LucidBD

then why would a 5 speed be any different from a auto.
it would be the same damn thing... i wanna shift where i wanna shift in a race. im not sayin im gonna go out and pin the needle to 8 every time. i just hate how it shuts me down...the engine IS NOT gonna blow if you go over the limiter GET OVER IT!
i didnt buy my TC to just drive it like some old fart or some safety **** kid. i have upgrades coming and this is one thing i can get outta my way.

some of you people are Awsome and really cool and helpful.

other are just here to make things ruff and condratict EVERYTHING.

mrbridge

That's the point. If everyone was helpful and didn't challenge, then you'd never learn or really think. But, oho! if someone says no, the natural reaction is to say "why?" and thus you learn!

So the helpful versus the contradictory are all helpful, just not how you'd expect.

jmiller20874

No need to get all testy and what not. I didn't come to flame. If you plan on redoing your internals to raise your redline then so be it, you have a valid arguement. If you're not doing internal work, then there really is no reason you should be wanting to go past redline. No you may not blow your engine initially, but you are doing damage and it does add up. Do you have auto or 5-speed? If you have auto then how are you shifting? If it's 5-speed, shifting past 6.3K rpm's is not good and you're missing your power curve which can give you a slower time not a better one.

I'm not here to lecture you, I'm just giving you and anyone else who might be considering getting rid of the rev limiter because they are trying to get all Fast and Furious and blow the redline of their engine, something to consider. Just don't be coming on to the General Discussion forum saying "I blew my headgasket". One last thing, hitting your powerband at it's optimum point is not being an old fart nor is it being a safety **** kid, it's just the way you should be shifting to go fastest.

SupaWhiteTc

Why the hell would you really need to go over 130MPH?? I took my Celica GT-S to 145MPH and there is really no point. Unless you hit the limiter in the 1/4 mile why take it off there is no point.

tc05

what is the redline on the Tc, i hear its around 5900 just want to know, if its around there do you think we are at a disadvantage when it comes to ther vehicles like teh mazda3 or teh celica with a higher redline

jmiller20874

The redline is 6.2K and the rev limiter hits at 6.5K. The 5.9K limit you speak of is the speed limiter in 5th gear @127mph. In stock form, the tC wouldn't benefit from having a higher redline since it hits peak power at around 5.8K, anything past that is pointless.

Now say you go turbo or do some other heavy mods that could greatly alter the powerband, then as long as the engine hasn't stopped producing power, the redline could be raised if the necessary internal work was done to support the added strain.

Joe_Dezod

My Apexi computer continuously logs me hitting 6580-6589 rpms whenever I hit the rev limiter. I've cleared the ECU and Apexi computer numerous times and get the same results, so our real rev limit is 6500. The Apexi tach shows identical rpms compared to my stock tach at low-high rpms so I know it's accurate.

On another note though, I still haven't been able to get the speed limit cut to work. This is due to the advanced braking control system that uses the speed sensor. The ECU isn't wired like most ECUs with a regular speed senspor pin, it goes through a second computer first.

Time will tell. We need a Helms manual or a Scion service manual haha..

pureXtC

just to make another comment on shifting past limiter its pointless to shift past ur power band and u could also cause valves to float so why bother

raamaudio

I will really want to get rid of the speed gov when we are finished with our mods plans so will be looking into it;)

as per one post, I do not believe any autos have syncros, none I have ever heard of in my nearly 53 years

Rick

Joe_Dezod

shifting where your stock rev limiter kicks will not damage anything... they're very conservative with their limitations.

also... power band is something a lot of people don't fully grasp. If you redline then shift, you fall into a point where you're still making decen HP. If you shift right after your peak torque, once the clutch engages your rpms are so much lower that your torque goes down even more than it fell off at the higher rpms.

I could explain it more, as I'm sure some pople know. Basically at the track, max out 1st and 2nd... After that, learn your shift points, so when you shift you're still at optimum torque. It's an average that you're looking for.

raamaudio

I have to pretty much agree. First and second are fairly low geared and you go through them quickly, third is a bit of a jump so it takes longer to pull through and you can deffinately feel the power dropping off at higher RPM's, I shift early into fourth, not real early.

If you really want to go fast, shift 200 RPM or so early from 1st to second but do not lift the throttle, keep it nailed, same to third gear, it will supprise your with how hard it hits(except into second as fairly heavy wheel hop can result, motor mounts will fix that) By shifting slightly early you help keep of the rev limiter.

Rick

boostedscion

thats interesting

Shannon

shift!

pureXtC

hold on so ur saying to shift while u have the gas pegged down the whole time thru 1st and 2nd

djct_watt

goodbye, clutch!

jmiller20874

What's that smell?

madpb

After reading this thread its seems to me changing the gearing would be a better thing to do. Yes I wanna go over 126 mph, I chased a Solara and he was cruising way faster then I could.

raamaudio

Some of you guys are embarrasing yourselves;)

Making fun about what you are unaware of, lol!

Anytime you slam gears you are adding more wear on the whole drivetrain but leaving the throttle down if alot easier on the tranny and engine than lifting while slamming gears.

If you are serious about going fast, often, you will need a better clutch anyway, it is an expendable replacement part, the tranny and engine are not. Only bad thing, it is alot of work to install a new one but not costly for us that do all of our own work. Not lifting will not have that more effect on the clutch and if done properly may be easier on it, depends on how well you drive.

On another note: changing gearing will require changing the speedo calibration possibly, I have not determined where the reading is taken from just yet. Either way, the speed governor will still be in effect.

One idea I have is a circuit inline with the speed sensor to the ECU, once a preset value is reached, it limits the pulse count to say a 125MPH reading to the ECU. This would enable you to go faster but without a speedo changing with the velocity of the car past 125. I do not know if it would efffect any other parameter inside the ECU, Toyota has that pretty locked down. Sure wish I could get some schematics of the ECU!!!! I would adjust the rev limiter up a bit and delete the speed gov completely, yesterday

For now, the engine does not breath well enough in NA form to need a higher redline, under boost that would change a bit, even without a porting job. Ported would really awaken the top end. I am more concerned with bottom to midrange power, higher RPM would be mainly for not having to shift as often during autocross runs.


Ok, I have work to do, have a good day!
Rick

djct_watt

You shouldn't be slamming gears. . . my brother worked with Jackson Racing (a race school), and you don't slam gears. You should be shifting perfectly, matching revs on downshifts, and lifting off the gas on upshifts. It's not your drivetrain that wears out; it's your clutch.

djct_watt

Want a higher top speed, get a taller wheel profile. . . that changes your final drive.