Low HP reading at Dyno yesterday
#31
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Oh and sorry about this Wayne. My feeling is that while your power figure isn't too far from reality the comparisons with your friends car with similar mods and that he leaves you behind does suggest something isn't quite right.
We should get back to the program here and help this guy out. My apologies for getting OT.
We should get back to the program here and help this guy out. My apologies for getting OT.
#32
It does look like those charts are in 3rd gear as 160kmh is 98mph which will be 6500rpm in 3rd or 4600rpm in 4th as ST says. However I have run my car back to back in 3rd and 4th gear on a Dyno Dynamics and it makes not one jot of difference. The Dyno Dynamics are sophisticated pieces of kit (for an Aussie design ) and the runs are all within 1% of each other no matter what gear you are in.
200RWP for a K26/6 with minor mods is a little low but not drastically so. When my car was a 2.5 with K26/6, TiAL WG and guru chips at 15psi I recorded 230WHP on a Dyno Dynamics.
We all know that you just cannot compare dyno results from one shop to another with the same dyno, let alone different dynos as you will get widely varying results, but they are useful to provide an approximation. Whatever happened to that old thread where we were going to get some video logs of 4th gear roll on runs from 2000rpm to 6500rpm out on a real road? That would provide a definitive comparison of how our cars are running around the world
200RWP for a K26/6 with minor mods is a little low but not drastically so. When my car was a 2.5 with K26/6, TiAL WG and guru chips at 15psi I recorded 230WHP on a Dyno Dynamics.
We all know that you just cannot compare dyno results from one shop to another with the same dyno, let alone different dynos as you will get widely varying results, but they are useful to provide an approximation. Whatever happened to that old thread where we were going to get some video logs of 4th gear roll on runs from 2000rpm to 6500rpm out on a real road? That would provide a definitive comparison of how our cars are running around the world
Last edited by Diver944; 11-28-2007 at 12:12 PM. Reason: typo
#33
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That's pretty interesting right there Paul. Approx crank 45hp increase with basically just chips? That seems high to me so maybe it's not just a US thing lol. Maybe I'm just wrong too of course but I would have thought you would need a bit more than 15psi to get that sort of increase. Wayne has got more mods than you at that stage so it would seem something is up?
#34
It's hard reading those charts as the rpm line is road speed in KMH, but if you look at the boost chart which has a max of 14.5 psi you can see that it spools very s.l.o.w.l.y. for a K26/6 It doesn't even hit 14psi until 135kmh which is 5500rpm according to my chart. My comparison car made 15psi by 3300rpm with it's K26/6
Makes me think a heck of a lot of boost is being lost somewhere or the wastegate is opening waaaaay too early. Could the BOV be leaking THAT much
#35
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3rd to 4th gear on a nearly stock car will make hardly any difference. 10hp at the most. Typically I run every dyno in 3rd and 4th and give them to the owners because I got tired of hearing....you should have run it in 4th....or 3rd, lol. Then they see that there isn't that big of a difference and they can pick which ever one suits their ego.
#36
I used to operate a Dyno Dynamics when we had one at the shop, they read lower than any other dyno I have seen. Dynos are good for comparisons using the same Dyno, not comparing to other peoples dyno numbers on different dynos.
#38
Race Car
I have seen so many times where (especially stock 951) drivers look at the boost guage at the peak and assume it stays there, when in reality it will drop, significantly in some cases.
One may think they are running 15psi but then in reality it has dropped to 10 after 4000 rpm. An MBC really accentuates this.
#39
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#40
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What, you set your alarm for this? What time is it there? I thought you may be the first to respond, or A Wayne, but you're right in that the car did have a glitch, but I'm telling you it pulled damn hard when this glitch didn't happen. I don't have much experience with a 500+whp car either so you're right again, but it was much stronger than my 2.5L with chips and 22 psi so I dunno what to say?? I am also reflecting what every other nation thinks about US dynos to a greater or lesser degree. I know that there is no way of making this sound anything but belittling, but that's not my intention. Equally, there is no way that Lart's car with chips and a wastegate was getting 260whp unless it was run at 30+psi and even then I don't think that the K26/6 would support this so what can I say.
