Forums/Z31P/z31-performance-upgrade-forums engine-mechanical-aa/How much do you guys rev?
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JoCkeWe: (2006-12-29 23:51:05)
After reading lots of US Forums I often hear people talk about 6k-6.5krpm shifts as "crazy". My shifting point is about 7200rpm's, and rev limiter is set to 7500rpm's and I think that's pretty moderate. I've never owned a car that couldn't rev 6500rpm.
So, Where is the rev limiter set in your Z? And in your Daily-driver or other cars?
craZed: (2006-12-30 00:26:56)
I run mine up to 7k at the track.
84z31: (2006-12-30 00:33:58)
6k.
theres no more power after that anyway. no turbo yet and it runs out of power after 5500.
Domdogg123: (2006-12-30 00:49:31)
You definetly should have aftermarket cams/heads/intake work to go above 6k at all…My Z just fell on it's face above like 5.5k....
chronic: (2006-12-30 01:17:06)
I only rev to about 6 then I shift when I am having fun.
SATAN: (2006-12-30 02:51:53)
I'm researching and seeing if I can wrap it up to 8.5k rpm's. Built engine
Gritt: (2006-12-30 03:33:53)
rev-limiter? it`s at the end of my right leg…
i`ve bounced it off 8k a few times, but it still don`t make power past 5.5k - 6k
Az4u2c: (2006-12-30 03:36:58)
I totally agree with my NA. Falls flat on it's face at 5600. Any more than that is just noise and vibration, no real power. I ran it to like 6100 once on a dragstrip, and i felt like i'd kicked a puppy or something.
MrwassmanNA2T: (2006-12-30 04:37:17)
Yeah, I Shift @ 6K. after doesn't do much
SATAN: (2006-12-30 04:39:58)
Huge ported heads and intake manifolds help that 6k limit out.
Jason84NA2T: (2006-12-30 05:20:14)
I'll usually hit 6900-7000rpm in first and then shift at 6600-6700 on the 2-3 and 3-4. With the cam timing advanced just a couple degrees there's no point in shifting much higher, and past that I believe the turbine is choking it at higher boost (hence the large falloff in torque if you look at my dyno graph).
On the street I'm usually conservative and rarely take it over 6500rpm.
Your shift points will VERY MUCH depend on your engine/setup specifically, I don't think others can really give you advice unless they're experienced and looking right at your dyno graph or side-by-side ET's. A stock motor falls on its face about the same RPM that my 84 is hitting peak horsepower.
OR-Zman: (2006-12-30 06:20:29)
- shock: I am sure that most of us would like to even be able to be that "conservative". :wink: You crack me up man.
Agreed, shift rpm really depends on the car and the build. There are a lot of "little" things that can make it vary by a couple hundred or so.
hehehe....6500…conservative....still cracking up over that…sorry man. We can just call it small rpm envy. 8)
300zxt: (2006-12-30 09:54:14)
My 86T makes power up till 6.5k - 7k, I just dont think USDM Z31's rev as high from the factory for whatever reason.
Jason84NA2T: (2006-12-30 16:50:49)
AUS got the higher spec euro cams, right?
I'll tell you this… There is no almost differences in the tuning in terms of timing or fuel. Taris Blue's car exhibited the typical bahavior of no power above ~5600RPM as I remember riding in it. The same is true for USDM NA cars. The falloff was fairly sudden and dramatic; you can see it in a lot of dyno graphs. Once we installed the schneider cams (with adjustable gears on +3 degrees) and gutted plenum it was a totally different animal. It feels perfectly flat in power from 5K straight to stock fuel cut of 6450rpm. Just a guess here, but the cams are the one and only notable difference tht I can think of. Same lift but 10 degrees longer on exhaust and 12 degrees longer on intake duration.
300zxt: (2006-12-30 16:57:40)
Yeah the cams are the same as the euro spec, which would definately explain the difference. Interesting none the less…
JoCkeWe: (2006-12-30 17:04:54)
I know, But I was not really looking for advice. Just intresting to see the differences between us. My local friends build their engines(turbos and N/A) to rev as high as possible, and most of the people in US seems to like low rpm power.
mark86t: (2006-12-30 21:38:11)
I must shift at 5900 as my car still sputters at 6000. It USED to rev/pull to 6900 (I was told JWT ecu cuts fuel at 7000) but since I put my 3" cat back on, the car sputters at & above 6000 in every gear at any boost level. It's a beast from 2800 to 5900. I miss the other 1000 rpms. :cry:
280Z Turbo: (2006-12-30 22:24:21)
[quote]Az4u2c wrote:
6k.
theres no more power after that anyway. no turbo yet and it runs out of power after 5500.
