Increase RPM's before fuel cutoff

[nocarbon]

I figured I would post a newbie question and lose any redeeming qualities I had from my "Driving Techniques" post a little earlier :) I have a 2001 GT and it redlines at 6800rpms as opposed to the GTS's 7600(?) . I realize the different internals and the lack of a second cam may keep my limit at 6800 forever, but my question to you is has anyone in a GT tried modding their cutoff point to 7600? I've been photochopping around with some dyno's and came to the (pretentious) conclusion that we may be able to gain about 15 HP from the extra 800 RPMs. Anyone know of how to do this? If it is even possible?

[vvtlikick]

The GT's horsepower is already declining by the cutoff, so raising the limiter would not increase the peak power (power would keep declining).

However, just increasing the limiter may make the GT faster, because you be able to stay better in the power band by revving higher before each shift.

If you want high rpm power for a GT, your best bet would be new cams (I bet you could see +25hp just from aggressive cams with proper tuning).

[t2000gts]

how related are the 1ZZ-FE and 2ZZ-GE? could you swap the VVTL-i head onto the 1ZZ along with the ECU? just wondering cuz some honda guys can swap VTEC heads around.

[nocarbon]

Originally posted by vvtlikick
The GT's horsepower is already declining by the cutoff, so raising the limiter would not increase the peak power (power would keep declining).

However, just increasing the limiter may make the GT faster, because you be able to stay better in the power band by revving higher before each shift.

If you want high rpm power for a GT, your best bet would be new cams (I bet you could see +25hp just from aggressive cams with proper tuning).

vvtli, since you live so close, why don't you just give me your GTS. Then I wouldn't have to worry about getting new cams.

P.S. Could you paint it silver for me?

[vvtlikick]

Originally posted by nocarbon


vvtli, since you live so close, why don't you just give me your GTS. Then I wouldn't have to worry about getting new cams.

P.S. Could you paint it silver for me? No problem....:rolleyes:

Seriously, I have respect for all '00+ Celicas except the GT-S Automatic (isn't fast, isn't cheap, it sucks).

[nocarbon]

Originally posted by t2000gts
how related are the 1ZZ-FE and 2ZZ-GE? could you swap the VVTL-i head onto the 1ZZ along with the ECU? just wondering cuz some honda guys can swap VTEC heads around.

I belive the 2zz has a larger bore than the 1zz. This would most likely prevent a head swap

[t2000gts]

Seriously, I have respect for all '00+ Celicas except the GT-S Automatic (isn't fast, isn't cheap, it sucks).

if fast and cheap are your requirements for a car, you got the wrong car. GTS 6-speed isn't fast or cheap, and it sucks. you should have checked out some LS1 f-bods.

or maybe...just maybe...you had some certain needs that the GTS 6-speed filled for you that an LS1 couldn't? (you should now be able to use your spatial skills and jump to the conclusion the GTS Auto might fill the needs of some other people who thank god, aren't exactly like you).

[vvtlikick]

Originally posted by t2000gts
how related are the 1ZZ-FE and 2ZZ-GE? could you swap the VVTL-i head onto the 1ZZ along with the ECU? just wondering cuz some honda guys can swap VTEC heads around. I don't know how feasible it is. But from what I know, the bare minimum I think you'd have to do to fit a 2ZZ head on a 1ZZ block would be:<ul><li>Bore 1ZZ block to 82mm (the GT-S's bore)</li><li>Replace Intake (incl. Manifold) & Exhaust (incl. Header) with GT-S pieces</li><li>Replace computer with reprogrammed/programmable GT-S computer (I doubt a stock GT-S computer would work with the larger displacement (1.933L) hybrid motor)</li><li>Additional work (oil lines for VVTL-i, etc.)</li></ul>

[t2000gts]

that sounds interesting. guess it'd be a helluva lot cheaper and easier to just buy a 2ZZ.

makes me wonder why toyota went with 1.8l for the engines though...looks like they could have easily gone with slightly larger displacements and recycled parts from the 1ZZ. or is the rest of the 1ZZ not built as tough as the 2ZZ? cuz i remember some guy from world racing saying the 2ZZ's tougher than a few of the honda powerplants he's seen.

[vvtlikick]

Originally posted by t2000gts
that sounds interesting. guess it'd be a helluva lot cheaper and easier to just buy a 2ZZ.

makes me wonder why toyota went with 1.8l for the engines though...looks like they could have easily gone with slightly larger displacements and recycled parts from the 1ZZ. or is the rest of the 1ZZ not built as tough as the 2ZZ? cuz i remember some guy from world racing saying the 2ZZ's tougher than a few of the honda powerplants he's seen. I might have missed a comment, but I thought the World Racing guy said that the 2ZZ was superior to the B18 in terms of head design, etc., not that it was tougher (and besides I'm sure the 3SGTE humilates them both, in terms of toughness)

As for the displacement question, The 2ZZ has a bore/stroke of 82mm/85mm, the 1ZZ has 79mm/91.5mm. So the 2ZZ has room to be stroked, and the 1ZZ has room to be bored.

