Ok guys, I need some help in figuring out why I am still stock. I dynoed at 167hp, here are the specs on my car:

97 5spd, Place Racing CAI, WS Y-Pipe, Greddy full catback exhaust.

I recently did a compression test at 3 cranks and each cylinder I got about 190psi. The 1st crank I got about 110, 2nd-3rd crank brought it up to about 190. If I did more than 3 cranks it would go 200+. So I'm a little bit over standard specs.

The only check engine light I have is EGR, think I have a leak in the hose.

So I don't know what else it can be, thought it was the engine but doesn't seem like it after the compression test.

Please HELP !!!

 

Compression sounds fine. Was that with a warm motor?

Has for the EGR, if you have a leak then chances are you have a vacuum leak. Vacuum leaks are deterimental to performance and it is possible to have a small leak and the car runs fine. I had a vacuum leak on my intake (don't ask) and it caused me to be .2 and 2mph slower yet the car run perfectly fine. A bad vacuum leak will make the car sound and run like Harley Davidson installed their cams. You should really check your vacuum with a gauge. I've tested about 7 4th gens now and the vacuum across all the cars was a very steady 20-21 Hg. This is at ~1200' above level also (vacuum is dependant on elevation).

If you do have a leak, fix it.

Your low numbers may also be a result of the dyno. Some dynos run higher or lower than others. It's really not the hard numbers you should be concerned about (assuming the car is in good running shape), it's the gains/losses you make with the mods. Most importantly, dyno on the same machine everytime. Nealoc187 who runs 13.4s@102mph only made ~185fwhp on his dyno which means he's making a lot less dyno power than most other 4th geners with the same mods. Like I said, some read high, some read low. Go to the track and see where your at. There are quite a few good tracks in you neck of the woods.


Dave

 

Yes the compression was with a warm motor.

I've been to the track a couple of times and the times I got was 15.4 - .5
I should be in the 14s so it's not only the dyno, it's the track to that proves I have lost power.

So your saying that EGR will effect performance? The code I am getting is 0302 - EGR System Hi/Low Flow.

Thanks ...

 

With just a y-pipe and filter, I only dynoed at 161, so don't feel too bad.

 

wait i thought our cars have 190 hp

 

190 is at the crank, not at the wheels, he's talking about WHEEL HORSEPOWER

 

You have high compression which means you have LOTS of build up in your cylinders. Put some ATF into each cylinder through the spark plug holes and see if that helps.

 

Good, you tested compression the right way.

As for the 15.4-15.5, I need to know your trap speeds and 60 foots. Years ago when I first started racing my Maxima I was getting consistent 15.3-15.4s@91-92mph with 2.4 60 foots. I learned how to launch the car and which rpms to shift at and I started to get my 60 foots into the higher 2.2 range and I was getting consistent 14.8-14.9s@93mph with no other changes to the car.

The EGR can affect performance, but it's the vacuum leak you said you might have which would be my biggest concern. Test the car with the vacuum gauge and get some readings.


Dave