Dynoed Yesterday
Dynoed Yesterday
well i finally got my car dynoed and i'm not sure i'm happy with the results without the cattman y-pipe but with the jwt pop charger and my own custom b-pipe as well as the cattman muffler i put down 210hp and 221tq now with the y installed i put down 212hp and 218tq this was on 2 different dyno both were dynojets and my car is an auto is this low for my mods?
Originally Posted by MaximaSe2002
there was another guy there with stock se 6 speed put down 201hp...but the thing that gets me is that with the y i gained 2 horse and losses tq
If I'm reading it correctly the runs were done on different dyno's so that make the comparison a little more difficult.
I would say that your numbers are pretty good. I'm an auto w/ FC intake and Cattman Y and I'm only getting 206hp/216tq.
Should I expect those numbers if I get a catback then or is my car just different?
Should I expect those numbers if I get a catback then or is my car just different?
both dyno's were sae and the b-pipe is 2.5in outside diameter...i'm still running the stock cat...i'll try to find the first graph and post them tomorrow although i don't have a scanner i'll try to get to my parents house and use theirs
Originally Posted by MaximaSe2002
there was another guy there with stock se 6 speed put down 201hp...but the thing that gets me is that with the y i gained 2 horse and losses tq
There's nothing precise about dyno runs, especially between different machines and different correction factors (these things aren't consistent, because the SAE corrections cannot take into account the extent that a given model's ECU is compensating for changes in temperature or atmospheric pressure). The dyno applies the same corrections, whether the car has a carburator and no ability to compensate for these variables, or ECU-driven FI that is programmed to accomodate changes in altitude, temperature, etc.
So, I won't quibble with your results except to say that the figures you're quoting - max hp and tq - don't really tell you much. Difference in peaks tells you almost nothing, its the margin of the after run over the before run, across the rpm band, that matters. Tell me what the average hp and tq difference was between 3500 and 6500 rpm - those are useful numbers. For example, if peak numbers showed zero change, but the performance part holds a 15-20hp advantage over the stock part out to redline, it would be a success but someone else would say, "hey, its worthless, look at the peaks."
How do you get those numbers? Always tell them you'll need the tabular data from the run (columns of #s) before you get started. That way, if they're totally clueless about generating anything but a simplistic graph, you can go on to a dyno shop that knows what they're doing. Once you have the #s, pour them into Excel and do some basic spreadsheet analysis to get a real thorough understanding of the results.
I'll also add that the 02/03 Cattman y-pipe has been dyno tested extensively, not only the independent testing that we had done on the prototype, but by several customers. Their "peaks" are significantly higher than your results, but most importantly, the tests show large and consistent power margins over the stock part - low to high rpm, across the board.
Brian C Catts
Cattman Performance
Originally Posted by bgates1654
Hey Brian, could you point me in the right direction to find the independant dynos you speak of? I have been considering your y-pipe for a while but havent seen any good reliable data to solidify my choice.
Sure, no need for a lack of data to hold you back. Send me email and I'll be glad to reply with dyno spreadsheets and graphs later today (I've got some errands to run first).
Brian C Catts
Cattman Performance
ok here is my dyno sheet don't know if you can read it cause i took a picture of it but here it is
http://photos.yahoo.com/serspecv2002
http://photos.yahoo.com/serspecv2002
STD is a correction factor like SAE. STD is a bit more generous than SAE is. For example I recently dynoed at:
227.4whp 243.3wtq STD
When converted into SAE via dynojet's runviewer it returned:
223.0whp/237.2wtq SAE
Well to tell you the truth even if you posted the two dynos and they were legible you couldnt really compare them anyway. Using two different dynos makes it pretty much incomparable. If you really want to know what gains you got with the y-pipe go back to the dyno that you got the baseline from and do it again.
227.4whp 243.3wtq STD
When converted into SAE via dynojet's runviewer it returned:
223.0whp/237.2wtq SAE
Well to tell you the truth even if you posted the two dynos and they were legible you couldnt really compare them anyway. Using two different dynos makes it pretty much incomparable. If you really want to know what gains you got with the y-pipe go back to the dyno that you got the baseline from and do it again.
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