88drop

Just wondering if any one of U knowledgeable people could tell me what Gm cars came stock w/305 Vortec heads (my impression is it was primarily a full sized p'up thing but what years)? I would like to find a cheap donor pair to put on my 88 305 TBI motor. Thanks in advance.

GTA matt

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96 to 98 305 trucks

mw66nova

iTrader: (13)

honestly, i don't think there is a such thing as a 305 vortec. RB83L69 could probably tell you exactly(cause he always can)

from what i am to understand, you take a vortec head off of a 350 and have them decked like .030 or something link that to get the combustion chamber volume down. i think it would probably cost less to get a set of fresh heads from vortec. don't forget to get a new intake as well.

GTA matt

iTrader: (1)

They did make a "vortec 5.0". Now im not sure about whether or not it had the 350 heads on it. you may be correct, i just never paid enough attention to them. i'm sure if you run across a vortec 5.0 truck the heads will swap right out though.

ShiftyCapone

iTrader: (7)

There was a 305 vortec but it did not share the same heads as the 350. I still haven't seen any proof that the 305 vortec heads are worth anything. I have never seen a set up close nor do I know any of the specs on them. From previous disscusions they seem to be close to their big brother but lack a few certain things.

IHI

iTrader: (1)

Stay away from the 305 "vortec" heads, they do not compare at all to the regular 062 castings that everybody looks for. CChamber is totally different than the real vortecs so effeciency suffers, take a look at these flow numbers. I bought a pair of "vortec" heads from a shop in Arizona, but through our many conversations he never mentioned they came off a 305 pick-up and I never asked.

The numbers in larger print are what my 305 "vortec" heads flowed, the little numbers above them are from a set my buddy had flowed by the same shop on the same flow bench, his were the 062 castings. Numbers dont lie, so if your going to all this trouble, get the right heads the first time. You can always reuse them on a different motor when you have the cash to go that route.

http://img.villagephotos.com/p/2004-...cflowsheet.jpg

<img src='http://img.villagephotos.com/p/2004-9/824085/vortecflowsheet.jpg' width=500 height=623 img>

SSC

People confuse centerbolt VC heads with Vortec, just like vett 350 and high performance factory engine. The vortec 305 heads arent bad for a 305 build they do flow more then 416's in stock form. I decided not to use mine since the cost of the intake manifold is nearly the same as having a set of heads gone through.

blacksheep-1

I have just installed a set of 1.84 valve vortec heads on my (mostly stock) 305. I will keep you posted on the results, I have some before dyno sheets, I'll try to get some after sheets when I get time.
Stay tuned.....................

88drop

Thanks all for input but I think I'm confused now. To SSC:U say Vortec 305 heads flow better than 416"s, what are 416's (R they the stock heads)? To IHI:U say the 305 Vortec heads do NOT compare to the regular 062 castings , again what are 062 (stock)? Thanks again for all replys & blacksheep, I look forward to hearing the results from Ur Vortec install. Oh, & someone said the 305 Vortec are not real vortec heads...what do U mean by that. Sorry if I sound like a total idiot

ShiftyCapone

iTrader: (7)

416 heads were found on LG4's and various other TPI and 305 applications up to '87.
062 heads are the 350 Vortec head with 64cc chambers found on trucks, vans or whatever else used a '96 thru '00 vortec 350.

EDIT: Both the 416's and 062's are stock GM castings. The numbers are the last 3 found in the casting number.

IHI

iTrader: (1)

I'm not 100% sure on runner size between the 305/350 vortec, but I can tell you if you were to set these heads side by side you will notice the diffence with the combustion chamber design. The real vortecs have the peanut/kidney bean shape, the 305 vortecs look like your everyday run of the mill oval chamber.

Fast355

iTrader: (2)

The vortec 305 heads I have seen have the same chamber as the vortec 350s just a little smaller. The ports were identical with just the intake valve being smaller.

I helped a buddy add them to a 400 in a chevy caprice (after drilling steam holes) that is used for towing. With a comp xtreme 268 that little 400 will scream. The heads came off of a wrecked low mile 2002 chevy van 305 if that is of any use.

88drop

Thanks all I know feel enlightened -I'll need 2 check casting # for my TBI heads.Anyway, again thanks all.