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Oil burning on my recently buil 302

  • Thread starter Thread starter The blk67
  • Start date Start date May 15, 2026
T

The blk67

New Member
Jun 7, 2025
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Lansdowne, Ontario, Canada
May 15, 2026
#1
  • May 15, 2026
  • #1
Hi guys, I am having an oil burning issue with a recent rebuild in my car.
302, gt40 3 bar heads, 5 angle valve job, x303 cam, 1.6 roller rockers,
Gt40 tubular intake, with 1inch spacer and rebuilt stockbottom end.
As engine idles, there's no signs of blue smoke, the moment I start to drive it will smoke as I up shif, once cruising it stops the blue smoke, as I deceleration or gear down blue smoke, I need some help with this issue
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
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Claremore, OK
May 15, 2026
#2
  • May 15, 2026
  • #2
Did the machine show home the cylinders correctly? I had this happen once and had to tear the motor back down and the cylinders were not finished honed. Could also be a poor ring selection or installation. Best way to tell this is to do a leak down test.
 
Reactions: Mcmahst and Noobz347

Blackhawkxx

Mustang Master
Mar 3, 2023
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May 15, 2026
#3
  • May 15, 2026
  • #3
Valve seals will also act like this. If they were replaced there is still a slight chance that one or more was damaged with the install.
 
Reactions: Noobz347

Noobz347

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May 15, 2026
#4
  • May 15, 2026
  • #4
How many miles are on these heads?
Were they also rebuilt?

It sounds to me like no matter what it is, you're going to have to pull the intake and heads and explore until you find the issue.

I saw that somebody already suggested a leak-down test. That's a good place to start.
 
Reactions: General karthief and Mcmahst
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