Low dyno numbers

[cobra_bill]

I had my '03 dynoed today and was disappointed with the numbers. The only mods are a drop in K&N and a magnaflow catback and the car has 1500 miles on it. It only made 347 hp and 352 tq.

The air/fuel went off the scale rich at 4500 rpm so maybe this is the reason it was so low. This was on a dynojet and the numbers are SAE. I can view the run in the dynojet viewer but I don't know how to post the graph here.

Could clogged cats cause this? If I run the car hard there is a nasty burning smell from the exhaust.

I'm trying to figure out if the car has a problem or if I should just put a pulley/chip in it and have it tuned.

Bill

 

[kpinco]

Sounds like clogged cats!

 

[KDog]

Mine ran off the scale at 4500 also - still pulled 360 after a 20 minute or so cool down period. From what I've seen, pretty much everyone (stock or close) goes rich around there. Could be the cats, a few others had this problem also.

 

[FuShnickens]

i know how you feel. when i first dyno'd my car w/ 1500 miles on the clock it put down a depressing 373/338 sae. only mods at the time were the kb cai and mac 3" (both are no longer on the car now). my a/f went off the charts rich at 3800rpm and never came back. had the dealer look at it and everything was "in spec". you could have the same issue i had - incredibly crappy stock factory tune.

 

[bluntman]

here's a graph of my stock dyno, 3 pulls, last one was the best at 375/374

the a/f line has a big blip in the last run, but you can still tell what it would have read

 

[cobra_bill]

Here is a scan of the graph. It looks good until 5500 and then a big dip.

Bill

**PIC SIZE EDITED BY 03DOHC**

 

[PhillyCobra]

I think your numbers are way low for your mods (see my sig, which is perhaps a little higher than others, but close). Run is very rough at high RPM's-- could be clogged cats, ignition problem, perhaps Fuel Rail Pressure Sensor. Most people with your mods don't go quite so rich up high. I think you need someone knoweldgable to check your car.

 

[Shadowgray03]

Originally posted by cobra_bill
I had my '03 dynoed today and was disappointed with the numbers. The only mods are a drop in K&N and a magnaflow catback and the car has 1500 miles on it. It only made 347 hp and 352 tq.

The air/fuel went off the scale rich at 4500 rpm so maybe this is the reason it was so low. This was on a dynojet and the numbers are SAE. I can view the run in the dynojet viewer but I don't know how to post the graph here.

Could clogged cats cause this? If I run the car hard there is a nasty burning smell from the exhaust.

I'm trying to figure out if the car has a problem or if I should just put a pulley/chip in it and have it tuned.

Bill

Before anyone can make an educated comment we need to know what brand dyno these numbers are from, if its from a dynojet they are a tad low, if its from a mustang or suerflow those numbers arent bad at all since they are about 10% lower than a dynojet (and more realistic I might add).

 

[03Redfire Cobra]

You need the predator with the performance tune!

 

[SlammedSVT]

The car will get faster with break in.

 

[PhillyCobra]

The numbers were stated to be on a Dynojet and the car has 1500 miles. I really think you should see if there's something wrong with it before you try to up the power with mods.

 

[Cobra-Master]

My car is bone stock (no mods), and I dyno'd on a Dynojet this weekend, here's my graph. The numbers are SAE. I'd say you need to have the dealer check it out.

 

[cobra_bill]

Thanks for the replys guys. As I said the numbers were on a dynojet and were SAE. I noticed when I ran the car that the blower would whine until 5500 rpm and then would go silent but the boost gauge still was showing 8 lbs. Maybe something is causing the bypass to open up early.

I will take it to the dealer and maybe I can get them to swap out the cats.

Bill