I got some mods done to my car and I'm not happy at all the dyno results. I haven't gotten it tuned yet but it should be this bad.

It's a 98 Camaro Z28 A4

Here's what I have done so far .. K&N Air filter with ram air hood, 3.73 gears, headers, ory, dynomax bullet, slp underdrive pulley, b&m trans cooler, 160 thermostat.

I've got heads, cam, intake, new tb, tci torque converter, tranny rebuild kit and lost more for the next stage (when I save up more money).

I just can't believe that I peaked at 298.03 rwhp and 311.37 torque. Maybe I just don't get it. Please help me understand. My brothers car is a 99 TransAm M6 and with only ram air and cat back he put down 320 rwhp and 335 torque. I'll scan his graph after I see him.


It's hard to read but at the bottom of the page there is says:
RunFile_002.drf - 11/3/2006 2:11:56 PM Run Type: RO Run Conditions: 67.18 F, 29.78 in-Hg, Humidity: 10%, SAE: 0.97
Max Power = 298.03 Max Torque = 311.37

 

for most of the cars i have or seen dynoed the auto cars are normally right around that area. the manual cars normally put out around 310-325 hp stock or with normal bolt ons. the auto cars are normally around 270-310 at best. with the mods performed you should be slightly higher but i don't know by how much. k&n filter kits are great kit but do not put the numbers they claim by what i have seen. beware of the added 20hp claims. alot of them don't mention that it was at 2500 rpm. the mods you have done are best tested on the track and not always on the dyno. you did not mention any computer programming which normally makes the most power. i would recommend a good tuner using ls1edit or live for your future mods. a good tuner will make the smile meter go through the roof

 

Okay that makes me feel a little better that it's because it's an auto. He did tell me that I'd lose about 5% for the auto. Once I have the heads, cam and tranny done he's going to tune it for me. I think he uses HP Tuner. He said it wasn't worth doing until after I do the other stuff.

 

Also .. what does the vertical line signify? I'm talking about the one in the middle of the graph where it shows 270.97 hp and 310.58 torque.

 

That's just where the cursor was resting (4,582rpm) when they plotted the graph.

It seems to nose over a bit at about 5,200rpm, losing torque steeply and causing the HP to tail off. Is that typical for the LS1?

 

I don't think it's typical because my brothers graph just keeps going up and up. The guy at New Era Performance thinks my tranny is tired (no big deal, I planned on rebuilding it anyway) and that I may have valvetrain issues (also not big deal, am changing heads, cam and everything up top anyway). He said that's why it's wavy and falls off instead of rising smoothly. I just take his word for it so that's why I wanted input from the people here. Makes it easier to swallow when there is multiple people agreeing on the same thing.

 

They've got the "smoothing" set to 5, which covers up the "waves".

Also, check your buddy's plot.... yours is "SAE" corrected. If his is "STD" corrected, it will show slightly higher results.

 

the transmission is engaged and should not effect the upper portion of the graph unless it is slipping, depending on how many miles you have the valve springs could be getting weak. the correction std or sae and the smoothing effect will make a couple horsepower differences. most dyno shops will use the one that has the highest reading

 

I'll check his graph to see what his is set to. My car has 53k miles on it.