"chirping" tires on 1st to 2nd shift with RPC chip

[darebren]

it seems I'm so close to hearing a chirp from the tires on a decent throttle from 1st to 2nd gears. In the rain, they definately spin.

I was wondering if wider tires with a max performance tread would cause the "chirp" to be heard more. Maybe a high performance wide 255 tire would chirp because there would be less pounds per square inch where the tire meets the road?

I'm going for that "chirp" effect.

Also, maybe after engine loosens up it will become more pronounced too, only 2500 miles so far on it.

[LincMercLover]

I get second gear scratch with mine when manually shifting, and I'm bone stock...

[prchrman]

DITTO...

[darebren]

without the chip, i could get 2nd if manually shifting at about 4k rpm's.

The chip shifts it around 3.5k under fairly hard throttle, no chirp.

from dead stop can bark tires, but not lay patch by any means. I think I got the slow one.
:help:

[LincMercLover]

1st lock in, RIGHT at 6000 RPM's, click 2nd, CHIRP!

I get her to break loose sometimes from a dead stop, depending on the pavement.

I wouldn't expect any chirping when not under WOT though. If you think about it, the scratch isn't a good thing, cause you're loosing traction for that split second.

[TripleTransAm]

Originally posted by LincMercLover
If you think about it, the scratch isn't a good thing, cause you're loosing traction for that split second.


If the tranny shifts are crisp and firm, the driveline shock on an upshift may result in the tire chirp we're speaking of. Otherwise, the driveline 'shock' from the shift is soaked up in tranny clutch/band slippage. My gut feeling is that I'd rather lose traction on a firm upshift than have the tranny soak it up in wear and tear.

About losing the rear end on a launch: happened to me the other night, really surprised the crap out of me. I had taken it easy for about 1000 miles and was surprised at the improved launch. Traction control was on, I wonder how bad the wheelspin might have been if it was off.:up:

[SergntMac]

Just my .02c in review of some old topics.

The MM is rather stiff brand new. As you add break in miles, maybe up to 3K or so, she begins to loosen up and show more performance. If you're going to stay bone stock, your best performance is produce by manual shifting.

The power in the car is high in the RPMs, if you are shifting out at 4000 RPM, you're leaving the dance floor before the music ends. However, after 4000 RPM, things wind up real fast, so, watch your red line.

If you want to show off or have fun, stay in your power band (3500-5500 RPM) as much as you can. Down shift to second for rolling 30 MPH punch that will leave an unforgetable impression. If you leave it in drive and hammer down for WOT, you'll lose a full second in mechanical reaction time, and (depending on your speed) waste time (maybe a race too) by downshifting all the way first gear, just to shift out of it.

Experiment with your tire pressure. 35 pounds will give more "road feedback," you'll feel more cracks in the pavement. But, stiff tires are easier to break and spin more, if that's what you want. Stiff tires also reduce tire drag, you'll coast much longer. 30 pounds of air will make them harder to spin, but you'll appreciate the stickiness in a hard turn, or under severe braking.

I suggest you start with 40 pounds and a good pressure gauge. Take notes and reduce pressure a pound at a time. You'll find what works best for you, and you'll find different setting are suitable for different driving challenges. Write 'em down, and adjust the tires for what you want to do. Don't go under 25 pounds, you'll lose all handling and traction in the corners and under severe braking when the sidewalls give in.


Keep in mind too, that breaking the tires loose is a nice sound effect, but isn't good for winning a race, even the short ones across an intersection. Leaving...Is what is most important, being gone now.

Burning rubber, is just burning rubber. When the cops hear the squeal, what do you want them to look at? A black heavy duty 4 door? Or, the lime green roller skate with a 4' rooster tail and a chrome spitoon hanging from the bumper.

This may be a hulking 4200 pound gorilla, but a fine tuned Marauder with just a few "right stuff" mods, is an impressive automobile. No one will get, or stay, in front of you. Skip the side show, be the main event...IMHO.

Cha-ching...

[ghost]

Increasing the transmission line pressure via the chip is an electronic way of doing something that's best performed mechanically. If you want to bark the tires, install a shift kit.

Would a shift kit void your warranty? Would a dealer install it? It would be silly if it did since it would save on clutch pack wear and actually extend the life of the trans.

Few things are cooler than a big, heavy automatic transmission car barking the tires on the 1-2 and 2-3 shifts. :D

Or do they not even make a shift kit for the MM? :confused:

Eric

[Paul T. Casey]

After a while of driving and learning this convoluted tranny and all her quirks, it is possible to make that chirp you speak of happen with your right foot while the selector is in the D position. You get it into 2nd, and when she's ready to ****ft to 3rd, dance the pedal. (a quick on-off movement.)

[SergntMac]

Originally posted by ghost
Would a shift kit void your warranty? Would a dealer install it? It would be silly if it did since it would save on clutch pack wear and actually extend the life of the trans.

