Back from the dyno.............AIR/FUEL ratio NFG.

CSXT802

Enthusiast
Joined
Jul 20, 2010
Posts
418
Reaction score
0
Location
Bushkill PA
Well I cracked 400 WHP not by much. Torque curve is all over the place. Air / fuel is pig rich. There is alot being left on the table with this crappy cal. I was more impressed with my co workers almost bone stock 2010 Camaro SS (6 speed) making 372 WHP / 370 + ft lbs.
 

Attachments

  • scan0001.jpg
    scan0001.jpg
    92.6 KB · Views: 88

speedracervr4

Enthusiast
Joined
Dec 9, 2006
Posts
1,348
Reaction score
0
Location
Lancaster, PA
When was the last time you changed your o2 sensors? Older sensors with carbon build up will cause rich conditions. Easy/cheap things to change that might help the A/F.
 
OP
OP
CSXT802

CSXT802

Enthusiast
Joined
Jul 20, 2010
Posts
418
Reaction score
0
Location
Bushkill PA
When was the last time you changed your o2 sensors? Older sensors with carbon build up will cause rich conditions. Easy/cheap things to change that might help the A/F.
I don't think the o2's play a big role at wide open throttle. I could be wrong. Car has 9000 miles on it. don't think the o2 would be shot.
 
OP
OP
CSXT802

CSXT802

Enthusiast
Joined
Jul 20, 2010
Posts
418
Reaction score
0
Location
Bushkill PA
Well the first mod will be an sct tune to clean up the fueling. low 11's air/fuel is good for boost not an NA motor. The shop owner where i dynoed the car tunes for 13:1 on an NA motor. Right now it"s so rich it could take a 50-75 hp dry shot of NOS and still be safe.
 

DrumrBoy

Enthusiast
Joined
Jul 21, 2003
Posts
2,612
Reaction score
0
Location
GA
That is an interesting (not in a good way) TQ curve. What cam is in it?
 

DrumrBoy

Enthusiast
Joined
Jul 21, 2003
Posts
2,612
Reaction score
0
Location
GA
That is an interesting (not in a good way) TQ curve. What cam is in it?


BTW, not meaning to dis your cam, its actually not bad, just weird that it seems to take a gulp of air or something at 4000 rpm.
 
OP
OP
CSXT802

CSXT802

Enthusiast
Joined
Jul 20, 2010
Posts
418
Reaction score
0
Location
Bushkill PA
BTW, not meaning to dis your cam, its actually not bad, just weird that it seems to take a gulp of air or something at 4000 rpm.

Stock cream puff cam. Looks more like a big gulp of fuel. That's right when the A/F goes into the low 11's
 

DrumrBoy

Enthusiast
Joined
Jul 21, 2003
Posts
2,612
Reaction score
0
Location
GA
That seems wrong for a stock cam. Maybe you have some tired valvesprings or something preventing it from grabbing air at that frequency. I had a similar pattern on a motor before I had it redone...... but it was a strange cam and I attributed the flat mid-curve to the weird cam. That ain't your problem, so if it isn't springs, I'm out of ideas.
 

DrumrBoy

Enthusiast
Joined
Jul 21, 2003
Posts
2,612
Reaction score
0
Location
GA
FWIW, both torque curves take a pause between 3500 and 4500 (or thereabouts) but these are with unusual cams.

NA_Build_Dyno_Sheet.jpg
 
OP
OP
CSXT802

CSXT802

Enthusiast
Joined
Jul 20, 2010
Posts
418
Reaction score
0
Location
Bushkill PA
That seems wrong for a stock cam. Maybe you have some tired valvesprings or something preventing it from grabbing air at that frequency. I had a similar pattern on a motor before I had it redone...... but it was a strange cam and I attributed the flat mid-curve to the weird cam. That ain't your problem, so if it isn't springs, I'm out of ideas.

I see what you are saying. I'm thinking it"s timing being pulled that's causing the dip in the torque curve.
 

IEATVETS

Enthusiast
Joined
Feb 16, 2004
Posts
2,348
Reaction score
0
Location
Cottage Grove, Wis.
Once you get the AF taken care of that car should make some good power! As far as I know Darren, nothing was done to the motor so everything should be stock. Wish I had some answers for you as to why it is running fat but I understand motors and electronics about as much as I can read Chinese brail.
 