I am not doubting your recent success nor am I having a go at the entire US nation...god forbid, wars have started for less and we've just thrown out our US supporting Govt. so please don't attack us. lol
As for our dinner date, I'll be wearing a pink carnation in my lapel and I believe I'm to look for a solid specimen carrying a polish sausage?? Is that right?
I am not doubting your recent success nor am I having a go at the entire US nation...god forbid, wars have started for less and we've just thrown out our US supporting Govt. so please don't attack us. lol
As for our dinner date, I'll be wearing a pink carnation in my lapel and I believe I'm to look for a solid specimen carrying a polish sausage?? Is that right?
#41
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Agree 100%. I had my 951 on three different dynos and there was a spread of over 50 rwhp from the lowest to highest hp numbers. Dynos should be used as tuning tools, not for comparing numbers to other vehicles.
#42
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See, this just exemplifies what we ROW's say about US dyno's. There's no way that a k26/6 with just chips and gate could do 260whp. That is 300crank when the stock one brand new at it's peak did 220hp.
Just as an example, with a 3.0L conversion, Vitesse stage 5 kit, modified inlet, larger exhaust, large frontmount i/c did 275whp. Now granted this is on a notoriously low reading dyno. We think as this guy races vintage cars that he reads low so as not to get any weight penalties, however add 20% (which is outlandish) and you still only get 330 at the wheels. This was with the standard head/cam (not with the CEP racehead/cam) and I hope to dyno the system as a whole once I get the interim 3.0L block, but everyone in the US was saying that with those mods I should be seeing min. 350-400whp. Let me tell you folks, nowhere near. To be fair, I did have the occasional glitch that cut everything off mid burst, but this was not common, and apart from that, the car pulled like a rocket. So it certainly didn't feel weak. Yet there you have it 275whp, 4th gear, all those mods. I would bet a small fortune that if I was to teleport the car on that same day to a US dyno, that it would pull way higher figures. Hey that may have happened had I gone to another Aussie dyno too. I will try that when we're back on the road again too, just to satisfy all concerned.
Now I'm not the only one who has noticed this. To be honest, and no disrespect intended, most of us are at a loss to explain why US cars get such high dyno reads compared to cars with similar mods??
Go figure. This will open a can of worms, as it has in the past, but where there's smoke there's fire. This is from many countries around the world that just can't understand why there is so much difference. Of course you can load up a dyno to read virtually anything you want, but what gives???
I think that WW's 200whp with a k26/6 sounds not that far from reality. May be a glitch somewhere, but a approx. 10% rise in power from stock seems about right.
Just as an example, with a 3.0L conversion, Vitesse stage 5 kit, modified inlet, larger exhaust, large frontmount i/c did 275whp. Now granted this is on a notoriously low reading dyno. We think as this guy races vintage cars that he reads low so as not to get any weight penalties, however add 20% (which is outlandish) and you still only get 330 at the wheels. This was with the standard head/cam (not with the CEP racehead/cam) and I hope to dyno the system as a whole once I get the interim 3.0L block, but everyone in the US was saying that with those mods I should be seeing min. 350-400whp. Let me tell you folks, nowhere near. To be fair, I did have the occasional glitch that cut everything off mid burst, but this was not common, and apart from that, the car pulled like a rocket. So it certainly didn't feel weak. Yet there you have it 275whp, 4th gear, all those mods. I would bet a small fortune that if I was to teleport the car on that same day to a US dyno, that it would pull way higher figures. Hey that may have happened had I gone to another Aussie dyno too. I will try that when we're back on the road again too, just to satisfy all concerned.
Now I'm not the only one who has noticed this. To be honest, and no disrespect intended, most of us are at a loss to explain why US cars get such high dyno reads compared to cars with similar mods??
Go figure. This will open a can of worms, as it has in the past, but where there's smoke there's fire. This is from many countries around the world that just can't understand why there is so much difference. Of course you can load up a dyno to read virtually anything you want, but what gives???
I think that WW's 200whp with a k26/6 sounds not that far from reality. May be a glitch somewhere, but a approx. 10% rise in power from stock seems about right.
#44
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Lart what kind of fuel was he running?
#45
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about 928's I can't say anything I am under a death treat.