Honda VTEC

[Ceyvme]

Im very interested in the Vtec Discussion. Currently Im a driver of a 92 Teg GS-R turbo. Hitting boost at 3500, and vtec at 5400 makes for a very noticeable change in the drive, and in the sound. When my car was stock though, the Vtec was not very noticeable, and not really discernable. This may be the basis for PD as they are testing stock cars, and theres really not that much of a jump at stock. Not having driven an ITr though, I can't really be sure. Even though I have ITR exhaust and CTR intake cams, Its not nearly the same.

Alot of people do not know that the newer Vtec motors actually have two changeovers in cam lift. Having driven a 2004 RSX Type S for a little while, I found it not even noticeable at stock, while still not that noticeable after a intake and exhaust change out. This is because the newer Vtec motors were built on a basis for economy, using less fuel when the lower RPM cam is engaged, and giving enough power in the upper cams to effectively cruise on the highway.

Honda is also not the only one with the variable valve timing in place. VVT-i with toyota works on the same basis, but theres not as much Valve lift compared to honda's, so its not quite as noticeable. There are many more, but Im not really clear with alot of them, as they all work differently and have different effects on the different motors.


Ive Built and driven alot of honda's in my time, and Ive loved it because of the technology appeal of having the ECU actually switch over your cams as you are driving. I know enough to get me by, but Im also wondering, how fast are the GS-T's in terms of quarter mile and trap speed? The guy talking about a stock GS-T vs a stock ITR confuses me. I never believed a stock GS-t was capable of mid to low 14 second times at the upper 90 mph traps. I have a buddy with a GSX and am well aware of what they can do modded, but hanging with a 185 WHP 2600 lb ITR makes me wonder =P. Not doubting you, or your friends ability to drive, just doesn't sound right.

 

[Ceyvme]

Accords don't have H22's in stock form, they have F22's. If you dropped one in, you HAVE to go turbo with cams.

Correction: H22's did come in accords, but I believe only overseas in the accord SiR. Also, going turbo in an H22 isn't the smartest thing nless its decently built or your keeping the Boost very low (5, 6 psi range) The walls on H22's are very thin, and without sleeves and proper compression, they are very tempermental.

 

[Izanagi]

Im very interested in the Vtec Discussion. Currently Im a driver of a 92 Teg GS-R turbo. Hitting boost at 3500, and vtec at 5400 makes for a very noticeable change in the drive, and in the sound. When my car was stock though, the Vtec was not very noticeable, and not really discernable. This may be the basis for PD as they are testing stock cars, and theres really not that much of a jump at stock. Not having driven an ITr though, I can't really be sure. Even though I have ITR exhaust and CTR intake cams, Its not nearly the same.

Alot of people do not know that the newer Vtec motors actually have two changeovers in cam lift. Having driven a 2004 RSX Type S for a little while, I found it not even noticeable at stock, while still not that noticeable after a intake and exhaust change out. This is because the newer Vtec motors were built on a basis for economy, using less fuel when the lower RPM cam is engaged, and giving enough power in the upper cams to effectively cruise on the highway.

Honda is also not the only one with the variable valve timing in place. VVT-i with toyota works on the same basis, but theres not as much Valve lift compared to honda's, so its not quite as noticeable. There are many more, but Im not really clear with alot of them, as they all work differently and have different effects on the different motors.


Ive Built and driven alot of honda's in my time, and Ive loved it because of the technology appeal of having the ECU actually switch over your cams as you are driving. I know enough to get me by, but Im also wondering, how fast are the GS-T's in terms of quarter mile and trap speed? The guy talking about a stock GS-T vs a stock ITR confuses me. I never believed a stock GS-t was capable of mid to low 14 second times at the upper 90 mph traps. I have a buddy with a GSX and am well aware of what they can do modded, but hanging with a 185 WHP 2600 lb ITR makes me wonder =P. Not doubting you, or your friends ability to drive, just doesn't sound right.

