Saturday Rolling Road

[george 500]

How did everyone do??

My chim 500 registered 315bhp at 6000rpm and 300lb/ft at 4800rpm. Charlie said that these were some of the strongest figures that he'd seen for a non-seriously modifed 500 (its only got a 404cam and a cold air induction kit) so that was quite pleasing even if it was running lean at the top end. It was interesting to note that there were two definite lunges in the power curve at 2000rpm and 4000rpm though. Out of interest what are peoples losses for power at the wheels? I ended up with 252 at the wheels. Is this about what is expected??

My fathers Kougar ended up with 207bhp which is ok for a Jag XK but had the most amazing torque curve producing 275lb/ft from 2400rpm right through to 3800rpm and 230lb/ft from 1200rpm. Who needs a diesel!!

[trackcar]

My S made 217hp, slightly disappointing as it should have made 230 in that spec. It was fine on the day but started misfiring like a trooper yesterday so it's not a happy bunny.

There were some strong cars there on saturday, none of them really underperforming massively, which was good to see.

Some very strange fuelling curves on some cars though ..

[radzoule]

That would be me then Joo

A whisker under 270 bhp at the flywheel for my 400. I am running quite a conservative advance, and with mapped fuel and ignition I'm hoping I can push that up a little further. Standard ECU trying to fuel my mods did result in quite a lean dip in the fuelling curve mid rpm range - interesting as you noted though that it seemed not to affect the power curve negatively in any way, and it didn't seem to be pinking. I was running it on the 99 ron - I wonder if that helps?

Good fun day out - cheers Charlie. Prize goes to the chap in the standard 400 who made 230 at the flywheel?

[reichejh]

295.5bhp on a completely unmodified 500.

[HarryW]

radzoule said:

That would be me then Joo A whisker under 270 bhp at the flywheel for my 400. I am running quite a conservative advance, and with mapped fuel and ignition I'm hoping I can push that up a little further. Standard ECU trying to fuel my mods did result in quite a lean dip in the fuelling curve mid rpm range - interesting as you noted though that it seemed not to affect the power curve negatively in any way, and it didn't seem to be pinking. I was running it on the 99 ron - I wonder if that helps? ....

Pretty good figures there . Apart from the ignition/ECU is every thing else standard then on yours , as 270 is no small feat for a 400. What was the fly for that .
Good to see the odd 400 give the 500's a run for their money though.

radzoule said:

.............Prize goes to the chap in the standard 400 who made 230 at the flywheel?

Standard with 230 fly is mine seems to make 230/240 consistantly on austecs old rollers whereas most 400's will make anywhere between 175-200 out of the box for comaparson.

[David H]

reichejh said:

295.5bhp on a completely unmodified 500.

[radzoule]

I'm new to this RR malarky so I'm assuming that RR figures should only be compared with like RRs! I do know that its surprised a few people on the road though, although I'm sure a 400 will never match a 500 for torque.

Harry - see my profile - most of the big stuff done, just needs fuel and ignition. My next project is to fit an Omex 150 (I have the electronics, but need crank wheel and some spare time). Is this what you run? If so, are you using a throttle pot or MAP feed?

[HarryW]

radzoule said:

I'm new to this RR malarky so I'm assuming that RR figures should only be compared with like RRs! I do know that its surprised a few people on the road though, although I'm sure a 400 will never match a 500 for torque. Harry - see my profile - most of the big stuff done, just needs fuel and ignition. My next project is to fit an Omex 150 (I have the electronics, but need crank wheel and some spare time). Is this what you run? If so, are you using a throttle pot or MAP feed?

Surprising peeps can be fun, try it in an old V8S , a least in a Chim they might think its a 500 stuck to their bumper, but a V8S .
Agree about the 500 torque, it will always have more.....no substitute for CC's at the end of the day.

re the omex150, yes I have that afaik it is taken from the AFM so it gets the actual engine load, you need to speak to Mark adams as it is slightly modified too. I think taking it straight from the throttle pot is a bit crude afaik.
Your overal spec is not too disimilar to mine except you have a wilder cam so I expect more once you map it .

[vixpy1]

Thanks for coming down guys..

