Mods: ES Shifter Bushings, that is all
Transaxle: 6 spd MTX 79k miles on engine and trans.
Location: St. Louis, MO (Performance By Joe)

Note: The dyno was loaded to 21% instead of the normal 16% which turns in about a 5% lower reading than a normal dynojet because this shop is a Viper specialist and has to load the dyno this high because of the repeated 1000+ hp pulls made on it regularly, so really I should sit somewhere in the low 220's STOCK, but I will get another dyno shortly to see.



Here is my concern..there is a flat spot in my power curve around 3500 to 4000 rpm, any ideas? We tied the valve on the intake open and it didn't change anything. Also there is a huge dip in the torque curve in the same rpm range..any ideas?

 

Those numbers look really good for stock. If you were in the 220's I'd suspect the dyno was just reading high. The dip is normal.

 

Really nice numbers...Thanks for post...

 

I would have been suspicious too, however, this dyno was compared with another just down the road with the same car a mere hour apart from one another and the camaro put 476whp down on his dyno then 500 on the other dyno with nothing touched. These were both the same model dynojets...So I think I will make a trip to another dyno and see what it comes out as just out of curiousity, though these numbers seemed higher than most stockers on here..

Oh well, thanks for the kind words and for the assurance that the dip is normal. Any idea why that big dip occurs?

 

The dip is because of the dual stage intake manifold - the curves dip briefly as the power valve opens at 3600 rpms. The power valve is closed from 1800 rpms to 3600 rpms, effectively lengthening the intake manifold runners and giving you that low end torque, and opens beyond 3600 to shorten the runners so the car can breathe better up top.

Some of the posts in this thread should help you understand it better:

http://forums.maxima.org/5th-generat...-2k2-vias.html

 

I understand what it does, the VRIS system on the Probe is the same deal, but there is not a big dip or flat spot from it...just didn't know if it might have been something else. Thanks though!

We tied it open for the second pull and the dip got worse on the torque curve, because we suspected the valve was the cause of the dip on the first pull.

 

Instead of doing what you did (tieing it open), you may want to pull ( as in d'c {disconnect})the actual vacuum line that feeds it (VIAS).

Either way, nice values, and what are your plans?

A word to Puppet......... TF kid, you think you can rock my forum now

 

Nice numbers

 

They are, aren't they? ZOMG!

 

Puppet is right, the dip is from the VAIS opening. I've dynoed several times and it's always there. Even tuning wont smooth it out. It's nothing to worry about.

The numbers look about right for stock if you look at the curve. Most of the bolt on mods make power after 3800 RPM and don't have much affect on PEAK torque which spikes at a lower RPM. If you slapped on some headers, exhaust, intake and a tune your PEAK torque would be about the same. You would have much more torque in the hifher RPMs though. That would increase the HP number by a good bit.

 

I might try that next time..I am not too worried about it though since it sounds like it is normal, thanks for the info!

As for plans for it..not much, want to do the GAB, maybe a ground kit, and the timing advance. Maybe down the road more, but not much. I am still in the process of finishing my Probe build so that is where all the money is going for now.

 

I know for one that I made more torque than 232 when I dyno'd... You thinkin honda?

 

I just now noticed the fat A/F after 5200 rpm. Did they use a tailpipe sniffer or take out an O2 sensor?

 

tailpipe sniffer

 

What was the peak torque when you ran and what mods?

 

Nice wheels sparks...