Jake Posted February 13, 2007 Share Posted February 13, 2007 I'd like a bloody accurate reading too after getting 430 at the fly without my hybrids but losing 40% in drivetrain losses to the wheels!!!!! 40%? That can't be right. What was the RWHP figure? Quote Link to comment Share on other sites More sharing options...
silvershark44 Posted February 13, 2007 Share Posted February 13, 2007 Got a new 02 sensor sitting on my desk To be honest on the RR day everyones AFR's went off the scale except TrickTT's. Weston Performance advised most of us that fitting some kind of fuel controller would release more HP. Edit: Just re-read your post Homer and now understand you meant THEIR 02 sensor was no good! In that case the ultra rich readings we all got on the day could all be false, bugger me! Yeah that does put a whole new slant on things!! Quote Link to comment Share on other sites More sharing options...
imi Posted February 13, 2007 Share Posted February 13, 2007 40%? That can't be right. What was the RWHP figure? Easy now Jake, don't spoil all his fun, he's probably been bragging about those numbers for a few months now Quote Link to comment Share on other sites More sharing options...
imi Posted February 13, 2007 Share Posted February 13, 2007 What happened to Thor then, everyone used to recommend them before I went there - I thought a hub dyno reading would be better than any? So a message for traders in there Quote Link to comment Share on other sites More sharing options...
Homer Posted February 13, 2007 Share Posted February 13, 2007 Sounds good Greg. I'd like a bloody accurate reading too after getting 430 at the fly without my hybrids but losing 40% in drivetrain losses to the wheels!!!!! Greg, you got it the wrong way round mate, the RR works out the torque at the rear wheels, it then uses this and the engine rpm to provide a bhp figure. In turn this is then converted using a drivetrain drag factor to provide an estimated flywheel figure. If they're telling you its 40% drivetrain loss then this is a classic exmaple of a RR operator fudging the figure to provide a results you want to hear (and probably return to them in future ). Either that or they don't know how to dyno an auto. As Jake mentioned, can you provide your wheel bhp, this can then be converted using a more realistic drivetrain loss (18-22% is generally accepted as correct for the auto box, 12% for the Manual). Quote Link to comment Share on other sites More sharing options...
Bobbeh Posted February 13, 2007 Share Posted February 13, 2007 40%, what are you driving a tank? G-Force at Ayelsbury is also a good one to try. They use Dyno dynamics RR's but know how to use them. You could try Thor with a comparison with other owners for a hub figure.. I wouldnt worry about the calculated fly one tho. Burna, your figure doesnt look too far out, I would expect 250 sommat for yours for a healthy stock auto TT. Mine got 265 RWHP with 18% loss (which equated to 323bhp give or take 1% accuracy -which is spot on for a stock TT) For manuals 18% loss and up to 25% loss for autos when they measured mine. Quote Link to comment Share on other sites More sharing options...
tbourner Posted February 13, 2007 Share Posted February 13, 2007 So a message for traders in there Guess I walked into that! Quote Link to comment Share on other sites More sharing options...
michel lane Posted February 13, 2007 Share Posted February 13, 2007 does it really matter how much HP you have ??? it feels fast for you , then enjoy it ....why spend addtional amounts of money to prove a point, just use the car and have fun with it . Iam just going to take mine out for a spin, i think ill run it on low boost today as its abit damp ...500hp @ 1.3bar should be ok i think . Quote Link to comment Share on other sites More sharing options...
Bobbeh Posted February 13, 2007 Share Posted February 13, 2007 An accurate dyno sheet is a good thing as it stops you from being a billy bullshit Quote Link to comment Share on other sites More sharing options...
dangerous brain Posted February 13, 2007 Share Posted February 13, 2007 Problem is if you do get a high reading everyone instantly suspects the dyno operator of over egging the omellette. What constitutes an accurate reading and who is ultimately qualified to verify them? Quote Link to comment Share on other sites More sharing options...
Homer Posted February 13, 2007 Share Posted February 13, 2007 Problem is if you do get a high reading everyone instantly suspects the dyno operator of over egging the omellette. What constitutes an accurate reading and who is ultimately qualified to verify them? See Jakes post eariler, thats the max power at stock fp. Dyno's are only really only good for checking a cars health and checking your modifications are having the desired effect (and of course using rwhp and torque figures only to do so) Quote Link to comment Share on other sites More sharing options...
dangerous brain Posted February 13, 2007 Share Posted February 13, 2007 Will an FSE up the fuel pressure? Quote Link to comment Share on other sites More sharing options...
silvershark44 Posted February 13, 2007 Share Posted February 13, 2007 I can understand why you all say why bother having it dyno'd etc. For me it is purely to see if the thing is running properly as I have no intention of modifying it. In some ways it is a pointless exercise, but I just wanted to be sure its running ok really. It always feels fast to me and certainly is smooth. I guess the boy racer inside me wants to know some figures lol Quote Link to comment Share on other sites More sharing options...