lol that was me...the GS-T guy lol. this was over more than 1/4 mile that we raced...stock GS-T is geared for 176 mph, and having taken the limiter off first thing when i got it, i could pull well over 145, which i belive is the limit of the ITR's stock gearing (4.7xx:1 don't exactly know all the numbers ) The GS-T begins to pull away from the ITR in 4th and 5th, where it has quite a considerable amount of power. If the drivers are good and the conditions are good, a basic race goes: launch, pull ahead evenly, ITR's nose pulls about 2-5 feet past the GS-T's nose, kinda stay like that until the GS-T gets into higher gear, inches up and then pretty much eats the ITR. REMEMBER THIS IS NOT A 1/4 MILE RACE, THIS IS A 3/4 MILE DRAG SO IT SHOWS THE ADVANTAGES AND WEAKNESSES OF EACH CAR!!! i've seen ITR's eat low 13 second GS-T's before so i love the car but i've also seen what a Mitsu can do and it is not to be trifled with...it's so hard to decide which car is better so i love them both!

 

[vtecsolkid]

Woah, 380k, or 38k...?

Sorry how I typed that I typed that . It has Thirty-Eight-Thousand miles.

 

[Ceyvme]

lol that was me...the GS-T guy lol. this was over more than 1/4 mile that we raced...stock GS-T is geared for 176 mph, and having taken the limiter off first thing when i got it, i could pull well over 145, which i belive is the limit of the ITR's stock gearing (4.7xx:1 don't exactly know all the numbers ) The GS-T begins to pull away from the ITR in 4th and 5th, where it has quite a considerable amount of power. If the drivers are good and the conditions are good, a basic race goes: launch, pull ahead evenly, ITR's nose pulls about 2-5 feet past the GS-T's nose, kinda stay like that until the GS-T gets into higher gear, inches up and then pretty much eats the ITR. REMEMBER THIS IS NOT A 1/4 MILE RACE, THIS IS A 3/4 MILE DRAG SO IT SHOWS THE ADVANTAGES AND WEAKNESSES OF EACH CAR!!! i've seen ITR's eat low 13 second GS-T's before so i love the car but i've also seen what a Mitsu can do and it is not to be trifled with...it's so hard to decide which car is better so i love them both!

Ahh I see how it is then, that makes more sense. Highway racing is still my favorite thing to do, as I race quite frequently with a club in my area. No one can say they lost but their car is still faster, because theres not nearly as much chance of driver error coming into play in the race, as its just a straight up put the pedal to the medal and don't miss a gear!

 

[Ceyvme]

Sorry how I typed that I typed that . It has Thirty-
Eight-Thousand miles.

That car must be in excellent condition. My GSR has 74k on the body and 13k on the motor. I can't imagine having that low of miles overall without any kind of swap. Glad people can still appreciate and take car of their cars! I know Im mean to mine but I do my maintennance...nothing like slamming the gears on a quick 145 mph highway pull to get it nice and warmed up for an oil change =P

 

[SC351W]

The new 2005 mustang has infinitely variable cam timing (within a min/max adj range), and "charge motion" control valves. Little flappers in the intake runners that disrupt airflow at lower rpms for more torque. I guess you can't say mustangs are old technology now. seems they've taken a giant leap ahead.

vtec is cool but i prefer cubic inches. didn't "car and driver" do a test with all the best 4-cylinder tuner cars and ran them against a stock Z06 on a road coarse! that was a great article.

 

[prisonermonkeys]

Uh, SC351W, you might wanna trim your siganture to the maximum six lines, because that's waaaaay over.

 

[SC351W]

my bad!!
been awhile since meposty!!

 

[Izanagi]

Ahh I see how it is then, that makes more sense. Highway racing is still my favorite thing to do, as I race quite frequently with a club in my area. No one can say they lost but their car is still faster, because theres not nearly as much chance of driver error coming into play in the race, as its just a straight up put the pedal to the medal and don't miss a gear!

i was talking about starting from a standstill and dragging for a 3/4 mile stretch man...but highway stuff is fun...i remember times when i'd race a dude round Cincinnati with his M3 E36 with Dinan gear on it...speeds in excess of 140 were common if it was in the middle of the nite and no traffic on I-71....

