What can i add to my 305 V8 for more horsepower?

Answer 1

Look for performance parts that are usually listed as being for 305/350 truck engines. First thing I would do is upgrade the exhaust system - headers, hi flo cat,and a cat back exhaust.Stock headers (exhaust manifolds) are terrible.

Second upgrade the intake/air flow/fuel system.Stock breather assembly is terrible, and a "cold air kit" is a good idea. Hi flow throttle body (if fuel injected) which can be had from Holley or upgrade your stock one (CFM technologies & Turbo City). On Carburated engines - Holley makes good carbs. Intake manifold - dual plane from holley, edelbrock or GM perf parts for either FI or carb'ed engines.

Stock fuel pressure (FI cars) is poor so upgrade the stock fuel pump.An adjustable fuel pressure regulator is a good idea - necessary after some point, the more mods you do and bigger injectors are the same way.

After those things - camshaft and cylinder heads are the next area to look at.Stay moderate on the cam "size" (lift) - "big cam" is not always best. Edelbrock makes a good one for street use.

GM Vortec heads are the cheapest "performance " heads but the combustion chamber size - 64cc -will kill the compresssionon a 305.Vortecs like compression in the 9.4 to 9.8 range. Mill the heads to about 58cc using stock 305 "dished" pistons - 60cc or so with flat top pistons.

. Don't forget a lower (higher number) gear in the rear end.You probably should do some mods to the transmission (auto) if you want it to survive.Mucho Info is available on 3rd gen.org, Chevy Hi performane,Hi tech performance,Hi perf - truck web sites.Start googling and read, read, read.On a FI 305 - 265/280 HP is about what you'll get without spending a LOT of $$ - and if staying emisions legal.

300 HP and up?Then the best idea is to go up to a 350.Most of the parts you use on a 305 can be used on a 350. Some 305 engines have been made to make 400HP (carb not FI) and more.But the cost is usually way high and they are not emissions legal.Maybe not a good street engine at that level of HP.Lot of people "look down" on the 305 - I say if you've all ready got a good 305 - use it. They can be good performers for not a whole lot of cash.Even cheaper if you can do your own work.Learn and read - lot of info available - not all good - but most of it is.