More RCR T70 Testing at VIR

[Ron Earp]

This past weekend the team finished up some T70 testing at VIR. Jeff G and I had made a fairly large array of changes to the car over the last few weeks and we were anxious to see the fruits of our labors. We performed many alterations that involved sway bar, end links, ride height, brake bias, spring rates, alignment, and some other items. Our car ran flawlessly throughout the day although start up in the morning revealed that our smoke pump only had one case screw holding it together. We were able to scavenge screws from another unit and button it all back up.

According to our test driver (Jeff Young, club day at VIR) feedback the continued development paid off handsomely. We had four sessions on track and continued to get good feedback from the driver while at the same time altering the driver’s habits to match the car. None of the test sessions were driven at 100%, instead we worked on certain techniques and corners throughout the day to evaluate various aspects of the car. In short the car is much improved over our outing last year at CMP. It seems to be predictible and was pronouced “raceable” – a big step forward! Now we have to work on sorting fine details of driver comfort, developing speed in the driver, and continuing to ensure the car behaves reliably.

Here are a couple of in car laps from VIR. The best we managed was around a 2:13 or so, but again, we’re not at a max effort. For example the Traqmate data showed we’re developing 122 mph in the uphill esses but backing off to 85 mph for T10 since T10 wasn’t a corner we were working on. This occurs in other areas of the track as well so we feel that a 2:13 is quite respectable, given only about 235 hp at the wheel and 2340 lbs.


http://www.youtube.com/watch?v=OM0mqq5I_Lw&feature=mh_lolz&list=HL1311087366


<iframe src="http://www.youtube.com/embed/OM0mqq5I_Lw" allowfullscreen="" frameborder="0" height="349" width="425"></iframe>


Oh, we did learn a little about our fuel endurance and we might have overshot our target if the data is correct. Two tests have shown we get about 0.7 hours of run time from five gallons of fuel at the moderate driving level we’re at now. If that is correct then it seems possible that the car could run for a bit longer than 2.7 hours on a fuel load. That is certainly longer than our two hour target, however I imagine that endurance time will shrink considerably with harder driving. On the other hand, running 2:13s with 2.5 hour driver stints could be a car which would be hard to beat. Fuel stops in the 13 Hour are a time killer and the high horsepower cars that are in every hour, or less, really suffer.

All in all a great test day and we’re looking forward to the UTCC this Friday. We’re treating that as a test day too and I will have some sessions behind the wheel then.

 

[flatchat(Chris)]

Looks like a walk in the park, Ron --and that you can start building confidence in it now :thumbsup:

 

[Ron Earp]

It was good to see the effort pay off in the form of a car working well. Back out again this weekend and we're hoping the SLC comes down to VIR as well. I think that team has a good chance at a win if the car is repaired by then.

 

[J. Salmon]

Crap! The one member day I miss (my Lola is down for a bunch of refreshing). Would have been 2 yellow Lolas...

Those are nice smooth laps. That's going to be serious fun, and physically tough too. 2.5 hours at that pace will be tough enough. In traffic it will be a real mental test. Looking forward to the UTCC report!

 

[Justin]

Wow!!! Looks like LOTS of fun!!! Love the T70 videos. Keep them coming.





Ugh... One day, a T70 or an SLC-LeMans...

 

[Jack]

Keep at it Ron, like eating an elephant!

 

[Ron Earp]

Crap! The one member day I miss (my Lola is down for a bunch of refreshing). Would have been 2 yellow Lolas...

Your SLC was running just fine though. Sounded good and looked smooth.

 

[Jeff Young]

Car does still beat you up a fair amount. You are always bracing yourself with your legs and upper body. At 135 mph on the backstraight, you feel like you have two midgets trying to remove your helmet.

But other than that those were pretty easy 2:13-14 laps. About the only place I was pushing the car was the esses -- that was apparently 122 mph up the esses according to the data -- and even there we left a lot on the table.

I think a sub 2:10 lap is very doable, and an enduro pace of 2:13 or so very achievable.

 

[Glenn M]

"At 135 mph on the backstraight, you feel like you have two midgets trying to remove your helmet."

Brilliant Jeff, made me spill my morning tea!

Looks like you're really getting there guys, all those hours are paying off now.

Glenn

 

[Randy V]

Car does still beat you up a fair amount. You are always bracing yourself with your legs and upper body. At 135 mph on the backstraight, you feel like you have two midgets trying to remove your helmet..