OP
OP
CSXT802

CSXT802

Enthusiast
Joined
Jul 20, 2010
Posts
418
Reaction score
0
Location
Bushkill PA
Once you get the AF taken care of that car should make some good power! As far as I know Darren, nothing was done to the motor so everything should be stock. Wish I had some answers for you as to why it is running fat but I understand motors and electronics about as much as I can read Chinese brail.

no worries Duane. I'll get it figured out. Car runs good as is. There is just a little left with the current set up to be had.
 

Bexar80

Viper Owner
Joined
Jun 26, 2010
Posts
82
Reaction score
0
Location
San Antonio, TX
Your torque curve appears abnormal because of the scale that was selected. If the right side torque of the chart was scaled to the same intervals as the left side hp the curve would not look so wonky. Compared to my dyno chart your torque curve follows very close but I think you may still have more dip from 4 to 4.5k than mine. Start with the plugs and wires. It may also help to have a BG intake/injector service done. It made my car idle much better so I assume it probably helped in the higher range also.
 
OP
OP
CSXT802

CSXT802

Enthusiast
Joined
Jul 20, 2010
Posts
418
Reaction score
0
Location
Bushkill PA
Absolutely correct. Stock timing takes a dump from 4-5K and then picks back up above 5K. SCT will do wonders on this specific car.

Thank you. I was looking for someone to confirm what i was thinking. So you would you leave the fueling as is and just add timing where needed to clean it up?
 

EllowViper

Enthusiast
Joined
Mar 28, 2006
Posts
1,656
Reaction score
0
Location
Valrico Florida
As a starting point Yes. But only if you are running 93 vs. 91 octane there in PA. Basically, stock the engine starts out leans and ends up rich with timing taking some big swings along the way. You can view all these parameters in the SCT software. The stock tune is a very conservative tune for obvious reasons. You need to determine how changing the stock tune is going to be reflected in how you plan on driving the car. High load, high RPM you'd probably stay a bit on the rich side vs. quick bursts on the street for showmanship. Think about the orignal purpose of the car design and you can appreciate how it was tuned from the factory. Your tuner can work with you on how best to set the car up for how ypou plan on driving it. Have fun with it. Its a fun and relatively easy process.
 
OP
OP
CSXT802

CSXT802

Enthusiast
Joined
Jul 20, 2010
Posts
418
Reaction score
0
Location
Bushkill PA
As a starting point Yes. But only if you are running 93 vs. 91 octane there in PA. Basically, stock the engine starts out leans and ends up rich with timing taking some big swings along the way. You can view all these parameters in the SCT software. The stock tune is a very conservative tune for obvious reasons. You need to determine how changing the stock tune is going to be reflected in how you plan on driving the car. High load, high RPM you'd probably stay a bit on the rich side vs. quick bursts on the street for showmanship. Think about the orignal purpose of the car design and you can appreciate how it was tuned from the factory. Your tuner can work with you on how best to set the car up for how ypou plan on driving it. Have fun with it. Its a fun and relatively easy process.

Thank you for the input. You have cleared the waters for me. In my case would you do a mail order tune from a vendor. Or go all in on pro software for the sct ? I have no other mods planed in the near future. I know the car is being held back. I can feel it in that rpm range. I have 93 octane here in PA. After doing the dyno pulls we had to step out side as our eyes were burning from how rich the car is.
 

EllowViper

Enthusiast
Joined
Mar 28, 2006
Posts
1,656
Reaction score
0
Location
Valrico Florida
Personally, if your tuner is worth anything at all, I'd get the Pro Racer software and spend an hour or so with your tuner dialing in the car...both on the dyno and on the road. Ultimately, you will only end up changing a few tuning parameters to get the car where you want it...thus you can see why there is a mail order market for these sorts of things. If it were very complicated, there would be no way to do mail order tunes (generally speaking). I purchased all my stuff from Sean Roe without any drama. It is very easy software to use for just tinkering with a N/A tune and you can easily reset everything back to stock if you head down the wrong path. Plus once you get into the software, its interesting to see all the other engine parameters and how the engine is sort of tied together through the PCM. Someone once posted "I don't care to know how it works, just that it works." Well, I'm at the other end of the spectrum. I want to know how it works so I understand why it works.
 

Latest posts

Forum statistics

Threads
153,647
Posts
1,685,252
Members
18,227
Latest member
Kkustelski
Top