I signed up for an Autocross event this Saturday. You race the clock around a course set by orange cones. I'm told you 'might' hit 60 mph on the slalom course but I think it is more about acceleration, steering, cornering, shifting, braking etc.

I hit the dreaded 1 - 4 lock out often when driving aggressively. One question about that.....it was my understanding that if that light comes on you have to shift to 4th. But when I can't get into second, I go to 3rd with no problem...just wondering why I didn't 'have' to go to 4th? Maybe by the time I try and fail to get into 2nd and go to 3rd the rmps/speed has dropped down?

But that really is not my big question. Can I take off from a dead stop from 2nd? I suspect I probably can but is it advisable? On a short course, should I just go from 1 to 4? Looks like a couple of hairpin corners that I suspect I will have to drop my speed way back to like 25 or so. If I do that, is it worth downsifting from 4 to 2 or 3?

I guess I'm just a bit nervous. I don't want to embarrass my Corvette! I think I get 8 different laps so my goal will be to better my time each lap...if not each lap, at least have my last lap be faster than my first.

Any tips, suggestions, dos and don'ts are appreciated. If I never post again, it means I hit the wall at 140 mph. :-) J/K....there is no wall to hit.....

 

Start in first, use enough throttle and bring the rpms up enough to get second without the 1-4 light. Go to second. Stay in second.

But first, visit the Autocross and road racing forum on this site and start reading. Especially the sticky topics about your first autocross.

 

Fuse mod to bypass the cags 1-4, until you get a tune to tune the cags out that way, including not getting the dash light as well. Hence with the fuse, you will still get the light, but the trans shifter solenoid will not lock you out of 2 and 3 instead.

https://xse.com/leres/z06/cags.html

If you don't want to make the the resistor fuse, then you can buy one instead.
http://www.complianceparts.com/c6cagstrblshoot.html

Note, don't use a blown safety fuse, since the LED light will burn out after a while and end up with codes from that point isntead.

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As for fast lap times in a C6 on a low speed Autocross track, you need to learn how to skate the car for most of track, and use braking at the last moment so your under braking all the way to the apex to get the front end to weight transfer to keep the front end stuck. Bluntly put, the C6 is over powered for a low speed autocross parking lot work, and what you want to find is a medium speed type track to run the vet isntead (after you have some HPDE lessons under your belt).

 

In an autocross, you will likely be in 2nd gear the whole way. Skip shift will.not turn on if you'e driving aggressively, it only comes on at low throttle % and low rpms.

I wouldn' sweat it too much for your first autocross. Just go in knowing these aren' great autocross cars overall, too big and too much power. Most autocrosses are run by and for guys with stuff like miatas, so they'e constant direction changing, as opposed to sweeping turns or anything that a vette is good at. So just go out there and have fun.

 

 

High Performance Driving Experience. track days. on a road course.

Let the car slide an wander a little. Don't get upset or scared and over drive the car if it slides a little bit. You've heard of loose is fast?

 

 

 

uh. no. the 1-4 skip shift feature was added as a fuel savings measure to get Chevrolet to meet CAFE standards and get the Corvette below the gas guzzler tax line. If you're getting something different -- well, I guess it depends upon what you consider a wild hair. Sounds as though it's not wild enough.

if you soft pedal the car it'll make you skip from 1- 4. If you let the RPMS get up enough in 1 it will not activate that feature. I can't recall the exact parameters at the moment, but go outside, get in the car and shove the pedal down hard, run it up to 4 or 5k rpm and see what it does.

 

Autocross and road racing forum....

 

If you're driving aggressively you'll Never hit the lock-out to shift to 2nd. It only happens at very low throttle settings and less than ~20mph.

As for track days, they're held all over the country by a variety of clubs. Some have in-car instructors for new people, some don't. BMW and Porsche HPDE events are by far the most structured which is often best for someone new to the track. Other clubs are more "run what ya brung" and you're on your own.

Sometimes the track is full of cars and this one later in the day was wide open...



