408 cam help

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Challngd73

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Hey guys, I bought a ATK 408 forged shortblock for my 66 cuda.
current plans for it this year, are to use some spare parts I have laying around, and put a decent cam in it. I have a set of 340 J-heads that I hope will suffice until I put some better heads on it next summer. I am looking at voodoo series lunati 268 hydraulic flat tappet cam. Any thoughts on that for a street cruiser in a 408?
 
that would be helpful. 3.55 gears, 904 transmission, looking at 2400 rpm tq converter. Rear tires, not sure of height, 18x9.5 with low profiles, maybe 27.5-28 inch tall tires.
 
I ran that cam in my 416 when i first built it very impressive results with 3.91's and 3800 stall converter..:D:D
 
268 or 276 should be a good choice on the street with what you have. Did you figure out where you would be on compression with that set up ? That would help in making the final choice for me.
 
Well, Im not sure what cc is on the 340 J head. 62cc would be 10.2:1, 68 cc=9.6:1, 72cc=9.3:1
 
I had the comp version of the 268 in my 360 and It ran very well. But I changed that out for a lunati solid roller cam now.

I know they are more expensive but since you have to buy a new cam anyways would you consider a roller cam? Just so many more positives. Only reason I am saying this is because my old flat tappet cam was going flat...
 
DartVadar said:
I had the comp version of the 268 in my 360 and It ran very well. But I changed that out for a lunati solid roller cam now.

I know they are more expensive but since you have to buy a new cam anyways would you consider a roller cam? Just so many more positives. Only reason I am saying this is because my old flat tappet cam was going flat...
Click to expand...

I have thought about going roller, just dont know if I can justify the added cost right now.
 
Challngd73 said:
I have thought about going roller, just dont know if I can justify the added cost right now.
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Thats understandable. Flat tappet cams are fine, you just have to make sure you use the right oils and break the cam in correctly.
 
DartVadar said:
I had the comp version of the 268 in my 360 and It ran very well. But I changed that out for a lunati solid roller cam now.

I know they are more expensive but since you have to buy a new cam anyways would you consider a roller cam? Just so many more positives. Only reason I am saying this is because my old flat tappet cam was going flat...
Click to expand...

Was it the Comp cam that was going flat??..
 
stroked340 said:
Was it the Comp cam that was going flat??..
Click to expand...

Yes it was. The motor had to come out for an unrelated issue, as I was taking the motor apart I looked at the cam and some of the lobes had some really weird wear on them, the nose on 2 of the lobes was showing noticeable wear, and measuring confirmed this. The engine had about 3k miles on it, that cam wasn't going back in so put in the lunati solid roller. I correctly broke in the cam and used a zinc additive in the oil, but I was lucky that it didn't go completely flat.
 
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