I totally agree with my NA. Falls flat on it's face at 5600. Any more than that is just noise and vibration, no real power. I ran it to like 6100 once on a dragstrip, and i felt like i'd kicked a puppy or something.
The L series is the same way. Jason drove my car once and said it was about as bad as any stock VG. I never shift after 5500. I'll probably just keep the rev limiter at the red line of around 6500.
I don't like to run it to high rpm when the drivetrain vibrates a lot and I start to wonder about the cracked rubber in my damper.
In my other car…the Zetec in my Focus makes 130 hp @ 5300, but revs to about 6700 rpm before the cutoff. :? They seemed to have tuned it for torque, not for top end power. Perhaps Nissan did the same thing with the L and VG?
300zxt: (2006-12-31 00:42:38)
That's definately the case for the VG I think, because the RB has shit all torque but revs it's tits off… They're completely opposite engines in that respect so it only makes sense that the VG was built more for torque and not to rev to 10k or whatever.
SATAN: (2006-12-31 02:56:36)
[quote]280Z Turbo wrote: [quote=Az4u2c]
6k.
theres no more power after that anyway. no turbo yet and it runs out of power after 5500.
I totally agree with my NA. Falls flat on it's face at 5600. Any more than that is just noise and vibration, no real power. I ran it to like 6100 once on a dragstrip, and i felt like i'd kicked a puppy or something.
The L series is the same way. Jason drove my car once and said it was about as bad as any stock VG. I never shift after 5500. I'll probably just keep the rev limiter at the red line of around 6500.
I don't like to run it to high rpm when the drivetrain vibrates a lot and I start to wonder about the cracked rubber in my damper.
In my other car…the Zetec in my Focus makes 130 hp @ 5300, but revs to about 6700 rpm before the cutoff. :? They seemed to have tuned it for torque, not for top end power. Perhaps Nissan did the same thing with the L and VG?
Of course thats what the stock USDM z31t was built for. Torque, thats why the whole set up comes with a redline of 6k and a tiny turbo that make full boost by like 3200 rpm or somthing like that.
If they wanted top end power it would have larger turbo and higher redline. But those crazy nissan engineers got this whack idea that Americans are all about 0-60 times or somthing like that.
280Z Turbo: (2006-12-31 03:55:37)
[quote]SATAN wrote: [quote=280Z Turbo][quote=Az4u2c]
6k.
theres no more power after that anyway. no turbo yet and it runs out of power after 5500.
I totally agree with my NA. Falls flat on it's face at 5600. Any more than that is just noise and vibration, no real power. I ran it to like 6100 once on a dragstrip, and i felt like i'd kicked a puppy or something.
The L series is the same way. Jason drove my car once and said it was about as bad as any stock VG. I never shift after 5500. I'll probably just keep the rev limiter at the red line of around 6500.
I don't like to run it to high rpm when the drivetrain vibrates a lot and I start to wonder about the cracked rubber in my damper.
In my other car…the Zetec in my Focus makes 130 hp @ 5300, but revs to about 6700 rpm before the cutoff. :? They seemed to have tuned it for torque, not for top end power. Perhaps Nissan did the same thing with the L and VG?
Of course thats what the stock USDM z31t was built for. Torque, thats why the whole set up comes with a redline of 6k and a tiny turbo that make full boost by like 3200 rpm or somthing like that.
If they wanted top end power it would have larger turbo and higher redline. But those crazy nissan engineers got this whack idea that Americans are all about 0-60 times or somthing like that.
Actually, I think I make 7 psi even sooner than that. :lol:
I could never understand why people said my boost comes in at "x rpm". I always thought boost was based on load.
It almost makes sense to tune the L and VG that way (they're bigger SOHC motors), but I don't know why Ford tuned a 2.0L DOHC 4 cylinder that way.
SATAN: (2006-12-31 03:58:25)
Well it is based on load but generally people are refering to WOT so thats how the x rpm comes in.
Maxmaxima91: (2006-12-31 07:41:15)
I rev my Stock cams and stock head engine to 7 all the time.. and it loves it. peaks around 6700-6800.
Bernardd: (2006-12-31 13:11:24)
`
MrwassmanNA2T: (2006-12-31 20:42:20)
now that i think about it, my car makes power after 6 k. Because It will pull all the way to fuel cut before i can catch a loss of power.
