# honda has v-tec and nissan has????



## jdm (Sep 14, 2004)

i know honda has v-tech but wat does nissan have :thumbup:


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## viprdude (Jun 27, 2003)

nissan has VVL. search and find out use "sr20ve" and enjoy


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## 97SentraGirl (Apr 30, 2002)

jdm said:


> i know honda has v-tech but wat does nissan have :thumbup:


VVL, VTC and CVTC. I'm too lazy to write out all everything about all the various engines, but here's some quick info about the difference b/w Vtec and CVTC.

From Dec '02 NPM:
Q: Does the CVTC motor in the Spec-V work the same as the VTEC motors in Hondas? If they do, then is it possible to use a VTEC controller in a Spec-V? 

Sarah: No, due to the continuously changing cam profile, CVTC cannot be controlled like VTEC. It is a continuous variable adjustment unlike VTEC which is either on or off. CVTC improves overall engine performance by supplying Constant Valve Timing Control through all operating conditions. The crankshaft position, camshaft position, engine speed, and engine coolant temperature input signals are sent to the ECU. The ECU sends a variable duty cycle to a pulse width modulated solenoid that works like an injector. By adjusting and directing the amount of oil pumped into the CVTC's chambers and allowed to drain back into the engine, the ECU controls the retard or advance of the cam up to 30 crank degrees (vs. 14 degrees on the older VTC motors). The cam is retarded at idle to create a smoother idle and decrease emissions, advanced in the mid range to increase breathing, and retarded at high rpm to increase peak horsepower and fuel efficiency. VTEC is like having a stock cam at low rpm and a race cam at high rpm. At high rpm, the VTEC solenoid opens to allow oil from the oil pump to flow to a piston in the rocker arm. This piston engages a lost motion rocker in an extra intake cam, locking it to the two rockers that control both intake valves. The intake valve on this second cam profile remains open longer which increases breathing. A VTEC controller interprets the MAP sensor signal, throttle position and rpm to activate the VTEC solenoid at the user's specified rpm. It can also add fuel by intercepting the MAP sensor signal and tricking the ECU into thinking the engine is flowing more air. The SR20VE (VVL) has a more similar system to VTEC. VVL is Variable Valve Lift system and changes the lift and the timing of valve opening and closing to exploit the entire powerband, as if working with several different cam profiles during different times in the rpm range. 

Sarah


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## sr20racer (Jun 29, 2002)

Nissan has nitrous.


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## dirrtyjave (Aug 25, 2004)

ahhaahhah! i'd love to get my hands on a sr20ve motor  now if i can only rob a bank... :dumbass: hehehehehehheh :thumbup:


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## jetsam (Feb 7, 2004)

jdm said:


> i know honda has v-tech but wat does nissan have :thumbup:


Nissan has cam profiles optimised for 3000 to 5000 rpm operation.

Variable cam technologies have a problem: less than optimal port runners. With a big runner, VE will suffer at low rpm, reducing the VC system to an anti-cammer device, or with a small runner maximum output is lost, which defeats the purpose of the system.

Why bother? Install a big freeking cam and be done with it. Use the ECU's ability to detect misfire ( per-cycle change in crank angle ) and reduce injector duty cycle on a per-cylinder basis to keep the manifold somewhat dry ( lean out after misfire ), and the engine will eventually light off the fuel in the runner while not dumping too much down the tailpipe.


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## Zen31ZR (Mar 24, 2004)

jetsam said:


> Nissan has cam profiles optimised for 3000 to 5000 rpm operation.
> 
> Variable cam technologies have a problem: less than optimal port runners. With a big runner, VE will suffer at low rpm, reducing the VC system to an anti-cammer device, or with a small runner maximum output is lost, which defeats the purpose of the system.
> 
> Why bother? Install a big freeking cam and be done with it. Use the ECU's ability to detect misfire ( per-cycle change in crank angle ) and reduce injector duty cycle on a per-cylinder basis to keep the manifold somewhat dry ( lean out after misfire ), and the engine will eventually light off the fuel in the runner while not dumping too much down the tailpipe.


With injection points typically being at the lowest end of the runner, there will not be much of any chance of the manifold getting _wet_ as you say. Also a _big freeking cam_ as you so technically put it will not pass emissions requirements, one reason for VTEC and other VVT technologies primary existence. To enhance power when required while not compromising daily driving emissions. At least during the EPAs test cycle, anyway. The latest versions of VTEC don't activate at _all_ during the test cycle, and the moderate low end cam provides excellent emissions control. 
Another thing you fail to understand is that most cars have the cam profiles optimized for the rev range you specify. 3000-5000 rpm is a typical run for a highway pass. Which means that Nissan would be no different than any other nonadjustable cam engine manufacturer. Another thing you seem to miss is that runner sizes are optimized for flow duty all through the cams range and it seems to work quite well. Porsche has flat 6 engines that can make well over 300 Hp naturally aspirated, using it's own version of VVT.


