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Old Mar 28, 2003 | 08:05 AM
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From: Sunny Ilson
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Just thought I`d share this with you...

I`ve had my Series McRAE for 8 months now before my Scooby I had a Fiesta RS Turbo as you can imagine i was looking forward to driving the Scooby!
First impressions were nice car, good build, great handling decent power but not what I expected, I felt my Fiesta was as quick!?!
After speaking to the previous owner and at a RR day I found the boost was quite low down the rev range, upon closer inspection at the last RR day the car was only pulling 160BHP @ 4000 revs 9psi!!!
Oh and 298BHP @ 6000 revs 15psi!??!?!?!?!?
I`ve recently had it sorted and WOW what a difference, full boost throughout the rev range, its like a different car the smile factor has trebled!
150bhp car for 8 months now i`ve got a 250bhp car for little extra money
My faith has been restored back in Subaru`s because before I thought they were quick but not THAT quick.
BRING ON THE WEEKEND
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Old Mar 28, 2003 | 08:19 AM
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What was wrong with it??? You poor sod....running with just 160bhp. At least it gets you used to the handling first before you unleash all them horses......

Have(safe!)fun...
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Old Mar 28, 2003 | 09:04 AM
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You could always borrow or even buy mine doc then you will feel fully restored (21.5 psi)
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Old Mar 28, 2003 | 09:09 AM
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LOL @ Doc. How is it going? If you think thats bad I was running around in my Fiesta @ 2/3psi for the first 4 months!! I hate to think what tremndous power that was giving out Then I went to 14psi I didn't know you got a Mcrae you lucky sod that is what I was planning! I got rid of my Fezzie last year and got a Clio Williams [Carl.Frst]
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Old Mar 28, 2003 | 09:12 AM
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What was up with it ? ... I'm sure mine is underpowered too
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Old Mar 28, 2003 | 10:13 AM
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I think mine is under powered too. I'm only 21 and have had my MY99 UK Turbo for a year (induction kit, decat blitz system), so i should be thinking its the fastest thing ever...but i dont!!! It is pretty quick but i dont think i am seeing its full potential!!

What was wrong with yours Doc???!

Dunc.
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Old Mar 28, 2003 | 10:19 AM
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From: Sunny Ilson
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LO All,
Carlos, it had to be done best decision I ever made.
R.B, I`ll stick with mine it costs enough as it is

As for the problem basically somewhere down the line a KnN induction kit had been fitted and the boost solenoid had been disconnected, this meant that I had only 9-10psi boost low down the rev range and full boost at very high revs.
I had all the pipework put back last weekend, standard boost solenoid fitted and ECU reset but still retained the KnN, giving full boost throughout the rev range which makes a HELL of a difference.
Looking at the RR graph the BHP / Torque curve was flat up to about 5000 revs then things started happening at 6000 298BHP?!?!? from a UK car de-cat, induction :wow:
Need to get it RR`d again now to check the curve is OK.

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Old Mar 28, 2003 | 10:21 AM
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From: Sunny Ilson
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Carl,
3000 + posts!!! looks like you have been planning it for a while!! Happy hunting mate.
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Old Mar 28, 2003 | 01:32 PM
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Oh and 298BHP @ 6000 revs 15psi!??!?!?!?!?
This is what really confused me about boost to bhp ratio and RRs.

1.0 bar is about 14.7 psi

Mine runs 1.2 bar 17.6 psi on a bigger VF29 turbo.

Yet I only got a figure of 260bhp and everythign was spot on.

The RRm guy did say on my gauges it hit and held just over 1.0bar on the RR but even so it would mean its close to 15 psi so whose right ??????

I am now very dubious about any RR figures as it looks like from one road to another it could be as much as 50bhp difference on the same car .

This would be a cracking article for a performance car magazine, they compare everthing else so why not rolling roads if poeple set so much store by them ????



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Old Mar 28, 2003 | 01:52 PM
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From: Sunny Ilson
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chrisp,
Just to put another spanner in the works, The RR controller said that the Torque was very low due to the PSi being low this meant the BHP was higher due to Torque being lower? If the boost was upped then the Torque would up and the BHP would drop to a "normal" level.
Next time I`m expecting somthing like 250bhp / 230 Torque ish 15 psi max
Last time 298bhp / 195 Torque @ 16 psi (@ 6000 revs)

One thing about RR`s is they do differ around the country, the figures quoted above are all from John Nobles in Chesterfield which IMO is very accurate.
At the end of the day the best test is on the road in day to day driving and I know for a fact that my car "feels" twice as fast!!!

Thinking about it, its a good job I am into this scene or I might have been driving round with low power figures all the time!! How many "normal" people have their cars RR`d on a regular basis???
Thank god for Scoobynet and R.B for sorting the days!
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Old Mar 28, 2003 | 02:03 PM
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Doc my figures are from John Nobles as well. Which I have heard are pretty good. Mine was something like 260bhp and 235lb/ft and 195bhp @ wheels car ran about 1.0bar but me and PWIG saw 1.2bar on the way home in 4th. So 260bhp on the RR with 1.0bar and actually 1.2bar under normal road conditions. Havent got a clue how this would equate though. Surely if the car runs more boost on the road it makes the RR figure under read ??
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Old Mar 28, 2003 | 02:29 PM
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Doc,

Your RR man seems to be having a bit of a prob...
The calculation for BHP is BHP=Torque(lbs/ft)*RPM / 5252.
Which means that Torque and BHP are the same at 5252 revs.
The figures you seem to have been given do not follow this rule if the torque is correct. Additionally a lower torque will produce a lower BHP for the same RPM and a lower RPM for the same torque will also give a lower BHP.
e.g.
100lbs/ft * 2000RPM/5252 = 38 BHP
100lbs/ft * 4000RPM/5252 = 76 BHP
80lbs/ft * 2000RPM/5252 = 30 BHP
80lbs/ft * 4000RPM/5252 = 61 BHP
Therefore if the boost is upped and the revs stay the same, the torque would go up and the BHP would also go up not down.

