Hey guys, I ended up going with a couple of my friends who have Z06's, to this place in Elk Grove Village called Technical Performance Center on Higgins and *******. My friend with an open airbox 03 Z06 put down 363rwhp and 354 rwtq, my other pal with a Magnacharged Z06 put down 460rwhp and 411 rwtq.

Anyway, I had my car dynoed, I have an 02 SE Auto. The first time he ran it on the rollers, Geoff hit it, and it downshifted to 2nd gear, so he had to adjust when he hit it on the dyno. He finally got it right and we ran back to back runs for $75

Best of two runs - 175 whp 195 wtq. Now, consider BONE STOCK 6spd VQ35 Max's are doing ~210 whp and ~ 220 wtq....

I would have liked 185-190 whp, the tq Im happy with, maybe an extra 5 wtq would be nice...Geoff asked if I was using good fuel, which I do, but before I bought car in June, it was a rental car in NY. Who know what crap they were putting in the gas tank over there, maybe the lower octane ??!!

Geoff suggested I run 3 gallons of 100 octane and blend the rest to see if the car feels stronger, but Im not gonna do this every time I fill up....

I would think after me using 93 octane for three months, the system would have burnt out the remnants of carbon in the engine. Maybe I should use Mobil Fuels with the detergents ? New plugs, wires, or engine treatment ?? What do you guys suggest ?

Im going to Union Grove on Wednesday, and will post results when I get back. If this thing isnt doing 92 mph traps, Im gonna consider taking it in and complaining. We shall see.

 

Depends how they maintained the car in NY. I'd suggest new plugs and maybe a complete fuel system cleaning ie (Motorvac or similar). I assume you already took care of fuel filter, air filter, oil & trans fluid. Wires should be fine on an '02 right? Good luck.

 

I will have to try the fuel system cleaner. I haven't touched the fuel filter, or tranny flush. I was gonna do both at 30K miles. I will look at the plugs later today.

Thanks

 

Your numbers are about 15 hp/tq low. Autos dyno in the 190hp range and about 210 fwtq. 6spds hit 200-205 fwhp typically, and 220+ fwtq. 210 would be a tad high.

Yeah, check plugs and all general maintenance. If your tire pressures and even alignment was off that will all affect your dyno also.

 

I looked at other 02 dyno results, and the way I see it, I am missing 10whp and ~ 5wtq. Its not the end of the world, but since it translates into a tenth or two, it is significant.

Before I got to the dyno, I was hoping for at least 190whp and 200wtq.

After mulling this over for 12 hrs, I was thinkin, the VQ35 motor is rated at 255 at the crank in the Maxima. That's accurate for the 6spd guys imo. The true rating for the AT VQ's should be 230 hp...

With a 20% loss from the fly to the wheels, this should yield 185whp easy.

Kinda funny how Nissan underrates their tq, yet overrates their hp numbers. Most 6spd are doing ~270 lb ft and most Autos are doing ~250 lb ft, at the crank respectively, which is awesome either way.

The car seems to running fine, however I will get a fuel system cleaner, and go to the track on Wednesday, so that will pretty much give me the answers I need. We shall see

 

I wouldn't use any fuel additives, the 4th gen FSM says to stay away from those. Maybe yours does too, or not...

 

The 6 speed and the 4 speed auto all have the same rating (255/246). After taking both auto's and manuals to the dyno, they both dyno low on HP and higher on TQ. This is pretty much across the board for all VQ35 platforms from 2001-2003 (Pathfinder, Altima). What they actually have is 245hp/265tq. Some are slightly lower than others, some are slightly higher than others, but your car is definitely more than slightly lower.

 

err..well, not exactly. It's just a fact that automatics will never dyno as well as manuals because they're not as efficient. The power the engine is putting out at the crank is still the same in either case.

255 hp isn't really accurate for the engine, though. A 260 HP Acura CL-S 6spd dynos at 217 fwhp (repeatedly, and that engine is not under or over-rated), yet most 02-03 6MT Maxs dyno at about 200-205 fwhp. Like Quicksilver said, the true crank rating of this engine is more like 240-245hp and 265tq. If there was really 255hp, the cars would be dynoing repetetively at over 210 fwhp stock but they don't. Maybe in a few isolated cases, but not generally.

Most automatics of this general size see about a 22% "loss" on a dynojet.
Most automatics of this general size see about a 17% "loss" on a dynojet.

 

What about an ECU re-program, I think I saw a TSB on this???