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Ben Lipman Goo Roo SA Soarer TT manual, plus TT track car
Posts: 2735 Reg: 04-2006
Rating: N/A Votes: 0
Saturday, April 02, 2011 - 08:57 pm, by: Ben Lipman(Ben12a)
A mixed bag. The car was faster (yay) but felt horrible to drive. I wasn't there to set times, but when I was bedding in thew brakes I noticed I had run a couple of 1:24 second laps, almost by accident. When I put the foot down I ran a 1:22.5 on the racechrono.
The problem is it is suffering badly from power oversteer, and also a bit of oversteer under brakes. It turns in nice, but the rear wants to do it's own thing.
I am going to download the race chrono later and look at the speed traces. It could just be that due to the front tyres being new and I have a decent amount of camber the corner speed is up and this is taking the rear tyres beyond their limit. The rears don't look that bad.
I'll set up the string lines and check the alignment as the steering wheel feels a little off centre and I went off at the northern hairpin, so it wouldn't hurt to check. When I ground out the LCA mounts I took out different amounts of material to even up the camber. I never considered I was changing the toe at the same time. I'll remember that for next time.
So all in all, the car is faster, probably due to the tyres, but handling is no good.
I also managed to set up the manometer. The problem is that there is very little straight track to check the pressures at a steady speed. I did manage to get some readings down the back straight. The oil cooler has about 1/2 to 3/4 of an inch of water pressure difference front to rear. This is not good, highlighting the need to get air flowing away from the rear of the cooler core.
I also measured the area I want to place the vent. The pressure difference between the top of the wheel well(inside) and top of the guard is confirmed at 2 inches of water at about 120kph. Once again there was only a small window to check.
It is my belief that if I put a vent at the top of the guard, this should extract air from the inner guard which in turn should help airflow through the cooler.
It is worth noting when I turn the fan on whilst parked in the garage there is about 1/8 inch of positive pressure behind the cooler core compared to the front. The fan can pull the temp down quicker static than a cool down lap, so the airflow in this area really needs work.
