Change-up points...?
Discussion
The scariest moment in my TVR has been this;
My wife driving
Me sitting in the passenger seat
Us overtaking a car on a short stretch of road
Accelerating hard
Car approaching fron the other direction
Wife hits the rev limiter in second
Car almost comes to a standstill
And the relevance?
The time to change up is before hitting the rev limiter....
R
My wife driving
Me sitting in the passenger seat
Us overtaking a car on a short stretch of road
Accelerating hard
Car approaching fron the other direction
Wife hits the rev limiter in second
Car almost comes to a standstill
And the relevance?
The time to change up is before hitting the rev limiter....
R
quote:
The scariest moment in my TVR ... The time to change up is before hitting the rev limiter....
How true! When I had my first TVR, an S2, it was some time before I found out it had a rev limiter. One day I was tanking round a sweeping corner on a dual carriageway at fair optimistic speeds in third with everything clenched hope I hadn't overcooked it, mid corner it dawned on my that I'd never revved it *this* hard before and shouldn't I at least glance at the tacho, but I didn't dare disturb anything. Anyway the car decided for me, as it hit the limiter the engine braking transformed a gentle four wheel drift into a massive oversteer and I was left fumbling for opposite lock while trying frantically to find a higher gear. Luckily I found the gear before it got too far out of shape, and as I put my foot down it straightened up without too much drama having used up both lanes and most of the hard shoulder.
I was extremely lucky because at the time I had nothing like the sort of car control skills necessary to catch it if it had broken away.
Cheers,
Peter Humphries (and a green V8S)
On a similar subject, has anyone implemented the change up light on a Griff or Chim (the one at the bottom of the rev gauge)?
I know someone (?Peninsular) did a kit that you could wire in with the option of launch control (which presumably could be used as a primitive traction control).
Ian A.
>> Edited by IPAddis on Wednesday 13th February 14:06
I know someone (?Peninsular) did a kit that you could wire in with the option of launch control (which presumably could be used as a primitive traction control).
Ian A.
>> Edited by IPAddis on Wednesday 13th February 14:06
quote:
I've read a variety of different claims about the limiter on 4L Chimps, ranging from 5850 through to 6500.
My limiter comes in at just over the 5800 rpm mark.
And that's where I change, on a private road of course..
jj
Two rev limiter settings I've some across that seem standard are 6k2 on pre-cat 4.0 V8 and 5k8 on a catted 4.0 V8. I know Mark Adams tends to set them up to about 6k5 - I feel that's worryingly close enough to the 'bang' point of an engine with a stock bottom end (somewhere around 6k7). I wouldn't be too surprised if the 500 cars had different limits though, knowing TVR.
One thing that's been said often but worth repeating - if you have a pre-serpentine front end you really *don't* want to take it past about 5k5 often or for long, as the wear on the dizzy drive increases exponentially with revs. Less of an issue with the later serpentine engines although there's little performance advantage past 5k (and none at all past 5k5).
Cheers,
Peter Humphries (and a green V8S)
quote:
quote:
I've read a variety of different claims about the limiter on 4L Chimps, ranging from 5850 through to 6500.
My limiter comes in at just over the 5800 rpm mark.
And that's where I change, on a private road of course..
jj
Two rev limiter settings I've some across that seem standard are 6k2 on pre-cat 4.0 V8 and 5k8 on a catted 4.0 V8. I know Mark Adams tends to set them up to about 6k5 - I feel that's worryingly close enough to the 'bang' point of an engine with a stock bottom end (somewhere around 6k7). I wouldn't be too surprised if the 500 cars had different limits though, knowing TVR.
One thing that's been said often but worth repeating - if you have a pre-serpentine front end you really *don't* want to take it past about 5k5 often or for long, as the wear on the dizzy drive increases exponentially with revs. Less of an issue with the later serpentine engines although there's little performance advantage past 5k (and none at all past 5k5).
Cheers,
Peter Humphries (and a green V8S)
One thing about the way Mark Adams sets them up though is that it's a soft limit. My Chimaera 4 is set to 6.2k rpm and, on the one or two occasions when I've got there, it doesn't just die suddenly in the wy you describe, Peter, but it (er!) peters out, if you see what I mean.
That said, I agree -- no point with a River V8 in going past 5.5k.
Manek (and his green Chimaera 4)
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