the C&R oil cooler didn't seem to be able to keep up with the heat. So, enter this massive piece from Setrab, oil capacity is now up by a full 2 quarts, and it's rated for 50% more hp than I'm making!
We learned as it turns, out, all that extra blockage in front of the radiator means that now the radiator isn't getting the airflow it was before which caused coolant temps to go up. After 2 laps water and oil temps were high enough to worry us into back down, sometimes even midway through the 2nd lap. Great, money spent and we made the car worse.
Since we were at Gridlife when we learned this interesting bit of information there wasn't a ton of options or time between sessions, Thankfully Gingerman is only an hour from my house so my brother in law brought out some power tools and a beat up spare bumper from a car we parted out:
This seemed to help a bit, oil temps were still just as bad as they were previously with the C&R cooler BUT, we could now do a 3rd lap at speed without getting into the "DANGER WILL ROBINSON" area.
A bit of temp data from the AIM, all sessions shown were within 5-10 degrees ambient, so not a massive swing.
2 laps in green are from last fall with the C&R oil cooler in factory location and CSF radiator
2 laps in blue are from this summer with the new cooler in place
2 laps in red are after we cut up the bumper
So, we've got temps back down to where they used to be with the old setup, ie. no improvement. Not captured in this data is that oil temps would continue climbing steadily for the green laps if we started a 3rd one, meanwhile the red laps sort of plateau and hold. so we did get a bit of improvement in length of time we can push the car.
And that brings us up to today. If some is good, more should hopefully be better?
Adding much more comprehensive ducting to the cooler stack:
We're also trimming up some angle to help try to get the hood vent extracting more air (and have added a massive 2600cfm radiator fan instead of the 1500cfm one on the car previously)
Hopefully we see some improvement here and none too soon as our next track event is only a week away at Autobahn and the Optima Autocross in Grissom is this coming weekend.
The last idea I have still in mind for cooling is a larger intercooler, get rid of the end tanks blocking so much of the lower grille and instead have it be entirely core, with the end tanks tucked behind the bumper, this should increase airflow which seems to be the best things we've done so far to heat reduction.
You can see how much space they waste, but with how far outward the charge pipes are I think it's possible to fab something while keeping the same piping. Unfortunately I'm not a welder so I'll have to farm this work out.
The core which comes with this kit is 20x8x3, I don't see any brand markings on it but I have my suspicions something like the 24x8x3.5 core from Garret might actually let more air through to the heat exchangers as well as cool my IAT's down more (not something that's been an issue but it can't hurt)
I'll make sure my update is not 2 months away this time and hopefully I have some positive cooling results to share!
