Team Chevelle banner
  • Hey everyone! Enter your ride HERE to be a part JULY's Ride of the Month Challenge!
1 - 18 of 18 Posts

·
Registered
Joined
·
60 Posts
I have heard conflicting information on the red line on the 1970 396 SS .
One individual said all big blocks red lined at 6500 while another said it red lined at 5500 and only the small block red lined at 6500.
My 1970 396 L89 red lines at 5500 the sticker includes the option of special instrumentation purchase?

Thanks for information regarding this question in advance
 

·
Registered
Joined
·
295 Posts
Randy. As far as I know the 396/350hp. and the 454/360hp. factory tachs. red lined at 5500rpm. The 396/375hp. and the 454/450hp. were at 6500rpm. Believe the L89 would have been 6500rpm. also. Dont believe an ElCamino would be different.
 

·
Premium Member
Joined
·
3,595 Posts
BBC hydraulic lifter cars/ 5500, solid lifter cars 6500. Small block 71-72 5,000.
 

·
Premium Member
Joined
·
19,967 Posts
1. The 307 and two 350 engines tachometers redline at 5000 RPM (broadcast code 938).
2. The 402/330 (LS3), 396/350 (L34) and 454/360 (LS5) engines tachometers redline at 5500 RPM. * (broadcast code 985)
3. The high performance 396 (L78) and 454 (LS6) redline at 6500 RPM. (broadcast code 983)
* To date, all documentation shows that the Atlanta plant installed the 5000 RPM redline tach in all base SS454 Chevelles through at least late April. It is assumed this was a computer programming error that generated the code for the 5000 RPM tachometer instead of the 5500 RPM unit. This appears to have been 'fixed' by at least 05-05. The code for the 3 different tachometers can be found in block #72 of the build sheet; 938 for the 5000 RPM redline, 985 for the 5500 RPM redline, and 983 for the 6500 RPM redline.

1970 Chevelle SS396/SS454
 

·
Registered
Joined
·
60 Posts
Discussion Starter · #6 ·
Thanks for the information. After reading the information on the last post about the instrumentation choices it is some what confusing. This vehicle was a solid lifter cam with a th400 trans. Has all the proper guages for SS equipment the sticker included the u14 code for that option. Still confused as to 5500 red line? It is what it is?
 

·
Premium Member
Joined
·
1,574 Posts
It is not that confusing. If your car came from the factory with an L78 396 it should have a 6500 rpm tach in the dash.
 

·
Registered
Joined
·
10,465 Posts
It is not that confusing. If your car came from the factory with an L78 396 it should have a 6500 rpm tach in the dash.
Tachs are easy to change. When I bought my 71 El Camino the factory tach didn't work. Before I sent it off to be repaired I found one sitting on the shelf of a local junkyard. I didn't care what the redline was, just that it was 1/3 the price of having the original fixed. It doesn't really matter what's in it now as long as his documentation is legitimate, he can always source the correct tach.

Steve R
 

·
Premium Member
Joined
·
1,574 Posts
I think he wanted to know what his car should have in it that is why I responded. I'm sure it could have been changed at some point. As I already said an L78 car should have a 6500 rpm tach.
 

·
Registered
Joined
·
338 Posts
And from what I gathered because the L78 and LS6 revved to 6500, they couldn't be ordered with air conditioning because they spun the condenser too fast.
How 'Merican is that?
 

·
Registered
Joined
·
60 Posts
Discussion Starter · #11 ·
Could it have been possible? Since there was a strike in 69 and this vehicle had a November 69 build date they ran out of 6500 they stuck a 5500 in there ?
 

·
Registered
Joined
·
8,147 Posts
Could it have been possible? Since there was a strike in 69 and this vehicle had a November 69 build date they ran out of 6500 they stuck a 5500 in there ?
No that's not how a assembly line works. When a order was received and processed all parts was scheduled and ordered from all vendors.
 

·
Registered
Joined
·
10,465 Posts
Could it have been possible? Since there was a strike in 69 and this vehicle had a November 69 build date they ran out of 6500 they stuck a 5500 in there ?
It's possible, but not likely. Source the correct tach. It's not worth the gymnastics you will need to go through trying to justify the incorrect part just because it's there now. If you had a build sheet that showed the installation of a 5,500 rpm redline tach that would be a different story, if not, any explanation will come across as a song and dance. It will draw attention away from the car being an L78/L89, so what's the point of keeping it in place.

Steve R
 

·
Registered
Joined
·
8,147 Posts
does your tach have a date ink stamp on the back?
 

·
Premium Member
Joined
·
3,900 Posts
6500
 

Attachments

1 - 18 of 18 Posts
Top