Likewise arguments exist for all the modest mods we chat about here. Not only to they combine to build a kick azz car, every one of them reduces fuel consumption, improves emissions, lengthens the life and duarbility of the overall car, an so on...yada, yada, yada.

Every one of them will void a warranty if you get caught.

Every one of them can be ignored by the sympathetic SM.

Logic is not part of this scenario.

[Thomas C Potter]

I'd expect wider stickier tires will reduce the 'chirp' you're after. And as stated, tire pressure is certainly a factor.

[LincMercLover]

Sarge,

Your words are gold, but there's a few things I think you may have forgotten about a stock MM. I believe the best times will come from letting the tranny do the work with OD off. And as for dropping second for a 30 roll, you'll get left in the dust if you do this. Trust me, I've tried it racing my buddy's Monte. He asked me afterwards, "Were you even giving it gas?!?!" First is the best place for 30 rolls, just don't hit first if you're doing over 50, as that's the limit of first gear.

And as far as ghost's comment on shift kits, yes, they do prolong the life of the tranny, IF you choose the right one. I've seen two turbo 350's bite the dust because the moron's were riding around town with Stage 1 and 2 shift kits. Street/Strip means exactly that, and more isn't always better!

[RF Overlord]

Sarge on ricers:
When the cops hear the squeal, what do you want them to look at? A black heavy duty 4 door? Or, the lime green roller skate with a 4' rooster tail and a chrome spitoon hanging from the bumper.

BWAHAHAHAHAHAHA... ROFL, Sarge!


Sarge on dealers vs. mods:
Logic is not part of this scenario.

Truth, yo...

[SergntMac]

Originally posted by LincMercLover
Sarge...I believe the best times will come from letting the tranny do the work with OD off. And as for dropping second for a 30 roll, you'll get left in the dust if you do this. Trust me, I've tried it racing my buddy's Monte. He asked me afterwards, "Were you even giving it gas?!?!" First is the best place for 30 rolls, just don't hit first if you're doing over 50, as that's the limit of first gear.

I won't doubt you, LML, my recall of bone stock performance is fading. And, Though it was on my mind, I forgot to mention to keep the OD off, thanks for covering that.

If you'll excuse me now, I'm working on page two of my reply to another thread...LOL

[ghost]

Originally posted by LincMercLover
And as far as ghost's comment on shift kits, yes, they do prolong the life of the tranny, IF you choose the right one. I've seen two turbo 350's bite the dust because the moron's were riding around town with Stage 1 and 2 shift kits. Street/Strip means exactly that, and more isn't always better!

Agreed, although it would be interesting to know exactly what parts broke in the TH-350s. If you're going to go beyond Stage 1 you should beef up the internals if you want it to last longer, IMO.

However, a Stage 1 kit is the lowest setting and would be okay on the street for a daily driver.

Mine, btw, is set up Stage 3+. :D It'll chirp the 1-2 with half throttle. Fun, sure, but I beat the hell out of my drivetrain. Just ask my wallet. I play and pay and that's expected and accepted. But my issues are rear-end related rather than trans related.

Eric

[looking97233]

After reading this thread, mabye I got the "gem." You know the one that for unknown reasons just is a little quicker? Who knows, I need to do dyno runs. I get more than just a scratch on auto 1-2 WOT@6k rpm or manual 1-2 at WOT above about 4800 rpm. On dry pavement she kicks her butt out about 6-12". Followed by the throw you back in the seat for about 1/2 sec. Everybody else's cars don't do this?

[LincMercLover]

Go away, no one wants to talk to you... :lol:

How many miles you have on her?

[looking97233]

8050 as of today, big difference from new.

[JamesHecker]

Mine has 12,000 on it and doesn't do that, looking. I still love it though!

I also really enjoyed this thread. Sarge, you're a hoot.

[looking97233]

Humm, when I get her back from the body shop, I'll see about getting a dyno pull, mabye a trip to the track.

[Mike M]

Mine does, 5k on it now, it hits second and the tires loose traction for a split second and if steering wheel isnt straight it kicks out a bit. These tires don't seem to make noise like some tires do.

[ghost]

Originally posted by Mike Mielnicki
Mine does, 5k on it now, it hits second and the tires loose traction for a split second and if steering wheel isnt straight it kicks out a bit. These tires don't seem to make noise like some tires do.

Might be the pavement too. I like fresh, black asphalt best. :D BIG NOISE. Some pavement I can do a burnout on and hear no complaints from the tires at all, just motor & exhaust. That's no fun.

Also, warmer temps help.

Eric

[drkknight196]

Mine has "chirped" from the first moment Dennis finished his work at WOT in "D" between 1st and 2nd. Of course, I have the 4.30 rear end.

[Hemlock]

I HAVE 23,000 MILES , PULLS HARD , BUT NO CHIRP .