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Forgive my ignorance but Lca?

Lobe Center Angle, so 11deg adv on in and 9 deg retard on exhaust, then tune, will change what you think about VCT :yes:

They are both stock cam motors, vct is only 5degrees advance on inlet right?

Im fairly certain its a 20deg change :/

Edit, Beatin to it again :(

or try taking your motor thats been dialed in, and doing power runs at a further 20 degree intake retard, or a 20 degree advance, and see if there are any areas where you can from the extra advance, this will show you the use for vct

We tried heap of different settings and where it is is the best overall, there was no point where any adv/retard would improve what it currently is :)

20 deg either way at any point would be a massive step back

i was fairly sure it was more around a 20 degree advance, and stock cams are in the best postition for stock aplication, emmitions, etc, not nessasarly power so there is gain to be had there

edit yeah was beaten twice there

but your results seem strange to me, when i get my dyno in a couple of months ill revisit this thread with some playing around on the dyno with cam adjustment angles in a few conditions

Edited by Scott Black

this is why RB26 owners (that have deep pockets) end up retrofitting VCT OR HKS V-CAM onto their heads..

It's not about overall power, it's about usable power...

I definitely prefer my turbo on full noise at 4000rpm instead of 4500rpm (making up numbers here).. but if you go through Hypergear's thread you will see similar turbos produce similar power levels on both RB25 & RB26 motors and the only difference is the lag.

Yes the RB26 is 0.1L different, but I would prefer VCT any day of the week.

mm yet if hes not gaining anything below 5k by advancing the cam further then its not any more laggy with vct off, (strange imo as theres normally a gain) yet if hes advanced it so its already at its best setting for say the 2-5k range, then it should get a gain by retarding it above this leve, why i think its strange as hes saying thers no gain anywhere by changing the cam timing from what hes set it to, and thats very very strange

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