Dyno Day..what a joke!
05-19-2008, 07:44 PM
#1
Dyno Day..what a joke! So you can see from my signature for the most part what modifications I have done..Full bolt on, gears, custom 4l60e blah blah blah..So I had a dyno today on a Dynojet machine..255rwh and 288rwtq..
I'm a little confused at these numbers..
I'm trying to understand how it is I have raced and beaten plenty of similar cars with over 300rwh yet my numbers are in the 200's. Some of these cars I raced I think it's fair to say...I smoked the shi* out of them!
Today WAS a really warm and muggy day..could this play part? The guy told me that my car was running really lean and in his opinion, unsafe to drive for the engine and with it running so lean and I was losing out on anywhere from 50-60rwh. Funny thing is, I just had the car hooked up to a scanner by a reputable shop I get most of my work done at A week ago and everything was looking AWESOME..wasn't running lean etc etc..
I have seen numbers from guys on here with pretty much my same set up with a lot more miles on theirs and they all were in the 300+ range..I just don't see my number holding true. Ya think his machine was maybe garbage? Who knows...but
on my numbers today.
I'm a little confused at these numbers.. I'm trying to understand how it is I have raced and beaten plenty of similar cars with over 300rwh yet my numbers are in the 200's. Some of these cars I raced I think it's fair to say...I smoked the shi* out of them! Today WAS a really warm and muggy day..could this play part? The guy told me that my car was running really lean and in his opinion, unsafe to drive for the engine and with it running so lean and I was losing out on anywhere from 50-60rwh. Funny thing is, I just had the car hooked up to a scanner by a reputable shop I get most of my work done at A week ago and everything was looking AWESOME..wasn't running lean etc etc..
I have seen numbers from guys on here with pretty much my same set up with a lot more miles on theirs and they all were in the 300+ range..I just don't see my number holding true. Ya think his machine was maybe garbage? Who knows...but
on my numbers today. 
05-19-2008, 08:04 PM
#2
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You now have a baseline, that’s all this is! HP doesn’t just happen you have to work and tweak a car or everyone would have a fast car. This is real world, NOT unusual!
Street racing has many variables, at least you have some kills. The dyno is offering an opportunity to improve.
How lean? Take him serious his wideband should be accurate.
I have seen MANY scanners give an LT1 clean bill of health. I will say again buy a cable get Datamaster.
You paid for data, he found you are lean look on bright side you now know you need to fix it. You could have melted engine not knowing. Roll up sleeves and move ahead!
Good luck
Good luck
05-19-2008, 08:04 PM
#3
WOT is a different air fuel strategy than cruising and narrow band o2's are not reliable under max power air fuel ratios. If he had a wideband hooked up maybe you are running lean and should look into it. Your numbers dont match your mods in the least. You either need to correct your tune, or make sure your fuel pressure isnt dropping off under wot. Thats my suggestion rather than bashing the dyno right off the bat and assuming everything is fine because it was last week.
What kind of air/fuel ratios were you showing on the dyno?
What kind of air/fuel ratios were you showing on the dyno?
05-19-2008, 08:13 PM
#4
Battleship, the Datamaster..what is this?? Never heard of it. Ya, poop numbers IMO. Oh well, don't really know what else to say but I wish they had been better. All I know is I'm gonna have a lot more guys wanna run me when I tell them these numbers..lol.
05-19-2008, 08:40 PM
#5
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Your numbers are probably not that far off. What do you consider "Full bolt ons"? By your sig. it looks like you have mostly suspension mods and not many HP mods. The power you are making is being put to the ground well, that is why you are still able to kill people on the street.
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05-19-2008, 08:58 PM
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Your numbers are probably not that far off. What do you consider "Full bolt ons"? By your sig. it looks like you have mostly suspension mods and not many HP mods. The power you are making is being put to the ground well, that is why you are still able to kill people on the street.
05-19-2008, 09:07 PM
#9
You didn't say if your races were on the street or on the track, but your auto trans could be helping you out a lot if the higher HP guys can't drive well enough to get the most out of their manual cars.
That's a ridiculous statement. 1. Your motor will make MORE power when it is leaner than when it is too rich. 2. In a 250 RWHP combo, you are NOT leaving that much power on the table. There is not that much power to be had merely by tweaking the fuel curves... unless the car was so rich it couldn't run at all. 
That statment leads me to mistrust the overall knowledge and judgement of your dyno guy.
Leaner is going to make it run hotter and also make it detonation prone. Get to someone with a wideband who knows what the fock they are doing and see where your A/F really is.
That statment leads me to mistrust the overall knowledge and judgement of your dyno guy.
Leaner is going to make it run hotter and also make it detonation prone. Get to someone with a wideband who knows what the fock they are doing and see where your A/F really is.
05-19-2008, 09:19 PM
#10
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I'm not an expert but, that does sound a little low. When I was on the first motor with some bolt-ons (exhaust, Intake, ignition) my dyno numbers were like 282/319. Its a manual so a little less loss there for me. Umm... Anybody else have bad things to say about the dyno you went to? Definitely check into the possibilty of an A/F issue. If you dont feel that you had an accurate dyno session just try someone elses shop....
05-19-2008, 09:22 PM
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You can read about Datamaster here
http://www.ttspowersystems.com/DataMaster.html
Below is a screen capture of a boosted LT1 running through the rev limiter...I always here how LT1's do not like high RPMs but they do run higher than most say. You can see there is a DTC code '11' which is the engine bulb fault. Not useful but GM couldn't get it all right.
As you should see there is alot of data. This is high RPM shot and since it has shot through rev limiter the fueling is starting to show lean in the right bank because the injectors are shutting down and the timing has been reduced by 10 degrees because of knock. This motor was running 12 psi and has 60 lb injectors with 60 psi fuel pressure.
EDIT I just saw the date is from Nov 2005 so I think this is 8 psi boost. Can't tell since the MAF max'd out for this tune where it is at. But I didn't run higher boost until 2006 so it is probably initial setup
http://www.ttspowersystems.com/DataMaster.html
Below is a screen capture of a boosted LT1 running through the rev limiter...I always here how LT1's do not like high RPMs but they do run higher than most say. You can see there is a DTC code '11' which is the engine bulb fault. Not useful but GM couldn't get it all right.
As you should see there is alot of data. This is high RPM shot and since it has shot through rev limiter the fueling is starting to show lean in the right bank because the injectors are shutting down and the timing has been reduced by 10 degrees because of knock. This motor was running 12 psi and has 60 lb injectors with 60 psi fuel pressure.
EDIT I just saw the date is from Nov 2005 so I think this is 8 psi boost. Can't tell since the MAF max'd out for this tune where it is at. But I didn't run higher boost until 2006 so it is probably initial setup
Last edited by BattleShip; 05-19-2008 at 09:27 PM.
05-19-2008, 10:15 PM
#13
You didn't say if your races were on the street or on the track, but your auto trans could be helping you out a lot if the higher HP guys can't drive well enough to get the most out of their manual cars.
That's a ridiculous statement. 1. Your motor will make MORE power when it is leaner than when it is too rich. 2. In a 250 RWHP combo, you are NOT leaving that much power on the table. There is not that much power to be had merely by tweaking the fuel curves... unless the car was so rich it couldn't run at all.
That statment leads me to mistrust the overall knowledge and judgement of your dyno guy.
Leaner is going to make it run hotter and also make it detonation prone. Get to someone with a wideband who knows what the fock they are doing and see where your A/F really is.
That's a ridiculous statement. 1. Your motor will make MORE power when it is leaner than when it is too rich. 2. In a 250 RWHP combo, you are NOT leaving that much power on the table. There is not that much power to be had merely by tweaking the fuel curves... unless the car was so rich it couldn't run at all.
That statment leads me to mistrust the overall knowledge and judgement of your dyno guy.
Leaner is going to make it run hotter and also make it detonation prone. Get to someone with a wideband who knows what the fock they are doing and see where your A/F really is.
Not gonna mention names but the guy who did my dyno is a well known pric* in my area. I went there because I was told that type of Dyno machine was one of the best..plus it was really close to home. But I agree about his statement.. he didn't have kind words for my tuner after we were finishing up..I STOOD my ground on that one.
No cam yet..As far as racing goes..all street. Have not tracked it.
I was really hoping to hit the 280 mark. Didn't happen so I guess we go from here. I will be checking out this whole running lean issue.
05-19-2008, 10:17 PM
#14
sounds dead on for ur mods everyonethinks they have more than they do untill they hit the dyno i hit 258rw with a fullbolton a4 lt1.boltons arent good for much maybe 30hp its realy just prepwork for a cam.
05-19-2008, 10:53 PM
#16
**** all that **** dude, I dont trust that guy as far as I can spit. You know your car is making way more power than that! Sorry no matter what these guys say those #s are WEAK and if these other guys are makin that with bolt ons thats there problem they got a slug
So I have way more mods than this guy does that mean it would be normal to dyno 75hp less I dont think so!!!!!!
http://videos.streetfire.net/video/1...Z28_110973.htm
So I have way more mods than this guy does that mean it would be normal to dyno 75hp less I dont think so!!!!!!
http://videos.streetfire.net/video/1...Z28_110973.htm
05-20-2008, 03:42 AM
#19
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from what ive seen autos dyno lower than m6's that run the same times. what kind of dyno was it? ive heard it has something to do with the converter. do you have a good converter ?
