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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Reving past stock rev limiter

  • Thread starter Thread starter stangboy
  • Start date Start date Feb 26, 2004

stangboy

Founding Member
Aug 31, 1999
3,932
469
194
New Orleans, LA
Feb 26, 2004
#1
  • Feb 26, 2004
  • #1
Hey guys,
2 of my boys(their twins) just did a heads and cam swap on their 306. they already had a GT-40 intake. They put Trickflow heads and a Lunati solid lift(flat tappet) cam. They can rev right past the stock rev limiter past 7000rpms. I didn't believe it until I drove it myself. They didn't put a chip in it or anythng. The rev limiter worked when they had their F303 in it, but now its like the rev limiter isn't even there. Not like they want the rev limiter but I was just wondering how this could happen. The computer is probably so confused though because it searches for idle. One minute it'll idle at about 1000rpm then it'll go up to about 1500-1800, and it'll come back down to 1200. So, maybe that's why it revs past the stock 6250rpm rev limiter. I must say, it sounds wicked as hell. The lope is so rediculous it sounds like the car is talking. I love it. It actually has me wanting a solid lift cam....it revs so high so damn fast and it keeps pulling. I love it!!
 
N

noslow5_0

New Member
Nov 7, 2003
422
0
0
dallas tx.
Feb 26, 2004
#2
  • Feb 26, 2004
  • #2
huh mine does the same thing... ive taken it to almost 7 and nuttin... I thought i was the only one with this!!!! o well i love the way my e cam sounds i bet the f is even better!!!!
 

89MustangGX

I have nothing productive to add!
Jul 3, 2001
10,262
1
0
Mill Creek, WA
Feb 26, 2004
#3
  • Feb 26, 2004
  • #3
Without any computer work it doesn't happen. Most likely the tach is just very far off--seen that happen in alot of these cars.
 
N

noslow5_0

New Member
Nov 7, 2003
422
0
0
dallas tx.
Feb 26, 2004
#4
  • Feb 26, 2004
  • #4
well i have both an autometer tach, and the stock one.... The stock one seems a little off at idle, or maybe its a combination of the two....
 

89MustangGX

I have nothing productive to add!
Jul 3, 2001
10,262
1
0
Mill Creek, WA
Feb 26, 2004
#5
  • Feb 26, 2004
  • #5
noslow5_0 said:
well i have both an autometer tach, and the stock one.... The stock one seems a little off at idle, or maybe its a combination of the two....
Click to expand...

You got me on that one...it's just not possible to bypass the computer without bypassing the computer?
 

stangboy

Founding Member
Aug 31, 1999
3,932
469
194
New Orleans, LA
Feb 27, 2004
#6
  • Feb 27, 2004
  • #6
So, why all of a sudden the thing isn't working? It worked when they had the F303 cam in the motor. But I'm serious, it revs right past 6250rpms like if it wasn't there. I drove it myself. I didn't believe it until i drove the car and saw(and felt) it for myself.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Feb 27, 2004
#7
  • Feb 27, 2004
  • #7
The factory ecu limits rpm to 6250. So, either you're not exceeding it and your tach is reading incorrectly (highly likely if your 7 grand reading is from the stock tach), or you are exceeding it and that means the ecu is malfunctioning, or someone has slipped a chip in while you weren't looking.
 
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