What rpm are you guys happy with?

[JMF894]

Basically the 450 seems extremely willing to rev way past 6000rpm, particularly since I changed the oil as I think it's a little thinner. What rpm is safe with these engines, assuming that you have a healthy one of course. I try to change up around 5500rpm when i'm in attack mode but it is very easy to leave it 500rpm + too late when having fun.

Jimbo

[Wedg1e]

I used to have my rev limiter set at about 6250 but last year's dyno run suggets that there's little point in revving my engine past 6000 as the power is tailing off by then.

[JMF894]

Yeah I don't feel that it's much more to offer after 6k but it just seems so eager to get up there. It's defo more cammy than my old 400 mind. Gives its best around 4000 i reckon.

[matt-man]

My 400 doesnt go past 5k, really tails off after that! The rolling road said the same too...

[Number 7]

The 4.3 lump which I have is known as a bit of a revver, and I have my limiter set at 6100rpm. It's still on a slight upward curve in power at 6000, but for the longevity of the engine it's not worth pushing past 6K (on a standard engine). I would get in on the rollers to see where peak power is and decide from there where you want to limit it.

[wooly350i]

At the mo,any would be just fine.

[mrzigazaga]

Me too..

[Henry Harris]

I have set my red light indicator to 3,500 rpm as my engine pulls so well from low down and I do not need more. I must admint when I first had my car, I used to rev it off the clock, but this proved unecessary unike you like the noise. Also, not being sure of the engine's history, I wanted to get the rest of the car sorted before tackling the engine. Then maybe it will be something different other than the Rover V8 and it will be something that is designed to rev.

[TVRleigh_BBWR]

Standard/slightly modified Rv8 are not designed to above 5500/6000 RPM for any length of time, but if you only reving up and to and then changing then 6000/6500 is fine, the standard lifter will not allow constant high rev's anyway.

I'm still running a standard LR engine with a fast camshaft in the racer (as still rebuilding the racer engine), but I have a soft Rev limit of 6300 and I hit this about 20-30 times in a weekends racing. at Mallory for some reason this was not working and I was doing 7K plus at times (I have a very small pre-load which help it rev higher without pumping up).

So small blasts of high rev's is not going to do any harm IMHO, but if you do have a weak spot or other problems, then you could break it.

[B@man]

At BBWF last year the guys on the dyno said my (MJ) rev limit of 6300 rpm was too high on my 400SE, I've now set the hard cut to 5950 so it limits at just over 6000 and shift lights to :

Green :4500 - Max Torque
Amber :5500 - Sensible Rev limit
Red :5750 - Change fking gear now !

Works pretty well and I've not hit the rev limiter for some time, in fact the shift lights are a lot faster to react than the tacho (looks good too the "traffic lights" are hidden behind the unused central warning light window in the drivers pod)

[wedgeinald]

My 280i (Ford 6 Cylinder lump) has a "red line" on the rev counter at about 6500, the car will happily pull well past the red line in first (had it past 7000rpm on the odd occasion I've been a bit over enthusiastic with it!) Having had the engine (same engine but in the previous car) rolling road tested it suggested that max output was in the 4000 rpm+ range I try to keep my "spiried" driving down below 5000rpm to be on the safe side.

All the above assumes my rev counter is 100% accurate of course.....and the current setup has an exhaust that is more free flowing (and louder...) so the engine may rev more freely and the power may have moved further up the rev range?

I have been amazed at the acceleration of my lowly 280i (according to my GPS logger) it certainly makes my 3.2 Litre X300 Jag seem sluggish by comparison.

[dixiebabes]

Been past 7000 revs on a couple of occasions but thats only when the accelerator gets stuck behind the carpet.

Dix

[JVaughan]

my old 400SE engine used to rev happily to 7,000 rpm, but the new engine doesnt like it above 5,500