1970 LS5 Cam

[Robert H]

I have a 1970 Convertible, 4-speed, 454 (390 HP LS5), and I want to return to the stock cam. I have been looking around the net, and have become confused, as there seems to be differing beliefs on what that cam is. The numbers that show up most often for the 1970 LS5 are GM3883986 with 214/218 deg dur @ .05', .461/.480 lift,114 or 115 deg L/S angle. However, I have also seen GM3874872 244/284 @.008", .398"/.430" claimed as the correct part for this car. Another data point is Zip Corvette--they claim their cam "EN150" is correct stock spec for the 70-74 Corvette 454, and it is 193/204 @.050, and .440/.440 lift. I also notice that they sell their "EN-149" cam for 67-69 390-400HP which is about the same spec as the GM3883986--that is 214/218 @.050, .461/.480 lift. Also note that this is essentially identical specs to Crane #969391 from summit: 214/218 @ .050, .461/.480 lobe sep 115, “grind number”= 3883986. Can anyone shed some light on what is the correct stock specs for the 1970 LS5??

[iburke]

Good question. I will see if I have any info on that. The 2 cams you mention sound like the diff between the 425 hp LS6 with aluminum heads and the 365 hp LS5 with iron heads. The two also had diff carbs and manifolds.

I believe that the LS6 was also a solid lifter cam.