dukenukem Posted June 19, 2009 Share Posted June 19, 2009 (edited) Put my 1996 J-Spec TT on the Dyno last weekend and scored a slightly disappointing 266 BHP . The car has done 60k miles and is in good condition apart from the fact the turbos are running at 0.6 bar and should be 0.9. The car is completely stock, standard intake box, exhaust etc. nothing's been tweaked. Is this just age? Any suggestions? Boost Pressure.pdfPower.pdf Edited June 19, 2009 by dukenukem (see edit history) Quote Link to comment Share on other sites More sharing options...
j80leo Posted June 19, 2009 Share Posted June 19, 2009 Try giving the car a good service, normally helps alot. Quote Link to comment Share on other sites More sharing options...
Mcgoo Posted June 19, 2009 Share Posted June 19, 2009 If thats at the wheels, thats about right isn't it? Quote Link to comment Share on other sites More sharing options...
mikeyb10supra Posted June 19, 2009 Share Posted June 19, 2009 why is it dissapointing? Your not even running stock boost so the figure is about right I say Quote Link to comment Share on other sites More sharing options...
magictorch Posted June 19, 2009 Share Posted June 19, 2009 As above give the car a good service and then go bpu, that will get your power up and a smile on your face;) Quote Link to comment Share on other sites More sharing options...
tooquicktostop Posted June 19, 2009 Share Posted June 19, 2009 That graph seems very smooth for a twin turbo graph, it looks like the 2nd turbo is not coming on line hence the low boost and the lower BHP figure ? Quote Link to comment Share on other sites More sharing options...
Matt H Posted June 19, 2009 Share Posted June 19, 2009 That graph seems very smooth for a twin turbo graph, it looks like the 2nd turbo is not coming on line hence the low boost and the lower BHP figure ? I was going to say that. It doesn’t look like there is any transition to second turbo. Usually, you get an ever so slight plateau as the second turbo joins in on stock. Isn't 0.6 bar what you get off the first and 0.9 what you get when the second comes in? Quote Link to comment Share on other sites More sharing options...
dukenukem Posted June 19, 2009 Author Share Posted June 19, 2009 If thats at the wheels, thats about right isn't it? It's 219 at the wheels (other graph), 266 at the flywheel. Quote Link to comment Share on other sites More sharing options...
dukenukem Posted June 19, 2009 Author Share Posted June 19, 2009 (edited) I was going to say that. It doesn’t look like there is any transition to second turbo. Usually, you get an ever so slight plateau as the second turbo joins in on stock. Isn't 0.6 bar what you get off the first and 0.9 what you get when the second comes in? The 2nd turbo definately works, get the boost at 4000rpm. Having researched further, according to Homer's BPU explanation the stock TT produces 0.76bar, not 0.9. I was wandering where my 0.3 went, but maybe its only 0.16 thats gone walkies. Noticed there's a few dead flies in the air filter. New one of them might help, and generally a proper good service. Cheers for the input. Edited June 19, 2009 by dukenukem (see edit history) Quote Link to comment Share on other sites More sharing options...
Matt H Posted June 19, 2009 Share Posted June 19, 2009 (edited) The 2nd turbo definately works, get the boost at 4000rpm. In that case, something isn't working quite properly or your engine hasn't be maintained properly. As said, the first port of call is to change or your servicables. See what happends from there. J-specs should be over 300 in stock form if everything has been maintained properly so you've got quite a reasonable deficit in power. Supra's aren't know for loosing much power over age. Edited June 19, 2009 by Matt H (see edit history) Quote Link to comment Share on other sites More sharing options...
hadyn Posted June 19, 2009 Share Posted June 19, 2009 Check your turbo/intercooler pipework and then the condition of the intercooler itself. Then check all the VSVs to see if they're working OK too Quote Link to comment Share on other sites More sharing options...
dukenukem Posted June 19, 2009 Author Share Posted June 19, 2009 In that case, something isn't working quite properly or your engine hasn't be maintained properly. As said, the first port of call is to change or your servicables. See what happends from there. J-specs should be over 300 in stock form if everything has been maintained properly so you've got quite a reasonable deficit in power. Supra's aren't know for loosing much power over age. The engines in good condition, scored 266 BHP with low boost. I blame the Turbo's. At the right pressure I would have hoped for 280 or more, and with a good service closer to 300, but yeah need to get it looked at. Quote Link to comment Share on other sites More sharing options...
paul_h Posted June 19, 2009 Share Posted June 19, 2009 probably just a boost leak somewhere get it leak tested Quote Link to comment Share on other sites More sharing options...
gsportcars Posted June 19, 2009 Share Posted June 19, 2009 Could be any number of things. Is it holding a steady 0.6bar or is it inconsistent? Boost leak, sticky actuator/s, vsv's etc. Just get a good look around it and trace all pipes, vacuum lines etc etc. Quote Link to comment Share on other sites More sharing options...
mikeyb10supra Posted June 20, 2009 Share Posted June 20, 2009 depending on the condition of the SMIC, I would put my cash on that Quote Link to comment Share on other sites More sharing options...
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