 

[Freddie]

Seeing as how interested many of you are in V-Tec, or rather variable valve timing - a rather common technology actually - this little link surely be of interest to most of you:
Auto-Zine Technical School

Lots of great information, provided on a silver plate in small, digestable portions.

 

[subie power]

i hate v8's and muscle cars as they have huge displasment which is wasted. take a rotary engine for example of an engine with small displasment but huge horsepower if wanted. to me there is no challange with big displacment and i think they suck. id have a 20b tripple rotor over a v8 any day. anyway vetec engines also produce goodish power for displasment, but with a turbo they can produce a lot more. in nz there is an integra which runs 9's standing quater with the help of sum forced induction. but a standard vetec are not that quick, u'd be lucky if u could get into the 14's with an exhuast and filter with (1.8,2.2 letre engines) i have also heard of a honda vetec in nz which is running 18psi through the stock internals with a t/3 t/4 garret turbo which i found amazing. ps there is replacment for displacement and it comes in tor forms turbo and rotary

 

[JNasty4G63]

.....I guess you can't say mustangs are old technology now. seems they've taken a giant leap ahead.

Yea, they're still old-tech, just not as old now. BMW has had infinitely variable cams for quite some time. Its called VANOS, and showed up in 1992. And, hell, Honda has been doing variable timed cams since 1990, so its only taken the Mustang 15 years to get to some form of "current" tech.

.....didn't "car and driver" do a test with all the best 4-cylinder tuner cars and ran them against a stock Z06 on a road coarse! that was a great article.

Do you remember the 2004 One Lap of America?? Only one Z06 ( 4th overall ) out of 5 in the field beat the Vishnu tuned Evo ( 5th overall ), and a Subaru WRX STi ( 6th overall). And that was after the Evo bombed the first event and only scored 60 points, compared to the 285 for that same Z06. So, out of all the Vettes in the event, only one was able to beat a couple of 4-cylinder 4-door sedans. Bummer.

Hilg

 

[xcsti]

I don't really care about volumetric efficiency, though I am impressed by some shining examples such as the buggatti eb 110 or the evo fq330. What I care about is power to weight. I understand that most of the huge muscle car engine is often the worst at this, but not all V8's. An all auminum V8 would provide more power and weigh about the same as a small turbo engine.

 

[SC351W]

rotarys get worse gas mileage than some mild big block V8's. But a rotary is hard pressed to make low end torque without a turbo. You still can't beat displacement, fastest car on drag radials in the country is Rick Head's twin turbo 427 small block chevy. he destroyed paul efantis' mark and ran a 7.66 in the quarter. Paul was also running two power adders N20 and turbo. seems his 130c.i. has a hard time spooling the turbos without the juice, gee i guess that might have something to do with his a/r turbine choice and engine displacement.

so you saying there's no challenge in getting an 813c.i. mountain motor to spin out to 9 grand with the f'in 5" piston snapping the rod in half? rotarys are cool and i'm sure a lot of fun but not too efficient when it comes to making power. OH that there's no challenge in making 500rwhp on 30# injectors and the factory ECU (unprogrammed). try looking up the BSFC on 30# and tell me why my motor doesn't blow under 12psi Unfornately (gas prices) it is my daily driver also. Do you know where ford EEC-IV programming came from?

vtec is not infinitely variable it is a preset change in timing and lift (on/off switch). I believe the mustang is the first to have continously variable on a SOHC. whil bmw has been doing this on a DOHC set up.

The article i was talking about was not the OTC, but an actual write-up and full test of all five cars. But since you added that the corvette finished in front of all of them in the OTC what category was the corvette running in and were the EVO and others in that same class? Have you ever driven a Z06 on track? By bombed did you mean the EVO had problems? car trouble or bad driver?


I agree true enthusiasts, like myself appreciate a race vehicle that has an astonishing power to weight ratio. the only downfall is that aluminum blocks will not hold power without sleeving, which is big $$ the more cylinder you have.

Sorry but i'm just in love with the various sounds of a V8, some reason it seems to hit the sweet spot, V10 weird, V12 weirdx2, v6 (puke), 4-bangers (umm no turbo?).

