boabster

just got my car rolling roaded today and was shocked at the result?
164 bhp at the wheels so only around 200 bhp
i only just got the car 2 months ago and was curious as to its power?
its got a k and n induction kit thats getting binned wene i get the original air bok on tuesday but that doesnt account for the other 40 bhp thats still missing its a 93 wrx.....they put the chassis numbder into the computer and it said it came into the country with 240.bhp
does anyone have any sudgestions were all tha power is missing???????

Butty

iTrader: (2)

36 bhp transmission losses is on the low side - but it depends on whose RR you used.

If you flick through the results on http://dyno.scoobynet.co.uk/ you'll find that 164 @ wheels is more or less 240 bhp - so I'd say that you're worrying unduly.

Nick

boabster

cheers nick puts my mind at ease.....was worrying there

Floyd

iTrader: (9)

Lucky you! I had 100 BHP ATW

F

theotherphil

Surely 100BHP ATW (or even 164BHP ATW) can't be right for a scooby? I had a 2.0 16V Nova pushing 155BHP ATW and a Golf VR6 giving 169BHP ATW....both with minimal mods (air filter, exhaust & ECU remap). I didn't realise 4x4 made such an impact....my scoob certainly feels quicker; I suppose the extra traction helps though!

NotoriousREV

a JDM WRX is rated at 240ps running on JDM 100 ron fuel when new. Add some engine wear and 98 ron fuel and 220bhp at the fly is more realistic which given 1/3 loss through the tranny would give 165 ATW. Sounds about right to me.

preza si

had my scoob RR yesterday aswell at powerstation, its a my99 uk turbo with centre decat and afterburner vortex back bock and a bleed valve which is running 15psi. it came out at 219bph with 132.5bph at the wheels and 212lb. does that seem right? need more power tho, got a comp on with my mates mr2 turbo, need to beat him!!!

TonyBurns

iTrader: (3)

I prefer it when you get 255bhp@wheels and just under 300bhp@fly
Must be something to do with the diff

Tony

Fangoria

iTrader: (1)

preza si

That is very low - but its PS - they have no correction for the high temps in the summer.......... Between winter and summer at PS power figures can vary by over 50bhp...........

Plus their rollers read lower than anywhere else in the UK.............

Go to Well Lane or Star Performance and you'll feel much better

Tony

Not bad numbers........ when I'm next up in Yorkshire I'll ahve to take you out in a proper performance car ............(mine should be around 500bhp on a 2 litre now)

TonyBurns

iTrader: (3)

Oh yes that sounds pretty good

Tony

Fangoria

iTrader: (1)

DURRRHHHHHHHHHH did someones last post just disappear there!!!!!!!

wheels out of alignment effects power............. damn that means I must have 600bhp then ................................... - Must remember that one at the next RR - theres a new 'spurious' excuse each time - but this one is new to me and total cobblers..............

I do take the RR numbers with a fair bit of scepticisim as the RR's vary so much on day and by RR........ G force its pretty consistent though - PS/Well Lane are definately NOT (Well Lane is not so bad for lower end powered cars - i.e. less than 400bhp - above that the rollers appear less consistent)............. but its always interesting to see what the same rollers read after mods.........i.e. Turbo changes..... (depends what Lamda your running anyway......need a nice lean Lamda for the winter and will see what I get at G Force..........)

Tony

I've heard so much hype about these spec C's - would certainly be interested to see what its all about.............

preza si

so you reckon it would read more at another RR place. also have now fitted the front decat pipe so should be a little more. which is the best place to go do u think and where abouts is it. since i've fitted the front pipe the car cuts out now some times at junctions any idea what it could be, or does it just need a re-map? thanks simon

Andy.F

lol @ Steve P/S rollers are the same as Stars !

Andy

Fangoria

iTrader: (1)

Depends if u want high numbers or accurate no's

Go to Well Lane in Batley ( W Yorks) if you want a nice number (they overstate significantly but consistently overstate so if your car feels fatsre it will get more on these rollers (have been using the rollers since 1990)....... go to G Force in Aylesbury if you want an accurate number

But wait until winter time when your fuellings a bit leaner.......... your number will be much higher......... then again see below!!

Your running a bleed valve and an exhaust system.......and you went on the rollers at PS - jeez you must have deep pockets.............

Running a bleed valve is BAD period....... extra boost with no extra fuelling - bet it misfires occasionally, especially with an exhaust it could be running even leaner (more air, same fuelling, ECU cant compensate cos the Bleed Valve bypasses it)

And on a 93 car.......you have a death wish for the car


At the very least you need fuel/boost controllers and better still something like a Link ECU - you would feel the diff on the road immediately

PS is the worst roller you can go on for your set up - they run the car up on the rollers for ages = puts a lot of strain on the motor and increases the engine bya temps - results in lower power - but its fairly consistently low - if its a local one just stick with it

But!!! - dont take any notice of most peoples numbers..........theres so much crap floating about

I have not Yet been in a Scoob that I would say had over a real 500bhp......not in a 2 litre anyway............

