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  • 1965 - 1973 Classic Mustangs -General/Talk-
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rpms

  • Thread starter Thread starter Alarus
  • Start date Start date Aug 26, 2005

Alarus

New Member
Apr 29, 2005
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Az
Aug 26, 2005
#1
  • Aug 26, 2005
  • #1
what would a good red line for a 73 302 be, installed a tach and now i just wanna move the needle to were a good redline is, dont think its 4k.
 

krash kendall

Active Member
Nov 19, 2004
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Aldergrove, B.C. Canada
Aug 26, 2005
#2
  • Aug 26, 2005
  • #2
I keep mine below 4500 RPM, just for the cost of gas.
 

Alarus

New Member
Apr 29, 2005
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Az
Aug 26, 2005
#3
  • Aug 26, 2005
  • #3
cruzing i try to keep it at 2-2.5k witch keeps me at about 60-65 mph i just wanna know what the redline is so i dont hurt the poor little engine if i ever decide to play
 

krash kendall

Active Member
Nov 19, 2004
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36
Aldergrove, B.C. Canada
Aug 26, 2005
#4
  • Aug 26, 2005
  • #4
Wow that's low. At highway speeds I'm around 3800 with the C4 and 3.50 gears. A 302 will easily stand up to 4500 and with some work can get up to 6500.
 

12sec67

Active Member
Oct 6, 2003
1,301
1
36
San Diego, Ca
Aug 26, 2005
#5
  • Aug 26, 2005
  • #5
stock 302... 2 or 4 barrel?
 

Max Power

Active Member
Jul 31, 2003
1,774
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36
St Paul
Aug 26, 2005
#6
  • Aug 26, 2005
  • #6
Tough question to answer without knowing anything about your engine...
 

coolblue65

Founding Member
Jul 26, 1999
1,224
2
39
Algonquin, IL
Aug 26, 2005
#7
  • Aug 26, 2005
  • #7
If it is bascially stock your redline is probably between 5200-5500. Back when I first got mine it would start breaking up around 5500.

Are you running points in your distributer?
 

Alarus

New Member
Apr 29, 2005
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Az
Aug 26, 2005
#8
  • Aug 26, 2005
  • #8
car is a 73 coupe, 302, Points, 4bbl carter, and a performer manifold, and a c-4 tranny other than that its compleatly stock (as far as i know)
How can i tell what rear end gears i have?
 

12sec67

Active Member
Oct 6, 2003
1,301
1
36
San Diego, Ca
Aug 26, 2005
#9
  • Aug 26, 2005
  • #9
what is you rpm at 65... so we can give a rough estimate or you can crawl under your car and look at the tag on the rear end being held on by the bolts.
 

Alarus

New Member
Apr 29, 2005
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Az
Aug 26, 2005
#10
  • Aug 26, 2005
  • #10
rpm at 65 is 2.5-2.6k
 

Alarus

New Member
Apr 29, 2005
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Az
Aug 26, 2005
#11
  • Aug 26, 2005
  • #11
it looks like the p/o had rearend work done on it, theres silicone on it and it dosnt look no 32 years old...and i couldnt find a tag when i got under it.
 

Max Power

Active Member
Jul 31, 2003
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St Paul
Aug 26, 2005
#12
  • Aug 26, 2005
  • #12
With a stock valvetrain, you will probably be getting valve float at about 5000 rpms.
 

mudbilly

Member
Jun 3, 2005
175
0
16
South County, Maryland
Aug 29, 2005
#13
  • Aug 29, 2005
  • #13
Alarus said:
rpm at 65 is 2.5-2.6k
Click to expand...

if you have standard diameter tires (about 25 inch), you have a 3:0 rear
 

mudbilly

Member
Jun 3, 2005
175
0
16
South County, Maryland
Aug 29, 2005
#14
  • Aug 29, 2005
  • #14
red line question

i've always wondered.........

what determined the factory red line rpm on these cars?????????

did the valves start to float??? did they figger that if you went 500 rpm over the redline the engine blows up????

fwiw, i just looked at the factory tach wainting for install.....and there is no redline indicated.....go figger

http://www.picturetrail.com/gallery/view?p=999&gid=8253932&uid=3200195&members=1
 

MustangMatt1966

New Member
Mar 11, 2004
1,004
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0
Orlando Fl.
Aug 29, 2005
#15
  • Aug 29, 2005
  • #15
mudbilly said:
i've always wondered.........

what determined the factory red line rpm on these cars?????????


haha they take it out, and beat the crap out of it till it wont go faster!
Click to expand...
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Aug 29, 2005
#16
  • Aug 29, 2005
  • #16
Lets put it this way: you'll float the valves well before you reach the rpm limits of the bottom end. And that's IF it will rev to the point where it would float the valves ( this is all assuming it's still got the stock cam and valvetrain) Stock 302 bottom ends will survive occasional burst's to 6500 rpm's.( again, this is also assuming that the crankcase isn't sludged up and the oil pump is in good shape)
 

Max Power

Active Member
Jul 31, 2003
1,774
1
36
St Paul
Aug 29, 2005
#17
  • Aug 29, 2005
  • #17
Usually lifter pump up and oscillating valve springs that are to weak to run higher will cause the float.

It's a natural rev limiter, and softer valve springs reduce friction and help cams and keepers last longer. That's a big deal if you are offereng your customers a warranty.

I also imagine that stock 302 exhaust port flow numbers have a little to do with it.
 
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