Dyno Day Sat 25th Oct

[pauljmcnulty]

Hi Edd, I know that putting a little smiley face in is supposed to indicate that a post is jokey and not to be taken seriously. Trouble is that many Club members here aren't regular forum users and don't understand this. The threats to close the forum, or at the very least close it to non-members, was because a lot of members didn't like the tone of some threads, and we can't give them the excuse to have a go at us again. If you don't know what smileys are (and people have the right to use the forums even if they're not computer experts) then your comments could have been seen as outside the spirit of this particular forum. Please remember that we have to keep everyone happy here, and not allow people to accuse us of turning into Pistonheads (especially the people who pay to maintain this forum). I get regular messages from people who don't like the tone of a post, or a percieved advert in a thread etc. Sorry to pick on your post, but it came across wrong to me which means it would have come across wrong to others.

 

[944Turbo]

ORIGINAL: Copperman05 I dont think the dyno results were out, seemed pretty spot on to me, the S2's mostly loosing 16-20hp after 18-20 years would seem very resonable, and surely more believable than one showing very near the original stated output. We all know engines lose power over time and especially mileage. But then I guess if I had spent a few 1000 £££ on upgrades I would be blaming the dyno for poor results too[]. Perhaps nextime Paul should find one (dyno) that provides more favouable readings. [:-] Edd

Mainly commenting because the former rollers of truth last year the S2's all had close to or higher than original power, some were there this year as well and had lost there power over 12 months - the first year we ran there IIRC the s2's were in the 200 -210 area. My car dynoed at 340 ish at 18 psi there (weltmeister), now with a better flowing IC, hard pipe, better mixture and an accidental 22psi I lost 15odd bhp, which doesn't make sense to me. Ok I now have scores in a bore but it wasn't producing oil smoke. At the end of the day my car produced more power than all the other 2.5 turbos, but my feeling is if you took a standard brand new car it would also be down on power on that day. About 10% I would wager. Anyway the reason we started having a DD was to create a direct comparison between cars on the same day, we had just found at weltmeister the same cars could be repeatedly tested to the same level on different days which is usefull. Anyway it was a good day and spurred me on to get some much needed work done on my car. Thanks again to Paul and to Jon and the team for the BBQ.

 

[Fen]

Blow me down, you got round to fitting the IC and hard pipes!

 

[944Turbo]

IC and one hard pipe have been in for at least 6 months and seemed to make a big improvement, with the other mods I think they were a big restriction. Still holding off on the one with the Tial as I think I might have to play with the springs to get the opening right, plus as I was already running rich i thought I might end up igniting the rear spoiler

 

[Copperman05]

ORIGINAL: pauljmcnulty Hi Edd, I know that putting a little smiley face in is supposed to indicate that a post is jokey and not to be taken seriously. Trouble is that many Club members here aren't regular forum users and don't understand this. The threats to close the forum, or at the very least close it to non-members, was because a lot of members didn't like the tone of some threads, and we can't give them the excuse to have a go at us again. If you don't know what smileys are (and people have the right to use the forums even if they're not computer experts) then your comments could have been seen as outside the spirit of this particular forum. Please remember that we have to keep everyone happy here, and not allow people to accuse us of turning into Pistonheads (especially the people who pay to maintain this forum). I get regular messages from people who don't like the tone of a post, or a percieved advert in a thread etc. Sorry to pick on your post, but it came across wrong to me which means it would have come across wrong to others.

Well if I did offend anyone I appologise whole heartedly, that certainly wasn't my intention. I did attend the event and saw most of the cars running that day, spoke to many people about the cars, mods, etc, my S2 was also on. I will refrain from making these remarks in future. Edd PS I am also a PCGB member even if it doesnt say so in the top left corner.

