Reved off the clock

[Graham]

Hi people,
The other night i had a blip with an older (2002ish) HSV commondore (Holden Clitoris) and as i was showing him a clean set of heels, i decided to see what it'd rev to in 2nd, and it went of the rev counter--i thought this shouldn't be possible, but it went to where the 8k line should be before i decided to change--it seemed to want to go further but my ears were bleeding and i was cringing as i have never take it this far before. As anyone got any idea's--obliterated the commondore though over 800m i was over 100m ahead from him being just behind me.

[Sonic]

Ive always wondered this also - i rev'd mine up to "see how far it would go", got to 8k and bottled it - which is probably sensible!

Sounded awesome though

[Rusty]

What, you mean the rev limiter in an S2? That's 7400rpm. Hit that on a regular basis, not is 5th tho TBH, on a k24 there's no point taking it above 7k.

[Sonic]

Im thinking we dont have rev-limiters then?

[Rusty]

Sounds like something is a little funny there... no brap-brap-brap change gear

[Acidburn]

I've had mine way off the limiter in both first and second, if you did it just right it would just sit there bouncing around like some of the higher powered s2's on you tube end up with, I tended to change when the car got to the right speed on the speedo as it was more acurate.

Plus as people have seen the abuse my clutch put up with its not the best of ideas at times but damn good fun and if you catch it just right you get a nice flame out the back

[Ross]

I really wouldn't get into the habit of taking the revs off the clock!! All sorts of issues there - I looked into getting a reliable 8,000rpm with my 'project 400' and came to the conclusion it really wasn't advisable with the hydraulic tappets.

With stock rods, I don't think you'll over-rev it too many times before you realise why the rev limiter is usually there! A set of forged balanced rods are required if you want to do that on a regular basis.

Stock limiter is 7,200rpm, mine was raised to 7,400rpm, if there was no limiter I'd keep a keen eye on shifting by 7,500rpm.

[GazzaG60]

ross is right.

if you did that on a G60 supercharger a few times then a cloud of magnesium alloy was heading your way.

if you wanna take it close fit a soft limiter.

guys we are sounding a bit like the honda vtec limiter bouncers here.

[Fat Audi 80]

But is there a physical cut is the question?

I don't think I have ever been much over 7000rpm to find out. It certainly is not much fun in a standard S2 as they don't breathe well enough at the top end. With a decat and miltek it feels stronger at the top end and revving over 7k is more realistic, but I still am not much of a fan....

[mcandmar]

Valve float is your big worry at high revs, when my 7A had a broken valve spring (the small inner one) it used to get valve float at exactly 6300rpms. It eventually bent a valve and i had to pull the head off and replace it. Since then it gets regular exercise to the limiter ~7300rpms. I wouldn't want to rev any higher without uprated springs, or light weight lifters.

[Acidburn]

Valve float is your big worry at high revs, when my 7A had a broken valve spring (the small inner one) it used to get valve float at exactly 6300rpms. It eventually bent a valve and i had to pull the head off and replace it. Since then it gets regular exercise to the limiter ~7300rpms. I wouldn't want to rev any higher without uprated springs, or light weight lifters.

Just wondering what noticable problems you got for you to find this out, was it noise or other problems just so I know what to look out for/hear for.

[S2central.net]

Sounds like Graham's has had the rev limit in the ECU significantly dabbled with !!!

8000rpm is OK if you are on the right cams and solid lifters, but I guess that headwork may be required for useful VE at those rpm levels. Dunno if flow is limited by cams or the head itself at that point...

[GazzaG60]

id say yes on the headwork. you can use the later mlightweight lifters and uprated springs but they have trade-off too.

crespo do a nice set of cheapish solid lifters but its the cams that cost. also they wont be that streetable id expect as most go to solids for top end power.

also like others have said unless you are runninga turbo that can hold onto the torque line up there whsts the point anyway.

if you want 8k rpm then there are a lot of other bits you must do first to make it worthwhile anyway. or buy a honda, fit a turbo kit and see off all but thevery best high hp s2's

[Dingo]

My limiter definitely works cos last time I had it on a rolling road I was standing right next to it, thinking this sounds great, when it hit the limiter (7200) there was a massive bang out the exhaust and I s..t myself

[mcandmar]

It would rev fine to 6300rpms then hold back, my natural reaction was to lift off or change up as it didnt feel right. If you pushed on it would miss fire and make a very uncomfortable sound.

For ages i thought it was the rev limiter cutting in due to some electrical glitch, i only found it by accident as i broke an exhaust stud converting to the early 5-1 manifold and had to pull the head off. Since the head was off i went all out with a port and polish and replacing valve seals. Only then i found three broken valve springs and one bent valve. I was shocked when i found them, never would have suspected. The difference was night and day after the rebuild, it loves to rev and will happy run to the limiter in every gear. ....including 5th