450hp big block

canadianchevy33 · September 13, 2004

The engine is a stock 1989 454 Im not sure of the stock compression on it Does anyone else know? The parts to be added to this are...

Stock or mildly ported oval port heads

Performer rpm intake

750 or 850 cfm demon carb

[email protected] 0.530-50 lift

1.7:1 roller rockers

1 3/4 or 1 7/8 long tube headers

3 inch true dual exhaust with magnaflow mufflers

Will this combination yield me around 450 horsepower? Any ideas what the compression would be? Would the engine still be able to take a 100 shot of nitrous? Thanks

o4yukonxl · September 14, 2004

This does not sound like a 450HP recipe. The weakest link in any engine is the cylinder heads and the stock 454 heads are very restrictive. All you other mods won't work unless your really open up the heads. Get some good aluminum heads even if you have to cut corners on other items. You can make 450HP with 9.1 to 1 with the right parts.

Metz Motorsports · September 14, 2004

A simple list of parts will make 450hp very easy with a big block chevy. Some decent aftermarket heads, aluminum or not, and a nice roller cam (relatively small one at that) should do the job. With those type's of parts comes others though, as in a carb and nice flowing intake to match the new heads and cam. The bottom end of a 454 is stout enought to run stock parts (i.e. crank, rods, etc.) to a certain point. The first 454 I 'built' consisted of stock bottom end parts except pistons (some domed pistons were used), a .590ish lift hydraulic roller cam (240° @.050 duration if memory serves me well) and a set of Edlebrock Performer RPM heads and holley 750. This made 563 hp at the crank. NOS says that a stock big block can hande up to something like a 200 shot with no problem providing the proper set up. Hope this helps.

-Jason

canadianchevy33 · September 21, 2004

I have recently read that 96 and up L29 vortec semi open chamber heads are better then any 60's closed or open chamber head the only downfall to them is the smaller 1.72 exhaust valve. Anything I would have to change to use these heads other then switching to an adjustable valvetrain?