I've done my street tuning on 93 octane at about 19-20 psi (on the AEM MAP, which is about 22-23 on my Defi boost gauge) so far and have peak timing at around 20 degrees at 7500 with 11.3ish AFR.

Now I'm ready to see what the WR turbo can do at higher boost. If I put in some ~100 octane (probably will be mixing VP104 into a little bit of 93) and turn the boost up to 24 or so (and with the WR I might be able to actually hold that to redline), how much timing should I expect to be able to run up top without detonation?

I'm not sure whether the extra boost cancels out detonation resistance of the higher octane, or whether I should even expect to have to reduce timing for higher boost even with the race gas. I also know that 100-104 unleaded is a far cry from C16.

Also, I've heard so many horror stories of head stud installs causing oil leaks, etc., that for now I'm sticking with stock head bolts, which I THINK should be okay at this boost level as long as boost doesn't spike over 25 psi.

Any advice would be very welcome.

 

You are not going to know how much timing you can run until you try. This is how it is done on a dyno. Step it up very slowly unitl you see knock and then back it off a bit. Aslo What is this about head studs causing oil leaks? I have never heard that before. Can you elaborate?

 

I was just trying to get a ballpark idea on the timing. I'm not sure where to even start. If I'm running 20 degrees peak timing on 93 at 20-21 psi, where should I start for 24 psi on 104 octane? Would my pump gas timing be a good starting point, or is that too high?

As far as head stud issues, I've just seen a few too many posts with people posting issues with HS's and very few with people popping head gaskets with stock headbolts, except with bad tuning.

 

I would start with your pump gas timing and just turn the boost up. It seems like a conservative timing map.