Alex Posted August 8, 2005 Share Posted August 8, 2005 Fair enough....8% is potentially too low...but that means Ian produced even more power. I'd rather guess too low that too high 15% would mean 667BHP.... Quote Link to comment Share on other sites More sharing options...
Guest Terry S Posted August 8, 2005 Share Posted August 8, 2005 not sure the 67 can flow that much mate As Digsy said the peak figure is excellent. Many congrats to Ian, and it shows what a well specced kit and an intelligent man can do Quote Link to comment Share on other sites More sharing options...
Pete Posted August 8, 2005 Share Posted August 8, 2005 That's more like it. Thanks guys. Quote Link to comment Share on other sites More sharing options...
Digsy Posted August 8, 2005 Share Posted August 8, 2005 Fair enough....8% is potentially too low...but that means Ian produced even more power. I'd rather guess too low that too high 15% would mean 667BHP.... 8% is very low for Ian's auto Has anyone got any views on my post above regarding the shape of the torque curve? Quote Link to comment Share on other sites More sharing options...
Guest Terry S Posted August 8, 2005 Share Posted August 8, 2005 8% is very low for Ian's auto Has anyone got any views on my post above regarding the shape of the torque curve? TBH its very rare to see a graph climb like that after 5k but who knows... Quote Link to comment Share on other sites More sharing options...
Ian C Posted August 8, 2005 Author Share Posted August 8, 2005 Rogue - sorry mate, I missed your post. Terry and Alex have pretty much explained it though The wheels figure is good - JB has run my 129mph terminal speed from TOTB4 through a horsepower calculator and it came back with 586bhp, so that's pretty close to my wheels figure! I'd rather the engine was at 626 than 667 to get that RWHP figure because that means it's working a little less hard Sod the pub-brag figures, I'm happy with the 8% figure as it's the most pessimistic result, hopefully then no-one will think I'm bullshitting After looking at a few other dyno charts, it seems that torque curves with turbo cars are different to the NA style curves - the crossover point is much closer to peak power than NA engines. Either that or Digsy is right in saying there is something about rolling roads that skews the torque curve. I've gotta hand it to those cams as well, they definitely make all the difference after about 5500rpm - stockers start to fade there with the mega-conservative lift spec and lower duration. These puppies just keep on going to the redline. We all know that dyno graphs are a bit mystical - I'm happy with this one as it fits in fairly well with other observed results Thanks for all the support and big-ups guys, means a lot to me -Ian Quote Link to comment Share on other sites More sharing options...
Pete Posted August 8, 2005 Share Posted August 8, 2005 Rogue - sorry mate, I missed your post. Terry and Alex have pretty much explained it though No worries - I just like to have my information backed up with some technical understanding of what I'm looking at. If I don't understand something I'll be the first to say "I don't get it!". Only way you'll ever learn. Quote Link to comment Share on other sites More sharing options...
Matt Harwood Posted August 8, 2005 Share Posted August 8, 2005 I've gotta hand it to those cams as well, they definitely make all the difference after about 5500rpm - stockers start to fade there with the mega-conservative lift spec and lower duration. These puppies just keep on going to the redline. Having recently experienced these myself, I have to agree, they really do pull stronger where the stockers fade off... They seem to have an exagerated effect with the single kit, maybe that's because the sequentials are running out of puff at that point. They work even better with a raised rev limit Quote Link to comment Share on other sites More sharing options...
Ian C Posted August 8, 2005 Author Share Posted August 8, 2005 They work even better with a raised rev limit For a while Until that noise starts :eek2: Quote Link to comment Share on other sites More sharing options...
Matt Harwood Posted August 8, 2005 Share Posted August 8, 2005 That's what det cans are for Quote Link to comment Share on other sites More sharing options...
eyefi Posted August 9, 2005 Share Posted August 9, 2005 nice one ian, it's good to see you coming to a conclusion (yeah right ). did you do any of your mapping (ign or fuel) on a dyno? Quote Link to comment Share on other sites More sharing options...
eyefi Posted August 9, 2005 Share Posted August 9, 2005 i've enclosed a clearer dyno (i can't read them when they have dual y axis values). do you have the datalog for the run or the boost log? Quote Link to comment Share on other sites More sharing options...