[v8 racing]

george 500 said:

How did everyone do?? My chim 500 registered 315bhp at 6000rpm and 300lb/ft at 4800rpm. Charlie said that these were some of the strongest figures that he'd seen for a non-seriously modifed 500 (its only got a 404cam and a cold air induction kit) so that was quite pleasing even if it was running lean at the top end. It was interesting to note that there were two definite lunges in the power curve at 2000rpm and 4000rpm though. Out of interest what are peoples losses for power at the wheels? I ended up with 252 at the wheels. Is this about what is expected?? My fathers Kougar ended up with 207bhp which is ok for a Jag XK but had the most amazing torque curve producing 275lb/ft from 2400rpm right through to 3800rpm and 230lb/ft from 1200rpm. Who needs a diesel!!

A bit confused with the figures above? you say you had 315 bhp but then you say you ended with 252 at the wheels? or am i just reading this wrong?

[george 500]

When I said that I ended up with 252 at the wheels I mean that that is the non-corrected figure. In other words my flywheel figure was 315 but the figure actually being transmitted to the road (after transmission losses etc) was 252. Just wondering if there is actually any variance in the losses car to car and if my car was typical.


P.S Thank you very much for having us charlie

[v8 racing]

Thats what is confusing me? you have got a 25% loss through the drivetrain where as most rolling roads run an average of 15 austec i think run 10?

[vixpy1]

v8 racing said:

Thats what is confusing me? you have got a 25% loss through the drivetrain where as most rolling roads run an average of 15 austec i think run 10?

Nope, its nearer 20% (take the percentage loss of the flywheel fig, not the wheels). Its always around that on our rollers, always has been for V8 tvr's we've done. And our rollers produce flywheel figs that tie up nicely with engine dyno figs for TVR engines that have been on them.

[HarryW]

radzoule said:

.............Prize goes to the chap in the standard 400 who made 230 at the flywheel?

I've just recalculated this at 20% losses = 287 at the fly

[vixpy1]

HarryW said:

radzoule said: .............Prize goes to the chap in the standard 400 who made 230 at the flywheel? I've just recalculated this at 20% losses = 287 at the fly

Your getting confused Harry, it was 230 at the fly.. can't remember the wheel fig off hand but i think it was around 185-190bhp

[e2djh]

My numbers, for a "bog standard" 450, were 264 bhp at the fly, and 209bhp at the wheels.

Charlie, and Jools (thanks for the informative chat Jools!) felt that this was quite respectable, so it looks like the 20% i am "losing" in the transmission is quite acceptable.

I am happy to be told otherwise, BUT...
from my perspective (i know, i'm putting myself up to be shot ), what is really important to me is not the stats, but the way i feel when i drive this car.

Is there a machine, perhaps a "rolling lips", that can measure "grin factor"

Thanks Charlie for confirming that this is a "sound" 450!

[HarryW]

vixpy1 said:

HarryW said: radzoule said: .............Prize goes to the chap in the standard 400 who made 230 at the flywheel? I've just recalculated this at 20% losses = 287 at the fly Your getting confused Harry, it was 230 at the fly.. can't remember the wheel fig off hand but i think it was around 185-190bhp

thanks for that Charlie got it wrong again , hope the math was right though

[vixpy1]

HarryW said:

vixpy1 said: HarryW said: radzoule said: .............Prize goes to the chap in the standard 400 who made 230 at the flywheel? I've just recalculated this at 20% losses = 287 at the fly Your getting confused Harry, it was 230 at the fly.. can't remember the wheel fig off hand but i think it was around 185-190bhp thanks for that Charlie got it wrong again , hope the math was right though

Math have a gold star

230 at the wheels for a standard car? .. Running on Nitrious i would say

[philr]

Well my slightly modified 500 (224 Cam, air induction pipes and trumpets _ no pre-cats) gave 307.4 bhp which is virtually the same (307.8 bhp) as was shown at Austec when Mark Adams finished his magic on the car. So it seems that the two RR give pretty similar results. It was noted that the SRR torque figures are a bit lower than those seen at Austec.

Thanks for a good day Charlie.
Very useful to see the previous session plotted against the new set up + good to know that the air/fuel mix is spot on now.

Good crowd and plenty of useful info being exchanged.