Hey guys,

The V12 love to rev, but where is the proper redline, at which the engine will limit the rpm to?

As I'm doing the TH400, I want to adjust the modulator to allow full throttle reving in 1st and 2nd to the redline and then a shift. Or basically until the redline begins... I habe something like 6500 rpm in the back of my head, is that right?

Cheers

Damien

 

that's right according to the Tacho Daim but l have found they will happily rev past that point, at least my old series 1 did.

 

Hmm... Does that matter if Marelli or not? I mean, I know these engines will rev their guts out if wanted, but I didn'to really want to do that. If the red line starts at 6500, then that is where I make the full throttle switch at. Waste of time having a tranny on a V12 that will omchange gear at 5500 rpm on an engine willing to rev higher... I doubt i'l use it, but if it says so in the dash, then I'll do so...

 

I seem to remember reading somewhere that the HE engine will not make any more power above 6000 RPM and hardly any more above 5500. I reckon a change up at about 5750/5850 is ideal, so the next gear particularly top, is not too big a leap for the revs.
Greg

 

Hmm... I'll have to see when max power is made. And decided around that...

 

Ideal shift point is where the shift puts the engine near its torque peak when shifted.

The HE engine has a flatter torque curve and peak tq is lower rpm than pre HE. IIRC peak power for HE is around 5800rpm. I have reved mine to 6500 and it does make a difference in 0 to 100 times.

 

i do it a little different , rev past the torque peak so when it shifts its right in the torq. peak , so starts pullin up to HP peak!

the 6.0L cars i have driven feel like its wasting time after peak torq. around 4500 RPM, altho will run out around 5500 or more but seems to be screaming not pulling.

i,m a accelleration guy , not really a top speed guy, i like things to be done by 120 /130mph.

of course on autobahn things may be different..

now dont forget we are talking yestedays performance cars , todays hi perfromance cars will leave us in the dust, on both acell, and top speeds.

 

6500 rpm sounds right for the actual redline. I usually shift my 1988 XJS at 5500 and by the time the slushbox transmission actually shifts it is closer to 6000 rpm.

 

The engine will run to like 7800 before the valves start bouncing in the springs.

As the tach shows, its 6500, I think the pre-he and HE variants make peak power around 5500, but obviously your concern is shift points, which is entirely dependent on the transmission. You are trying to find where the difference in torque between the two gears would be minimal.

 

Problem is, I don't know if the Mareli ignition system puts an RPM limit in earlier. Lacking a running engine at the moment...