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305 heads


bill179
01-28-2004, 11:18 PM
what is the combustion chamber cc on 1987 305 TPI cylinder heads?
any other information on these heads would also be useful and appreciated.

swollen balls
01-29-2004, 11:00 AM
55-58 cc's
nice heads to put on a 350

89IROC&RS
01-29-2004, 05:45 PM
i think they are actually 58cc, however, they suck. small valves, poor airflow, shitty chamber. all around poor head. better head is world products 305 torqer heads. or use vortec heads, with .015in copper shim gaskets.

4onFloor
01-29-2004, 05:53 PM
ya, there not the best heads. but if your on a tight budget like i am, there a good head to use on a 350. they'll raise your compression, since i think 350 heads are 64cc

89IROC&RS
01-29-2004, 06:19 PM
vortec heads are 61cc, and with the copper shim gaskets, will proby give you more compression than the stock setup, havent crushed the numbers on that one. so yeah, if you just bolt the 305 heads on a 350 it will raise the compression, but definately do the math, you could wind up with like an 11:1 compression. no good for street. and as far as budget, youd probly be able to get the vortecs for close to the same price, find a wrecked 96-99 tahoe, silverado, suburban, or GMC equivilent, with an R code V8, and you got em. just a pair of Iron heads as far as the junkyard is concerned. no different than the 305 heads. but if you go after the vortecs, be sure to get a pair, with the casting number ending in 062, not 908.

4onFloor
01-29-2004, 06:37 PM
what i did was, i bought a wrecked 1990 camaro RS/305, for $175, i pulled the engine and tranny and a few other things. i'm using the 1990 heads on my 71 350, i'm using the throttle body and wiring harness to run fuel injection in my 71. not a bad price for the heads and all the stuff i got, and it only cost me $18 and a little time to rebuild the heads, i also did a port and pollish job.

89IROC&RS
01-29-2004, 06:57 PM
not a bad use for the parts, pretty inventive actually. me likey, but still, the vortecs are just as cheap, and flow nearly as much as bowtie heads, unported. i scored a complete R code 350 for 100 bucks, only thing wrong was it had collapsed lifters, and the bearings were starting to go, thanx to an internal coolant leak. but everything else was fine.

4onFloor
01-29-2004, 07:16 PM
i'm not too familiar with Vortec's. I tend to stick with what i know works, and toy around when it doesn't cost me money. I'm sure it's a better engine, or they wouldn't have slapped a different name on it.

89IROC&RS
01-29-2004, 07:32 PM
lol good point :) but i have yet to see a 350 with those heads, run less than 400hp. that is in hot rod and such. thats proof enough for me. not to mention i have seen the flow numbers, and the possiblities for improovement. heads are amazing. thats why i just cant let em go, i love em i love em i love em ;)

bill179
01-29-2004, 07:54 PM
my friend is building the engine for as cheap as possible and wants alot of compression and i told him to find vortec heads in a junkyard but he didnt seem interested even though the manifold he wants fits vortec heads.


but i agree that vortec heads are the way to go

4onFloor
01-29-2004, 08:10 PM
get your smaller cc heads, and combine those with a set of flat tops. that should raise the compression

89IROC&RS
01-29-2004, 08:47 PM
your friend is more interested in 305 heads than vortecs???? not to be a dick, but he needs to go back to school. that or he is wayyyy to focused on the chamber size. there are many many other aspects that go into a good head, and making power, than the chamber size. a set of flat top pistons, shim gasket and vortec heads will give you 12.5:1 easy out of a 350. and like i said, you can get the vortecs for the same ammount as the 305 heads. ah well, thats my advice, if he really wants to get the 305 heads, let him. hes just making a mistake in my opinion.

bill179
01-29-2004, 10:46 PM
hes got the heads now they were on the engine when he took it out of the car and i think he has flat top pistons to put in the new engine already
oh well ill talk to him tomorrow

4onFloor
01-30-2004, 05:41 PM
what year and what size of block is he putting these 87 heads on?

comp
01-31-2004, 08:48 AM
if you use a 305(small bore) you help air flow by "relieving" the top of
the bore back just before thehead gasket line. don't go down to top of
compression ring travel i n bore :smokin: :smokin:

89IROC&RS
01-31-2004, 02:59 PM
or, get a 350 ;)

crapmaster4000
01-31-2004, 10:58 PM
Ive got a 350 with 305 heads. They are alot better than just plain 350 heads, expecially if you dont have any money. If I had more money, I would probably have vortec heads but I dont. People for some reason seem to think that 305 heads are bad, I'm telling you they arent.

Genopsyde
02-01-2004, 02:11 AM
i have 305 heads on my 305.

89IROC&RS
02-01-2004, 11:03 AM
well, i admit i dont know any flowdatta on the 305 heads, but i would imagine they arent very good, and baised on my experience with engines, i will continue to assume that they are door stops untill proven otherwise. the price argument for the 305 vs vortec heads is moot, where would you get the 305 heads?? junkyard more than likeley, so if your at the junkyard already, why not find a wrecked 99 tahoe or something and yank the R code heads off it. same price, and the vortecs flow more air than bowtie heads with the same size valves. to me its a no brainer. but eh, im not gonna change the wold, just give yall the info and let you decide what to do with it.

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