340 vs 320 hp. what changed?

[NicBowman]

Hi. Just interested, in case I need to make corrections when I inspect my cam this autumn.

What was actually changed to drop the published hp from 340 to 320 in the 500s? Cam?

Thx


Nic

[macdeb]

NicBowman said:

Hi. Just interested, in case I need to make corrections when I inspect my cam this autumn.

What was actually changed to drop the published hp from 340 to 320 in the 500s? Cam?

Thx


Nic

Neither reached anywhere near those figures standard. More like 280, sorry.

[NicBowman]

Indeed. But there must have been a physical difference in specification?

[glow worm]

Wasn't there a challenge from Germany about TVRs advertised power ratings ??? IIRC

[mk1fan]

The person tasked with filling in the forms lost track of what story they were telling

[NicBowman]

So just specmanship, no reality at all?

Nic

[Englishman]

NicBowman said:

So just specmanship, no reality at all?

Nic

Pretty much. On the rolling road days I've been to most 500's make 280-300 bhp, one occasionally shows just over 300 but never seen a standard one make 320 let alone 340 bhp.

[2 sMoKiN bArReLs]

NicBowman said:

Indeed. But there must have been a physical difference in specification?

Nope.

Maybe.

I ordered one at the motor show advertised at 340. When the paperwork came through it said 320. I phoned the factory & asked what had changed, the answer came back as nothing.

[DangerousDerek]

Maybe the 340 was on Surrey Rolling Road

[NicBowman]

Thanks. I strongly suspect most Griffith (and Chimera) owners are over 60? Hence focus arguably on smooth driving and comfort would be good! So I am not seeking hp, more just info. Couple of new threads required to discuss age and noise!

Nic

[spitfire4v8]

To confuse things further the very first chim 500s were rated at 290...

[hoofa]

NicBowman said:

Thanks. I strongly suspect most Griffith (and Chimera) owners are over 60? Hence focus arguably on smooth driving and comfort would be good! So I am not seeking hp, more just info. Couple of new threads required to discuss age and noise!

Nic

That’s like saying most harley riders are bald, middle aged , possibly with a goatee and think they look cool I don’t ride a Harley

[NicBowman]

Mm. Yes, would love a Harley but can’t take the image, you forgot to add ‘accountant’ to the list!

I think the demographic relates to when the cars were new, 1993 I couldn’t afford a Griffith, when I was 31. Now at 60 I can…. Young folks mostly never heard of TVR!

[Byker28i]

DangerousDerek said:

Maybe the 340 was on Surrey Rolling Road

I'd trust figures from SRR, they've never been inflated, and we've done several runs there - as you know Derek as you were at the last a

So really surprised by that comment

[DangerousDerek]

Byker28i said:

DangerousDerek said:

Maybe the 340 was on Surrey Rolling Road

I'd trust figures from SRR, they've never been inflated, and we've done several runs there - as you know Derek as you were at the last a

So really surprised by that comment

I have my car tuned by Dale Bladen at Bailey performance. He claims his rollers are accurate and thinks others are a bit generous when it comes to calculating the drive train losses and giving flywheel figures.

I had a NA engine tuned once there and it gave 308bhp, i went to SRR 2 weeks later with nothing changed ind it was 328bhp.
When i had the turbo set up we had it around 470 and when i went to the SRR shootout i got 533.

I do realize you cant really compare apples with pears but it does seem to me if you want the bigger numbers to brag at the bar then go to SRR.
I always say the numbers dont really mean anything. Terminal speeds at the drag strip tells us the real truth.

[NicBowman]

Hi, In my experience the rolling road is best used to optimise your set up, get the best of your car. Absolutes are very hard to be super accurate on, a lot of variables on the day, including air temperature and humidity, tyres and tyre condition, etc, etc. plus the basic variations on the calibration of the road itself. so, everyone is right! But absolute power estimates, are just that…

Nic

[Oldwolf]

I talk to quite a few people who think that the 500 on my Chim 500 is 500hp.
I laughed the first time

[hoofa]

Oldwolf said:

I talk to quite a few people who think that the 500 on my Chim 500 is 500hp.
I laughed the first time

That’s one the reasons I just had to supercharge it , just to be able to yes it is !

[Byker28i]

DangerousDerek said:

Byker28i said:

DangerousDerek said:

Maybe the 340 was on Surrey Rolling Road

I'd trust figures from SRR, they've never been inflated, and we've done several runs there - as you know Derek as you were at the last a

So really surprised by that comment

I have my car tuned by Dale Bladen at Bailey performance. He claims his rollers are accurate and thinks others are a bit generous when it comes to calculating the drive train losses and giving flywheel figures.

I had a NA engine tuned once there and it gave 308bhp, i went to SRR 2 weeks later with nothing changed ind it was 328bhp.
When i had the turbo set up we had it around 470 and when i went to the SRR shootout i got 533.

I do realize you cant really compare apples with pears but it does seem to me if you want the bigger numbers to brag at the bar then go to SRR.
I always say the numbers dont really mean anything. Terminal speeds at the drag strip tells us the real truth.

You forgot to mention you turned up your boost to beat LongBaz 531bhp. Wasn't your first figure somewhere just over 470?

Also that there were cars there with known figures to act as a standard and all pulled almost exactly as expected. Speaking to people noone at the time thought the rollers were over recording.

Thread:
https://www.pistonheads.com/gassing/topic.asp?h=0&...

[spitfire4v8]

Indeed .. the reason I went for the dyno dynamics rollers is because they are known for NOT over-reading, and I'd get figures comparable to SRR as they use the same dyno.