Burna Posted February 13, 2007 Share Posted February 13, 2007 Burna, your figure doesnt look too far out, I would expect 250 sommat for yours for a healthy stock auto TT. Mine got 265 RWHP with 18% loss (which equated to 323bhp give or take 1% accuracy -which is spot on for a stock TT) For manuals 18% loss and up to 25% loss for autos when they measured mine. That's great info thanks Bobbeh I was hoping someone would explain it to me if I posted up the rwhp graph as I've always been told that is the only one which matters. Had to specifically request for the rwhp graph on the day though at Weston So if my calculations are correct, please anyone let me know if they are not: First based on Homers info. As Jake mentioned, can you provide your wheel bhp, this can then be converted using a more realistic drivetrain loss (18-22% is generally accepted as correct for the auto box, 12% for the Manual). 250rwhp with a loss of 18% = 305fwhp 250rwhp with a loss of 22% = 321fwhp Then your info Bobbeh. For manuals 18% loss and up to 25% loss for autos when they measured mine. 250rwhp with a loss of 25% = 333fwhp As you say it looks as if the car is running spot on, that's a relief But all this has made me understand where all the confusion and arguments come from over fly wheel figures when I look at the wide range from those correction values. I'll stick to rwhp figures in the future, thanks everyone for helping me to understand Quote Link to comment Share on other sites More sharing options...
Ian C Posted February 13, 2007 Share Posted February 13, 2007 250rwhp with a loss of 18% = 318fwhp That's 305fwhp akshully -Ian Quote Link to comment Share on other sites More sharing options...
Ian C Posted February 13, 2007 Share Posted February 13, 2007 Will an FSE up the fuel pressure? Sometimes, if it feels like it -Ian Quote Link to comment Share on other sites More sharing options...
RobSheffield Posted February 13, 2007 Share Posted February 13, 2007 Sometimes, if it feels like it -Ian good point well made Quote Link to comment Share on other sites More sharing options...
Sheefa Posted February 13, 2007 Share Posted February 13, 2007 Hi guys (and piss of Imi! ), here was my dyno result. Yeah, it looks like the flywheel hp has been egged up a tad! 430 on STOCK tubbies. I haven't had the car dyno'd on the new hybrids yet or with FMIC fitted. Any views on the graph? Losses or strange readings? 285rwhp and over 420fwhp. Cheers all. Greg Quote Link to comment Share on other sites More sharing options...
Burna Posted February 13, 2007 Share Posted February 13, 2007 That's 305fwhp akshully -Ian Thanks Ian Knew I would get one wrong but it seems I finally understand it all Only took my 1500 posts too I've edited my post so it all works out. Quote Link to comment Share on other sites More sharing options...
Dragonlady Posted February 13, 2007 Author Share Posted February 13, 2007 Hello all, Just got in from work, switched on computer......."Oh sh*t, it's still on going" Sorry if I have caused any probs or arguments, didn't mean to. I noticed that people are saying that rwhp is the one to go by, if this is the case we got 375.7 on the RR day which would equate to? ( brain dead after long day) Also "if" we were running rich at an AFR of 9.9 and had this sorted, what sort of power increase would you expect to gain? Thanks Quote Link to comment Share on other sites More sharing options...
imi Posted February 13, 2007 Share Posted February 13, 2007 Will an FSE up the fuel pressure? not after it spills fuel all over your engine bay..... Quote Link to comment Share on other sites More sharing options...
imi Posted February 13, 2007 Share Posted February 13, 2007 I noticed that people are saying that rwhp is the one to go by, if this is the case we got 375.7 on the RR day which would Well DragonLady - in your case with stock injectors and a standard FPR (as we know now) that is simply not possible...hybrids or no hybrids, standard or not a standard engine. You simply don't have the fuelling to cater for that sort of power. Like I said - i'll be giving weston a miss Quote Link to comment Share on other sites More sharing options...
imi Posted February 13, 2007 Share Posted February 13, 2007 Hi guys (and piss of Imi! ), here was my dyno result. Yeah, it looks like the flywheel hp has been egged up a tad! 430 on STOCK tubbies. I haven't had the car dyno'd on the new hybrids yet or with FMIC fitted. Any views on the graph? Losses or strange readings? 285rwhp and over 420fwhp. Cheers all. Greg Looks pretty good that Greg Nice smooth Power curve and a healthy amount of torque to go with it. How did they smoothen the power delivery so much (thats certainly not the case with the quicker J-spec turbos) imi 285 @ the wheels no way equates to anything close to 420 @ the fly - more like 350 ish if you have an auto. In any case - seems like you have a strong motor there. Quote Link to comment Share on other sites More sharing options...
Burna Posted February 13, 2007 Share Posted February 13, 2007 285rwhp and over 420fwhp Greg I worked them out to this, hope if it helps 285rwhp with a loss of 18% = 348fwhp 285rwhp with a loss of 22% = 366fwhp 285rwhp with a loss of 25% = 380fwhp Quote Link to comment Share on other sites More sharing options...
Bobbeh Posted February 13, 2007 Share Posted February 13, 2007 That's great info thanks Bobbeh I was hoping someone would explain it to me if I posted up the rwhp graph as I've always been told that is the only one which matters. Had to specifically request for the rwhp graph on the day though at Weston I'll stick to rwhp figures in the future, thanks everyone for helping me to understand Thats the best thing to do, at least that way we all have results from similar dynos that havent been interprited by someone with whacky loss figures thrown around for good measure/fudging. I mean if everyone used the same type, or place we could all kind of benchmark it against everyone else. Quote Link to comment Share on other sites More sharing options...
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