![]() on any changes, I would have always an eye on boost and AFR values. But in my experience this hasn't too much effect. if you feel that it gets better with exhaust cam timing adjustments, you could move around both cams together. If you found a suitable setup, start to play with exhaust cams. At the begining I would do big steps of adjustment to clearly see what happens with the torque band. Retard for more top end at the cost of later and more aprupt spool up. Advance inlet cam spools the turbo quicker, more midrange, but makes less top end power. We want find sloly the impact from camtimig to the torque band and don't want get fault results by other variables like turbo efficiency.) (If you would leave your turbo and ignition timing at the edge and your VE get with a cam timing change higher, the engine will start to knock and the turbo will fall out of his efficiency rage. retard the tune to a quite safe state, get sure that your tune is a few degree back from the knock treshould and the turbo doesn't run at the edge. If necessary make also small adjustments to the Fuel map to hold AFR in the same range through out the tests. This way the engine should not change power with slightly different AFR values after changing cam timing Still, I would always pay attention that your boost sits exactly at the same level after a cam timing change. For turbo engines thats usually between 11.5 and 12.5. If possible set the AFR into the middle of the window where the engine makes most power. Tune the engine roughly and get a feel where the knock treshould is. Intake cam timing has a much more influence to the torque curve than exhaust cam timing. That means the AFR's and knock treshould does move also. Of course there are different ways to find the right cam timing.įirst, a change in cam timing changes the volumetric efficiency. How much effect does it have on fuel tuning? I imagine there would be more effect on spark timing? does advancing the inlet cam and closing the LSA usually require more or less advance? pretty sure its only on the inlet cam but does it advance the cam from where it sits with engine off or retard? I know I can turn the motor over by hand first to check clearance but a little worried about the VCT system. Only touch the intake or the exhaust and not even touch the other.Īlso what effects would advancing both the intake and exhaust cam have? can it be beneficial?Īm a little worried about valve to piston clearance, not sure what the clearance is standard. Reverse of #1 and retard the exhaust cam first?Īdvance intake and retard exhaust at the same time? then retard the exhaust cam 2 degrees and check results and continue in increments which following method would you use.Īdvance the intake Cam 2 degree's and leave the exhaust where it is, Check results. What sort of procedure do you follow when making adjustments? ie the engine is custom tuned for the current setup with the stock cam dial in. Hey, Im interested in playing around with some Cam gear adjustments on my RB25DET just have a few questions.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |