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1991 lx 5.0

  • Thread starter Thread starter projectcheapersleeper
  • Start date Start date Nov 5, 2018
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projectcheapersleeper

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clovis
Nov 5, 2018
#1
  • Nov 5, 2018
  • #1
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*.
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
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polk county florida
Nov 6, 2018
#2
  • Nov 6, 2018
  • #2
Are you running stock ignition?
93 octane?
 

Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
Mar 2, 2003
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Greenville, NC
Nov 6, 2018
#3
  • Nov 6, 2018
  • #3
What injectors and MAF meter are you running? What's the compression of your setup?
 
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projectcheapersleeper

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clovis
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#4
  • Nov 6, 2018
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Yes I’m running 91, also I have a MSD Ignition set up
 
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projectcheapersleeper

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#5
  • Nov 6, 2018
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I have 32# injectors and I’m running a dbx mass air. Compression is 11-1
 

Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
Mar 2, 2003
909
415
113
Greenville, NC
Nov 7, 2018
#6
  • Nov 7, 2018
  • #6
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?
 
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projectcheapersleeper

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Nov 7, 2018
#7
  • Nov 7, 2018
  • #7
Dan02gt said:
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?
Click to expand...

I’ve used torco octane booster and no difference
 

a91what

SendMeUrDataLog
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Nov 7, 2018
#8
  • Nov 7, 2018
  • #8
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.
 

a91what

SendMeUrDataLog
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#9
  • Nov 7, 2018
  • #9
also what timing box are you using?
 
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projectcheapersleeper

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#10
  • Nov 7, 2018
  • #10
a91what said:
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.
Click to expand...


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
 

a91what

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#11
  • Nov 7, 2018
  • #11
projectcheapersleeper said:
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
Click to expand...
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??
 
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projectcheapersleeper

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#12
  • Nov 7, 2018
  • #12
a91what said:
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??
Click to expand...

Company isn’t around anymore. The car was in the mustang and ford magazine called the project cheaper sleeper. The car was built in 2013. Finding info on this computer and tuning is ridiculous
 

a91what

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#13
  • Nov 7, 2018
  • #13
gotcha, I am a megasquirt guy myself.... so if you ever have any tuning questions feel free to ask. I hang out in the digital tuning section of the forum.
 
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