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Discussion Starter · #1 ·
What makes the GTS engine have more power than the GT? I heard that the GT pushes 140 hp and the GTS pushes 180. Also, is it possible for a GTS to a GT engine swap?
 

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GT-S has vvtl-i (Variable Valve Timing and Lift witrh Intelligence) and GT has VVT-i. They also have other differences (don't think the Lift is the direct cause of to extra 40 horses). Two completely different engines. And, yes, you can swap a GTS motor into a GT
 

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BHam00GT-S said:
GT-S has vvtl-i (Variable Valve Timing and Lift witrh Intelligence) and GT has VVT-i. They also have other differences (don't think the Lift is the direct cause of to extra 40 horses). Two completely different engines. And, yes, you can swap a GTS motor into a GT
But why would you? :thumbdown
 

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JoManGT-S said:
But why would you? :thumbdown
um, for more power? especially if he wants to go N/A. its stupid to build a GT motor for N/A
 

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judging from your quote in bold it says "And, yes, you can swap a GTS motor into a GT"
 

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regardless


the other differences are:

Higher compression ratio, better valve springs, higher redline, and Lift... slight differences to the intake, same everything else... but when all considered thats a lot, the Lift includes a different head, different cam, different ECU, and yes lift does get you all that

i am more familiar with how VTEC works, and the 145hp integra when VTEC is added gains about 30 HP in the GSR, but a whopping 50 in the ITR. It all has to do with the aggressiveness of the 2nd cam profile. This does not mean that there is a 3rd and 4th over head cam, just that there are two sets of lobes on each cam. VTEC is arguably the best setup when considering the Lift part of VVTL-i and i-VTEC, however the toyota engine also has the Vairable valve timing.

The toyota valve timing works differently from VTEC in that toyota acutally advances or retards the intake cam to increase or decrease overlap between when the valves are open for intake and exaust. At higher RPMs you need to have the overlap longer and for this reason: (an example)
You have a cylinder of space and it is filled with exaust gas. Un the upstroke after compustion most of the exaust is pushed out by the piston, but the piston cannot push all of it out on its own because the piston does not ever reduce the combustion chamber to having 0 volume. To remedy this, the intake valve is opened gradually to get intake valve to exaust valve air flow. This flow not only pushes the rest of the exaust gas out, but will suck in more air to fill up the cylinder and thus raising the compression ratio (very very slightly), but more importantly, getting more oxygen and fuel into the combustion chamber making for a more powerful explosion.

Toyota changes the overlap time constantly after i believe 3k rpm and this keeps the engine runnign optimally leading to a smoother powerband and more power. The VTEC on the otehr hand is picking the middle of both rev ranges. The starting lobes are optimized for halfway through the non-VTEC rev range, and then VTEC lobes are optimized for halfway through the VTEC rev range. They adjust the timing simply by having the VTEC lobes start sooner than the non-VTEC lobes.

Now you might say that this shows that the toyota system is better, but then you get to the reliability portion of it. VTEC operates by moving pins inside the contact half of the rockers while Toyota pumps oil through the rocker shafts and into the pivot side of the rocker. This requires extra bolts to be inplace to actually hold the rocker shaft in place, and these bolts are commonly reffered to on this board as the "Lift Bolts". As most of you knwo this wear can lead to breakage and then rotation of the rocker shaft, then the inability to pump oil through it into the rockers and preventing the List portion of VVTL-i to even work. I have yet to see a problem with VTEC. In fact just a week ago i was driving a 92 GSR with 122 k miles on it leaking oil at the VTEC solinoid and it still hit VTEC when i revved it high enough.

If toyota had copied the VTEC system, or found a slightly better way to implement it without possible bolt failure, then the Toyota system would win hands down, but when considering reliability VTEC takes it. Now overall the VVTL-i system i believe is superior to VTEC because of how it also advances ro retards the intake (and soon to be exaust too) camshaft to help increase horse power over all.

* another limitation of the TOyota L as opposted to VTEC is that you are limited as to the amount of lift you can gain by the width of the pin that slides into place to engage the lift. If you had a Lift cam profile that had a higher peak than thw pin had width then you would always be using the big cams lift profile - the width of the pin during normal operatoin which would be bigger than the small cams, and this defeats the purpose of having two cam profiles on one cam shaft


MITSUBISHI OWNERS: Mivac or whatever is basically VTEC, but not as agressive, kicks in at a lower RPM as well.

Here is a page that describes in greater detail the differences between the two systems.

VVTL-i -> http://www.billzilla.org/vvtvtec3.htm

VVT-i and VTEC -> http://www.billzilla.org/vvtvtec.htm
 

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thank you for explaining what is stickied at the top of this section...
 

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Discussion Starter · #11 ·
So you could swap the GTS motor into a GT without spending big bucks on fabrication? Do you think it is just better to mod the GT 40 more horses than to spend on a new engine and cost of fabrication?
 

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well what are your goals with the car?
 

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dont gt's have better outcomes with turbo setups? also isnt the powerband smoother (constant hp incline) because right before lift hits the power drops to give that huge impression?
 

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drewd said:
dont gt's have better outcomes with turbo setups? also isnt the powerband smoother (constant hp incline) because right before lift hits the power drops to give that huge impression?
haha... no. gts will provide better numbers with a turbo, the only hassle is the tuning. but with some of the maps provided by senior members on here its not such a big issue, as for a smoother powerband, i guess you can say that, but then again it can all be tuned.
 

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drewd said:
dont gt's have better outcomes with turbo setups? also isnt the powerband smoother (constant hp incline) because right before lift hits the power drops to give that huge impression?
Where did you hear the power drops to give it a huge impression? There is no way that toyota or any other car company would purposly create something that would drop the power before jumping to a higher power ti give an "impression" what you might be reffering to is a slight flat spot less than a second before it engages, and that only happens if tuned improperly
 

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SlamminS85 said:
Where did you hear the power drops to give it a huge impression? There is no way that toyota or any other car company would purposly create something that would drop the power before jumping to a higher power ti give an "impression" what you might be reffering to is a slight flat spot less than a second before it engages, and that only happens if tuned improperly
actually on a dyno graph, right before lift engages there is a sudden drop of power than a near vertical jump in power, thus making it feel like a sudden burst of power.
 

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Discussion Starter · #17 ·
Carbonized_GT said:
well what are your goals with the car?
I was just curious.. I'm not into big racing or anything just food for thought in terms of saving money on making the celica GT faster.. I take it the GTS into GT swap ins't easy?
BTW.. Thanks for the info guys.. :)
 

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Carbonized_GT said:
actually on a dyno graph, right before lift engages there is a sudden drop of power than a near vertical jump in power, thus making it feel like a sudden burst of power.

wow, you know ill bet you that is when the intake cam is being rotated back to center before lift engages, it makes sense
 

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stuntmasta3o5 said:
I was just curious.. I'm not into big racing or anything just food for thought in terms of saving money on making the celica GT faster.. I take it the GTS into GT swap ins't easy?
BTW.. Thanks for the info guys.. :)

well if you want a cost effective horsepower your best bet is turbo kit.. A gts engine will cost around 2000$ then labor, your still only getting 40 hp with a weak torque rating.
 

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Discussion Starter · #20 ·
Carbonized_GT said:
well if you want a cost effective horsepower your best bet is turbo kit.. A gts engine will cost around 2000$ then labor, your still only getting 40 hp with a weak torque rating.
Ok thanks for the advice man.. :)
 
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