Well we had an 04 on the dyno today and as many people know, the manual cars are a pain to dyno due to needing the front wheels spinning. Well we've fixed that issue by figuring out the right fuses to pull.

In the box with the ECU we pulled the big 40amp fuse and fuse 1-4. Unfortunately it looks like (now that I have a service manual in front of me) we cost the engine power by doing this.

It seems like fuse 1 (15A) is for the traction system, fuses 2 and 3 (15A) are for the engine control relay, and fuse 4 (40A) is for the air pump. We tried pulling fuse 5, but that's the fuel pump and you kind of need that one.

The interesting thing is that the car pulled to 6200 RPM (might have went higher now that I think about it) with zero issues except for a lack of power.

I've driven this car for the past day or so and it feels very strong. As a base of comparison I drove it back to back with my vette, and the Xfire seems stronger. However when put on the dyno the results are much different. The vette put down 240 RWHP and the Xfire only 175 RWHP, even worse the vette had 260 RWTQ and the Xfire 178 RWTQ. Now I can understand a 10-15 HP difference being there, but there is no way on the street the Xfire is giving up 70 RWHP to the vette.

This brings me to the conclusion that one or more of the above fuses will allow a full uninterrupted run, but at the expense of some serious power, how much I do not know.

My 05 Crossfire with intake and exhaust (nothing else) put down 198 RWHP on the same dyno. The 05 and 04 fuse set up is different so the above fuses are not pulled on the 05.

Anyone else experience anything like this? We were using a Mustang dyno which spins the front wheels for a while, but the distance was killing us and this dyno is 2 mins away.

 

anychance there is a voltage boost circuit to the fuel pump? Maybe one of those fuese adds more pop to the fuel pump past a certain engine load? just a WAG