You need a better (taller) windscreen. The short windscreen I had on my Cobra did a very good job of putting an envelope of calm air around me. Also - Kirkey makes leg extensions for their seats which will give you a much better feeling of being "Connected" to the car. Those things and a properly fit and tightened harness should have you much more comfortable and safer inside the car.

crummy picture - I'll look for a better one..

 

[Terry Oxandale]

Engine sounds a bit rough. Rods maybe?

 

[Ron Earp]

Wind noise, I can't hear the engine at all in the video. Engine is fine and sounds good. We don't turn it over 5600 RPM but it still sounds pretty good when it goes by. We do have a lot of rust in the coolant though and I suspect the block wasn't properly cleaned by the fellow who assembled it. However, it seems to run well, doesn't burn oil or water and gets the job done.

Thanks for that info Randy. I'll check the leg extensions and we do have a taller windscreen already, it is just that it obscures apex vision.

 

[Ron Earp]

Here are the suspension settings we ended up with for the car:

RF - 99mm ride height, -1.25 camber, 522 lbs, 7.2 caster
LF - 99mm ride height, -1.30 camber, 508 lbs, 7.1 caster
RR - 103mm ride height, -0.25 camber, 651 lbs, 6.2 caster
LR - 103mm ride height, -0.25 camber, 661 lbs, 6.6 caster

Front springs 1000 lb/in, rear springs 850 lb/in; front roll bar is hollow 1" with approx 10" arms, no rear roll bar. Total toe is about 1mm in, front and rear, and I suspect this either holds there or evens out to zero toe while the car is in motion.

With this setup we achieved good tire surface temps - all tires were within 10 degrees across the face in the 175-185F range. Starting tire pressures were around 30-31 psi, finishing up around 36 - 37F hot so we could stand another psi or so. The car would push on a 300 ft diameter skid pad in the dry with the front roll bar disconnected. I suspect this setup would be reasonably applicable to RCR GT40 replicas and certainly usable on an RCR T70.

 

[Jeff Young]

Engine is fine. Sounds and pulls strong.

 

[J. Salmon]

I have a duck bill helmet, and mine will still try to leap from my head if the wind gets moving the right way. Seems to be a little variabiliity, like even a few degrees different angle on my head or a 1/2 inch difference in where my butt is placed can make a bit difference.
Sometimes I end up pushing back on the headrest to "hold" it on!

122 in the essess is pretty damn impressive. That's one of my better sections of the track, and I think 110-112 in my FF is... "exciting". I think I'd wet myself with another 10 mph. That's the section I think would be a real mental challenge for long periods of time.

Hope to see you guys at another member day later in the year!

 

[Jeff Young]

I've done about that in the TR8 (112 or so) and the Lola felt much better at 122. Different approach though. It will "take" more steering in put up there than the TR8. The 8 likes you to run the curbs and try to straighten the line as much as possible.

The Lola wants off the curbs, and wants you to use the mechanical grip to turn the car.

Fun.

Turn 10, different story. Still working on that sucker.

I have a duck bill helmet, and mine will still try to leap from my head if the wind gets moving the right way. Seems to be a little variabiliity, like even a few degrees different angle on my head or a 1/2 inch difference in where my butt is placed can make a bit difference.
Sometimes I end up pushing back on the headrest to "hold" it on!

122 in the essess is pretty damn impressive. That's one of my better sections of the track, and I think 110-112 in my FF is... "exciting". I think I'd wet myself with another 10 mph. That's the section I think would be a real mental challenge for long periods of time.

Hope to see you guys at another member day later in the year!

 

[Malcolm]

Going up those esses is one of the best bits of the track, certainly they would be part of my dream track should I ever build my own! I think we pulled about 100 in the SM, certainly that at the bottom of the hill. A bit of extra speed must be hoots of fun!

Glad to hear the car is getting nearly race ready.

 

[Ron Earp]

Hey Malcolm,

When you build that dream track make sure you have some Spitfires and ME109s up on pedestals in the infield.

Development is continuing and I think we're closing in on having good running T70. Off to load up for the UTCC at VIR.

R

 

[Jack Houpe]

That is awesome Ron, good for you!

 

[Malcolm]

Hey Malcolm,

When you build that dream track make sure you have some Spitfires and ME109s up on pedestals in the infield.

Development is continuing and I think we're closing in on having good running T70. Off to load up for the UTCC at VIR.

R

Planes added to wish list! Good luck for the UTCC runs.