Chuck!

Im going to Norwalk this friday assuming the weather holds out. Right now its preidcted to be between 54 and 44 degrees.

As you can see from my sig, my times suck ***. The 60' or ET are not there, but more importantly to me the MPH isnt there. I know this car should be trapping at 95+ mph, but the mph is now where near that. 92.81 is not where I want to be at all. Its down right embarassing, honestly.

So Im asking you guys for a little help. I dont know a lot but I can sure as hell follow directions.

Heres my best run break down from about a month ago:

rt: .597
60': 2.412
330: 6.645
1/8 et: 10.132
1/8 mph: 71.08
1000' et: 13.027
1/4 et: 15.500
1/4 mph: 92.81

I also posted my winaldl log of this run. It was made with about 22 psi of air in the rear tires, as I had tried 26 and still wasnt hooking. Granted this is without posi.

I was told my o2 readings are high, and I can see my tps is only open 94.4% and Ill try to get it to open all the way before I go.

I have no idea where my timing is, I got pissed off and just keep turning it until it started to ping. If I pull my fuel pressure down can I get away with more timing, or should I just leave it where it is?

Thanks for any help you can give. Sorry for the lenght of the post, but I just would like a decent time before the track closes for the winter.

Keep in mind that Im driving my beater home from school tomorrow, then getting in the RS and going directly to the track. I really dont have time to change anything at home, so any launching techniques no a non-posi rear end would be appreciated, or help with my o2 reads or anything. Tire PSI? Thanks guys.

http://homepages.udayton.edu/~kulchacs/91302_3.txt

irocz383

Hmmm... A set of 3.73's would definatly help in all area's.

My 305 runs 14.5's all day long at 94 MPH. A couple things that might help are...

1) Tire preasure = I run my 255/55/16 at about 20 - 25 PSI
2) Burn out = Don't do a smoke show at all. You'll end up greasing the tires and it will slip worse than if you didn't do one.

The key is to get them spinning until you just start to see smoke coming out. Then let go of the brake and let the car pull onto the launch pad. Once oyu here the tires bite let off the gas and get ready to stage. You'll know if you're tire are sticky enough then. You'll hear what sounds like a loud chirp / screeching sound.

3) Make sure the car is as cool as possible but hav ethe exhaust hot enough so the O2 works properly.

There is probably something I'm missing but that should help a little. At least with the 60' times.

VortecZ28

You have the vortec heads on your 305 if I remember correctly
Vortec's don't like a lot of timing, thats the general consensis on thirdgen.org. It's also what I found out at the track,
I started out with a timing similar to yours, right on the edge of detonation.. my harmonic balancer isn't lined up so i don't know what inital timing that was, but I would quess about 15-20*, I turned it down and gained mph, I kept turning it down until my gains stopped. probably 10-15 degrees total and gained 4mph.

Take a timing light, start at 12* and keep going lower and see if you gain anything
my top mph is 102 now with a slower ET. I bet my timing is 5* initial and 30 total

those gears are hurting you I think, but 96mph should be np the way your car sits. Whats the elevation at your track?

Go buy a weed sprayer, fill it with water and spray down your engine after each run, ice bags work too, and don't idle your engine in the staging lanes until race time. keep that intake cool!

How heavy is your car? weigh it on your way to the track, you might be making the power, but a little bit overweight

goodluck man!

91RS5speed

You might wana run with a full tank of gas to help get that 60 foot down. You need to work on getting posi next. That will make a huge differance in how it lanches.

Chuck!

I got the posi 3.42 rear end, just aint in yet Not doin any good sitting in the garage.

The car is stock weight, full of everything including spare tire. I'll def. try the timing thing, thats very interesting. Norwalk's elevation is just about 900 feet if I remember right.

Thanks for the responses guys

VortecZ28

Do yourself a favor and weigh the car.
weigh it at a few different scales if you can, it's good info to know!

slimdawson

I agree with the timing. Keep adjusting until you lose mph. If you lose mph after the first adjustment, go the other way next.

Also, if you are looking for more timing, run richer. That will keep the charge cooler and stave off potential knock that could result from a leaner mix. So keep the fuel psi up. Also adjust that up or down to get hp.

My car weighed 3660 with me(170) in it, a full tank of gas, and two tens in the back when it was stock so I figure yours would be close to that.

I was able to cut 2.3x with my stock tires(245-50) and the 2.73 gears, so you can probably bring that down. If you go too low on radials the contact patch actually shrinks, so lower is not always better. I aim for 25 and that seems to work best. Also, how do you leave? I would hold the brake with the left foot, put the engine about 1500 and then let off of the brake and EASE into the throttle. Sometimes when you can't hook it, you have to be patient. Also, overinflate your front tires for less rolling friction. Use the max air psi indicated on the tires or more if you want.

Hope you get some times you like. Btw, I checked out your website and you have a nice looking car.

Later, Mike

IROC5.7TPI

Heres my $.02....

First off the 60' SUCKS! You definitely need a posi with a 3.23-3.42 gears. I wouldn't go more than that, it just wouldn't make sense to give up gas mileage and reliability for a few .01's of a second.

The next issue is (as mentioned) timing. When the knock sensor hears detonation it will change the spark tables to compensate, so what it really is doing is going into knock retard and losing power. Whenever you make a timing change that ends up going into knock retard you should reset the ECM by disconnection the battery and having it re-learn. As mentioned above, a good base timing to start at would be around 10*-12*.
What I am really having a problem with is your 60'. I can pull 1.969 on a bald XP2000Z. Of course track conditions vary from track to track, but i know for sure your traction sucks to no end

Also you may want to get a higher stall speed torque converter. I know I picked up .3 in the 1/4 with that mod alone.

Please post results