i recently bought all the bottom end componets for a 420 that i am working on building for my 3rd gen, i havent selected any top end or induction componets though, i have seen the kit from summit for trick flow's 500hp heads and cam, but i was wondering if any one haa has previous experience good or bad with tfs heads. also i have a corvettte tpi system, with larger runners and 58mm or ASM's mono blade throttle body will this system be able to flow enough to let my motor breath above 4000 r's, any experince with any of these will help thanks.this is my first engine build and i want to do it right the first time so here is what i have.

2 bolt 400, 2pc w/splayed 4 blt mains
4340 scat 3.875 w6.0 rods
je floating 10.5 forged pistons
decked to 9.0, .030 over

86 corvette MAF tpi

 

the stock maf is gonna hold you back. i would also suggest something along the lines of a miniram intake,just dont think you will be happy with the tpi.

you would be better off with some sort of aftermarket injection,dfi gen 6 can be bought fairly cheap,and has a lot more potential then the maf tpi system. at worst,look into a speed density tpi computer.

 

I would be very surprised to see any of the factory & also many aftermarket TPI components flow enough for a 420. The factory lower intake is not that big.

At this level you should consider a full EFI intake. (eg. Superram or converted carb intake) No use building an engine that revs like a diesel.

The Trickflows are decent but ideally designed for a 350 street engine. With that large of an engine, velocity of even the 210-220 cc intake ports will have good velocity. Check out World Products as they have some big cube small block kits that you could mimick.

 

Wow tons of head choices, and if you have the cash you can get some really nice stuff for cheap.

What do you want to do in terms of the valve train? What type of cam? That's going to limit you in terms of head choice, but I am thinking crazy stuff here.

The intake is a biggie, but that depends on the hood too. If you have the room the right intake is going to pull it all together.

Bret

 

I would swap out your intake to a Ram and 58 mm TB. Switch to a 730 ECM (90 to 92 Fbody) or a 727ECM (weather hardened version for Vette). This is a Speed density ECM so the MAF goes away. Retune and let her rip.

Steve

 

I'd swing to Lonnie's advice on the converted carb intake with a 4bbl throttle body.

The Dart Pro 1 230cc would be a nice choice as would similar Brodix and AFR heads. I would personally spring for maybe an 18X Brodix or an all out 14, 15 or 18º head. Money is the biggie here... but when isn't it.

-Mindgame