In general the events, especially the lower levels, are tightly controlled with passing in limited areas and Only with a point-by from the slower driver you plan to pass. The Advanced groups are less constrained or in the case of the video above we were open passing...ie semi race like.

 

I think the 1 to 4 skip shift cuts out at like 3k rpm. I'm wondering of your car was tuned to use the skip shift light as a shift light?

 

Seems to me it's closer to 2k.

Jalopnik says CAGS comes into play under the following conditions:
* you're in 1st gear (of course)
* you're at 35% throttle or less
* you're between 15 and 21 mph
* engine coolant temperature is greater than 171 F (77 C)

 

There is also a barometric pressure element in the formula. I can drag out the laptop and look at HPTuners later. too lazy right now

 

Rogillio,
You need to get yourself a CAGS Skip Shift Eliminator $19.95. Only takes a few minutes to install. I have a brand new one if you're interested. I have never been able to get my C6 to do the 1st to 4th skip shift, so I never installed it. Figured previous owner must of done the mod. The 1st to 4th light still comes on tho.

 

No, since the CAGS Skip Shift Eliminator $19.95 is just a resistor as well, and was needed on the C5 since the fuse in the engine bay was being used for more than just the Cags silinoid in the trans, and required that that on the C5, the reistor had to be placed at the trans.

So on the C5, you need this since the 2.2Kohm resistor had to be placed right before the cags solenoid on the trans, since back up line at the fuse box, the 10amp fuse was feeding more that the cags solenoid alone.


On the C6, Fuse #10 is only being used for the cage circuit feed wire back to the solenoid only, so the resistor can be placed in the engine fuse box, isntead of having to get under the car to install it on the trans with a plug type device shown above isntead.
https://xse.com/leres/z06/cags.html


Or as stated, if your soldering skills suck, then you can buy factory produced 2.2k ohm fuses that looks like a factory 10 amp fuse isntead.


Truth is, I still have my 2.2K fuse in my car from pre-tune day and have just not go around to swapping it out yet with a standard 10 amp fuse instead. Hence will come a time that someone without a tune may need it that I run across in person, and will just swap fuses with them to solve there 104 cags shift problem then.

 

 

2.2ohm resistor fuse, installed in the #10 , 10amp fuse location, will keep the trans shifter solenoid from blocking you out of 2 and 3rd.

The 2.2ohm in fuse body , still allows the BCM to check the trans shifter solenoid to see it so the car is not throwing codes, but does not allow enough voltage/amperage to go to the trans shifter solenoid to active it/block you out of these gears instead. Your still going to get the 1-4 light on the dash, but will not block you from shifting to second or third isntead.

As for running just 2nd gear (not using 1st), has mixed blessings, since now you will be slip feathering the clutch more out of the corners, and is going to burn the clutch up faster well (worse yet with not knowing how to stake the car to keep your speed up going into the corner, as well as coming out as well.

Hence with this being a base car, your first three gears are geared much higher than that of a Z51 option car, and will need to slip feathering the clutch even harder yet trying to not use 1st for exits out of slow corners instead.

 

All of the above is great information.

The very best thing that you can do is to familiarize yourself with the course. Watch the other cars, you may want to walk to track or take a low speed ride with a course worker. Mentally run the course as many times as you can. Finese is the key to a successful run, drive it clean, do not hit any cones and don't over drive the course. You must be in total control at all times otherwise you loose time slipping and sliding with unnecessary corrections. technique is the key, with the proper technique the speed will come.

 

I'm not sure I could disagree with that strongly enough.

Corvettes are fantastic autocross cars. Size is absolutely a downside and power can be as you're learning, but my GS is one of the most, if not *the* most, rewarding autocross cars I've driven. And that list is a long one.

To the OP:
1. get there early. knock registration and tech out before the rush
2. walk the course as many times as you can...you'll definitely not have any fun if you don't know where you're going
3. talk to people. don't keep it a secret that you're a novice...folks will generally be willing to help.
4. ride with experienced folks or have them ride with you if the club's rules allow