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Engine Break-in oil questions

  • Thread starter Thread starter Justin87
  • Start date Start date May 25, 2021

Justin87

5 Year Member
Aug 7, 2017
158
45
48
May 25, 2021
#1
  • May 25, 2021
  • #1
Hello all!

I think it’s about time I finally start my 90 GT that I did a motor and transmission swap on.

I would like some opinions on break-in oil.

What brands do you guys like?

After the initial start, setting timing and all that (assuming I can get it running ) how quickly should I change the initial break-in oil?

I’m under the impression that “first start” oil should be different than the first drive/actual engine break-in period, but I also am a rank amateur so who knows.‍

thanks for your time!

-Justin
 

HemiRick

I'd be looking at jacking under the house
Jun 28, 2020
723
272
73
Memphis TN
May 25, 2021
#2
  • May 25, 2021
  • #2
Break in oil is mainly needed for flat tappet cams....if your engine has a roller cam, it should, forget about break in oil and just run whatever oil you are going to run in it for life.
 
Reactions: 68keyblr, limp and 7991LXnSHO

stormsedge

5 Year Member
Jun 17, 2018
439
195
63
Here
May 26, 2021
#3
  • May 26, 2021
  • #3
HemiRick said:
forget about break in oil and just run whatever oil you are going to run in it
Click to expand...

^^I agree^^ There was a day (so many years ago) when a light non-detergent (10 or 20w) was common practice in new builds...I never did it, and the guys I knew building real racing engines never did it. Start with what you are going to run.
 
Reactions: 68keyblr

j753303

Active Member
Aug 25, 2020
73
28
28
MASS
May 26, 2021
#4
  • May 26, 2021
  • #4
as long as its not synthetic. i would wait at least 1000 miles for that.
 

Justin87

5 Year Member
Aug 7, 2017
158
45
48
Jun 1, 2021
#5
  • Jun 1, 2021
  • #5
Thanks guys.

got all my fluids sorted. Going for a first start this weekend!
 
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