89formula#1

ok guys i have a weird questions for ya, When i get on it i usually shift at aroudn 4700 cause it makes the loudest chirp when i bang 2nd, now i figured since it doesn;t chirp at like 5100 i am not making as much power. Now I started shifting at like 5200 and it seems to pull harder and make more power and generally be faster,now does this whole chirp logic work or is it retarded. also i have a beat pepbys clutch and i think mayeb its slippin at the higher rpm and not lettin me chirp. wut do u guys think?? thanks in advance

AJ_92RS

It's not where your RPMs are when you shift OUT of a gear, it's where they end up when you put it into the next gear.

Peak TQ usually happens at lower RPMs, so by shifting sooner, you're putting the next gear (2nd) closer to peak TQ, therefore applying more "BANG", and more "CHIRP".

Make sense?

89formula#1

That makes complete sense, so say my car makes peak horse power at 5500 and peak tq at 5000 then where shoud i shift? at 5500?? also i guess thats why gears make such a difference right? cause u get back to that BANG quicker

84'Camaroboy

AJ_92RS he knows whats hes talkin about!......juss to add somethin my little brother downloaded a streetracing vid of a 4th gen ls1 chirping them into 4th gear!?....what kind of power is this guy makin?

89formula#1

my buddy is runnin liek 14.2 in his stang and hes got 3.73;s and hes chirpin 4th every once in a while so chirp doesn;t alwayts mean power, even thogh his car feels liek its a 12 secound car cause its all gears

zippy

most tire chirping is done in cars driven by people that can't shift fast enough. first of all, lower rpm=lower speed also. the lower the speed is, the easier it is to break the tires back loose. lower rpm shift also put's it more in the grunt part of the torque range causing the "chirp". a properly driven manual might spin a touch going into second, but that's about it. a Z06 will "chirp" the tires in first through 4th, but when powershifted, it'll only spin a touch going into second and that's it. the other issue is slower shifting and lower rpm unloads the suspension more allowing traction loss easier.

AJ_92RS

If that's true, then my automatic TH350 and TH700-R4 in my '72 Camaro and my '92 Camaro must be some slow shifting *****.

They'll BOTH chirp them going into second, AND going into 3rd.

Do you know how I can speed up the shifts anymore than the shift kit that's in them?

Wait a second. According to you, the shift kits I installed must have actually SLOWED my shifts. Neither car chirped the tires until I installed the kits.

That's it. I'm gonna sue Transgo and B&M!!!! They told me they made the tranny shift quicker.

FirebirdTA

hey at least u guys can chirp your tires. my one wheel wonder 152k mile lg4 wont chirp. hell it wont even burnout.

zippy

aj, the question was referring to manual's. automatic is different. that's not a so much a power issue with an automatic as it is a large gear seperation that commonly causes that. most good manual trans cars have close enough ratio's that the small amount of clutch slipage takes away the chirp, that is unless your tires suck. if you go to a track and watch the big boy's run you won't find much of the the chirp going on with manual or auto. my truck does it's share of making noise on shifts also with the shift kit i use and billet servo and isn't terribly fast.

AJ_92RS

I guess I have to be terribly blunt.

You're wrong. Tires chirping, whether it's a manual or automatic, IS NOT caused from
I.E., you're saying it's caused from a shift that is TOO SLOW.

You're wrong. It's caused from people (or auto trannys) that SHIFT TOO FAST!!!

I was referring to MY car because there aren't too many people (and none that I know) that can shift as fast as an automatic transmission with a shift kit installed. Based on what you said, the quicker shifts should prevent chirping. You're wrong.

I'll say it again, just in case you didn't understand ...

YOU'RE WRONG!!!!

zippy

no, you obviously need a better understanding of an automatic. there is more to a shift kit than a "qucker" shift. in a auto car you have a torque converter multliplying torque which is why they dyno more at the wheels for torque. the reason there are accumulators on auto's is to soften the clutch/band engagement and allow more slip to occur. installing something such as a larger servo for example isn't changning how soon a shift occurs from the time the governer calls for it, but how long it takes for full apply of the band/clutch. in a manual this would simply be the same as releasing the clutch slower on a shift as it will grab at the same point but allow more slip to occur before full apply. if you like the harsh shifts, take and lower your shift points around a 1000 below what you'd shift at for racing. you'll find it chirps much harsher, but not because you're shift was that much quicker. when it comes to a manual trans car, shifting faster allows the weight transfer to stay in and keeps the speed higher which both in turn makes tire spin less likely. with an automatic, you can have as quick of a shifting trans as you'd like, but shift points, stall of the converter and cluch/band material will have the effect of your "chirp" on shifts.

zippy

maybe i'll try and explain the manual trans. part a bit easier to understand. if driver a, an unexperienced driver is in his rwd manual trans car and makes a shift at say 6k, he'll push in the clutch at the same time as letting off the gas causing the flywheel to slow down and the engine to deveolop a large vacuum in the intake. next in the process he pulls for the next gear, stabs the gas pedal to the floor again causing a spike in the torque since the high manifold vacuum will quickly draw in more air than just having been left at wide open and the clutch is released. now with the flywheel mearly just coming up to speed the clutch grabs sooner, the speed has now dropped a touch due to how long it took driver a to shift, and his torque spike along with that will cause the easiest thing at this point to slip which is likely the tires. at this point the tires also have lost the advantage of the weight transfer they were just taking advantage of and cause the "chirp".

now driver b take the same car, pushes in the clutch with the gas pedal still on the floor causing a small spike in rpm, but with no load a slight torque loss. as anyone knows, the higher the rpm the more slipage will occur. he's going to grab his next gear much sooner than the driver a. loosing little to no speed, having a touch more slipage on the clutch from the rpm difference, and little to no weight transfter loss on the tires. this in effect will give much less of a chance for tire spin. remember if this can't be compared to an auto since clutch engagement was the same. neither of the two drivers are easing the clutch out after shifting. both will be allowing the clutch to slam back into the flywheel with roughly the same amount of time in release of the actual clutch. this is the issue auto's deal with, how long it take's for the clutch/apply making use of the new gear. with a manual trans, whether it's an amature shifting or very good driver the clutch on the shift is released just as hard. even with driver a moving shift point up a touch higher say from 4500 to 5500, he now has a higher vehicle speed to deal with making any tire spin more difficult, the engine loses more of it's spike in torque as it's coming up to it's higher (longer to get there) rpm as well as the engine likley getting further from peak torque, and now with everying spinning faster the clutch takes on a bit more natural slippage before it locks in.

Jaymesholmes

That is correct. Chirp with manual only means inexperienced driver or driver who thinks chirp means power.

All you have to do is create vacuum by completely letting of gas during your shift

pretend like you purposefully are letting off gas and letting rpms drop all the way to idle before dumping the clutch and then next think about stabbing back on the gas before another complete second rolls on by and you hear all that extra "power" chirp the tires.


On an auto it means a short shift occurred.
That means a request to full slip the torque converter for the max the rpms during acceleration has been denied.




pretend liketo hit gas at same time as
wait till it's at idle rpms

and