[^Trickster^]

I have my car currently tuned and running fine, however, at the time of tuning I had no time to alter the cam settings due to a couple of problems, my exhaust cam is at about 125degrees from memory and i can see 900 degrees C of egts when totally hammering the car, I am assuming the exhaust cam timing is responsible and does need adjusting on the dyno.

My question is, can you alter the exhaust cam without seriously effecting the tune? I know I will be altering the engine VE, the question is just how dangerous of a risk is it. I know moving the intake cam messes up all the ignition timing etc

Any info would be great

Thanks

Graeme

 

[CkretAjint]

if you are going to dyno tune with the EMS, why not spend and hour more ahead of time and get your cam timing done right?

 

[^Trickster^]

Well the dyno is a 3hour drive and I was hoping to just be able to play with the exhaust cam. I will be going back down at some point, but dont have the money for additional tuning at the moment.

Graeme

 

[erioshi]

I've spent literally 30+ hours on the dyno tuning my Evo in different configurations as it has gone through development. At least 5 of those hours have been spent testing different cam timing configurations (before and after serious headwork).

In all of that testing I have never needed to adjust fuel, boost or ignition timing for cam timing changes. That said, I'd still check things when you can - engines are spendy.

 

[^Trickster^]

Thanks Erioshi thats pretty reassuring, anyone done this with a power fc EMS before? or anymore information?

Graeme

 

[RickyB]

If you have a conservative tune at around 11.5-11.7:1 AFR and timing at least 3 degrees away from the first onset of detonation then you can play around with your cam settings to your heart's content without having to worry. Once you have the cams set where you want them, then you can fine tune right to the edge of sanity if that is what you want to do.

 

[^Trickster^]

Thanks for the info Ricky, The engine was apparently tuned to 11.5:1, ill email the tuner and get a copy of the AFR sent, he said there was minimal signs of detonation and the engine was doing really well, I was just hoping that moving the exhaust cam would maybe give a bit better power due to it being so far out and bring down the EGT as I remember you telling me that 125 degree setting would cause the higher EGT

Is it possible to predict what kind of difference could be made to the power/torque output from my dyno graph? I was hoping the HKS settings might keep the torque from dropping off at the end, but I am really not clued up in the tuning area at all.

Thanks

Graeme