Porsche Enthusiasts Club Forum

I know I'm probably setting myself up for a fall/disapointment here but before I consider making any modifications to my car it seems obvious that I should find out what she is putting out at the moment. I have found a place near Royston that does the usual race prep , boy racer car tuning etc and has a resonably modern rolling road so for only 45 pounds ! , I thought I'd give them a go tomorrow lunchtime.

I will post the result here so you can all have a good laugh but what do we think , will she make 220 plus or will I be crying in my milk and cookies before bedtime ?

For fun would anyone like to post a guess at the result , I'm going to go for 220 as a complete cop out

Spec: 87 944 turbo 110,000 miles. Not chipped . Fitted with Lindsey racing boost enhancer ( set at standard I'm told ) , induction kit and Bailey dump Valve.

Regards Mas

Mas - Good luck with this. You are a braver man than me.
I reckon you will be surprised. These cars left the factory with more power than quoted. Porsche figures in general are always reserved. Cars top speed is often at least 10 mph under what it actually can do.

I'm going for 207bhp as a finger in the air guess.

I wish i had the balls to take my car on a RR.

Mas

I bet that boost enhancer is turned up a little, I'm going for 230 hp.

My Turbo S had been standing for some time when I bought it and having done about 90k miles made 247 hp which I was well pleased about.

It would be worth giving your vaccum lines a look over before going.

Rich

That's a good point Rich , TBH I wouldnt even know which lines to check. I do know there are replacement thin blue silicon lines under the bonnet so presumably the prior owner gave some thought to that ?. If you have any specific ones I should check I'd be pleased to ( I havnt much idea whats what under there TBH) . This is what it looks like at the mo anyway.



I am of a mind purely for the interest to do the rolling road then go to promax for a chipping and fuel pressure regulator and then publish the difference for the interest of myself and others but only if the car is putting out fair power as it is. We'll see.

Cheers

Mas

Use the same dyno for before & after & you can measure the difference. Actual power depends on the dyno. More inflate than are true sadly. Power at wheels is what counts. You can get any figure you want once you start correcting it. 210 at the wheels would OEM. Be interested to see the result. Make sure they check the fueling first.

Having read your post J.J and knowing nothing re dyno testing I had a quick read up. As you say power at the wheels is obviously the accurate figure but manufacturers are all quoting at the flywheel. So my car 'should' when new have produced 220 at the fly but thats 'about' 183 at the wheels right ? . Surely if my car was 210 at the wheels that would be a miracle wouldnt it.

So all the other folk on the forums etc are quoting they have 260 or 310 BHP 944's but I assume they are all quoting flywheel figures ' estimated ' after their dyno runs since a dyno cant measure the flywheel figure. Just so I know am I getting this right. ?

Cheers Mas

Just after I bought mine the region had a rolling road day in Warrington, so on it went. Completely standard, it should have been 250bhp but it only achieved 227bhp. Not bad I thought for 20 year old engine, but I think the DPW and EBC have helped put that right, just not taken it back to check.

IMO, 210 at the wheels would be wishful thinking. I'd agree with Mas' claim of 180ish being around right. Even a new car with nothing extra (i.e no PAS, AC etc.) will still lose about 30% at least before it hits the rear wheels.

We didnt get as far as a power run. In short this is going to need its own topic so please read the overfuelling post especially if you know anything about tuning these cars



Regards Mas

Mine does 140 at the wheels stock. Add 30% to that! Think about it . If your losing 30% wheres it going. If it's friction then it would catch fire! Look at Ricks performance league for a guide. 250 at the flywheel is 210 stock if it's all bang on. Well you know now that it's not Mas. Well thats why my car eats S2's. Most can not match the book figures by a long way. If you look at the figures for cars that are 3 years old they tell a story. One small fault = lost HP Problem is finding it!

Edit. Top man Mass for coming on here & admiting it. You will get it right & boy will it feel good when you do. And kill all those Cupra sports & Audi TDI's

I was only basing my figures from previoius cars. My Focus made 63BHP at the wheels (a 100BHP 1.6), an old Ka I had made 38BHP (58BHP stock) and that was 2 years old back then. Lowest losses I had was on my last car a Pug 306 GTi-6 which made 142BHP at the wheels and around 167BHP at the crank. Considering the 944 has more potential areas for loss (with it being RWD), that's how I arrived at my figure. I would guestimate that the S2 probably makes around 150ish at the wheels, with it being quicker than the 306 was, and shifting better despite a 100kg penalty over the 306.

S2's make 180-185 at wheels when fit. The actual figures are not important though. The point of the dyno is to check your fuel ratio throughout the rev range & see that everything is as it should be. Mine had a duff FPR that was costing nearly 30 hp. Without the dyno I wouldn't have known! It's always difficult to compare figures unless using the same dyno as they are not all the same. Though they should be! A Ford Gt 40 made 240 at the wheels & a Honda S2000 200 on the same dyno (Before mapping.) I put mine on. Many cars don't live up to there figures even when new. So 140 on this dyno is good! But the man says theres more in there yet. We will see.

So why do you think rear wheel drive is less efficient??

Exactly it shouldn't be, although from my experience tyres make a big difference as well.

Quote J.J " Top man Mass for coming on here & admiting it. You will get it right & boy will it feel good when you do. And kill all those Cupra sports & Audi TDI's "

I may be a funny stick in some ways J.J but I cant stand bulls poo, with me you 'always' get the truth though sadly not everyone wants that of course

I will report back after Promax and after a proper Rolling Road session !

Thanks all

Mas