 

[Copperman05]

ORIGINAL: 944Turbo

ORIGINAL: Copperman05 I dont think the dyno results were out, seemed pretty spot on to me, the S2's mostly loosing 16-20hp after 18-20 years would seem very resonable, and surely more believable than one showing very near the original stated output. We all know engines lose power over time and especially mileage. But then I guess if I had spent a few 1000 £££ on upgrades I would be blaming the dyno for poor results too[]. Perhaps nextime Paul should find one (dyno) that provides more favouable readings. [:-] Edd

Mainly commenting because the former rollers of truth last year the S2's all had close to or higher than original power, some were there this year as well and had lost there power over 12 months - the first year we ran there IIRC the s2's were in the 200 -210 area. My car dynoed at 340 ish at 18 psi there (weltmeister), now with a better flowing IC, hard pipe, better mixture and an accidental 22psi I lost 15odd bhp, which doesn't make sense to me. Ok I now have scores in a bore but it wasn't producing oil smoke. At the end of the day my car produced more power than all the other 2.5 turbos, but my feeling is if you took a standard brand new car it would also be down on power on that day. About 10% I would wager. Anyway the reason we started having a DD was to create a direct comparison between cars on the same day, we had just found at weltmeister the same cars could be repeatedly tested to the same level on different days which is usefull. Anyway it was a good day and spurred me on to get some much needed work done on my car. Thanks again to Paul and to Jon and the team for the BBQ.

Well I certainly enjoyed myself even if we disagree on the results! Ditto many thanks to Paul for organising it, was great speaking to so many like minded people. Would def go again if allowed! Edd

 

[Fen]

ORIGINAL: 944Turbo IC and one hard pipe have been in for at least 6 months and seemed to make a big improvement, with the other mods I think they were a big restriction. Still holding off on the one with the Tial as I think I might have to play with the springs to get the opening right, plus as I was already running rich i thought I might end up igniting the rear spoiler

Just fit a bridge spoiler and get on with it [] It opened for me, but it needs quite a large section line to move the volume in the chamber quickly - it didn't open on the silicone vac line I tried first. Springing it a bit softer wouldn't hurt though I guess.

 

[sawood12]

My original comments about my surprise at the difference in results was not with regards to any disappointment I would have probably felt at the results, but that it seems daft that there should be such a large error between rolling roads. I know exactly what improvements my mods to date have provided as i've always done back-to-back dyno runs on the same dyno. However with such a variation in numbers then dyno's as absolute measurement tools loose credibility. Maybe they should not use units we all understand like BHP and Torque, but use made up units specific to the dyno - like Googlies and Wooglies on one dyno and wibbly and wobblies on another. 1bhp is a unit of energy which is 753KWso if a dyno is not calibrated to measure within a certain tolerance then they shouldn't be using the standard units. We'd all be a bit p'd off if we thought we were being short changed at one petrol station only for the manager to say - oh, our litres are a bit smaller than the litres sold at the petrol station accross the road - but ours are the correct ones, honest.

 

[Fen]

I like the petrol analogy, but it's a bit like buying fuel by the litre when the pump can only determine quantity by measuring the light transmission from a bulb of known power through a depth of the fuel held in a vessel of known surface area. In other words it's such a convoluted extrapolation that the compounding of margins of error can result in the figures being far apart. If I recall correctly DynoDynamics measure in a native unit called "tractive effort" or similar. I wouldn't be surprised to find that that raw number is much closer between the Weltmeister dyno and the one you used on Saturday and that the difference is amplified by small differences in the factors involved in the calculation that produces units we understand.

 

[will lyons]

Visiting this Dyno and the results for my car has set me on the modifying road already looking at where I have a boost leak, to be honest I had bareley noticed in day to day running as the Turbo comes in and has seemed to do what it is meant to,either way if there is a problem then I want to sort it and as I have always said I WILL upgrade replacement parts with after market ones to improve performance as long as I continue to own the car and I am already looking at replacing the wastegate with a Tial unit and EBC. As the guys who were there know the BOV was replaced with a Bailey unit I have noticed a difference already with only that. Since Saturday I have been trying to make sense of the Graphs and figures comprising last years result of 216.5 bhpWeltmiester to Saturdays result of 194.5 bhp. Interesting enough it is a difference of 22 bhp which is what we are all saying and......... as Fen asked did anyone run a standard car Mine is apart from the bailey unit and a Panel K&N. Weltmiester said I was running rich last year and expected a little more..... Emmisions were out for the MOT and Triton also told me still rich running and further suspect a boost leak which may be the wastegate If I modify I would lose the benchmark of a standard car for comparison if I keep it standard it would be greater expense so for me the obvious route is to modify as I correct any problems which may be there ... A thought would be to re-run at Weltmiester to compare accuracy BEFORE I do anything to the standard set up which I would be happy to do. This would also provide a baseline for comparison of modifications for me within a more reasonable travelling distance and possibly only possibly show if the 20 Bhp is a difference in the machines . my car standard should produce 220 bhp weltmiester was 216.5 and the boost leak may well have been there last year Triton 194.5 is 25.5 hp down on standard, do you think I should book on at weltmiester ASAP to compare ????? Wil edited to remove keyboard gremlins

