Manifold 454

[Harold #43147]

I have a 70 roadster with factory Alu manifold books I have say it is suppose to be cast iron????
Thanks

[Richard W.]

Re: Manifold 454

Harold: Yes, cast iron 454 intake only for 1970.
Rick

[Harold #43147]

454 Manifold

I found correct Cast Iron Manifold On Ebay Date is good to. The Books say the Alu. one is for 68-69 427 390 HP there is no date code so I guess it could be correct for both. Have a set of heads to match all's I need is a block and couple hundred other things and I would have a 69 427.
Thanks for the help Rick

[Richard W.]

Re: 454 Manifold

Harold, There are different casting numbers for the 390HP manifolds for 68 and 69. I believe 68 is 3919849 and 69 is 3947801. There should also be a casting date; a letter for the month, one or two numbers for the day of the month, and a number for the year. I wish they had used those aluminum jobs in 1970.
Rick

[Mark #28455]

don't pay too much!

The 1970 cast iron intake was used on all the oval port big blocks including the low perf 402's. Many hot rodders and machine shops (and old junkyards) have them. A good price would be $25 to $50. Shipping alone would be $25, so be aware.

[Harold #43147]

454 Manifold

Rick it is the 3947801 I can't find a Date Code on it I read in one of the books I don't know which one off hand but dais there was no Date Code on this manifold????
Thanks Harold

[Richard W.]

Re: 454 Manifold

Harold, I checked in my book and it said that unlike the cast iron manifolds that have the casting date on top in front of where the coil mounts, the aluminum manifold casting date is on the bottom. I'm not familiar with the aluminum manifold...is there an oil shield rivited on the underside? The date might be under there if so.
Rick

[Richard W.]

Re: 454 Manifold

Harold, By the way, my 70 is a 454 4-speed, Bronze coupe. Very early June build.
Rick

[Harold #43147]

Manifold

Rick I looked on the bottom a couple of years back when I re did the engine and did not see a date code.It does have a oil shield on the bottom which I R$R it to bead blast the carbon but never thought to look when I did it to see if Date code was under there but It's Probably there. I have it on the shelf when I put the shield back on I drilled and taped the holes for screws rather than rivets I will pull it off this weekend and will let you know it will be something for the memory bank.

Harold

[Joe L.]

Re: Manifold

Harold-----

On the 68-69 aluminum big block manifolds, the date is found under the oil heat shield. The shield has to be removed to view it. The shield is retained by special drive pins with serrated shanks. They can be removed by carefully prying them out. For re-installation I recommend drilling and tapping the holes for machine screws. This is especially important for aluminum manifolds. In any event, use new drive pins with Lock-Tite---you don't want these things falling out.

The date really means nothing, though. It can't be seen for judging, of course. Also, even if you found one with a 1970 date, that doesn't mean that it was original to the car. These manifolds were made for SERVICE well after 1969, so there are examples out there with dates which might seem to be "correct" for a 1970 or later Corvette.

1970 Corvettes with LS-5 used the cast iron manifold. Incidentally, during the 68-69 period, there were THREE successive, different aluminum manifolds used for Corvettes with L-36. However, aside from the casting numbers, you'd be hard-pressed to discern any other difference between them.