1971 Intake Manifold
Thread Starter
Heel & Toe
Joined: Feb 2013
Posts: 20
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1971 Intake Manifold
Hello, I own an early 71 LS5 purchased with modified LS6 after market intake manifold. Does anyone know if the early (June-Aug 70 date code) manifolds listed the cylinder sequence numbers on it? I want to make sure Im searching for the right manifold as I've heard they may have introduced the numbers on late (after #4000) 71's.
Thank you,
YDubbs
Thank you,
YDubbs
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
My NCRS Specifications Guide lists 3955287 cast iron for the 71 LS5s. Dates can get screwy. A strike began about 9/15/70 and did not end until very close to Thanksgiving. It is possible cars slated for production at or near the beginning of the strike (engines would have already been at St. Louis) can end up with November or December time/build dates.
Thread Starter
Heel & Toe
Joined: Feb 2013
Posts: 20
Likes: 0
How far back should I look for right date code? Would it have been feasible that a February 70 manifold would've been installed on a Sept built motor? My vette didn't roll of assembly line till late Nov. the strike explains delay.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
What is the engine assembly date for your car? The original intake would have been on the engine when it was assembled and subsequently shipped to St. Louis.
My fiancee's 71 convertible is a strike car. Assembly and casting dates all point to a probable mid-September assembly date. Due to the strike, the time/build date is December 1.
My fiancee's 71 convertible is a strike car. Assembly and casting dates all point to a probable mid-September assembly date. Due to the strike, the time/build date is December 1.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
The NCRS allows up to six months on date codes. In the real world, dates were closer, especially on engines. The intake manifold cannot be older than the engine assembly date. If your engine was assembled in early September, 3-4 weeks before the engine assembly date would be good; two weeks even better.
Good luck with the hunt.
Good luck with the hunt.
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