Am I making any sense?

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Old Mar 28, 2003 | 02:51 PM
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Scooby 1998S,

Yes your spot on mate. BHP is just torque at whatever rpm. Civic Type R's don't have a lot of torque so have loads of revs to get the power. Golf PD150 can't rev but has shed loads of torque to make the power.

If you want more power you need more torque or more revs. An F1 car only has the same torque as most modern TDi's but 18000rpm, nice.

If you stick to a fixed figure of say 6000rpm the only way to up the power is to up the torque.

Lee
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Old Mar 28, 2003 | 03:36 PM
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So would you advise any Scooby owner who suspects they may have a similar problem to take their car and have it RR'd?

Or would fitting a boost guage have given you an indication that something wasn't right?
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Old Mar 28, 2003 | 03:40 PM
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From: Sunny Ilson
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I may be a bit misleading with the figures because I am going off memory.
I will scan the RR graph
Thinking about it Torque may have been nearer 220 when bhp was 298
The time before was 199 torque / 260 bhp
Does that make it clearer??
i`ll scan the graph anyhow for those of you who are interested.
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Old Mar 28, 2003 | 05:52 PM
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LOL Doc I was planning a Mcrae before the last RS I had but needed money for home improvements. I need more home improvements and with the Clio I can drive it with out too many overheads. Thanks to Robertio I have driven a Scoob a fair bit so thats taken a bit of the need to go straight out and buy one away.
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Old Mar 28, 2003 | 06:58 PM
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298bhp at 6000rpm equates to ~256lbft at 6000rpm.

160bhp at 4000rpm is 210 lbft at 4000rpm. This is pretty close to what you would expect at those revs from a standard UK car. With decat and zorst and "normal" boost, something around 240lbft would be "expected" at these revs IMHO.

Either way your 298bhp/195 lbft (or even 298/220) is just plain impossible, unless it all happens at much higher revs.

It would be almost unheard of for a UK car with just a decat and induction kit to produce 298bhp at 6000rpm, especially with only 15psi. I think there are some mixed up figures here somewhere.

Edited cos there was also some mixed up english

[Edited by hades - 3/28/2003 6:59:45 PM]
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Old Mar 28, 2003 | 07:01 PM
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Carlos, don't know about the low overheads with the clio, I had a clio williams 1 without about 190 bhp, few mods and ended up with a £900 mot, track rod arm I think, or something similar at £600 plus a 2 week wait, none in the country and a power steering hose at £100. Not a happy bunny with a few minor bits making up the rest of the bill. Great car but get the scooby. Hope the clio stays cheap as mine was to expensive to keep.

Marc
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Old Mar 28, 2003 | 07:56 PM
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Just checked my graph and it says

Max torque @ 4230 rpm = 233lb/ft
Max power @ 6640 rpm = 258.5bhp


I am just guessing from the graph but

Power at 4230rpm (max torque) looks about 190bhp

Torque at 6640rpm (max bhp) looks about 203lb/ft


Just tried the calculations
based on BHP=Torque(lbs/ft)*RPM / 5252

power = (233*4230)/5252 = 188bhp

torque = (258.5*5252)/6640 = 204lb/ft

So yep the graph looks okay for me.

The funny thing is I have just looked at the graph so maybe a litte bit out

2500rpm = 58bhp and 130lb/ft

3000rpm = 91bhp and 155lb/ft

4000rpm = 175bhp and 230lb/ft

5000rpm = 220bhp and 230lb/ft

6000rpm = 250bhp and 220lb/ft

7000rpm = 255bhp and 190lb/ft

Kind of explains why it takes off when it hits just over 2500 rpm and goes all the way to 7000rpm .

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Old Mar 28, 2003 | 09:44 PM
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Marc I think the Willie's are pretty brittle and for that reason it will be staying standard. My average MPG Town driving is 30mpg so I cant compain - Yet!
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Old Mar 29, 2003 | 07:54 AM
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From: Sunny Ilson
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Right, cant scan it till monday but here goes:

298.2BHP / 6724 revs - 232.9 lbft / 6614
Boost nearly 16psi then it cut / 123 mph

The figures are from a UK car with De-Cat and induction ???
As for the graph the BHP line goes diagonally from left to right
bottom corner to top in a straight line!!!
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Old Mar 29, 2003 | 10:31 AM
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As for the graph the BHP line goes diagonally from left to right
bottom corner to top in a straight line!!!
Must have been something wrong with the dyno.

Lee
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Old Mar 29, 2003 | 01:47 PM
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Heres mine :


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Old Mar 30, 2003 | 07:39 AM
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From: Sunny Ilson
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There wasnt something wrong with the Dyno there was something wrong with the car
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Old Mar 31, 2003 | 12:47 PM
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Excellent torque figures and very smooth. I have the same with my UK spec car, nothing till 3,000 rpm and then whoosh....

Interesting to see the drag figure on CHRISP's car, my last dyno session did not show this. I assume its the run down power of the RR, in braking the transmission and diff's etc...

If anyone wants to know more about performance measurement and efi engine tuning, I would suggest looking at David Walker's book, he of CCC fame.

cheers.
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