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

How to break in new shortblock/cam?

  • Thread starter Thread starter fox racer
  • Start date Start date Dec 31, 2006

fox racer

Member
Jun 22, 2004
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16
Staten Island, NYC
Dec 31, 2006
#1
  • Dec 31, 2006
  • #1
I finally ordered some parts and I'm getting ready to take out my old motor. I'm most likely getting a low mileage 302 or a fresh rebuild (no more money dammit). Id rather get a cheap shortblock, do the supporting stuff so the car runs (Jet Hot the LTs, new cam, etc...). Then maybe I'll save for a 331 that I want. But for now, I need my car running. My question, how should I go about breaking the cam/shortblock in? or should I just take it easy for like 500 miles?
 

RYC CUKR

Founding Member
May 19, 2002
1,437
1
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51
Orlando
Dec 31, 2006
#2
  • Dec 31, 2006
  • #2
Roller cams need no break in period.

For a fresh short block I would do the same that I would do for a new car. Drive it normally for the first 500 miles or so, read don't beat on it right off the bat. Also make sure that you vary the RPMs during the short block break in. Change the oil and you are ready to go. This is how I have always broken in new cars and new engines and I have never had a problem.
 

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
38
Miami, Ok
Dec 31, 2006
#3
  • Dec 31, 2006
  • #3
way i do it. start the car, bring the rpms up to around 1500 and hold it there, let the engine warm up to temp and inspect for leaks. when its warmed up and if its all good. take it for a drive and go in 2nd and gun it from like 25 to 50 and stay an gear and let the car decelerate in gear, the rpms and vaccum will keep the engine well oiled and seat the rings, just do that like 10 times and park it and change oil and then drive normally for 500 miles, but stay away from a constant speed and rpm, like dont cruise at 55 for like 20 mins, try to vary the rpms. then after the 500 mile oil change, drive it pretty much normally until 2k miles and change the oil again and if no problems its good to go. worked for me

dont be afraid to give it some gas and drive it like you would normally. dont beat on it more than u normally would and dont baby it. if something is going to break, its going to do it within the first few mins of start up
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
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129
New York
Dec 31, 2006
#4
  • Dec 31, 2006
  • #4
Driving it easy for 500 miles is the wrong way!

Get it warmed up and ready to go, take it out and do a few 2nd and 3rd gear 1/2-3/4 throttle blasts to like 5k rpm or so and let it decel IN gear. Do this a few times varying the speed, rpm and gear then come home and change the oil. You are now broken in, now go drive it however you want.
 

fox-gt

Member
Feb 28, 2004
204
0
17
TN
Dec 31, 2006
#5
  • Dec 31, 2006
  • #5
RYC CUKR said:
Roller cams need no break in period.

For a fresh short block I would do the same that I would do for a new car. Drive it normally for the first 500 miles or so, read don't beat on it right off the bat. Also make sure that you vary the RPMs during the short block break in. Change the oil and you are ready to go. This is how I have always broken in new cars and new engines and I have never had a problem.
Click to expand...

This is what I was told to do with mine also.
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
55
windsor, Canada
members.cardomain.com
Dec 31, 2006
#6
  • Dec 31, 2006
  • #6
Drive it like you paid for it....get anal with the gauges, keep the oil clean. I baby mine 95% of the time for the first 500 because it makes me feel good...though I like to tach her up to 5000-5500 in second and third once or twice every time out. My oil changes were 10 miles, 200 miles 500 miles and 1500 miles.
 

bubba-dough

Active Member
Dec 28, 2004
1,044
2
38
Indiana
Jan 1, 2007
#7
  • Jan 1, 2007
  • #7
Grn92LX said:
Driving it easy for 500 miles is the wrong way!

Get it warmed up and ready to go, take it out and do a few 2nd and 3rd gear 1/2-3/4 throttle blasts to like 5k rpm or so and let it decel IN gear. Do this a few times varying the speed, rpm and gear then come home and change the oil. You are now broken in, now go drive it however you want.
Click to expand...

+1 After the initial oil change after break-in, I like to change the oil and filter 2-3 times before 3000 miles.
 

90

Active Member
Sep 24, 2006
0
1
43
42
Michigan insane asylum
Jan 1, 2007
#8
  • Jan 1, 2007
  • #8
Drive it like you stole it!........... your in a high speed chase and your cars the fastest on the road... pay off all the tickets and when you get your license back, it should be broke in!
 
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