But increasing the stroke of the 2ZZ excessively will harm it's rev potential, and also there's not much room to bore the 2ZZ. I think I'd go with no more than a 87mm stroke for the 2ZZ, because thats what the B18 Honda's use, and they're not harmed in the rpm department (although any differences in rod length between the two engines would also play a role in how much stroke could be used. Basically, a large rod/stroke ratio is good for high-rpm use).

[nocarbon]

Thanks for your help, I contact Mr. Draper to see if some cams could be a future project. Anone know how much a 2ZZ-GE goes for? In Peso's? :)

[vvtlikick]

Originally posted by t2000gts


if fast and cheap are your requirements for a car, you got the wrong car. GTS 6-speed isn't fast or cheap, and it sucks. you should have checked out some LS1 f-bods.

or maybe...just maybe...you had some certain needs that the GTS 6-speed filled for you that an LS1 couldn't? (you should now be able to use your spatial skills and jump to the conclusion the GTS Auto might fill the needs of some other people who thank god, aren't exactly like you). Whoa..Sorry if I was too harsh on your car up there :o but ....

... I think if most GT-S Auto drivers knew then what they knew now, they wouldn't have chosen the GT-S Auto (they would have chosen a GT-S manual for performance, or a GT Auto for convenience).

There's what...a $4000 dollar difference in price between the GT Auto and the GT-S Auto, and I think that four-wheel discs and the badge and the minor increase in acceleration aren't worth that much.

[QWKsilvr808]

Originally posted by vvtlikick
The GT's horsepower is already declining by the cutoff, so raising the limiter would not increase the peak power (power would keep declining).

If you want high rpm power for a GT, your best bet would be new cams.

You're right on here. :)

If they were to make a set of aggressive cams for your car, only then would you really be able to benefit from the use of a higher rev limit. But for this to happen you'd not only need the new cams, but a new set of valve springs/retainers to handle the job (this is what really determines if you can run a higher redline). Then you can worry about how to get the ECU to shut the fuel off later. :)

[t2000gts]

will valve springs/retainers from the 2ZZ fit the 1ZZ? :) how about cams?

... I think if most GT-S Auto drivers knew then what they knew now, they wouldn't have chosen the GT-S Auto (they would have chosen a GT-S manual for performance, or a GT Auto for convenience).

you mean most GT-S Auto drivers...on this board. i've talked to a few in real life, and they don't give a @#$% either way about anything about the celica except it looks nice and has decent mileage. when i ask why not get a GT auto, it's just "pffft. GT? i'm too good for lower trims." or some **** like that.

and i know that no GT-S Auto driver on this board would rather have gotten a GT Auto for convenience. it's the same thing as far as convenience goes, but IMHO, a lot more fun. i can't imagine living without lift cams to open it up on and sportshift is a neat little gimmick and as far as speed, only reason quarter mile times are similar (but my GTS Auto trapped like 4-5mph higher than similar modded GT auto) is cuz GTS Auto has absolutely no low end. but if my car pulls harder than a GT 5-speed in lift at the top of gears, you know i'd have no trouble pulling away from a GT auto quite easily in highway races (unless he got I/E and H then maybe i'd pull away less easily. and unless he turboed or NOSed or something. then not at all).

[vvtlikick]

Originally posted by t2000gts
you mean most GT-S Auto drivers...on this board. i've talked to a few in real life, and they don't give a @#$% either way about anything about the celica except it looks nice and has decent mileage. when i ask why not get a GT auto, it's just "pffft. GT? i'm too good for lower trims." or some **** like that.

and i know that no GT-S Auto driver on this board would rather have gotten a GT Auto for convenience. it's the same thing as far as convenience goes, but IMHO, a lot more fun. i can't imagine living without lift cams to open it up on and sportshift is a neat little gimmick and as far as speed, only reason quarter mile times are similar (but my GTS Auto trapped like 4-5mph higher than similar modded GT auto) is cuz GTS Auto has absolutely no low end. but if my car pulls harder than a GT 5-speed in lift at the top of gears, you know i'd have no trouble pulling away from a GT auto quite easily in highway races (unless he got I/E and H then maybe i'd pull away less easily. and unless he turboed or NOSed or something. then not at all). I'll just state my priorities when I was choosing a car:<ol><li>Reliable, economic transportation</li><li>Manual Transmission</li><li>Sporty</li><li>Stylish</li></ol>. So if you're right about the priorities of most GT-S Auto drivers, they're similar, with the obvious exception of the desire for a manual transmission.

[t2000gts]

pretty much. but i'd kill for a GTS with a 6-speed SMT like they have in the newer MR2 Spyders :D a real clutchless manual without power loss or performance loss.