Pablo

iTrader: (1)

I was finally able to participate in a Time attack here in Sicily. This took place a couple months back but my friend just uploaded the video so I thought I should share.
There were almost 60 cars and I got third place overall. The two cars that ran faster times were a brand new Nissan GTR, and a Lotus Super 7 which is this ridiculous open wheel/open cockpit thing. There was also a guy there in a prototype that was just doing exhibition runs that blew everyone away.
I don't think I did too bad considering both of those cars ahead of me that were actually in the competition probably had double the power to weight ratio I have. I also outran quite a few dedicated race cars, mostly fwd compacts.




Here is the video of my second session. Ahead of me is a Ford Sierra Cosworth. The action starts at around the 2:25 mark. You can see on a couple of the tight turns I was pushing real bad. I attribute this to not having enough ackerman though my driving didn't help. But overall I was pleased.


Thirdgens can handle really well if you set them up properly.

AlkyIROC

Third gens are really designed for road racing although we like to race them everywhere. It just takes a bit to figure out a good setup for each type of racing.

It's hard to get a feel for the track by just watching a video but I can see when you're trying to power your way out of the apex of the turn that you have to let off the throttle a bit to get back onto the line.

Manic Z

iTrader: (1)

Can you tell us a little about the car?
Engine? Wheels? Tires? etc.

RS Chris

Nice. Way to represent the thirdgens. As for your pushing problems, a suggestion might be to brake slightly earlier, roll or coast more through the center and not pick up the gas so soon. I know it sounds weird but it would let the chassis settle just a tiny bit before making the next input or direction change. Again its just a suggestion based on the video.

TPI-Formula350-

this is from his sig.
91 Z28 LB9 T5, Time Attack Car
315/335 Hoosiers. 6 point roll bar, konis, heims, aluminum, D44, etc, etc

Pablo

iTrader: (1)

yes, looking back on it, I would definitely drive the course much differently. There's definitely a distinction between knowing what to do and actually doing it on the track. That was essentially my first session ever on that track. I was also sleep deprived, and hot as hell, (had to drive with the windows closed though I left one cracked) so my driving was not as good as it could've been.
A lot of the problem with the tight turns is that if I let off too much, it scrubs a ton of speed. Just imagine a pair of 315mm hoosier R6s toed in too much. It acts like a brake. That said, I should have really tried to late apex iirc turn 5 (the tight one) among other things.

About the car:
I'm here in Italy with the military. I brought this car with me and was previously racing it in CA (video link of that in my sig)

There are very few name brand parts on this car, my focus is, and has been, on fixing geometry, reducing weight, and increasing grip.

The engine is a basically stock "lb9", actually the long block looks like a generic replacement rebuilt L03 (was in the car when I bought it), it has swirl port heads but the cam is definitely no peanut. It's a stockish grind (no lope) but pulls too hard to be a peanut cam.
-Headers, magnaflow exhaust
-Serpentine delete, went to aluminum pulleys and accessory brackets + aluminum water pump (17 lb drop)

Transmission: Stock T5 with a poly trans mount
LS1 aluminum driveshaft with the shorter thirdgen front yoke (there's a reason for this)
Dana 44 rear with 3.73 gears, and a shimmed trac lock diff

Brakes: Stock 10.5" front, Stock PBR rear disks. cheap Dot 4. Adjustable proportioning valve.

Rear suspension: aluminum LCAs (shortened) w/rod ends- rear axle moved forward 1.25" (hence the shorter driveshaft)
LCA relocation brackets, set to about level
aluminum panhard bar w/rod ends. Panhard lowering brackets, phb lowered about 4" (lowered roll center)
Koni yellows with shaft mounted bump stops
250 lb/inch springs on adjustable spring perches
24mm sway bar, sway bar clamps made adjustable (slid all the way inboard) poly sway bar bushings
stock torque arm

Front suspension: Spohn upper strut mounts (they suck but I "fixed" them), Koni yellows
Howe 1/2" taller ball joints (raised roll center)
moog 5664 springs, half coil cut
poly bushings
36mm sway bar

Chassis: wonder bar
6 point roll bar
Mini-tubbed and reinforced rear wheel wells (kind of a big deal)

Weight reduction:
Fiberglass hood, no AC, no heat, no radio, gutted interior (but intact dash and center console)
Ergonomics:
Ultrashield aluminum road race seat, G force 6 point harness

Wheels and tires:
Front: 315mm hoosier R6 on 17x11 CCW classic wheels
Rear: 335mm Hoosier R6 on 17x12 CCW classics

I might be forgetting some things but that is about it. I chose to spend money where it counts and I think it shows in how capable the car is.