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## jetsam (Feb 7, 2004)

So what you're saying is, you don't think that a catalysis system could produce passable emissions in a fuel injected engine with an injection map designed to lean out misfiring cylinders while 8 stroking?

OK.

But please, say so without attempting to insult me with some "you fail to understand"s and whatnot.


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## Zen31ZR (Mar 24, 2004)

jetsam said:


> So what you're saying is, you don't think that a catalysis system could produce passable emissions in a fuel injected engine with an injection map designed to lean out misfiring cylinders while 8 stroking?
> 
> OK.
> 
> But please, say so without attempting to insult me with some "you fail to understand"s and whatnot.


 I'm not the one who has no clue what I'm babbling about, thanks.


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## Greg200SE-R (Feb 5, 2003)

VTEC's advantage is that they had the R&D early enough to incorporate it into many of Honda's production cars. Nissan could only get VVL out later in the game and in limited cars before they got into financial trouble. 

So now these teens can get VTEC engines anywhere and we are surrounded by them... readily available to them but us Nissan drivers need to pay an arm and a leg to bring in a VE engine to get the same advantages of variable valve lift.

Hondas are ahead of the game more than we think as far as NA tuning. But variable-valve-nonsense won't mean crap next to a Nissan with a snail under the hood lol.


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## sersr20dk (Oct 15, 2003)

Quote:
Originally Posted by jetsam
So what you're saying is, you don't think that a catalysis system could produce passable emissions in a fuel injected engine with an injection map designed to lean out misfiring cylinders while 8 stroking?

do you really think that a huge "cam", which there are actually 2 cams to replace will pass emissions with a cat only and a lean fuel map. on anycar newer than 95 you won't even have a chance. you may get away on an older vehicle, but a big cam will increase emissions greatly.


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## jetsam (Feb 7, 2004)

I wouldn't attempt hot-rodding a car that had to pass an emission level more stringent than tier 1. As it stands, however, my cars don't have to pass emissions testing at all.

By the way, my cars have 4 camshafts and 0 camshafts, respectively.


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## Zen31ZR (Mar 24, 2004)

jetsam said:


> I wouldn't attempt hot-rodding a car that had to pass an emission level more stringent than tier 1. As it stands, however, my cars don't have to pass emissions testing at all.
> 
> By the way, my cars have 4 camshafts and 0 camshafts, respectively.


 What year RX7?


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## Joe_Nizmo (Nov 15, 2004)

*response to the "VTEC"*



jdm said:


> i know honda has v-tech but wat does nissan have :thumbup:


 I thought V-TEC was spelled this way! Ever heard of ECCS?


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## chimmike (Oct 17, 2002)

neither. it's VTEC.


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## Jasper (Apr 2, 2004)

chimmike said:


> neither. it's VTEC.



that is, unless you're talking about that cool semi-clear cordless phone!


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## chimmike (Oct 17, 2002)

then it's V-Tech, because i have one.


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## SR20D_GTI (Nov 4, 2002)

friend owns a crx vti and when we race its pretty close. thats VTEC vs VVL.

my car weighs 200 KG's more then his. 

I think VVL is better just rare. If Nissan had the money they would of produced alot more. 

The VZ-R N1 is quicker then EK9 ctr so thats saying something.


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## jetsam (Feb 7, 2004)

[email protected] said:


> What year RX7?


1985 GSL-SE

streetport, no interior, needs work on _everything_. I love driving it though, feels like F1.


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## Zen31ZR (Mar 24, 2004)

jetsam said:


> 1985 GSL-SE
> 
> streetport, no interior, needs work on _everything_. I love driving it though, feels like F1.


Nice, I had an 84. :cheers: Used to run to the end of the tach all the time. I think the previous owner disconnected the rpm warning buzzer, I never heard it.


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## sentra97gxe (Mar 17, 2004)

[email protected] said:


> Nice, I had an 84. :cheers: Used to run to the end of the tach all the time. I think the previous owner disconnected the rpm warning buzzer, I never heard it.


I have a friend who had an 87 GXL and bought an 89 GTU with what he believed was a dying motor so he was gonna blow the motor and swap the motor from his 87 but he couldn't blow the motor. Said he had it over 10k rpms and still wouldn't blow. Gotta love rotary's.

