Bay Area User

so, yesterday i took the car to the track (infineon raceway)
We had a crazy headwind and after one run, the track officials decided to shut down the 1/4 mile and just run the 1/8 mile.
It was getting too Dangerous. Dirt was blowing on the track, etc..
Most of my friends, who are consistent drivers were running a couple of tenths behind their usual time. so i'm taking this times with a grain of salt.

I drove with the traction control ON, pumped the front tire pressure to around 45, initially lowered the rear tire pressure to 25 (street tires) but after getting error messages on the console, i decided to pump them to 30 -error message went away.
Will the computer affect performance if it has error messages(malfuntions)?

So, got a 12.85 @ 109mph. With a 2.0 60 ft.
Only got one run.. so i'm sure it can go a little faster. Decided to take off after they shut the 1/4 mile track, no point in beating the car for only 1/8 mile.

I felt the traction control kick in a few times.
there was a huge lag between the time i stepped on the gas and when the car launched. my reaction was horrible, .3 that's bad considering that i get consistent .04s-.03s with my cobra.


So.. yeah, at least it was a 12 sec run. MPH seems kinda low. How do this numbers compare? what's the usual range for this cars?
thanks.

ROCKETW19

ya your MPH was low and you 1/4 time was realy slow. not sure how track prep was and if the wind was that bad these numbers wont even count. you should come to sac raceway next time. you will get more runs in and they are very cool as far as rules. id just chalk that day up to pratice and wait for better conditions to realy see what she can do.

Bay Area User

what seems to be the normal mph range of e55s?

Do any of you guys drop the tire pressure on the rear at all?
I have a malfunction now.
It says "reactive tire pressure system" or something like that.
when i check the pressure they all read 40 psi. So i don't know what that's about...

Can't wait for next wednesday. hopefully conditions will be much better.

AMGcrazy

I don't know what your altitude is there (I'm sure Juicee will chime in), but bone stock I ran consistently 12.5X @ 113 with a 2.0X 60 ft. With a 1.8X 60 ft. I ran 12.3X @ 114. That was about 500 ft above sea level.

So I'd say your time and MPH are somewhat slow, but with a headwind and some altitude, you might not be too far off.

ROCKETW19

if i remember correctly its like amgcrazy said around 114mph and 12.4
wht would you drop tire pressure on a street tire? i would only drop pressure on DRs.
is it real far from where you are at to come to sac?

Bay Area User

It's about a 2 hour drive(with traffic).... just doesn't make driving that far out attractive on Wednesdays..

From experience with Other cars.. a little lower than normal pressure on street tires help with tire spin a bit..
I would get 1.9s with street tires at say 27psi as apposed to 2.0s at 30 or so.
It seems much easier to cut good 60s with this car (maybe cause it's an automatic) than with 5 speed cars..

I might get drag radials for this car later on.... i'm waiting for et street to come out with the 18 inch drag radial..

First i need to figure out with my mph is low...
Sac is a much faster track than infeneon. I remember i was stuck in the 12.3s with the 03.. and on my first visit to sac i dropped almost two 2 tenths.. the mph seemed to stay consistent though.

I remember feeling a hard hesitation when it went to 4th gear (or whatever the last gear before finishing the 1/4 mile) it was significant enough to be easily noticed. car slowed down right when it shiften and then it picked up again?
Could it be the dreaded i/c pump going out?

Hotrod-Realtor

[QUOTE=Bay Area User;2419413]what seems to be the normal mph range of e55s?

Do any of you guys drop the tire pressure on the rear at all?
I have a malfunction now.
It says "reactive tire pressure system" or something like that.
when i check the pressure they all read 40 psi. So i don't know what that's about...

QUOTE]

This is probably not your case but my wifes Dodge Charger had an error code with the tire pressure monitor once. I checked all four tires and made a slight adjustment but the error message returned. I took it to the dealer who fixed it by filling the spare to the proper PSI

Bay Area User

[QUOTE=Hotrod-Realtor;2419550]

really? could be.. haha.


GUYS two questions!
1.-what does Tire Pressure Monitor reactive mean??
2.-Do you guys race with the traction control on??

juicee63

[QUOTE=Bay Area User;2419560]you need to reactivate your tpms. Use your menu buttons to turn on tpms. (steering wheel) . I would ignore the warning lights from the low tp. You can go as low as 15 psi on a dr and 23-30 on the street tires

MRAMG1

[QUOTE=juicee63;2420208]Hey Juice:

Just FYI, You can go even lower on street tires, I know as I have done it.

I have autocrossed on as little as 18 psi in the rear, and don't even hesitate to do this at the drag.

Just remeber to pump them up on your way home

See yeah

chiromikey

yeah but i'd be willing to bet you're hurting performance by doing so.

MRAMG1

I'll take ANY bet

Seriously, My stang didn't get in the 12's till I droped them, running a 275/40/17.
And for autox, it was THE ONLY WAY to get more steering, ie over steer.
As far as performance, what will you hurt? You gain a better 0-60 foot time, which is the WORLD in dragging

Try it, you like it

See yeah

chiromikey

i've tried it and i'm speaking from experience when i say dropping psi that low is not going to help your launch. as far as i know, i've got one of the best 60' times for an e55 on pure street tires...19" tires at that. these cars are not direct comparisons to stripped down mustangs.

