408 heads?
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11 Second Club
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From: Frederick, Maryland
408 heads? I currently have a set of AFR 230 heads on my 347 LS1. They are 64cc chambers and currently are setup for a solid roller cam. The cam is a 248/254 .673/.673 w/ 113+3 LSA. The heads have PAC 1207 springs, Yella Terra 1.7 adjustable rockers, Comp solid lifters, and Manton pusrods. Will these head and cam setup work on a 4.03 bored by 4" stroke 408 motor? I currently spray about 400 to 450 of nitrous in the 347 and am looking to bump up to about 500 to 700 in the 408. Will this work? Thank you.
That's a lot of ******* sauce...
The 64cc chambers is going to drive your compression thru the roof on the 408. With that much nitrous, I would look into getting a head with a larger chamber, and a cam that has more overlap to bleed off some cylinder pressure to avoid using a dished piston.
Now, take that for what it is worth as I'm not that experienced with that much nitrous, but I believe a piston with less of a dish Is better to keep the flame front moving better.
Someone please correct me if I am wrong.
The 64cc chambers is going to drive your compression thru the roof on the 408. With that much nitrous, I would look into getting a head with a larger chamber, and a cam that has more overlap to bleed off some cylinder pressure to avoid using a dished piston.
Now, take that for what it is worth as I'm not that experienced with that much nitrous, but I believe a piston with less of a dish Is better to keep the flame front moving better.
Someone please correct me if I am wrong.
Thread Starter
11 Second Club
iTrader: (98)
Joined: Aug 2007
Posts: 453
Likes: 0
From: Frederick, Maryland
I contacted Diamond and they spec'ed me out a custom set of nitrous pistons that will be 0cc flat tops. With a .040 head gasket the compression will be around 12.5:1 and that is perfect. I just am not sure if the heads will be providing enough CFM. I use a Vic Jr that is port matched to the heads and a single plane throttle body. This motor is going in a drag only car, I am not worried about streetability. I will be using C16 fuel so I like the higher compression. I already talked to Tony Mamo and he said the heads will work on the 408. I am thinking about going bigger with the cam tho.