Mitch


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## jetsam (Feb 7, 2004)

10,000 rpm is awesome... I've heard that doing running that fast for extended periods will eventually mess up the bearings. However, my motor is losing power by redline, so I've never run it past 8000. A 13B 6 port isn't really port-able; it hasn't got as much as it might have at the higher rpms. The buzzer is kinda quirky too; sometimes it comes on at 6500, other times it waits 'til 7500.


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## FrontierTuner (Aug 30, 2004)

jdm said:


> i know honda has v-tech but wat does nissan have :thumbup:


nissan has the sr20det


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## himbo (Sep 20, 2003)

FrontierTuner said:


> nissan has the sr20det


and: 
sr16vvl
sr20vvl
sr20vet
a bunch of rb's (bullet-proof)
vg's (also bullet-proof)
and 
vq's (lots of all motor power potental)
nissan has it all :thumbup:


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## PhaTeLeSS (Oct 22, 2004)

if vvl varies over the entire rev range than that's just like honda's i-vtec. vtec is the on/off cam change. the i is infinitely variable cam timing. the cam sprocket actually pivots in relation to the camshaft on the fly. pretty clever technology actually. the combination makes for a potent little engine like in the new civic si or the rsx (both base and type s). i sell hondas so i get to read all the tech books. no customers ever care but at least it's interesting to me. now is vvl comparable to just the i of i-vtec, or both parts?


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## chimmike (Oct 17, 2002)

it's not VVL. it's SR20VE 

VVL just stands for variable valve lift. And no, it doesn't change continuously, it's like vtec in that it changes cam profiles...but on both the intake and exhaust if I'm not mistaken.

you guys need to stop slapping vvl on the end of SR20, its VE. *cough*himbo*cough*


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## off_da_meter (Sep 2, 2004)

my friend has a GSR and says his VTEC kicks in @ 5000rpm, something like a turbo boost. Is thats how all VTEC response at higher rpm?


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## pete? (Jul 6, 2004)

off_da_meter said:


> my friend has a GSR and says his VTEC kicks in @ 5000rpm, something like a turbo boost. Is thats how all VTEC response at higher rpm?


gsr.. isnt that an eclipes? dsm dosent have "VTEC" they may have something like it but not VTEC, also i thought the gsr was turbo charged 



chimmike said:


> then it's V-Tech, because i have one.


lol you have an answer for everything! lol :thumbup:


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## off_da_meter (Sep 2, 2004)

1.6pete said:


> gsr.. isnt that an eclipes? dsm dosent have "VTEC" they may have something like it but not VTEC, also i thought the gsr was turbo charged


My bad is an Acura w/ GSR motor, I thought we where talking motors here


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## chimmike (Oct 17, 2002)

there is no Eclipse GSR. there's an Acura Integra GSR, has the b18c1 motor if I'm not mistaken.


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## off_da_meter (Sep 2, 2004)

chimmike said:


> there is no Eclipse GSR. there's an Acura Integra GSR, has the b18c1 motor if I'm not mistaken.


finally someone that knows his motors


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## pete? (Jul 6, 2004)

chimmike said:


> there is no Eclipse GSR. there's an Acura Integra GSR, has the b18c1 motor if I'm not mistaken.


sorry i feel like a :dumbass:


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## chimmike (Oct 17, 2002)

off_da_meter said:


> finally someone that knows his motors



don't be fooled, there are quite a few people on this board who'd make me look like a complete idiot in about 5 seconds flat.


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## Zen31ZR (Mar 24, 2004)

off_da_meter said:


> finally someone that knows his motors


Yeah, bumping an old thread, but the correct term for the Eclipse model is "_GSX_". Nice car, I almost bought one, but the uncertainty of the AWD drivetrains reliability anywhere above 300 Hp chased me off. Thats the problem with a tranverse AWD system where the engines power goes through 2 directional changes, one 180 degrees and another of 90 degrees, just to get to the back wheels. Lotta center diff and catastrophic T-case failures on those cars once you get up in the power. That's why I love Nissan, they did it right with the Skyline.


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## jr spec v (Dec 8, 2004)

*headers*

hey ever one im about to buy some headers for my S-ER and i want to know what kind of headers should i get.


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## pete? (Jul 6, 2004)

jr spec v said:


> hey ever one im about to buy some headers for my S-ER and i want to know what kind of headers should i get.


..........did you post in the b15 section? click here then post


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## chimmike (Oct 17, 2002)

jr spec v said:


> hey ever one im about to buy some headers for my S-ER and i want to know what kind of headers should i get.



1) read the new member threads.

2) Don't post something like this in a thread that has NOTHING to do with what you're asking.

3) Please think a little before posting, and a good idea would be to use the search button and/or read through the stickies.

4) Explore the forum. Find where forums are that you think apply to you. Those little titles under the forum tell you what they're for.


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