Hi guys I just purchased a 2011 base coupe 6m trans. Has DTE trans/diff brace, DTE 300m output shafts and Johnny OConnell swaybars and shocks. D1 Procharger, Alky meth kit and supporting mods. 600rwhp. Question is how will this car launch with the upraded suspension? Anyone else drag race with Johnny O sways and shocks? Sways set on soft, medium or tightest? I plan to run 17" ET street slicks. I'm worried about wheel hop even with the trans/diff brace. Also installing an MSD two step and MGW short shifter soon. Recommendations on rpm setting for the two step?
Thx in advance.

 

Crickets in here...

 

I am just going to ramble on with no set order. You will have no regrets with the MGW shifter. I do suggest getting the lower box also. I have no personal experience with the rest of the mods you have listed. I have read the 2 step will make things break. You can not preload the drive train in a manual like you can with an automatic. I would ask if there are any other internal mods done to the trans and diff besides the 330m diff output shafts. I would suggest getting the trans output shaft upgraded to the 30 spline Z06 and the pinion made to except the 30 spline. One thing you can do is change out your rubber trans mounts to urethane. The urethane mount will produce more road noise in the cabin. This will help with the wheel hop. The oconnell suspension is made for road racing than the drag strip. An adjustable coil over shock will also prevent wheel hop. The install on the coil over shocks will let you remove the rear leaf spring. There are many more things that can be done. I think these are some of the basics.

 

thx man. I guess I'll just have to take easy initially. Two step will also be for street shenanigans.

 

I recommend against the two step, two of my experienced drag race friends installed them and promptly broke their rear ends.

If you would like launching tips, this is a great resource:

www.rangeracceleration.com

Pay attention to all sections including shifting and very importantly, clutch fluid maintenance. The procedures have served me very well for the last 12 years with my Vettes.

 

Thx Joe. Good read!

 

Car will launch fine. Don't think the base model has the launch control like the GS/Z06/ZR1, try revving her up to 4k RPM and see how it launches from around there (launch control hovers at that mark and seems to be pretty decent).

Don't have the Johnny O sways and shocks, so couldn't offer you any words on that.

Softer in the rear will allow the car to settle in on the back suspension and grab traction faster.

Sticky tires and tuned suspension should assuage any concerns regarding wheel hop. If the chatter is still an issue, maybe see about going with some adjustable coil overs to try and remedy it. Here's a link to the topic just in case:
http://forums.corvetteforum.com/c5-t...solutions.html

Don't do the two step.

MGW is a good choice. They no longer sell the shifter and lower box assembly separate, so you'll be receiving both when you buy it (for the former price of the shifter only, it's a great deal).

 

Just out of curiosity, what's wrong with using a two step?

Maybe the reasoning doesn't apply to me because my car's an automatic, but I think the thing was the best $200 I ever spent. Ever since I installed one it has been a LOT more consistent at the track because it totally eliminates the difficulty of trying to hit a target RPM when launching the car.

Prior to buying it, although I would usually aim for 1900RPM I didn't always achieve it. Now it's just a no-brainer in that I pre-stage, stage and then step on the gas and go.

The other benefit is that it allows me to make very small adjustments to compensate for how the staging lights are set up at different tracks. With Sonoma Raceway as an example, I can usually cut lights in the .030 to .040 range with it set to 1900RPM. At the first race after they installed new timing equipment at Sacramento Raceway, I initially couldn't figure out why with everything else being the same my lights were in excess of .100. Rather than try to adjust how I react to the tree, all I needed to do was bump up the launch RPM to 2100 and voila, my reaction times immediately went back down to where they were supposed to be.

 

"Car will launch fine. Don't think the base model has the launch control like the GS/Z06/ZR1, try revving her up to 4k RPM and see how it launches from around there (launch control hovers at that mark and seems to be pretty decent)."

My 2010 base model has launch control - put car in competitive mode, push accelerator to floor and the rpm drops to around 4k, and then dump the clutch. I've only tried it once and it was low temps so GY RF's didn't hook up very well. Like you're saying - keep rpms at 4k and it's pretty much the same thing - except I think the literature says the TC is monitoring wheel spin several times per second.

 

I believe on the C6 Corvettes it's better to have a stiff rear sway bar for launching at the drag strip. It helps the rear tires plant more evenly.

Prob why Pfadt chose the stiffest rear sway bar for their drag package.