Andy.F

Just picked out the wrong bits here

Steve, you have had a link for too long

The std ecu WILL NOT run leaner in winter, it measures mass air flow and therefore will actually run slightly richer as it accesses higher value areas of the fuel map.

Extra boost WILL result in extra fueling, the bleed valve only bleeds from the wg actuator.

The exhaust WILL NOT make it leaner unless your fuel pump cannot actually cope with the extra flow, at your level of power this is unlikely.

Andy

Fangoria

iTrader: (1)

Andy

Must be thinking about my car - dont use a mass air flow sensor..............

mine will be leaner in the winter........ scientific fact......... but ok I guess if your running a standard ecu.........that will compensate........

Re boost - well I used one of these on a Cossie (for a very short while) it was truly awful.......... extra boost with no extra fuelling - that is what a bleed valve did/does......... so your saying that they are different on Scoobs

Same with the exhaust......... ran leaner on my cossie - these Scoobs must have more sophisticated ECU's - even 1993 ones?

john banks

Doesn't matter what method you use to raise boost, if the ECU inputs and outputs are not saturated because they are out of range - either mechanically in terms of fuel pump, or electrically in terms of injector duty cycle or MAF or MAP voltage, or artificially with fuel cut defenders or piggyback modifiers, then any MAF based Subaru ECU will attempt to fuel for it and usually do an excellent job. Speed density ECUs should as well, but without temperature compensation the mixture will vary with charge temperature. Speed density will also need to be remapped for VE changes.

As an example, my Subaru ECU running off MAF was not reflashed and the engine size was increased by 463cc and it fuelled very nicely except for being a bit lean at idle. The ignition was slightly retarded as the load signal was airflow not MAP, but out the box running off the wrong map it managed about 400 BHP without any mapping at all. If you had done this with speed density, the ignition would have been nearer but the fuelling would have been way too lean.
The hazards with MAF based ECUs are sensor reliability and inlet tract modification ahead of the MAF which recalibrates the sensor, as well as flow reversions with very high boost and long intercooler pipework/chuffing dump valves. They don't even seem to be that restrictive, and are a hell of a lot easier to map for.

Turbo_Steve

In fairness, my std ECU ran a little leaner with an exhaust and airfilter on as well: not throughout the range, just as it came on boost, once the factory boost target had been reached, it seemed okay. I think it's because you're improving engine breathing, which enables earlier spool, which means more boost earlier, which in open loop the ECU doesn't have an allowance for. It certainly showed on the AFR and even a flicker of green on the old knocklink as the revs hit about 2800rpms (0.6Bar) which was 200rpms earlier than it used to be!!!

However, this is marginal as the amount of time it is in this state is minimal: once it's settled to the boost target, the fuel / air mix is all set...all the way up to fuel cut

(though I actually find the fuelling at 1.05Bar completely inadequate, lean AFRS, lot's of det, but not fuel cut until 1.1Bar?)

preza si

so, is mine ok?? by the way its a my99 not a 93 so a bit of difference there maybe, dont know. a maf?? completly lost me there, only new to all this so trying to pick all this up! is there any thing that i can do to stop it cutting out on idal? also has a bailey dump valve fitted, dont think i mentioned that before. there is also a little smell of fuel out the back, dont know if this is normal when u have no cats on there.

Andy.F

Steve

The Cossie runs speed density as std (same as the link) thats why it wouldn't compensate for a bleed valve or exhaust change.
Oh and you may well have been above the OE map sensor limit which is only 1 bar on the early cossies.

Turbo Steve - You said "I think it's because you're improving engine breathing, which enables earlier spool, which means more boost earlier, which in open loop the ECU doesn't have an allowance for."
The ECU still controls the fuel in relation to air flow, increase air flow and you increase fuel - period. The fact it is running open loop only means that it doesn't seek stoich mix, this is only ideal when under cruise conditions anyway and would be way too lean for power situations.
I suggest your fueling issues are caused by the airfilter you fitted, as JB stated, this upsets the mafs measured airflow and 'anything can happen' ....beware !

Andy

Turbo_Steve

Wideband AFR looks good, so I don't think it's the filter: purely happens during spool up.
MAF is just great (even after 200,000miles...60,000 with airfilter) so don't think it's that either. ECU lambda is in need of a change, but as you say, it's completely ignored in open-loop so it isn't that.