Hello Guys,
Just wondering if anyone else got the same problem-dissapointment? I have an 04 G35 Sedan. I have install the following: K&N Cold Air Intake, Motordyne Spacer, Stillen Headers and Exahust (Gen2) and a UTEC. I took my car to japtrix in Palm Beach, FL. They could not get more than 225 HP on their Mustang Dyno. After running it many times, Roger, gave up and told me, "it is what it is." He told me that something was holding down power to the vehicle; he showed me other G35s AT 03-04s results after tuning them and where on the 240s+ hp. Has someone else got the similar low results with a car similar to mine?

 

Did you have a previous baseline dyno for your stock car? Otherwise, these numbers mean absolutes nothing.

Remember, a dyno is used for tuning purposes. If you're looking at just a static number itself, without comparing it to a personal previous dyno with a different setup(at the same location/same dyno)... it just doesn't make any sense.

The number is just a number without a baseline.

If you really wanted to see improvements, you would need a stock baseline or drag race the car (before/after).

.

 

How many HP before he started tuning?

He should have made an initial run to determine how to tune...

 

Initial baseline was 201. Same specs on the car, but with SSV Manifold and no motordyne spacer. After removing the SSV manifold and installing the motordyne spacer the numbers jumped to 219.x. After tuning it, the highest number was 225.9 hp.

 

wow the ssv lost that much power.

 

Could you have clogged cats?

 

I am not sure. My cats have like 60K miles; for how long do they last?

 

Post pics of your dyno plots overlaid on other vehicles plots with similar setups being tested on the same dyno.
This may give clues.

 

I went to the 1/8 mile track today and this are my numbers:

Raced against:
I)BMW 650 Me (AT, TC OFF and 1.5K RPM)
RT: 0.616 1.069
60 FT: 2.336 2.383
MHP 71.8 75.2
E.T: 9.913 9.630
Winner
II) G35 Coupe MT 07 Me (AT, TC OFF 1.8K RPM)
RT: 0.466 1.031
60FT: 2.478 2.317
MPH: 73.8 75.5
E.T: 9.839 9.547
Foul Winner
III)I)BMW 650 Me (Triptronic, TC OFF and 2.0K RPM)
RT: 1.166 1.095
60 FT: 2.419 2.384
MHP 74.1 76.2
E.T: 9.774 9.544
Winner =)
IV)I)BMW 650 Me (Triptronic, TC OFF 2.0 K RPM)
RT: 1.118 1.205
60 FT: 2.290 2.353
MHP 74.1 75.7
E.T: 9.655 9.573
Winner =(
V)Prelude 92-95
0.606 1.043
2.439 2.372
68.4 76.6
10.617 9.511
Winner

 

If you're trapping 75/76mph in the 1/8th, then you definitely have something holding back the power. 5AT's should trap about 75/76mph stock, even in the heat(~2k DA).

 

Yep, you're down 15-20HP best guess with your mods. If you're going to keep the car, get a diagnostic done with fuel ratios and what you're timing is doing. It would be interesting to disable the UTEC for a few days and just let the stock ECU do its thing and see where you are. Who knows, maybe the old SSV map is still screwing things up?

You could also be lean with the headers causing the ECU to pull timing due to ping you may not even hear. The diag. will show that too.

Have you ever had highflow cats? If so, they could have been FUBAR and blew chunks into the rest of your catback. If you are not the orig owner, who knows what was on there.

 

Do you know any place here in south florida where I can have a good diagnostic done on my car? I would have expected that the company that tuned the utec had done it, but they did not. That was not included in the price and I was offered to bring my car again, but it is too far, like 1.5 hours driving. I live in Miami.
Thanks,
Mario

 

I never had high flow and I replaced the whole exhaust and headers. The computer is changing mappings. I noticed it because the relay is picking up at 6.5 K rpm and sometimes it goes all the way to 7.5k+ as setup on the UTEC. I als feel the car much more responsive "awake."I noticed it does that after I tank it. I always use 93(the most expensive), but the car seems to prefer certain gas stations, like chevron and Hess.
Regards,
MArio

 

Did you ever get your problem fixed?
I am having similar problems with my 04 sedan. It doesnt feel any faster than stock with intake and a stillen exhaust...
What ecu should I look into, and does anyone know of anyone who does diagnostics in orange county? new to the area...

 

Not yet. I called japtrix and they gave me an appointment for next saturday. They will try to diagnose and fix it. I really hope it is an easy-not expensive fix, for I do not have too much money now to spend on the car; besides, I have already spent like 4K on the car.