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

Max RPM for shifting?

  • Thread starter Thread starter spoulson
  • Start date Start date Dec 16, 2009

spoulson

Member
Nov 3, 2009
76
0
7
Middletown, DE
Dec 16, 2009
#1
  • Dec 16, 2009
  • #1
I bought this car not long ago and is now running smooth after fixing up some problems. One day this spring I plan on taking the car out to the track to see what it'll run. So, I was wondering what max RPM you think I can take the engine to before shifting. I know this is a little armchair racing, but I'm just looking out for some definite do's and don't's.

My major mods are in my sig. As far as the valvetrain, all I know is the pushrods are hardened and springs are duals. I don't know the brands or specs of the springs. RRs are FRPP 1.6's. The AFM N-4 cam is pretty lopey and wants to pull hard past 6k rpm if I let it. The oiling is upgraded with a Melling high volume w/ hardened shaft. Rear axles have been upgraded and are 5-lug, but I don't recall the spline count.

Would you guess 6500 is safe? 7000?
 

Jaswir

Member
Mar 31, 2005
578
0
18
Orlando, FL
Dec 16, 2009
#2
  • Dec 16, 2009
  • #2
im pretty sure the REV limit is around 6200. you pretty much stop making power around 5500. just depends on ur setup
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Dec 16, 2009
#3
  • Dec 16, 2009
  • #3
6200-6500 is where that combo will want to be shifted. Better have good valve springs.
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
32
128
Saint Louis, MO
Dec 17, 2009
#4
  • Dec 17, 2009
  • #4
factory fuel shutoff is ~6,250 rpm, to get past that you need a chip or find an old rpm extender to use.
 

spoulson

Member
Nov 3, 2009
76
0
7
Middletown, DE
Dec 17, 2009
#5
  • Dec 17, 2009
  • #5
I guess I overestimated the RPMs this engine can handle. I've taken it to about 6k and it handled just fine. Sounded mean!
 
T

THOR74

New Member
Dec 5, 2009
72
0
0
Ontario, Canada
Dec 17, 2009
#6
  • Dec 17, 2009
  • #6
At the risk of stating the obvious, I would suggest first establishing a generally safe max rpm in your mind first, and then test the car out. You may end up hitting a level where anything past it is really not pushing the car optimally anymore and you would do better to get the next gear in.

As was stated, this all depends on many factors, including your tranny and rear end gears.

Experiment with the car without blowing it up. Focussing on higher rpms may not actually get the car going any better at all. Focus on the pull instead.

Get to really know the car in this way and have fun with it. Best of luck!
 
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