Rolling Road Results
Discussion
Some details regarding my post-service rolling road session yesterday as Austec and I'm rather chuffed at the state of tune its in right now I have to say.
I've never driven another S, so have no point of reference - I've always found mine pretty niipy, although it had been a little lumpy at low speeds, but I'd always put that down as a TVR quirk.
Paul said he'd smoothed the engine out a little as it was especially bad for town-speeds, he reckoned that he liberated around 7bhp doing this.
The results were 172.4 bhp @ 5580rpm and more importantly 204.8 lb/ft @ 3085rpm. The power is smooth all the way up to 5580 rpm, while the torque tails off after 4000 rpm.
Compared to TVR's quoted 168 bhp and 172 lb/ft I'm 4 bhp and 32 lb/ft up, I'd expected my figures to be considerably lower, as the V8 owners (not Ss) I've spoken to have had been dissapointed.
There has been no tuning done on the engine to my knowledge, and nothing that Paul could see (aspiration standard, manifold blowing slightly and crap exhaust) so there is room for improvement
Paul mention removing the airflow meters, something about airboxes and higher mid-range torque, something I may look into getting done later this year..
My power loss is a lot higher than Podie's though, at 52.9 bhp compared to 32.5 bhp, don't understand why that would be though - will see what I can find out...
Torque
Power
Details
Podie's write-up after his is here.
I've never driven another S, so have no point of reference - I've always found mine pretty niipy, although it had been a little lumpy at low speeds, but I'd always put that down as a TVR quirk.
Paul said he'd smoothed the engine out a little as it was especially bad for town-speeds, he reckoned that he liberated around 7bhp doing this.
The results were 172.4 bhp @ 5580rpm and more importantly 204.8 lb/ft @ 3085rpm. The power is smooth all the way up to 5580 rpm, while the torque tails off after 4000 rpm.
Compared to TVR's quoted 168 bhp and 172 lb/ft I'm 4 bhp and 32 lb/ft up, I'd expected my figures to be considerably lower, as the V8 owners (not Ss) I've spoken to have had been dissapointed.
There has been no tuning done on the engine to my knowledge, and nothing that Paul could see (aspiration standard, manifold blowing slightly and crap exhaust) so there is room for improvement
Paul mention removing the airflow meters, something about airboxes and higher mid-range torque, something I may look into getting done later this year.. My power loss is a lot higher than Podie's though, at 52.9 bhp compared to 32.5 bhp, don't understand why that would be though - will see what I can find out...
Torque
Power
Details
Podie's write-up after his is here.
Tripps said:
My power loss is a lot higher than Podie's though, at 52.9 bhp compared to 32.5 bhp, don't understand why that would be though - will see what I can find out...
From my understanding it could be down to how long the car has been running, as the fluids warm up there is less loss. At one point my loss was in the high 20's...
Given the results of your car it'd be interesting to see how the ECU re-map would change things... somehow I wouldn't expect gains as big as I saw, as yours is obviously running better in the first instance.
Podie said:Length of run could well be it, as mine was a quick post-service RR as the start of the day, while yours was an longer experience.
From my understanding it could be down to how long the car has been running, as the fluids warm up there is less loss. At one point my loss was in the high 20's...
Given the results of your car it'd be interesting to see how the ECU re-map would change things... somehow I wouldn't expect gains as big as I saw, as yours is obviously running better in the first instance.
I'm of the feeling that I won't get huge numeric gains, I'd imagine any tuning will just shift and extend the torque curve really, without investing in better induction, exhausts, ported heads etc.
Now where's that issue of Max Power!!
reparing for rev bob torque show:
The torque curves look very similar but how come Podies is zero at 2000RPM? (or is it my eyesight?!)
Comparing the torque at each 1000 interval shows them as being similar.
Cant read the power one.
All you each have to do is write down the power and torque readings at each 500RPM interval and then compare them.
(And if you write them down in Excel you can get free charts too!).
Tripps, looks like a bloody good result there. Must be a well looked after car.
Comparing the torque at each 1000 interval shows them as being similar.
Cant read the power one.
All you each have to do is write down the power and torque readings at each 500RPM interval and then compare them.
(And if you write them down in Excel you can get free charts too!).
Tripps, looks like a bloody good result there. Must be a well looked after car.
DustyC said:The graphs all have a non-zero origin of both axis', which is why they are difficult to read, making Podie look like he has no grunt at 2000rpm!
The torque curves look very similar but how come Podies is zero at 2000RPM? (or is it my eyesight?!)
Comparing the torque at each 1000 interval shows them as being similar.
Cant read the power one.
All you each have to do is write down the power and torque readings at each 500RPM interval and then compare them.
(And if you write them down in Excel you can get free charts too!).
Tripps, looks like a bloody good result there. Must be a well looked after car.
The Excel idea is a good 'un, but we might even be able to get the source data from Austec for more accurate plotting...
My car has been well-serviced pretty much on schedule, but nothing special by myself or the previous owner from the history I have.
Perhaps it's got a hot cam or ported heads (or other such clever technical stuff that makes my head hurt), but we'll only find that if we delve deeply into the engine... I suppose if could be that my ECU has already been Podieisedtm but I think Paul would have spotted that, and it shouldn't have had the lumpiness he removed.
andyf007 said:Andy,
Tripps, how exactly did Paul smooth out the lumpiness? I'm assuming it wasn't anything to do with the ecu, so it may be something we could all do.
It was something to do with the ECU, but that's all I know. I presume it was something that could be applied simply as I hadn't paid for any tuning.
Podie said:
Keep a copy of your graph plots in the car, next time we catch up, it'll be interesting to compare the figures.
I'll bring mine along sometime too.. From memory I got 151bhp at the wheels; the guy that tested this was quite impressed.. Problem is the power delivery was never very smooth and until I sort out a little niggle I've got at the moment won't improve. Definately feels slower than it used to; will be booking it in for an ECU pampering session in the near future..
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