Old FMS A460 intake vs new TFS

I'm looking to see how much HP I'd be leaving on the table by not upgrading my current Motorsport A460 intake to the new style TFS intake. Combo is:

572 11:1
Early A460 heads ported 2.3 valves 415ish cfm
Large roller cam 270/290ish 800ish 108ls
Pro systems carb
2 1/8 headers, 3.5" exhaust

Will be in a 4000lbs truck with a c6 and 3.70 gears. Also have a IS real street kit as well.

IMO until you get the heads working better the old intake is the best choice.

Those numbers aren't any good? Hoping this motor makes over 800hp. Looking to go pretty fast on pump gas.

tfsbbf466 wrote:Those numbers aren't any good? Hoping this motor makes over 800hp. Looking to go pretty fast on pump gas.

If that engine does not make over 800 horsepower you have other issues beside the intake manifold.

The newer TFS intake will be better above 6,500 RPM and the older FMS intake better below that 6,500 RPM.

tfsbbf466 wrote:Those numbers aren't any good? Hoping this motor makes over 800hp. Looking to go pretty fast on pump gas.

It should make 800hp, all I'm saying is those heads are nowhere near where the current heads are at for flow and power

414 cfm can be easily had with P51 on other similar smaller heads nowadays.

That's going to be one fast street truck! I would like to know more about the truck, and how it is set up to handle that torque. I would also like to know more specifically how you are going to use it. Living vicariously through the internet, I suppose.

The cam made peak power @6900-7000 in an A head 557. So 15 more cubes may lower the peak down. Sounds like the intake is going to be fine.

My truck is pretty basic. 73 shortbed lowered Caltracs. Im hoping it runs well with the new combo. My old TFS street 512 dipped into the 9s once on spray but now the cast crank is laying in the oil pan lol.

You've definitely got more HP left in the heads. I'm making right at 1000 hp with the old FMS intake with a 588. I'm at about 14:1 on compression. I have 2.300 Intake and 1.880 Exhaust valves. 2-1/4" headers to 4" collectors.