Thread: 305 chevy

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i have a 305 chevy and was considering a cam swap. would a cam with:
292/292 duration
480/480 lift
230/230 duration @ .050"
109 lobe separation
be to much for my 305 chevy for daily driving. i would also be instaling new valves, springs, roller rockers, intake, carb, torque conveter 2000-2300 stall speed, and shift kit.

Well I had my 305 bored .060 and put in a 218/224. .050 cam and wouldn't want any more than that. With a 230.050 dur. it will idle like crap. What intake and carb are you using?

i havent bought it yet but im planing on a edelbrock performer intake and a holley 600 cfm carb(roughly)

Thats what I have on mine. You might get away with a slightly bigger cam that what I'm running, but 230 is to big for a stock bore 305. Corse thats just my opion and others more knowledgeble might have different ideas. Those 305 are pretty good motors and if you can match everything up for that motor and not use to much, you've got yourself a solid little runner. I'm running 304HP and 313 lbs. of torque and thats after running 3 different carbs, intakes, cams, etc. I finally found the performer intake and 600 cfm cam worked best with my cam. I'd run alot better if I had better heads, but I just ported my stock heads and they worked fine. Good luck with your build!

I'm running a .454 int/ex - 290 int/ex and it is very streetable.
( 78 firebird with 305 )

Here's Crane's description of a 230 degree cam in a small block. If this describes your motor and your intentions, go for it, otherwise follow Chevy 37's advice. He has "been there, done that".

PERFORMANCE USAGE, GOOD MID AND UPPER RPM HP, BRACKET RACING; STREET, HEAVY, ETC., AUTO TRANS W/3000+ CONVERTER, 10.0 TO 11.5 COMPRESSION RATIO ADVISED. BASIC RPM 3200-6200

Take note that you'll need at least 10.0:1 static compression ratio to make the 230 cam work due to the delayed intake closing point.

Originally posted by techinspector1
Here's Crane's description of a 230 degree cam in a small block. If this describes your motor and your intentions, go for it, otherwise follow Chevy 37's advice. He has "been there, done that".

PERFORMANCE USAGE, GOOD MID AND UPPER RPM HP, BRACKET RACING; STREET, HEAVY, ETC., AUTO TRANS W/3000+ CONVERTER, 10.0 TO 11.5 COMPRESSION RATIO ADVISED. BASIC RPM 3200-6200

Take note that you'll need at least 10.0:1 static compression ratio to make the 230 cam work due to the delayed intake closing point.

Cranes description of that cam would most likely be in a 350...in a 305 it would be more radical.
With a 305...or any small bore engine, always error to the small size. a 305 is very easy to over cam, & over carb. They arent as forgiving as larger bore engine....like a 302 for example.

If you are talking about the CompCams Magnum 280 which is .480 lift and 230 degrees duration @ .050, that is way too big. I run that cam in my 383, and I would not want anything bigger for the street. Call CompCams or Crane's tech line, and ask for a recommendation. Have all your specs in front of you. I think you will find that they will put you in the range 37 Chevy is talking about.

I built the crap out of my 305......400 crank etc......the biggest cam i would run would be a 270 magnum grind, reason being the small bore. you dont wat to run a cam bigger than that cause it will not be able to use it, the motor will not likely respond well with it at all. my specs are 221@.050....465" lift 108LSA..It has a wicked idle if thats what you are looking for. My heads have been fully ported and polished, torker intake and a 600 holley. Im not sure what else it has left in it without spraying it, but it makes close to 400 at the flywheel. Cam selection can make or hurt the motor and 230 @050 is way too much for the bore....unless you are running a blower i would'nt use a cam that big, it does'nt need it and it won't like it. If a lumpy idle is what you are after have a cam ground with less than 110 degrees LSA.

other mods are: 1 5/8" hooker supercomps, th400 3000 tcs stall, auburn posi, 3.73:1's 275 60 15's........lots to consider when building a motor for the street or even the track, throttle response is one of the keys. also with this cam i have to run a vacuum canister for my power brakes. the motor seems to have awesome throttle response and does not bog or stumble at all.