Need a TUNER!!!
http://www.hptuners.com/forum/forumdisplay.php?f=23
Last edited by WS6FirebirdTA00; Jul 4, 2008 at 08:15 PM.
)Your dyno uses a lighter weight drum. Weight has nothing to do with it like most people think. A 3600 lb roller does not load the car the same as a 3600 lb on the street. Using calculations to determine the load on the car from the drums inertia, it would be like tuning the car on the street but with approximately 700 lbs less weight. I have been meaning to put the calculations in to a word or MathCad file, if I do I will post it up.
Less weight equals less load.
Less load equals a leaner burning mixture.
Leaner mixture can make less power and most certainly will with knock (seen in Jason's dyno graph at the sudden dip). I can post the logs from the street that show rock solid fueling with no knock (and more sensitive knock sensor settings than the previous tune had).
I helped STREET (where the car is actually driven) tune Jason's car. Timing and fueling was setup for street conditions.
Please refer to this post for even more details:
http://www.musclecar-evolution.com/f...8&postcount=30
As you can see, I have two tunes I use for my car. There is a street tune and a dyno tune. I have to make adjustments for the dyno load on my car to bring my fueling back in line to where I command. I can see a 12 hp swing easy on my car from the street to the dyno. Please refer to the attachment for this difference. Also, my 7.17 pass was a hot lap, 2nd pass right off the street. My dyno tune passes are several tenths slower than that (tried it for the hell of it once). Same thing happened in my buddy's Z06.
Leaving power aside, getting a car to properly idle and run when driven on the street is the biggest part of a tune.
Jason, when you come up at the end of this month we will put your old tune back in the car and then I will "dyno tune" your car and we can post up the results from the comparison. I have a local shop I go to for my dyno use.
Jason's tune is fine. I have no doubt (based on all the data I posted) that his car will gain power on the dyno. I don't care if it gained 20 hp on the dyno, the street tune will be faster at the track very easily.
Last edited by WS6FirebirdTA00; Jul 4, 2008 at 09:08 PM.
The Best V8 Stories One Small Block at Time
Um, sorry... but Will and ingenious don't go in the same sentence.
I'm just hoping that Will says something to **** Mike off... because then we'll all get to see how hacked up my tune was... and Hunters!
So PLEASE say something stupid Will... cause you haven't let us down thus far.
And Chris, if you'd like to say something stupid (and you certainly haven't let us down yet either) feel free!
I'm just hoping that Will says something to **** Mike off... because then we'll all get to see how hacked up my tune was... and Hunters!
So PLEASE say something stupid Will... cause you haven't let us down thus far.
And Chris, if you'd like to say something stupid (and you certainly haven't let us down yet either) feel free!
Jason, I already told to post the tune!!! I would love to see it again!
Please, by all means post it! I say alot of stupid ****, it's the internet!!!
But I don't do stupid ****, like street race on 285 and then rearend the car infront of you doing 130mph in which puts you into a spin and scares the **** out of your wife in the passenger seat! Now that's STUPID!!!
)Your dyno uses a lighter weight drum. Weight has nothing to do with it like most people think. A 3600 lb roller does not load the car the same as a 3600 lb on the street. Using calculations to determine the load on the car from the drums inertia, it would be like tuning the car on the street but with approximately 700 lbs less weight. I have been meaning to put the calculations in to a word or MathCad file, if I do I will post it up.
Less weight equals less load.
Less load equals a leaner burning mixture.
Leaner mixture can make less power and most certainly will with knock (seen in Jason's dyno graph at the sudden dip). I can post the logs from the street that show rock solid fueling with no knock (and more sensitive knock sensor settings than the previous tune had).
I helped STREET (where the car is actually driven) tune Jason's car. Timing and fueling was setup for street conditions.
Please refer to this post for even more details:
http://www.musclecar-evolution.com/f...8&postcount=30
As you can see, I have two tunes I use for my car. There is a street tune and a dyno tune. I have to make adjustments for the dyno load on my car to bring my fueling back in line to where I command. I can see a 12 hp swing easy on my car from the street to the dyno. Please refer to the attachment for this difference. Also, my 7.17 pass was a hot lap, 2nd pass right off the street. My dyno tune passes are several tenths slower than that (tried it for the hell of it once). Same thing happened in my buddy's Z06.
Leaving power aside, getting a car to properly idle and run when driven on the street is the biggest part of a tune.
Jason, when you come up at the end of this month we will put your old tune back in the car and then I will "dyno tune" your car and we can post up the results from the comparison. I have a local shop I go to for my dyno use.
Jason's tune is fine. I have no doubt (based on all the data I posted) that his car will gain power on the dyno. I don't care if it gained 20 hp on the dyno, the street tune will be faster at the track very easily.
Actually Mike, Jason's last dyno pull did make less HP on the dyno, but i will tell you it pulled hard as hell on the street!
Although this graph is hard to see, at 4800ish RPM is where you can see it picked up knock. However, you can see in the low end where it actually picked up power. On every car I tune, if I get a chance to make fueling corrections for the dyno load, I will gain power all across the board. I was quite surprised that the power of the street tune matched the last tune that was in the car. I would have expected it to be lower all across because that tune was "optimized" (according to the previous tuner) on the dyno. This is why I don't really get caught up in dyno numbers, but if you are not making track passes, that is all you really have.
The problem is there is a LOT of uneducated people on the internet that would see the car lost power and immediately think the tune was crap. In a way, yes it is crap, but for dyno conditions. You know what this means though? Dyno tunes are crap on the street. Competent tuners will make street passes to ensure their work. More people need to understand the truth and what they are getting (or lack of getting) for their money. Yes, there are many Competent shops out there that do some good jobs on tunes. Honestly, there are very few that will put a wideband in the exhaust and check the real fueling on the street. I am very meticulous about my tunes and treat them all as my car. Each one leaves with a tuned Primary VE, Secondary VE (98-00 cars with the stock OS), and MAF tables. Most of the time the VE tables do not get touched. Do you know what tables are used if the MAF fails? VE. What happens if the MAF fails at WOT and the VE table is stock and does not have enough fueling? I know some comments have been made about Jason's tune on "why it hasn't blow up yet" and how I "always tune cars lean". Will needs not make comments like this. If you honestly want me to post the reasons why, I would not mind showing people how things are done. Any dyno pull on a dyno with less load will be lean. Most dynos also take readings out of the tail pipe which could make the readings 0.5-1.0 points leaner than it really is.
Clearly all my street tunes will read lean on a lighter dyno because it is a lot less load. Run it on a dynojet 248 and it will be the other extreme, too rich. Jason's car won't blow up because the fueling is actually in the 12's on the street to keep it safe opposed to the lean conditions that were previously in it, approaching 14.0:1 (!!!) on the street. I could lean it out even more, still safely, without issue. This is the part where the uneducated shop owners start to make comments about things they have no idea on and at this point I do not care to share any more information to help educate them. People should not make comments about safe tunes when they really have no idea what safe is (or the fact that they have several cars out there with much higher power running tunes so ridiculously hacked it is amazing issues have not arose yet).
The bad part is when you can tell a difference in two tunes just by SOTP difference on the street. That is more certainly more than a 10-15 hp difference if you can feel it.
Last edited by WS6FirebirdTA00; Jul 5, 2008 at 06:30 AM.
In one of Will's posts he typed pretty much what I suggested to his partner over the phone regarding time, $$ and effort for street tunes. IMHO, shops should educate (especially the less traveled ones) customers on what a dyno tune for $500 - $650 really is. Then give the customer an option to pay more for street tuning or buy your own **** and log/tune, log/tune, log/tune it yourself.
Jerry said it way back in the thread, any moron can tune for WOT on a dyno. Two pulls @ WOT for $550 and claiming your car's tuned is friggin' BULLSHIT!