 

[rcsalmons]

Will Unfortunately the Weltmeister dyno is no longer there but Chris is running a DD dyno in Wellingborough which has been tested against Weltmeister with comparible results. My car ran 294hp in Wellingborough and 274hp at the weekend - the car still seems the same though. If you go to Wellingborough let me know I will come along -its 15mins from M1 J15. Rich

 

[Neil Haughey]

Any chassis dyno that isn't a pile of junk should very accurately measure the power applied by the tyres to the rollers at the time the measurement is made. In its most basic form a roller is just a large heavy drum, its acceleration is a direct measure of the torque applied to it by your car, the cars power is just the torque multiplied out by the rpm's in the engine (power is just rate at which energy is produced). Boils down to simple physics really. Problem is that extrapolating the raw figures at the drum up to engine power outputs at the flywheel involves lots of conversion parameters to take into account amongst other things, the environmental conditions. There is an SAE standard that I can't remember the number for that describes this, ppl will also argue about the validity of using coast down to get the transmission losses. Worth remembering as well that tyres supposedly (?) make a big difference as well, hence the proliferation of hub mounted dyno's.

 

[Diver944]

I've solved it [] It's this credit crunch thingy. We all know that house prices are shrinking and I bet that dyno horses are linked into the housing market, so as each month goes by our horses are getting smaller and smaller Oh dear Will you are at the top of a slippery slope []. Save your money on upgrades and take your car to Jammsport here in Northampton. I bet you will be close to 250bhp without having to fit any mods at all. Rick, how is the upload of the charts going?

 

[AndrewS]

ORIGINAL: will lyons ...my car standard should produce 220 bhp weltmiester was 216.5 and the boost leak may well have been there last year Triton 194.5 is 25.5 hp down on standard, do you think I should book on at weltmiester ASAP to compare ????? Wil

Hi Wil, Personally, I would not be concerned about power figures from the recent Dyno run (as everybody had lower than expected results). Go to another Dyno and you will get different figures. What I would recommend is a boost leak pressure test and also a cylinder pressure test and leak down to ensure you are making good compression without loss (past rings or valve guides). Check over all your vacuum connections to make sure they are secure. Another useful test would be an AFR (Air Fuel Ratio) test using an exhaust mounted O2 sensor and suitably callibrated measuring equipment to make sure that you are getting readings within tolerance (whilst the car is driven on the road). I doubt there is much wrong and if you do start on the road to modification; have a specific objective to work through and ask around to see what has worked for others. The above tests are merely to confirm you have a solid base to work from. Regards, Andrew

 

[homesea]

Rich I have sent you an email about your spare chips, have you got it?

 

[pauly]

ORIGINAL: homesea Rich I have sent you an email about your spare chips, have you got it?

I did too, [8|].

 

[homesea]

Dam you Paul!!![:'(] Did you see my post about the wastegate? I think you need one of them 1st.[]

 

[Peter Empson]

Bit belatedly, but I want to thank Paul for arranging the dyno day. I've not seen such frenzied work in the car park at one of these events before (nor have I seen exhaust sniffing going on either []). It's good to be back where I belong, right at the bottom of the power charts (although to be fair I think I might be both at the bottom and the top of the 944 NA chart simultaneously ).

 

[pauly]

ORIGINAL: homesea Dam you Paul!!![:'(] Did you see my post about the wastegate? I think you need one of them 1st.[]

[] There's a few upgrades to sort out on my car but I'm not in any rush, if I buy parts now they will probably sit on a shelf in the garage until next spring so no problem if you want the chips. [].

 

[starboard147]

Some phots of the day here: http://picasaweb.google.com/mjs019/Dyno_day_25Oct#