I would like to know if stock valvetrain can handle 9500k rpm, if not wat would you recommend? Thanks

 

some people redline to 9k just fine. I think 9.5k would be pushing it.

 

Most people say 9200RPM.

 

 

you mean regular revs to 9500? or an accidental misshift to 9500? i mis shifted right after i got my car and saw the tach hit 9.5~10k and no damage occured, but i dont think i would try and rev that high regualrly, why not go ahead and invest in some stronger valve springs/retainers if you are gonna try and make power that high?

 

I think that 9200 -9400 is the highest that people push it with an ecu.

 

9100~9500 would be pushing it I would think....with a stock valvetrain..
Just my 2 Yen

 

Maybe yes... but who cares ?
Makes no sense to rev that high with stock cams... You`d need aftermarket cams like Toda B or C to make power up to that range and then for sure you`d need a stronger valvetrain.

So give us some more information why exactly you`ve asked this question..

 

dude, it's cuz high revs r fun -rob

 

wow, you ever gone to www.your-an-idiot.com

 

The reason why I am asking this is because after reading all the post about toda and jun cams and all, the thing I've learned so far is that these cams only makes power up in the high revs. I've currently changed out my ecu and my new redline is at 9k, but it seems like I will have to up the redline a little more if I decided to drop in some aftermarket cams.

A friend of mine said that stock valve train can handle revs up to 9500, but i somewhat doubt his opinion thats why I am asking.

This rev limit in which I am looking at is more then likely to be daily driving...

Thanks for all the replies. I'm just now confused between the Toda A's and B's I've read from several people on this board that there is really not much of a diff... But again I am a newbie in regards to the N/A route so any suggestions coments or tips and pointers would be greatly appreciated.

Thanks
Nam

 

1st Sell your aftermarket ecu.
Get yourself a VAFC or a power fc, smomething like that and get Toda spec A.

If you get other cams, those like Toda A, Jun 2, crower 63402 (power band 100-8500rpm), you`ll need some tuning.

If you like it a bit hotter, get B`s or JUN 2 or 3 and change the valvetrain (must!).

 

The answer to the question about why you would want to shift at lets say 9000RPM when the cams are not working as well can be summed up with this question:

Do you make more power at (a) 7000RPM or (b) 6500RPM?

If you answered (a) then shifting at 9000RPM is going to result in more area under the curve when you go through the gears.

Shifting at the point in the curve where the engine is making its peak power is WRONG, unless the engine can't handle the stress. ANY race engineer will know what I'm talking about.

Regards,

 

Baby NSX,
the guy is talking about revving up to 9500rpm...

 

So is babynsx. If you shift higher, you're in a higher rpm after the shift. That's why some of these guys with tricked out NA cars can run low 13's on 215whp when the SC'd crowd is hitting mid-high 13's on the same amount of power.

 

maybe youre referring to close ratio gear's..

 

bad link... I think it's:

http://www.you-are-an-idiot.com

your = belongs to you

you're = you are




V.

 

To borrow the teachings of Carroll Smith:

So we have to select our shift rpm for the maximum area under the BHP curve. The actual shift point will vary with the nature of the curve, the step between the adjacent gears and the safe limit of the engine operation. TUNE TO WIN pg 144.

 

This is the dyno of my R before the mods were done:
See the curve dipping down RAPIDLY at 7800rpm ??
I doubt it would raise the area under the curve to shift at 9500

 

Try talking to Sgt about it.

 

Maijk190,

Thanks for the plot. I think you have just given me the evidence I needed to prove my point. Unfortunately I'm at work right now so you will have to wait till later for me to finish.

 

If you mean the fuel issue right before vtec, well, yes... If I`d shift at higher runs, the rpm would dip higher above from this power lack..But therefore I need no shifting at 9500rpm... 8600 is enough.... My actual redline is at 9000rpm and I can tell you that revs are climbing very slow above 8400rpm.....espeacially in 4th speed... Note: I am not talking of 1/4 mile racing...
For me, race begins with a shift from 5th to 4th... pulling, shifting...topspeed. And staying too long at 4th while the car is getting slower is deadly.

 

Just wait; you'll see what I mean!

 

ready to learn..

 

It's not so complex. If the curve would be symmetrical at 8000 rpm, the biggest area under the curve would be with 8000 rpm in the middle = powerband between 7000 and 9000 rpm.

But in practice the power drops faster after 8000 rpm than the increase of power before 8000 rpm. So, in practice the biggest area under the curve is not between 7000 and 9000 rpm, but between 6500 and 8500 rpm.... Everyone agree?