stiff valve train and large cams cause faulty knock reading?

[gtrjon]

yup basically after talking to a few tuners we will be ignoring the idiot light on the pfc and pressing forward while using equipment to listen audibly for det while under high boost. i let you guys know how it goes. shooting for 650awhp at rg

[Super_Dude]

Why are you using such stiff valve springs? I would switch for a more appropriate valve spring first. If that doesn't solve your knock problem it will at least prevent premature wear on the valve train.

[gtrjon]

i ordered my head set up all at once. I originally ordered cams with 280 duration and 10.8 lift. thus the dual valve springs and tomei buckets to compensate for the large lift. well when my cams showed up they only had 10.25 lift instead of the 10.8 and i didnt have time to wait another 6 weeks so i just ran it.

[Dragon Humper]

i ordered my head set up all at once. I originally ordered cams with 280 duration and 10.8 lift. thus the dual valve springs and tomei buckets to compensate for the large lift. well when my cams showed up they only had 10.25 lift instead of the 10.8 and i didnt have time to wait another 6 weeks so i just ran it.

And that should give you a nice 1000rpm bump in range before you have float issues. Or extending greatly the life expectacy of the springs themselves.

I would do your tuning with some C16 mixed at 50/50 with 94. That way you can see what she can really do without risking a hole in something. FYI my tune has 32 deg of ign. timing all the way to 1.6 bar, that's why she rotates the earth so well. I can run that curve with only 94 up to 1 bar with no issues and traps at 122mph.



Jon.