hey guys i just finished a v6 to v8 swap and i went to a 305 (eventally going to a 350) and im already bored of the low power lol i have these performance mods so far:
headers
weiand intake
holley carb
dual exhaust
TH350 transmission with 3:73 rear gears

heres what im thinking of getting and all these parts will go on the 350 i put in sometime:
this cam unless you suggest a better one http://www.jegs.com/i/Comp-Cams/249/...oductId=963675

670 cfm holley throttle body injection
msd ignition and wires with E3 plugs


roller tip 1.6 rockers with higher lift springs
vortec heads
and ill port the heads too and get bigger valves, if i get vortecs should i get 305 or 350 vortecs? they will be getting ported with a valve job like i said

and the cam, thats the one that looks best to me so what do you guys think?

i will be getting all these parts on my 305 and then build the **** out of my 350 lol

 

If it were me, I would get a roller cam if that block is set for it.

As far as heads 305 heads can go on a 350 with no issue, but 350 heads can not go on a 305. It will screw up compression. I am not 100% on the specifics but I am sure somwone will chime in.

 

the block is a 1987 lo5 (i think thats what its called, but like i said i am changing heads with the cam) its not a roller now and i dont want roller cause the 350 block im going to build up isnt set for a roller, also can you port 305 vortecs to work as good as 350 vortecs? i thought the 305 heads would be better on a 350 if they were ported because of more compression

 

Well, how much power are you getting to the ground right now ?
And, what is your end goal for performance and drivability?

 

i dont really know how much power, the 305 has been babied its whole life with 105,000 miles and its completely stock exceot the mods i said, i want a weekend car and it will see the strip when i get my 350 in it, its just a fun toy that i want to be able to just spin around every corner i see lol and i know thats not very possible with the 305, im just buying the parts for my 350 pretty much, im just putting em on the 305 to get the most out of it while im building my 350

 

you can't use the Thumpr cam in a TBI 305. you shouldn't try it if you are carbureted. The Vortec 305 heads come in 2 versions, neither is better than LB9 081 heads. You can't put bigger intake valves in Vortec 350 heads if you want to run them on a 305, and there's really no point in putting the bigger intake valves in there anyway. I did this when I had unlimited use of a new SuperFlow 1020 flow bench with all the options.
For a cam for the 305, assuming you do switch to Vortec 350 heads, try this:
http://www.compcams.com/Cam_Specs/Ca...?csid=212&sb=2
That'll get you over 300 horses (at the crankshaft). It'll also work up to 6000 rpm in a Vortec-headed 305.

 

my engine isnt a roller now so doesnt that mean that i cant put a roller in it? and if those heads you said are better than i will get those, if i port those and get them machined and everything would they be good on a 350 someday? and i also have access to 416 heads

 

The 416s would be your better option for now. You'd be giving up some power, but you keep your compression.
I thought you had an '87 block, which has provisions for the roller lifters.
If not, that changes the cam suggestion.
If you use Vortecs now, you'll need them milled for compression, then to swap them to a 350, the 350 would then need dished pistons to compensate.
For Vortecs with a non-roller block, try this for a cam:
http://www.compcams.com/Cam_Specs/Ca...x?csid=95&sb=2
For non-roller with 416 heads, try this:
http://www.compcams.com/Cam_Specs/Ca...?csid=126&sb=2

 

This tells me very little, and I can't really gather all that much from your initial description of what you have right now.
What year is your 305? and what was it out of?
You make no mention of a distributor, so what are you running on it right now exactly?
It's not by chance a computer controlled distributor is it?

 

I just assumed an older, pre-computer dizzy. But if you're running the computer-controlled dizzy without everything the computer is expecting to "see", or if you're running it not even connected to the computer, then you'll have really poor results.

 

its an 87 non roller 305 with a HEI distributer, its also out of a truck, and if i get the 416s i am going to have them ported professionally and all that stuff, i basically just want parts that will liven up my 305 that i can just bolt on to a 350 later this year

 

but '87 blocks all have the provisions to accept rollers. That's the most important factor. Because used roller lifters from the salvage yard are usually cheaper than the cheapest new chinese non-rollers. And the power advantage, well, it's worthwhile to say the least. And no need for ZDDP additive, no risk of a lobe ever going flat, and so on. All '87-up passenger car 305s had these lifters. All '87-up 4.3s in S-10s also had them.

 

Many years of the TBI motors from trucks don't have provisions for the factory roller lifters. I'm working on a 1991 L05 in my shop right now that was non-roller. I was disappointed when I found out this, but that's just the way they are. Retro-fit hydraulic rollers can be used, which is what I'm doing in this case.

 

How does that work? weren't all the vortec heads 64cc chambers regardless of being a 305 or 350?

 

I was going by what I have come across on this site. Not specific to vortecs, I am not sure how the vortecs are.

 

NO! L30 heads are around 55 cc, L31 heads are 61-62 cc.