The next thing I am going to do is fix the ackerman, the car likely has anti ackerman and if not, it doesn't have nearly enough ackerman for tight courses. After that I am going to put in the .75" taller ball joints to get the front end slightly lower.
I have the parts on hand, just have to get around to installing everything.

InfernalVortex

iTrader: (4)

Do you heel-toe when you downshift? I have a super hard time trying to do that on mine and I blame the pedals and lack of flexibility in my foot.. I just cant contort them right. Im thinking I need to adjust where my gas pedal is and build an adjustable stop under it, but whatever maybe I just need to try harder.

Also you have no road race pan or accusump or anything like that?

Pablo

iTrader: (1)

I do heel-toe but not always, you can hear it in this video coming into the cone chicane a couple times. Other times things just seem to be happening too fast for me. I'm not sure if that is due to the tight courses I run on or not. I'd like to think that if I was on a great big road course I'd have plenty of time process that in addition to the rest of the driving.
The thirdgen pedal placement doesn't help. I think the gas pedal is too far forward relative to the brake. What I did was put one of those cheapo pedal covers on the gas pedal to space it closer to me, and left the brake pedal bare metal. Then it's a matter of rolling the foot over.

And no, I have nothing to protect the engine from oil starvation. I haven't even been able to pay attention to the oil pressure mid corner so I have no idea if I'm getting ready to grenade the thing

AlkyIROC

Even on my drag car I felt the same way. My seat is positioned back farther than stock so pushing the pedal to WOT was difficult. The factory pedal is long gone. I now have a different pedal assembly mounted away from the firewall and it's just about in line with the brake pedal. I also use a throttle rod instead of a cable.

InfernalVortex

iTrader: (4)

Do you mean the gas pedal is too far back compared to the brake? if you're making the brake pedal thinner and the gas pedal thicker wouldnt that mean the gas pedal is too far back?

JesseShredd

I'm tired of snapping cables and was curious about this rod setup. Did you fab it yourself?

paul_huryk

How are the stock 10.5" front brake holding up in such events?

ibmtech

iTrader: (1)

I was actually impressed as it worked the course fairly well. I know I wouldn't have done even close to that good.. It is alot easier to just go straight... LOL.. I think the most impressive part of the entire video was when you passed the other car. Good job on the car and thanks for a great video

Pablo

iTrader: (1)

I mean the gas pedal is further forward relative to the car, and farther away from the driver. The pedal cover makes the gas pedal thicker so that it is closer to me, and I have no cover on the brake to make it further from me.
I can't say it's done a whole lot but it's something.

Pablo

iTrader: (1)

I have never felt brake fade. I think the best mod is the adjustable proportioning valve. I have dialed in way more rear brake than stock, so now instead of only the fronts turning speed into heat, I have better distributed the load among all four rotors. The car stops in an unbelievably short distance too.

I also have room to improve just by swapping to a decent brake fluid (like castrol srf) and installing the hawk pads I have sitting here. So far I have been doing all of these events on parts store "duralast" brake pads. I did crack one of the linings once but never felt any difference in braking.

To be fair, all of these events have been on short tracks under 100 mph

IBMtech, Thanks for the kind words. Yes, I think that most people don't come anywhere near reaching the limits of even the stock brakes, and larger brakes don't improve stopping distances (in pre fade conditions)

RWB____s

good job pablo! I had a problem with mine on course years ago. It pushed badly and it was costing a lot of time. I kept trying to give it more gas in a certain section of the course trying to get the tail kicked out and it only pushed BADLY. after my 1st run, another dfriver saw what was going on and told me the car was fine . it was the nut behind the wheel trying to go to fast in a area were slow was faster. I made my next run slowing the car through the section. the push/understeer went away and i improved my time a full second!!! So sometimes slower is faster!

Still got the GW torque arm you got from me?

Pablo

iTrader: (1)

Hey Ron, how have you been? Still doing the drag racing thing?
I definitely needed to slow down more for that turn, I just hate slowing down I'll see if the combination of an ackerman fix and driver fix don't help the issue next time I head to that track.

I do still have that GW torque arm. It's sitting in my garage. I haven't been very anxious to try it on the car because I'm afraid it will make brake hop worse and I don't have a problem with traction moving forward. The dang thing is also pretty heavy. Despite all that, I have been wondering if the stiff construction would actually help improve the brakehop even though it's a shorter arm. I might get around to trying it eventually. I need to do more research on it.


Hey AlkyIROC, I was meaning to ask if you had any pictures of your pedal setup or could share some details? Sounds like something I should consider.

RWB____s

Im doing ok. The car is ok as well. made the transformation from autocross to drag race. I miss the autocross events, but there is none where I am located at. plus the drag strip is 20 mins from my residence.