1991 lx 5.0

so i got a 91 331 stroker anderson n41 cam and ported gt40 heads and intake. im having a detonation problem at WOT with the mass air hooked up. then with it unhooked the car would run but detonate at any rpm over 3k. inital timing is a 7* and total timing is at 35*.
 
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I'm not familiar with that DBX mass air meter, but it looks like it is tunable. Can you use the software to add a little fuel in the range that you are pinging? Have you tried adding something like race fuel or octane boost to get the octane up a little?
 
35* total is too much with pump gas and 11:1 comp. Stock 5.0 WOT timing is 28* total. 30-32* with the timing bump most people do.

Lower the Total timing to 30* and the detonation will disappear. 28-30* is the most i would consider on that setup with pump gas.
 
35* total is too much with pump gas and 11:1 comp. Stock 5.0 WOT timing is 28* total. 30-32* with the timing bump most people do.

Lower the Total timing to 30* and the detonation will disappear. 28-30* is the most i would consider on that setup with pump gas.


I have a Modotek computer where I can tune online. I just got the car. Everything was tuned by the guys at Modotek. That’s what I’m guessing is timing is too far advanced at WOT. Initial timing at the moment is at 7* to see if that would help at all but it didn’t. So I’m thinking about moving that back up to 12-13 then bring fix the tune to come down to 30 total timing and see what happens there
 
I have a Modotek computer where I can tune online. I just got the car. Everything was tuned by the guys at Modotek. That’s what I’m guessing is timing is too far advanced at WOT. Initial timing at the moment is at 7* to see if that would help at all but it didn’t. So I’m thinking about moving that back up to 12-13 then bring fix the tune to come down to 30 total timing and see what happens there
set base timing to 10* then the total needs to be 28* start here as a baseline. I have never used a modotek, got a link??