D.Woods

I've got some advice from a few well respected members in here about drag racing my bolt on C5Z, but wanted to ask the forum b/c I've been thinking about it too much...

Will going with the ET Street with my stock gearing still be better than going with the Hoosier 275/40/17 DR (I'll have skinnies up front and C5Z stock 17's on rear).

I'm mainly just wondering about the gearing, and the fact that everyone says the ET Street is even taller than 26, AND it will swell at the end of the track...

I know it will be better on the drivetrain, and more consistent, so I'm all for that I just don't know how big of a change that will be on the gearing. I'd like to take them to the street once or twice as well in case there's anything needing to be taken care of out there, lol, but my 4th gear already will run to right around 150mph with the 295/35/18's on back (not that I'll be doing any of that on the soft tires, just saying)

So I ask again, just for a sanity check, is it most ideal to go with the bias ply ET Street, even at the risk of making the gearing even worse?

Mods are as follows:

LT's/full exhaust
Vararam
PCM Tune

Car made 384/376 on a dynojet

Car ran the following times on a crappy 1/8th mile track (so crappy that it closed down this year) with really worn NT-05's

1.85
7.91
93.18 mph





I plan to most likely spray it in the next year, but I may go ahead and throw a cam in instead b/c I miss the sound of an LS pounding the ground haha

C5 Pete

Typically, for a bolt on car with a stock clutch, the Hoosier 275/40/17 is the tire of choice. It hooks well and is stable throughout the pass. , plus, as you mentioned, it's short, so that will help (even just a little) with the gearing.

However...

The thing with the bias ply is this... The tire height won't make that much of a difference. You can launch harder with a bias tire because, 1) it is easier on parts, and 2) it recovers from spinning quicker. You want a tire to spin just a bit during launch to soften up the blow to the drivetrain, while still encouraging the car to move forward.

If you're only running for a new best ET, buy the Hoosiers. If you're bracket racing, get the bias ply tires.

Either way, have fun and be safe!

D.Woods

^ thanks!

Oh, and to throw another wrench in there, you mentioned clutch...

I forgot to mention the built trans, McCleod RST, and trans brace that are fixing to go in. Does that change anything, or make anything easier to answer? Lol

And I'm assuming the alum flywheel isn't worth it either, but figured I'd mention in case the opinion is different than what I thought.

C5 Pete

How much track time are you planning on?
The RST will not last long at the track, while the RXT will eat tracks for breakfast and ask for more.
Have you already bought the RST? If so, send it back and get the RXT.

Aluminum fly wheel is not advised for the basic drag racer.

D.Woods

Maybe 20 passes or so per year, and an autoX or two? Speculatory, but just an idea. Only got to make one 1/8th mile track outing this past year in it (first time in it) and made 10 passes, but plan to make a few trips to the 1/4 this year.

I'd love to get to an HPDE in the next two years but that's just in the hope/wish pile. Not something that I am counting on happening, but I'd like to.

Is there any down side to the RXT , other than price diff and maybe a stiffer pedal?

robz

For drag racing a c5Z, running the bias ply will help you learn the launch much quicker with any clutch you choose to run. You will have more fun launching and can be more aggressive without having to discard passes especially when you may only get a few each time out.
The stock clutch should work for a while and is easier to figure out.
And , as Pete mentioned, don't sweat the increased diameter as it won't make as big a difference as the slick will help on the launch.

D.Woods

Thanks fellas! Robz: the clutch is already done for. I got to put ten whole passes on it. Is that enough time for learning? hahahaha

You hit the nail on the head tho Rob. Of the 10 passes I made on that poorly prepped 1/8th mile track, the ones that weren't good, were bad! I aborted two or three of them. I was playing with air pressure and tire temp and hit the spot it ran the best pass at. Lowered the pressure 2psi for the next pass and tried to go with a higher rpm but smoother let out and blew the tires off. Went back on the same psi and went back to the previous launch rpm, still didn't get a good pass out of it. It was VERY particular to all of the inputs, that's for darn sure.

I went ahead and ordered the RXT, and will be going with the bias ply's. All I have to do now is get all of it on and in, and get Gary to send me his old GTO spares lol

I hope to be able to report some new and improved results in April.

HardcoreABN

I love mine! I can't wait until I get it back to the track with a built 3rib and 3.90s in a few weeks.

robz

Good stuff. The car will want to spin more with the new clutch so you will need to figure out a launch technique that works. We can help.
If you can get some videos from the side during the launch that includes the entire car we can give you feedback.