MRAMG1

Not arguing here my friend, I have tried it on ALL cars and it works for me, ie lower 0-60 foot times/better e-t. If it didn't work for you, so be it.

By the way, my stang was a full street car, albeit fully caged, with a trunck full of stereo goodies.

Anyway, I say potatoe, you say potato

See yeah

WayneE

MRAMG1, it's been my experience with radial street tires that they don't like the really low pressures. While you were able to produce your best times with them, it may have been coincidental and not directly related to your tire pressure.

You'll get the best traction out of a short sidewall high speed-rated street tire with a short burnout (1-2 seconds) to clean any debris/rocks off the tire and tire pressures in the 24-26psi range. If you do a burnout on a clean surface, you'll see a good contact patch at those pressures. Anything less and you're not putting all the rubber to the road.

YMMV, etc

To the OP - my stock E55 runs 12.1-12.3 at sea level on street tires in a variety of weather conditions. Trap speeds from 114-117mph.

Bay Area User

man, all this talk has gotten me anxious to hit the track again.
I'll be there next wednesday.
QUESTIONS

Do you guys have the traction control on or off when drag racing?
thanks

WayneE

I usually run with ESP off. Sport shift, manually shift to 1st gear, comfort mode suspension, let the tranny shift itself.

MRAMG1

Hey WayneE:

You are correct that if you under inflate the tire too much, espically if the rim is undersized to begin with, you will loose size of the tires contact patch. Simply put, the tire will be riding on the outside edges only.

However, if the tire is properly matched to the rim, you can run less pressure as the tire will flatten out at first and then ballon slightly under wheel spin/acceration, and it will MORE than make up the differnece.

Hey, I am only trying to relate some experiance that I have seen work on various tracks, drag, autox, road circuits, etc.

Give it a try, as you have NOTHING to loose my friends

If I am wrong simply inflate them again, If I am right, well, you get the point.

See yeah

PS: your spot on about street radials doing a SHORT burnout. I always love seeing a guy absaolutely KILL his street tires in the waterbox, only to have them light up like a christmas tree when he lines up at the lights

Bay Area User

If you are on S mode. and downshift to first manually, will it shift automatically still?
I tried this on the street and took it to about 4k and the tranny would not shift into 2nd by itself...
I'm afraid of taking it to redline and not have it shift or something...
or will it shift once it hits redline?

What i did at the track was, had it in M 1 when i span the tires to clean them up and hit S after staging the first light....

thanks.

AMGfan

If you are running drag radials on stock rims...

Do you avoid the water AND do a quick burnout?
Lower the PSI to around 20 on the drags?

MRAMG1

Hey AMGfan:

NO drag radials REQUIE a specific time in the watrer box, ie burn out. Which ever brand you bought, they will give you SPECIFIC directions as to HOW LONG you should heat them up. DRAG radials are desiged VERY different from stree tires and ABSOLUTLY REQUIRE HEAT to be effective. EACH brand is different so read that little sticker that came on the tire please. If memeory serves me right, BFG says about 10 seconds in the water box, I think so don't kill me on this one guys.

AS far as PSI, 20 is a good starting point, but again READ the instructions they are different from brand to brand, Hoosier to BFG to Goodyear, etc, etc. Some even give differnt pressure for different width rims

See yeah

AMGfan

I appreciate that...the Nitto 555R on stock rims are in my garage and I will do read accordingly. I plan to actually go to the test and tune night for the first time just to watch and get acquainted with the surroundings and protocols.

One last thing (not really)...what is the usually time between runs is recommended?

MRAMG1

Hey AMGfan:

Cool down time should be about 20-30 minutes. Keep in mind that usually there are SO many cars on test and tune nights that it will probably be ALOT longer between runs.

Oh yeah, ICE on the intake boxes and blower works VERY nicely. Just don't forget to put a wet towel down first, or the bag will melt to your blower. Can you say OS

Good luck, and lets us know how you do

See yeah

WayneE

Start @ 20psi. Drive around the water box. Back into it to get a little water on the tires, then pull forward out of the water. Hold the brake and start feeding in the gas aggressively to get the tires spinning. Apply JUST ENOUGH BRAKE TO HOLD THE CAR IN PLACE. Don't mash the brake pedal. Also, don't just floor the gas - just feed in the throttle quickly to get them spinning.

So now you're standing still and the tires are spinning. As the tires heat up, they'll begin to drag the revs down - should take just 2-3 seconds (you're not John Force) - as you feel the tires begin to bite, let off the brake and gas and roll out of the burnout area.

Quickly get into the brakes and come to a stop. Check the starting line for the "groove" where the fast cars have been running. Get lined up there and stage.

You're all set!

higginsbeach

Hey Wayne,

Great description on the burnout sequence. What mode are you in...S or M. Never noticed a groove before so now I will look for it after my burnout but before I stage.....