engine performance
Discussion
hey guys,
I have read a few posts recently from V8 wengined car owners who are saying that their engines aren't producing nearly as much poke as TVR state. Is this true with the speed six engines too or just the V8's?? Only wondering cause i want my future T350 to produce what it is meant to!!
Thanks.
I have read a few posts recently from V8 wengined car owners who are saying that their engines aren't producing nearly as much poke as TVR state. Is this true with the speed six engines too or just the V8's?? Only wondering cause i want my future T350 to produce what it is meant to!!
Thanks.
hey guys,
I have read a few posts recently from V8 wengined car owners who are saying that their engines aren't producing nearly as much poke as TVR state. Is this true with the speed six engines too or just the V8's?? Only wondering cause i want my future T350 to produce what it is meant to!!
Thanks.
A simple rule-of-thumb is to deduct 10% plus 10bhp from manufacturer's figures. With my 5L Chim this was quite accurate. RR bhp was 285 at 5250--manufactures figure was 320bhp less adjustment = 280 approx. Did you see Topgear last Sunday. They tested a T350 and found the suspension a bit impractical for road use.
clint888 said: They tested a T350 and found the suspension a bit impractical for road use.
They tried two setting, the first a track only set up, no body roll or pitch under braking, this tramlined etc. on the public roads and was said to be un-drivable. They then softened the settings to allow for road use, the track handling suffered a bit (1 second slower round their test track when driven by Stig) though on the road was said to be much better. Though not having driven either can't say from personal experience
edited to say: Steve (aka Luca Brazzi) has hosted a video of the TopGear review you can get the link in the T350C on TopGear Thread www.pistonheads.com/gassing/topic.asp?t=25099&f=13&h=0
>> Edited by d_drinks on Monday 30th December 15:13
Ahah - another Thread-that-won't-die (TM)...
There seem to be two camps on PH: The I-don't-give-a-sh#te-cos-its-quite-fast-enough-and-bhp-figures-are-meaningless-on-the-open-road people, and the But-it-says-350-on-the-tin-why-is-it-only-285-its-not-fair-I-demand-an-explanation-and-the-resignation-of-Wheeler folks. I believe both clubs are still accepting applications for membership...
There seem to be two camps on PH: The I-don't-give-a-sh#te-cos-its-quite-fast-enough-and-bhp-figures-are-meaningless-on-the-open-road people, and the But-it-says-350-on-the-tin-why-is-it-only-285-its-not-fair-I-demand-an-explanation-and-the-resignation-of-Wheeler folks. I believe both clubs are still accepting applications for membership...
paul said: Ahah - another Thread-that-won't-die (TM)...
There seem to be two camps on PH: The I-don't-give-a-sh#te-cos-its-quite-fast-enough-and-bhp-figures-are-meaningless-on-the-open-road people, and the But-it-says-350-on-the-tin-why-is-it-only-285-its-not-fair-I-demand-an-explanation-and-the-resignation-of-Wheeler folks. I believe both clubs are still accepting applications for membership...
Who's complaining?? Not me--285 is fine thanks for a car that weighs less than an escort. If I want more I'll tweak it with one of Tim's induction kits. BUT I am intrigued to know how they arrive at these Alice-in-wonderland figures.
Pretty sure they take a blueprinted engine (ie one that has had all it's tolerances/weights adjusted to original spec), then take off all of the ancillaries (alternator etc) & test that.
clint888 said: BUT I am intrigued to know how they arrive at these Alice-in-wonderland figures.
Not exactly an uncommon thing to do by manufacturers - in fact only the Japanese cars seem to give you more than they say on the tin, and that's only because they pretend to stick to a "Gentleman's agreement" of 280PS
I had my Chim 450 (285 bhp) on a rolling road a few months ago, and found that I was actually getting about 240 bhp at the flywheel. If I remember correctly .... about 200 - 210 where the rubber meets the road.
From what I have read on these threads, TVR bhp ratings are all inflated. I wonder why they do that... and TVR is really quiet on the issue. I don't know why some of the car publications, etc haven't challenged them. Maybe it's because everyone does it?
I still love the car however, and knew full well about the bhp descrepancy when I bought it. ... and it does go fast.
:
From what I have read on these threads, TVR bhp ratings are all inflated. I wonder why they do that... and TVR is really quiet on the issue. I don't know why some of the car publications, etc haven't challenged them. Maybe it's because everyone does it?
I still love the car however, and knew full well about the bhp descrepancy when I bought it. ... and it does go fast.
:
I don’t really care about the figures.
It was the 0-60 in 4.2 seconds i was bothered about and guess what people have done this in a Tuscan but not first time.
A article said that it took 7 times to get it right, and doing this it needed a controlled start and careful gear change don’t forget the weather.
A test car driver a bit like the stig tested all the tvrs but not the tomora because he did this before it was on sale.
I say if you want to do this go to a sprint track and practice, you will eventually get there.
It was the 0-60 in 4.2 seconds i was bothered about and guess what people have done this in a Tuscan but not first time.
A article said that it took 7 times to get it right, and doing this it needed a controlled start and careful gear change don’t forget the weather.
A test car driver a bit like the stig tested all the tvrs but not the tomora because he did this before it was on sale.
I say if you want to do this go to a sprint track and practice, you will eventually get there.
This has all been discussed before. However, the best evidence so far is the guys who had their TVR's rolling road tested as a group a year or so back. The Rover V8 cars were well under what TVR had claimed,as was the 4.5 Cerb engine. The 4.2 AJP and the speed six engine were putting out almost exactly what TVR were claiming- around 350bhp.
speed6 said: I don’t really care about the figures.
It was the 0-60 in 4.2 seconds i was bothered about and guess what people have done this in a Tuscan but not first time.
A article said that it took 7 times to get it right, and doing this it needed a controlled start and careful gear change don’t forget the weather.
A test car driver a bit like the stig tested all the tvrs but not the tomora because he did this before it was on sale.
I say if you want to do this go to a sprint track and practice, you will eventually get there.
No problem if you don't mind crashing your clutch at 5250. Then its up to optimum in each gear. Real wear and tear. More important--50 to 70 (overtaking) times on the road.
O well - 
time: Manufacturers quoted power/torque values are for a bare engine on an engine dynomometer. Vehicle Rolling Road dynos will only give value at the wheels and an 'estimate' of losses to give resultant at flywheel. (or am I wrong?) Even then this is for a fully dressed engine so will never be what the manuf. get on the dyno. All manufacturers do it so it's still a valid comparison. Similarly road tests are not what the public can expect to achieve - but can be used to compare cars.
time: Manufacturers quoted power/torque values are for a bare engine on an engine dynomometer. Vehicle Rolling Road dynos will only give value at the wheels and an 'estimate' of losses to give resultant at flywheel. (or am I wrong?) Even then this is for a fully dressed engine so will never be what the manuf. get on the dyno. All manufacturers do it so it's still a valid comparison. Similarly road tests are not what the public can expect to achieve - but can be used to compare cars.Gassing Station | General TVR Stuff & Gossip | Top of Page | What's New | My Stuff