 

With a manual car, the two step releases when the clutch pedal moves off the floor...thus, if you are just a little slow releasing the clutch, or if your clutch take up is a little high in the travel, the engine will be at the rev limiter. And you risk dumping the clutch too quickly as you hear the engine revving so quickly when the two step cuts out. You have to be very very precise with the clutch release timing when using a two step and both of the guys I know who had them released the clutch too slow, thus off the rev limiter, and broke their rears.

I find it a lot easier to modulate the launch RPM with my right foot. I know Gary2003Z06 agrees. Now he does use a two step for bracket racing but he has it set for a very low rpm and has learned to release the clutch so quickly the car doesn't over-rev. If I recall he basically dumps the clutch when bracket racing but the rpm is so low it hasn't broken anything yet.

But like me, when he's going for a record run, he uses his foot to control the RPM's during the launch, it's just a lot easier to control the process.

 

Two step is already intalled as of today. I like the shenanigans factor and will set it lower on track days. Thx for the info fellas!

 

BillH2121 - Good to know! I'm glad it was an option on all models (to be fair, I didn't even know I had it until only a little while ago ha).

Tiresmoke69 - Not exactly. If track conditions are optimal and tires are sticking well- then yes, stiffer suspension is better. If track conditions are poor or otherwise unsuitable for grabbing the road, the softer setup is better for the weight transfer to plant the tires.

Subfloor@CenturyTrans - see Joe_G's explanation. I personally prefer manual modulation for optimal RPMs, and on a wiggy setup like a two-step you risk a lot (especially at higher HP/TQ). Especially if you're not familiar enough with it to accurately handle the timing.

 

That's why I love my car so much - even a 21 year old novice can race it like a pro (aka my son).

 

Yea, it's also why you really don't see a manual car in any sort of serious drag racing series - we just can't compete given all the parameters.

If we could just dump the clutch like a 12 bolt chevy nova can do then that's a different story. Our cars take too much finesse to be as consistent as you need to be on the tree to compete with you automatic guys with a two step.

 

Joe,
You have pretty much hit the nail on the head except that I have broken in competition and had to change the right side CV axle in between rounds. This was on my MT 305/35R19 DRs street setup. Two step was set at 2500 and the track was extremely tight due to an X275 race the preceding day. Missed the second qualifier. I did not trailer the car this time so I raced on the only spare axle that I brought. I was overly cautious the first round and cut a 0.150 but as luck would have it, my opponent went red. The next round I cut a 0.65 slipping the clutch (no 2-step) but the Mustang cut an 0.014 by dumping his clutch. I fender raced him and took the stripe by 0.019 but broke out by a few hundredths. The Stang won the event because he could dump his clutch and cut 0.00x to 0.01x lights all day long. The guy was good.
The next race, I switched back to MT 26x11.50x16 ET Streets to run the 10.50 class on a Pro 0.500 Tree. The two step was set to 2200. The lights that day were -0.012, -0.013, 0.033, 0.044. The car reacted so quickly on the first two runs, I had to find a way to slow it down. (The car was extremely shallow barely lighting the second bulb.) Dropped front tire pressure and raised the rears til they spun on the hit. Went to the finals and lost to one of my buddies who was running an auto and going in deep. (I did tree him by a little; however, I smoked the tires, came out sideways, had a 1.77 sixty and ran out of real estate. 10.65 @ 134.66. Great race and a lot of fun.)
Back to the topic- Two steps are great for adjustable clutches or clutches that inherently slip on their own. (I would not trust the latter.) They do allow sticks to be much more competitive and keep you from over-revving in competition. Breakage is lessened at low rpm but not a guaranty. As Joe stated, a controlled slip is much easier on parts.
OP- I assume that you will be running some sort of skinny with the ET Streets out back. Those tires are very good in recovery and softer on drivetrain parts than a DR. Good luck.

 

Great advice Gary! Thanks for chiming in.

 

Thx for the info. Yes MT ET streets in 17". Still need skinnies but yes intend to run them upfront.

 

I have a very similar set-up to you but maintain the stock drivetrain with the exception of my clutch (McCleod RXT) an the car has no issue cutting 1.5 short times consistently. I think the 2-step has the potential to cause more harm than good, and ET streets are not necessary at that power level (still a great tire though). If you do not plan on running skinnies, just stick with a MT or Hoosier drag radial. If you plan on mounting up some skinnies with bias ply tires, then the ETs streets will be a viable option. I can't comment on the suspension set-up.

From 3/15/14

http://forums.corvetteforum.com/c6-t...a-si-trim.html