QR25DE engine

How reliable is this engine and the tranny? Doesn't it have a engine with a "kick" like honda's have VTEC and toyota has VVTL-i? I think it was called CVTC, but i'm not sure?

i dont think it really has a kick, although it does have short and long intake runners, it changes to the short or long depending of its low or high in the revs. kinda smooths out power delivery in a sense.

The CVTC kicks in the lower rpms, that's why you get more torque and a wider power band. Unlike Vtec, which kicks in the higher rpms. Basically, the CVTC performs the same way at 6000rpm as a Vtec would at 8000rpm. But it takes longer to get to 8000rpm than 6000rpm, so the CVTC is already in it's torque peek when it shifts to 2nd gear, while the VTEC is still in 1st. This is why Nissan's cars are excellent for drag racing.

Oh.... nice one.. thankx

if u planning on turboing ur car than this is the best engine to do it. i turboed my sentra and response is really well. the big bottom end allows for minimul turbo lag and the power it puts out on a basic bolt on turbo kit is higher than most. mine did 315 at the wheels when i first turboed it and ita was only 8psi

the cvtc is constantly on and the thing you feel at 5k is the power valves opening not an extra valve or cam lobe

you mean secondary intake runners, nothing too eciting going on but a shorter intake path, hondas system switches to a hi-po cam at a certain point, nissans alters timing and intake lengths

well nissan calles them power valves but they are just another set of runners in the intake

The kick you're referring to are the butterflies actuating in the secondary runners. They only open at a set rpm. 5000 rpm give or take a few hundred. There is a way to control them but I can't recall since it's a pretty new method. Its on thevboard or myspecv .com CvTC is not like Vtec. The two have their differences. But generally speaking they both provide performance for the vehicle.

you can tap the signal that goes to the actuator responsible for opening them, and run it through a window switch for adjustability just like a nitrous system, although it wont do very much in the way of power, it could offer a few HP a little earlier

yeah. the VTC is only a variable advance intake cam. no bigger lobes, just optimized cam timing linked to throttle position. helps get useable power without any real drawbacks. one of the smarter technologies invented in recent times.

someone actually tried the butterfly thing. they removed them completely. lost a tad of power in the early rpms but had a little increase in the higher rpms for the qr. said it wasnt worth it.

im sure you can make some power out of controlling them like vtec in a way, but you would have to have some pretty expensive mods to really see a big gain out of it.

well the point is not to remove them, just to have control over where and when they engage, you would also have to tap the throttle position sensor as well as they only open under full throttle, or open all the way anyways, you can feel the difference when it goes over 5k when your in WOT or just partial throttle

How reliable is this engine and the tranny? Doesn't it have a engine with a "kick" like honda's have VTEC and toyota has VVTL-i? I think it was called CVTC, but i'm not sure?
two words about the QR... sad to say it, but:
Time
Bomb

why do you say time bomb?

countdown to 60,001 miles....lol BOOM!

you mean cuz of oil consumtion...because all you have to do is go to a dealership once when you get the car and they will either tell you its ok or fix it and most of the engines affected by the recal are covered for 100k miles. or if you check your engine oil like everybody who owenes a car should, especialy if you drive them hard. and i have yet to see one catch fire or blowup

its not about oil consumption only. btw, the new qr25de that is in the 07 spec-v has 2 header pre-cats. im not kidding either. that kinda blows.

the reason for prozach to say time bomb is for the following:

1. precat failure in header, breaking up and entering the block
2. butterfly screwed from the intake manifold, through the whole block
3. large dispacement with large stroke = low rpms and more than plenty vibrations. the vibrations are 'eliminates' with the balance shaft in the oil pan, spinning in the oppisote direction of the crank. has known to cause oil problems in auto-x.
4. oil consumption
5. very sensitive knock sensor
6. coolant known for getting into the head gasket

you mean large displacement with LONG stroke, makes for very high piston speeds and they come with super hard rings so oil consumption is inevitable

im going test driving today, im going to flog the piss out of one of those new specs and see what its got, also on the list are both the new evo and sti, along with the s2000 and a bmw 330ci :popcorn:

s2ks are really nice. but they are too expensive for me. the 330cis are nice too. i drove both. id take the s2k if i had another car for a daily though. and the 330ci is a great car too.

make a write up of your review.

and every single on of the problems you mentioned are simple fixes at a dealer and they are free to you. also its been years since ive seen precat problems. dont work an any sentras or sers with knock sensor problems...and like i said the engine is covered on most of them for 100k.

thats if you have a dealer willing to work with you, ive heard shitty stories about 20 million times more than good stories about the dealership, and fixing high piston speeds isnt a quick and easy dealership job, it takes a new crank, crank position sensor, rings pistons rods wrist pins and a lot of time, none of which is covered under your mythical 100k warranty because the dealer thinks its should be set up to burn oil and that its "normal"

well it really isnt dealerships call its a recal from the factory and they dont change the pistons and stuff they just put a new longblock in it. the dealership has no right to tell you they wont fix it if it falls under the recal or the warranty extention

they will blame it on you for modding the car, most likely because you diddnt get an aftermarket header, and locktite the butterfly screws.

also, this is about the engine in general, not just the '06's. there has been so many dealers that screw you over before giving you a brand new engine, like the recall states. if you have a dealer that actually works with you, then you are lucky, as they want you to pay for the new engine.

yeah youve got it right on about how its "supposed" to work, but it never does, they dont want to admit they fucked up by putting a long stroke motor into a sport compact and coupled with really hard/cheap piston rings that equals oil consumption, the only way to fix it right is to basicly rework the whole engine and change it, since that costs a billion dollars they would rather just swap the block, but then they want you to pay for it, i wonder if i blow up mine before my warranty goes if they will give me an 07 spec motor instead of another crappy 05 one?