I could keep going on, i love talking about this stuff. I'd love to get down to the core of horsepower which is simply cylinder pressure (by whatever means) and chamber designs.

honest question, are there other vehicles that use runner controls to direct airflow?

 

[subie power]

rotarys arnt effiecient at making power! i nearly fainted from ur stupidity. a two letre rotary can produce over 1400bhp. i no of a rotay mx6 in aus that has run a 6's quater. rotary is a far better design than a pistion engine as piston engines go up stop down stop up stop etc and a rotary never has this problem it will just spin and spin. i have a pistion car but i can admit that rotarys are a far better desiged engine than any piston design. id like to see some one get 700bhp from a 2.6L n/a engine like the rotary did and it also was track spec so it had to last a cosiderable time. even with an alloy v8 the weight of it is far greater than a rotary engine.

 

[xcsti]

Rotaries are incredible efficient but you pay for it in oil.

 

[SC351W]

sorry should have clarified, efficient regarding fuel consumption.


regarding stupidity, if rotaries are so efficient it must stupify you as to why only one manufacturer messes with them what could the other guys be worried about (i.e. fuel consumption, emissions, long term service, heavy duty service) that's efficiency on a broad scale not limited to one category of hp/L by which it does not dominate.

so lets take a 2.0L rotary 122c.i. motor and it makes 1200 hp or 9.836 hp per cubic inch.
now lets take a top fuel motor which is 8.2 liters 500c.i. and makes 8000hp (est) or 16 hp per cubic inch.
now current formula 1 uses a 3.0L V10, 183 c.i. and produces roughly 800hp (est) which is 4.37 hp per cubic inch.
pre-turbo ban formula one used 1.3L (i think 4 bangers) 80c.i. motors and produced about 1600hp (rumors abounded of 2K hp) which is 20 hp per cubic inch.

interesting... the rest of the world is crazy to not love rotarys!!

 

[xcsti]

that's efficiency on a broad scale not limited to one category of hp/L by which it does not dominate.

??

so lets take a 2.0L rotary 122c.i. motor and it makes 1200 hp or 9.836 hp per cubic inch.
now lets take a top fuel motor which is 8.2 liters 500c.i. and makes 8000hp (est) or 16 hp per cubic inch.
now current formula 1 uses a 3.0L V10, 183 c.i. and produces roughly 800hp (est) which is 4.37 hp per cubic inch.
pre-turbo ban formula one used 1.3L (i think 4 bangers) 80c.i. motors and produced about 1600hp (rumors abounded of 2K hp) which is 20 hp per cubic inch.

interesting... the rest of the world is crazy to not love rotarys!!

Let me ask you this, how much money and developement time is sunk into that rotary? Now apply that question To all the other engines you listed. How much does an F1 engine cost? The rotary is much cheaper to pull power out of. A top fuel runs mostly off of nitrous and has a ginormous supercharger. I can't remember the exact mixture of nitrous to ethanol but I do know it is mainly nitrous. They also have to rebuild the engine after every run (quite a feat). I'm not dissing top fuel cars, though I want to try and fit in a joke about the fact that they run off mechanical fuel injection (isn't that like 50 years old?).

 

[k20a1emcivic]

I'm a bit of a Honda fan, but I don't exactly rice my rides out like you guys probably do.


^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Ok whoever wrote that is wrong, I'm by far one of the best guys in Miami to build Hondas. I don't rice them out, I'd rather JDM the whole thing. I don't put those ga* lights on the cars like most of u idiots do. And it's funny how you all have VTEC Hondas. That's bullshi*. If you do, I have a Pagani Zonda C12S and 2 Ferrari Enzos. As*clown.<-- for guy w the NSX, DEL SOL AND PRELUDE Anyway and FYI I've seen 2 turbos on an I4 before so before u talk, listen, then learn. I know it'd be better to put a T3/T4 hybrid. But what he wanted was a huge turbo, and thats what the small turbo would be there for, to spin the larger one till it can boost on it's own, hence the name "SEQUENTIAL TURBO"= In a sequence. Next time keep quiet cuz I obviously know more than you do. 👎

 

[k20a1emcivic]

Correction: H22's did come in accords, but I believe only overseas in the accord SiR. Also, going turbo in an H22 isn't the smartest thing nless its decently built or your keeping the Boost very low (5, 6 psi range) The walls on H22's are very thin, and without sleeves and proper compression, they are very tempermental.

