Hi Guys,

I thought it would be best to get more information from Evom as I am getting conflicting stories with different workshops

My Evo is down on power through the midrange. Its from about 3500rpm to redline and has a consistend loss of around 10-15 kw at the wheels through that rev range.

I am running a new motor in the car, as the old motor got a little tired. The builds are identical apart from the new motor having ARP head studs.

The car is running cam gears and 260deg cams both in and ex, and the cam gear settings were on neutral when it showed the power difference. The old motor tuner said he fiddled with the cam gears on the old motor, however the new tuner doesnt believe it is the gears.

So far I can confirm

- Car doesnt use oil or water
- Compression is great, 160, 165, 165, 165 psi
- Turbo and exhaust system remain the same
- Boost curve on dyno remained the same
- Cam gear setting are in a neutral position but the workshop says it wont make the power back by adjusting the cam gears
- The gearbox is different as I went from a 6spd to a 5spd but ratios are basically 1:1

If the workshops believes I wont gain back my midrange by adjusting the cam gears, what exaclty would the problem be? Any thoughts if the motor is healthy?

 

I feel that the cam gears can make a difference. I going to find a nice flat stretch of road and do some more adjustments to mine. I will post up the results. My intial testing on my dyno vision logs show that I was able to shift my power band around with the cam gears.

 

Im pretty sure its all in the cam gears. I just dont think it would be anywhere else and the workshop cant even tell me what they would diagnose next... Sounds like they just want to have the car so they can charge me a few $$$ for nothing?

 

Those cams are pretty small, what turbo are you running? Fuel type?

Is the current tune for the old or new motor?

 

Current tune is based on the new motor and its running the Evo 9 turbo with E85.

I also changed gearboxes from a 8GSR 6spd to a 8RS 5Spd (Japanese Spec) between the dyno run on the old motor and the new motor.

 

did the afr change maybe?

 

Adjusting the cam gears will move the powerband, but will not usually provide an across-the-board gain/loss.

 

Would it more than likely be the gearing of the boxes? I.e. one was 5spd, the other was a 6spd? That will shift the band completely as far as im aware?