Back when it was NA, you would feel the power go and no when to shift
zed-031: (2007-01-01 00:30:58)
I must be a soft-cock as I haven't had mine above 5k [archived image: frown.png]
300zxt: (2007-01-01 02:08:20)
Yeah you are! haha You have an auto aswell, the gears are so much taller with the 4N71B. As a comparison 1st gear in a manual is good for about 1-2 seconds before you're shifting into 2nd but then 2nd pulls hard as anything after that… Due to the rarity of manual Z's here, my first Z had an automatic and once I finally found a factory manual Z besides the obvious with shifting, my driving technique changed completely… I dont think I could rev my 89 manual turbo as high though, although I haven't really given it a full test yet as it needs a few things done before it can be ran balls out.
VG36ET: (2007-01-01 04:40:59)
Hey bro, You don't need displacement for serious acceleration but you do for serious torque as you may know. It's kinda amazing that an engine engineered in the 80's was used until 2000+ in the Nissan trucks. They should have used larger cams from the factory but that's water under the bridge. The RB for comparison would suck ass in an Xterra without the turbos as that engine has no balls on the bottom end just like the Yota 2jZ but you could still do some serious wheeling with the right gearing to compensate for lack of torque form the engine.
Anyway, My Auto pathfinder will shift @ exactly 6K if you stab the pedal which is fine with me....it's a slow offroad beast compared to most real sportscars. My Z31 is a rolling chassis waiting SAS and everything else/
I've driven friends Z31's that felt dead @ 7K so shifting was generallly done @ 6500ish.
If my VG34ET powered 240SX is pulling hard to 7500 I'm gonna be a happy freaking man…we'll c.
benz-tech: (2007-01-02 02:28:48)
My NA pulls to fuel cut at 6500rpm. Euro cams 3-deg retarded, equal-length headers, gutted plenum but stock heads. The Pathfinder manifold I have sucks about 1k rpm off that but has a fatter torque curve. I need Nistune to get it to 7k +. Right now it really wakes up above 4k but the fun ends too soon. Nothing time and money wont fix…mostly money.
jjewell: (2007-01-02 11:43:14)
some have talked about the heads and intake being the rpm bottleneck. what is safe for the factory bottom end? 7500-8000? what would it take to have a solid 7500rpm shift point?
SATAN: (2007-01-03 00:21:05)
I would say safe for a stock vg30 bottom end is 7500 max sustained. this will give you a piston speed of 4087.5 FPM.
piston speed in feet per minute = stroke in inches x rpm/6
generally the piston on a modern stock(OEM internals) engine should not move faster than around 4000 feet per minute. So ive read.
To have a solid 7500 shift point would require porting, cams and springs. Maybe not REQUIRE cams but…
jjewell: (2007-01-03 01:04:32)
[quote]SATAN wrote:
i'm already in the process of building a set of heads this winter. the only things i haven't gotten yet are the cams and valve springs, i just need to figure out which grind i want to use. as far as springs go i think i'm going to use the scheider outers with new factory nissan inners.
SATAN: (2007-01-03 05:16:01)
[quote]jjewell wrote: [quote=SATAN]
Can you buy the schneider springs without the inners? If not why would you pull the inners and use stock inners? That would lower the pressure
jjewell: (2007-01-03 11:33:26)
[quote]SATAN wrote: [quote=jjewell][quote=SATAN]
i thought the schneider springs were only the outer if it's a set with both i won't split it up. i haven't done a whole lot of research on this yet so i still have some things to figure out.
Elliott: (2007-01-03 16:40:42)
The Schneider springs are both inner and outer. You're probably thinking of the JWT springs, which are outer only.
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JK: (2007-01-04 15:21:51)
Things that affect how far you can spin the engine would be piston speed (ring flutter), and crank flex at high rev's and even the journal size on the crank. But the weakest link on this engine is the valve train. With the correct valve springs (read: nose pressure on cam) this engine should mechanically be able to spin to 7500-8000.
That being said what will prevent you from reaching these numbers is airflow, or in other words, the car is to heavy and the hp is not adequate. On a NA the heads don't flow enough air and you have a severe plenum restriction.
On the turbo, just pump up the boost, if you got it, and deal with the plenum restriction. Peak HP should reach ~7300+ for shifting points above 7500.
For those with deep pockets (none of us here) it is called 'destructive testing'. lower the gearing and spin it till she yields.
Speaking for us cheap bastards, we can just sit back and wait until Satan tells us what breaks first. Just my opinion of course.
Steve88t: (2007-01-04 16:27:29)
Obso did just that a few years ago. Lets say it was over 8k for some time before letting go. I would like to see a stock engine with cams/springs turned up till it wont go any further.