I know they were in Accords but where? JAPAN BTW they were in the Accord Euro-R. I meant over here, they're non-existent in Accords.

 

[xcsti]

Uhh, could you please name who you are reffering to or quote it and not just say "whoever wrote that". It would kind of cut down on the confusion. I thought you were dissing me.

Edit: this is reffering to k20a1emcivic.

 

[subie power]

in regard to efficency for a rotary i was regarding the way a rotary works. its not fuel effiecent nor emmision friendly but how a rotary goes round and round and does not stop is a far better design to a pistion engine. as already stated those top fuel dragsters are used for like one run and are unbeleivibly stressed so i would not consider that to be counted as u could push over 2000bhp for a 2L rotary for a quater mile run but that is pointless. the rotary i was talking about produces 12-1400bhp (depending on boost) and it is used for a season.

 

[SC351W]

??



Let me ask you this, how much money and developement time is sunk into that rotary? Now apply that question To all the other engines you listed. How much does an F1 engine cost? The rotary is much cheaper to pull power out of. A top fuel runs mostly off of nitrous and has a ginormous supercharger. I can't remember the exact mixture of nitrous to ethanol but I do know it is mainly nitrous. They also have to rebuild the engine after every run (quite a feat). I'm not dissing top fuel cars, though I want to try and fit in a joke about the fact that they run off mechanical fuel injection (isn't that like 50 years old?).

so your saying mazda didn't sink a lot of money in the rotary, in the reknown car? cost is only one aspect of a wider look at efficiency, they're are trade-offs for it. You cant run nitromethane in a rotary the casing of a rotary will only handle so much pressure before it pops like a baloon. You may be able to run methonal in a rotary but it would be counterproductive too slow of a burn rate, by which you would need to compensate with oodles of cfm like 190lb/min. formula one, IRL and CART run methanol.

here's a joke about mechanical fuel injection, show me an electronic injector that #1 will pump a couple gallons of nitromethane in 3 secs, will not malfunction under the NVH and heat of a top fuel motor. Such old technology, almost as old as the wheel!

So if rotarys are the white unicorn of efficiency, it's strange you don't see them in the top levels of racing. why didn't formula one progress towards rotaries, their rules used to be wide open, and they are such sticklers for weight, it would have been a match made in heaven. maybe that's cause their are trade-offs that don't pay off in the end. cost is a weak argument.

 

[SC351W]

in regard to efficency for a rotary i was regarding the way a rotary works. its not fuel effiecent nor emmision friendly but how a rotary goes round and round and does not stop is a far better design to a pistion engine. as already stated those top fuel dragsters are used for like one run and are unbeleivibly stressed so i would not consider that to be counted as u could push over 2000bhp for a 2L rotary for a quater mile run but that is pointless. the rotary i was talking about produces 12-1400bhp (depending on boost) and it is used for a season.

I'd love to see that rotary last a full 10 race season without breaking. HAHA!!! That's a very tall claim.

how do you declare a design efficient? what impirical data can you give that says a rotary is more efficient? I mean are we weighing opinions? cause in my opinion rotaries sound like @ss and every time some bum brings his N/A 20b RX3 to the track and winds it out to 10 grand with what sounds like an open uncollected header, that makes everyones ears bleed just to run 12's. is pretty inefficient to me. At that point i don't care if it has less reciprocating mass, or that the internals are subjected to less stress, cause the amount of noise that guys car made was greater than he'll ever run fast. but hey that was a subjective opinion.

 

[ND4SPD]

Then again, comparing the rotary to a piston engine car isn't too fair, the piston engine has over a century of engineering, while a rotary has a little over, or under 50 I believe. So if a rotary had the same amount of engineering time as a piston engine, the rotary would be supreme.