I can give my sister the editor, tell her to change PE (commanded fuel) to get the actual fueling right at WOT (please, no one do this as it is not right) and if any knock shows up once the target fueling is reached, back off the main spark tables. It is that easy to put up a decent dyno number to make people think they have a good thing. Honestly that is what a lot of (not all) shop tuners do, mainly the ones in discussion in this thread.
People don't realize what crap they have until they actually drive around with a real tune in the car
I am not trying to burn anyone here as I have nothing to gain from it. I do tunes when people need them and don't care to advertise, I don't need the business. I have a full time job, tuning is just fun for me. That is why it didn't really bother me when you and Will both bailed on coming up here. Will was suppose to stop on his way through, never called and then I guess you just decided to go with a different system so you did not come. It is aggravating giving advice then seeing Will run his mouth. I could see if I was being a dick but I told no one I spoke with him on the phone. Jason and Chris can both speak to that. I will just know in the future how to handle this.
It would be nice to see the real potential out of some of these cars though and I would hate to see anyone's car lose a motor due to an improper tune.
Last edited by WS6FirebirdTA00; Jul 5, 2008 at 11:02 AM.

I can give my sister the editor, tell her to change PE (commanded fuel) to get the actual fueling right at WOT (please, no one do this as it is not right) and if any knock shows up once the target fueling is reached, back off the main spark tables. It is that easy to put up a decent dyno number to make people think they have a good thing. Honestly that is what a lot of (not all) shop tuners do, mainly the ones in discussion in this thread.
People don't realize what crap they have until they actually drive around with a real tune in the car







....especially the no conscience part.