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Old 09-17-2018, 05:37 AM   #176
Terrick down Under
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Re: Fastfreddys 454ss

Well done, hard work has paid off!
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Old 10-14-2018, 08:54 AM   #177
68 TT
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Re: Fastfreddys 454ss

Lots of great ideas and research for mods to our trucks. Great work.

I wanted to add that putting the closed chamber 396 heads on would have been a mistake just to raise the compression. The valve size is no bigger and the flow of the heads isn't enough better to be worth the effort and expense of rebuilding them. The closed chamber 396 heads have a bad valve shrouding issue in stock valve size with higher lift cams and it becomes a severe hindrance to air flow if you put the 2.19 & 1.88 valves into them. The later model open chamber versions like the 049 casting flow substantially better and are the one to go with if you want a large oval port stock head on an engine.

That being said the peanut port heads on our TBI 454 engines have a whole lot more performance potential than most people give them credit for. Even with the stock valve size they flow enough air to make some pretty good power in naturally aspirated form on an engine with good compression, a decent sized cam and a good flowing top end and exhaust. These were all the reasons the heads have a poor reputation to begin with. The stock compression is pathetic, the cam is unbelievably tiny and the intake & exhaust systems choke down what little air could get to or out of the heads so heavily that they never had a prayer of making any decent power in a stock TBI 454. With your supercharger, better intake, bored out TBI and headers all you need is a cam with the correct profile to work right with boost and still be computer control friendly so it is tunable and you are good to go.
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