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I'm going to replace my 2 fake exhaust's with 2 real ones, is there something more I should do?
I'm not much into Dyno results* (I'll let someone else do that) I'd rather spend the $50 on food or something. From what Thumper and Lakes have said, I'll let my accelerator foot do the dyno testing Martin
I'm not much into Dyno results* (I'll let someone else do that) I'd rather spend the $50 on food or something. From what Thumper and Lakes have said, I'll let my accelerator foot do the dyno testing *I would rather "feel" the results rather than look at them...
Hi guys, interesting thread,Is this a Diesel mod only? Would this work for Petrol engine,I'm going to replace my 2 fake exhaust's with 2 real ones, is there something more I should do?
Guys, pay $50 for a before and after dyno run with the exhaust.....the results MAY surprise you and have had some experience, with things like this and we both noticed a gain. what i think is it makes the same power 7 Torque, BUT.... it makes it quicker ( shorter time 0 than before. i am borred to death looking at dyno graphs these day's, as they all just show rev per minute, i like the way you did the SAE correction as this is the only way to use a dyno as a tool to develop a motor ( thats if that's what you want to do. but RPM on a graph does not tell me much as i have seen guys rev and rev and rev, seemed like forever and the RPM graph just showed KW & TQ @ 1,000 or 2,000 and so on but if i had not have been watching the run i would not have known just how slow that was to rev out. so when i use the dyno to test i only like doing a timed dyno run, and i only look at what i made in 5seconds of wide open throtle, what shows up after 5 second's does not interest me. we might change the tune or the set up on my bikes motor before a race meet ( i hate doing that as i have to learn my set up all over again, makes it harder ) anyway i don't care what makes the most power or Torque, i use the tune that makes the most power & torque the fastest. and when i look at my time ticket i see the gain. if i just go for the tune that show's the biggest numbers and i don't worry about how long it took to make them, i do not always see a gain on my time ticket. in the end the black dyno is what counts.so if i really wanted to test if what Thumper did then i just tried to duplicate, what i would do is just drive down the M2, then the M7 , then take the great western Hwy exit on a wednesday night, and enter a grudge meet, i would have tools and ramps and have the stock systrem on. then i would line up do a pass, then line up again do another pass, i would take great care to shift at same rev both pass's, i would also check the rev i was holding the motor at on the line and also opperate the clutch the same both pass's. then i would study my two time tickets to see how consistant i was. if satified i would put the rear up the ramps and remove the stock rear box bolt on the Thumper system. go out again and duplicate what i had done on ther first two pass's. then i would look at 60Ft time then 330ft time the 660ft time and half track speed, then 1,000ft time then quarter mile time and trap speed, i would also look at my reaction times as if the car launched harder this would show up in a quicker reaction time. if i had gains all the way and a faster half trap speed but the same quarter mile trap speed, this would tell me it made the power and Torque quicker but as the quarter mile speed was the same no more power. also it would be real world tersting as i would have speed and wind resistance.also did you test the air fuel ratio again when you removed parts of the system?i find it very hard to beleave that the diesel could even run @ 30 to 1 AFR.John
Thanks for the replies guys, always good to get some solid technical discussion going in a thread The dyno we use is a Mainline Dynolog twin retarder system that is the most advanced and sensitive chassis dyno that money can buy - and you need plenty of that as its about the same cost as 4 x i30 CRDi SLXs on-road! Repeatability is excellent, and the dyno can even log data (such as boost pressure, rpm, inlet temp etc) straight out of the i30 diagnostic port - which is where the boost curve we printed comes from. I will get some more dyno plots for you today, however the previous testing showed all the different exhaust combinations to draw the identical line one on top of the other, which with our considerable drag racing experience leads us to believe no change in ET or MPH on the strip