Ian C Posted August 9, 2005 Author Share Posted August 9, 2005 That's what det cans are for What, listening to your broken rod flail around? -Ian Quote Link to comment Share on other sites More sharing options...
Ian C Posted August 9, 2005 Author Share Posted August 9, 2005 i've enclosed a clearer dyno (i can't read them when they have dual y axis values). do you have the datalog for the run or the boost log? Nice one - the graph should have been in colour but it all stopped working properly the moment I got near, no change there then I didn't datalog it or anything, I just wanted to get it done. What you see is what I've got although I have got a WOT-in-5th graph showing afrs and boost pressure somewhere, generated from a TOTB-shakedown datalog. That's at home though, if I remember I'll post it up for you I didn't do any mapping on a dyno - all road mapped, took my time over it. -Ian Quote Link to comment Share on other sites More sharing options...
Ian C Posted August 9, 2005 Author Share Posted August 9, 2005 Er, actually, I think you've got the curves the wrong way around Quote Link to comment Share on other sites More sharing options...
eyefi Posted August 9, 2005 Share Posted August 9, 2005 Er, actually, I think you've got the curves the wrong way around are you sure? 450 ft/ib @ 7000 rpm / 5252 = 600hp Quote Link to comment Share on other sites More sharing options...
Digsy Posted August 9, 2005 Share Posted August 9, 2005 are you sure? 450 ft/ib @ 7000 rpm / 5252 = 600hpIt does indeed Right - I've ben talking to my turbocharging mate about the shape of that torque curve. It's all good. It's not the dyno distorting the shape of the curve, its a combination of the size of the turbo and the length of the intake runners. Apparently (and I'm paraphrasing a bit here so forgive me if I skip the fine details) because the turbo is so fecking enormous, it gives the intake system some appreciable exhaust backpressure to work against, and enhances the effects of any intake tuning that might be going on. When the engine is on song, maximum boost, wastegate open, steady state, its effectively acting like a big NA engine. Because the 2JZ's intake runners are so short, you can expect to see some peaking at the top end. In fact, looking at the chart, I expect you were actually on peak boost at 5000, and then you got a tuning spike at 6300. if you remove the tuning spike, you get a torque curve that matches the boost curve. So there you go. I love it when a plan comes together. Quote Link to comment Share on other sites More sharing options...
Guest Terry S Posted August 9, 2005 Share Posted August 9, 2005 The turbo isn't huge at all mate, trust me Quote Link to comment Share on other sites More sharing options...
DamanC Posted August 9, 2005 Share Posted August 9, 2005 awesome Quote Link to comment Share on other sites More sharing options...
Ian C Posted August 9, 2005 Author Share Posted August 9, 2005 are you sure? 450 ft/ib @ 7000 rpm / 5252 = 600hp The thick lines are the torque ones and the thin ones are the power ones, I think your graph has the thick one as the power curve? Dunno, it's hard to tell... Thanks Digsy, so you are saying a bigger intake plenum would give me loads more power? windups aside, you mean the flat bit at 5500rpm isn't really a 'mapping' flat bit, but it's where some intake tuning takes effect and maybe the cams kick in? -Ian Quote Link to comment Share on other sites More sharing options...
Digsy Posted August 9, 2005 Share Posted August 9, 2005 Thanks Digsy, so you are saying a bigger intake plenum would give me loads more power? windups aside, you mean the flat bit at 5500rpm isn't really a 'mapping' flat bit, but it's where some intake tuning takes effect and maybe the cams kick in? -IanGrrrr Ah - yes, that reminds me. He specifically asked me if you had big cams or not. The way I understand it is that if you didn't have the tuning effects, your curves would look like the dotted lines, which ties up with how I expected them to look, based on the shape of your boost curve. Quote Link to comment Share on other sites More sharing options...
Ian C Posted August 9, 2005 Author Share Posted August 9, 2005 Who needs VVTi eh? -Ian Quote Link to comment Share on other sites More sharing options...
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