 

[k20a1emcivic]

Soryy x, I was talking to BadBatsuMaru. Since he seems to know SO MUCH about Honda haha he's funny. Magazines don't compare to hands-on knowledge SON. lol haha 👎 👎

 

[xcsti]

so your saying mazda didn't sink a lot of money in the rotary, in the reknown car?

I was talking about the drag rotary mentioned earlier, but you do have a good point. Then again you proved my point as that rotary won, proving it can last a 24Hr beating, and be practical.

So if rotarys are the white unicorn of efficiency, it's strange you don't see them in the top levels of racing. why didn't formula one progress towards rotaries, their rules used to be wide open, and they are such sticklers for weight, it would have been a match made in heaven. maybe that's cause their are trade-offs that don't pay off in the end. cost is a weak argument.

As in Le mans most series banned them. The lack of businesses building rotaries also contribute to the lack of rotaries in racing. Why would a F1 engine builder spend a few hundred more million dollars developing the ability to create a rotary when they can just slap on five valves per cylinder and a massive bore on a power system they are familiar with producing.

 

[S13DRIFTSPEC]

With FIA Rotaries are to be equivalent to a four-stroke piston engine of twice the displacement. Since its power stroke occurs twice as many times in a revolution or something like that. So basically the 26B is considered a 5.2L engine. 700hp isn't too hard on some N/A 5.0L V8s.

The Rotary's true strength isn't with the power it makes. Due to its compact size and light weight it makes the car have a lower center of gravity since it can sit lower and further back.

 

[JNasty4G63]

I believe the mustang is the first to have continously variable on a SOHC. whil bmw has been doing this on a DOHC set up.

Big deal. So its taken them 15 years to get half of the work done. I'm all about advancement, but I would surely not call the Mustang "high tech" now. I mean, Sentras, some Hyundais, and even some Kias, just to name a few, have CVT in their cars now. Its nice to have, for sure, but its by no means "high tech" in a car today.

But since you added that the corvette finished in front of all of them in the OTC what category was the corvette running in and were the EVO and others in that same class?......... By bombed did you mean the EVO had problems? car trouble or bad driver?

Not sure what you mean by "OTC", but I'm referring to the Car and Driver race called the "One Lap of America" run in May every year. And, no, they were in different classes. The Evo and STi that finished 4th and 5th, respectively, were in the "Mid-priced Sedan" category. While, all of the cars above them in 1st through 4th were in the "SSGT1 Big Bore" category. I'm not saying the Z06 is a bad car. Just showing you that some of the 4-cyl cars can be very fast. There were five 4-cyl cars in the top 20 final standings.

And when I referred to the Evo bombing the first event, it was set-up error. They were using a clutch style front LSD, and had it setup too strong for the first event, which was a wet-skidpad, and understeered terribly. After that mishap, they were pretty much top-5 every subsequent event.

Have you ever driven a Z06 on track?

Nope, no desire to. I mean, they are fine machines, but I'm content with my Talon. Its a very quick car at the strip, as you can see in my sig, but I rarely take it there. Its just a nicely set-up street car that I auto-x frequently. And, it holds its own. I've tracked it a few times here at M.A.M., and its a very competant machine. If it weighed just a bit less, it would be great. But, I'll take a little weight to have the AWD. So, again. I have nothing against the Z06, or any V8 car for that matter. But, I wouldn't call any American V8 "high tech" by todays standards. Maybe the new Hemis, but thats a stretch. But, also, those big engines don't really need to be high tech to get the job done.

Thats the difference. For a naturally aspirated car, the "no replacement for displacement" addage holds true. But, if you don't care about staying NA, a big turbo can be a great equalizer. Look at all the new Lingenfelter and Hennesey cars. They're wicked quick because they have twin turbos spooling up boost for them. I'm all about power, no matter which way its made. If you have a big 528 Hemi, thats cool. Or, someone with an 800hp singel turbo MKIV Supra, thats cool as well. I just like speed.

....honest question, are there other vehicles that use runner controls to direct airflow?

Again, Honda has done this for years. They've used a dual runner system on the intake manifold of many of their engines. In normal conditions, only one set of runners is used. But, when the cams kick over, and more air is needed, the second set opens and flows. Again, its a nice technology for the Stang to have, but its not new.

Hilg