What are my options for a low RPM (under 6500) torque producing intake manifold? This will be on a 416" L-92 block with Patriot stage III cathedral-port heads and 11.4 static CR that will not see 6500 and likely a 6000 limit. Cam is 233°/245° on a 110 LSA, headers with the usual mods. Would like to stay injected (Holley HP EFI) but could use 4 bbl throttle body if hood clearance permits...

 

Somehow I didn't figure to get a response, everybody here seems to be hung up on 8,000 RPM and 600 RWHP...

 

Some race cars have been known to use a truck intake manifold.

 

Truck intake likely makes the most torque but may be a huge choke point in the upper rpms. I'm not that familiar with them though. What's the goal of the car? I mean 6500 is very very conservative for these engines, and a FAST intake pulls to around there or a little higher.

 

My '63 Rambler American is light (maybe 2700 empty?) with a 325DR tire, 3.25 Ford 9" locker, and old-school 4 speed with 3.08 first gear. I want something that pulls hard from off-idle, strictly for fun on the street, no racing involved. I've got a sprung-hub clutch but still don't want to have to rev it to 4000 to take off from a stop. Hell, I'm old and have too much to lose getting caught f'ing up...

 

Have you considered a Edelbrock Performer RPM (dual plane) manifold, it'll offer better torque(an HP) below 4k then a FAST intake manifold.
The down side is that it loses power above 4k to the FAST intake.
Read this article:
http://www.superchevy.com/technical/...t/viewall.html

 

That was a good read, but there's a big difference (90 cubes) between a 5.3 and 416". I have run an engine sim program using the stock LS-6 vs a Victor, JR with a 1200CFM tb and the Vic blows the LS-6 away throughout the range. Not sure if the Performer would be a choke point under 6500 and I don't have a manifold file for that piece. I may need to use a stock-type manifold for hood clearance, would a FAST 102 be a choke on an engine this big?

 

Fast 102 should feed a 4xx engine nicely I would think.

 

I'm thinking that will be my "best" option, at least for everything but price. Oh well, it's only money...

 

They have a truck version of the fast102 also.

 

Thanks! I'll have to see where my hood clearance ends up. I will NOT cut this hood, it's as beautifully finished inside as out.