LS Swap and the CA DMV

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Joe Brown

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California
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Joe
Truck Year
1973
Truck Model
K5 Blazer
Engine Size
350
If you do an LS swap on pre-smog truck (like our 1973), will it still be exempt from CA smog?

(California’s laws are a little Byzantine, and google doesn’t seem to have any answers on this.)
 

DoubleDingo

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Carb'ed Vortec 350; 1972 L48 350
Just don't tell them what engine is in it. It's a 73, register it as a 73
 

skysurfer

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California says the vehicle is tested according to the year of the engine, but that only works one way. A newer engine means newer standards, but you can’t install an older engine and be tested by older standards.

In your case, a ‘73 is exempt so nobody will ever look under the hood unless you do something stupid like telling the DMV about the swap.
 

swilson143

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You're smog exempt. You can swap motors and tell the world and there's nothing DMV can do about it.
 

Bextreme04

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You're smog exempt. You can swap motors and tell the world and there's nothing DMV can do about it.

Not necessarily true... He's exempt from biannual smog testing. That does not make the vehicle exempt from smog laws, so if someone reports it or the cops write him a ticket that requires a referee to inspect the vehicle, there could be an issue.

In practice you aren't likely to have that happen unless you are driving around being a jackass.
 

JBswth

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James
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1973
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C25
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292 cubic inches
Not necessarily true... He's exempt from biannual smog testing. That does not make the vehicle exempt from smog laws, so if someone reports it or the cops write him a ticket that requires a referee to inspect the vehicle, there could be an issue.

In practice you aren't likely to have that happen unless you are driving around being a *******.
If his rings are gone, he could be sited, but I don't think they can anything to him otherwise. Its a 73.
 

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