305 to 350??

[xjjeep4x4]

this i think is a dumb neeebe question.... but here we go.. i picked up a sb with casting numbers 14010202 says its 80-84 305. what is the big difference between the 305 (crap) to the 350? i got the engine for free thinking i was going to bild a nice sb, i guss thats out the window any help would be nice thanks

[Snowbird13]

45 ci seach

[xjjeep4x4]

so could i just bore it?

[Grumpy_old_fart]

sure...

bore it.

lets see....
3.735 bore for a 305
4.000 bore for a 350

0.265 overbore for the 305 might be a tad much though... I think the cylinder walls are only about .180-.220 thick at best...

maybe you can sleeve it and make it work, but I think it might be smarter just to get the 350 block.

of course, you could make a 331 out of the 305 by using a 3.75 stroke crank.... kinda like beating a dead horse, but cubic inches are cubic inches.... right?

lol... thats funny shit, right there...

305s and 350s share the same 3.48 stroke and deck height... and head bolt pattern...and a myriad of other things. 305s sometimes come with a smaller chamber on the cylinder head, which equates to smaller intake valves, like a 1.84 vs a 1.94 intake valve... .1" intake valve size is noticeable. it gets you from wheezy to breathing.


so, you can use the stock 305 heads and get more compression, but lose breathing ability... would you choke the engine down and then demand it to breathe better by giving it more cylinder? some people say its a good idea. I dont.

if its going in a toyota, leave it alone. if you want mileage, leave it alone. if you want to drive it on the street and make sure your rig doesnt have the power to pull a sick whore off a piss pot so your kid cant beat it up too much, leave it alone.

just my opinion, its worth what you paid for it....

[xjjeep4x4]

Originally Posted by Grumpy_old_fart

sure...

bore it.

lets see....
3.735 bore for a 305
4.000 bore for a 350

0.265 overbore for the 305 might be a tad much though... I think the cylinder walls are only about .180-.220 thick at best...

maybe you can sleeve it and make it work, but I think it might be smarter just to get the 350 block.

of course, you could make a 331 out of the 305 by using a 3.75 stroke crank.... kinda like beating a dead horse, but cubic inches are cubic inches.... right?

lol... thats funny shit, right there...

305s and 350s share the same 3.48 stroke and deck height... and head bolt pattern...and a myriad of other things. 305s sometimes come with a smaller chamber on the cylinder head, which equates to smaller intake valves, like a 1.84 vs a 1.94 intake valve... .1" intake valve size is noticeable. it gets you from wheezy to breathing.


so, you can use the stock 305 heads and get more compression, but lose breathing ability... would you choke the engine down and then demand it to breathe better by giving it more cylinder? some people say its a good idea. I dont.

if its going in a toyota, leave it alone. if you want mileage, leave it alone. if you want to drive it on the street and make sure your rig doesnt have the power to pull a sick whore off a piss pot so your kid cant beat it up too much, leave it alone.

just my opinion, its worth what you paid for it....

well put, thanks
i was just thinking for a min that maybe i could use it.... is if even possible to run 305 heads on a 350? i know the valves are smaller ao i guss not?

[the_experience3006]

It's possible and would give you more compression, but those itty bitty valves aren't going to help you. You could just as easily run Vortec heads on the 350 which have a 64cc chamber likely giving you better compression AND better flow for the same price as just about any junkyard head (in my searching anyway).

[Nskeeter99]

IF you wont to get going then just use it. you could build it up some. if you got the vortec heads like prvesuly suggested, and an intake would add some power. It also could be transfer to a 350 at a latter date.

[xjjeep4x4]

Originally Posted by the_experience3006

It's possible and would give you more compression, but those itty bitty valves aren't going to help you. You could just as easily run Vortec heads on the 350 which have a 64cc chamber likely giving you better compression AND better flow for the same price as just about any junkyard head (in my searching anyway).

i ran the casting numbers on the heads 14014416.... this is what i found

14014416 305 HO, 80-85, 58cc, 1.84-1.5, 165/59cc ports, 7 bolt ex.

so the "ho" meaning high output heads??
why im thinking about try'n to run 305 heads on a 350.... because i have free valves, seal, seats, guids, ect..

[Grumpy_old_fart]

ya must not have read my post.... or just tried to studiously ignore it.

[xjjeep4x4]

Originally Posted by Grumpy_old_fart

ya must not have read my post.... or just tried to studiously ignore it.

i read it and see what you saying. my deal is my 350 heads are done for.. they leak like a mother, i was just thinking ive got the heads & new valves, seats and all the goodies to go with it for free! yes being a cheap mother fucker that i am.... maybe it will work? maybe it will suck so bad ill have to save up for a engine. it might have to work just to keep the old tree-fifty go'n!
thanks grumpy

[DrillANWR]

So I thought this was retarded at first. But I think I might be retarded.
Are you saying the heads are interchangable between a 305 and a 350? How similiar are the blocks?

[El Jefe]

Originally Posted by DrillANWR

So I thought this was retarded at first. But I think I might be retarded.
Are you saying the heads are interchangable between a 305 and a 350? How similiar are the blocks?

Other than cylinder bore, on these years they're identical.

[92solidaxlechevy]

find a 70's or 80's farm truck with low miles. around here there $500 to $1000 disassemble new rings seals oil pump. reassemble, done! Why go thru all the work for a 305 just find a 350 they were the most mass produced v8 on the planet AKA cheap as fawkin dirt.

Why waist your time with tinkering with a 305? Do you not have craigslist? I just found a 350 rebuilt bored .30 over guy needs it gone yesterday $500obo yeah its in iowa but i am sure the same thing will pop up within a month on your local CL.....

[Level_B]

Save up for a LS GM motor, like a 5.3 or 6.0, they can be found for cheap, and they make nice power with lil amounts of money, I found my LS 5.3 for 400 bucks of craigslist and it was in the truck so I could here it run, only has 116k miles on it, I'm swapping it into my 93 Chevy once my 241k mile 350 hits 250k or starts slowing down...

[ADChevy4x4]

416 305 heads on a 350 is a cheap way to boost compression ratio.On a mild engine the smaller ports and higher compression will give more midrange power.416 heads are a lightweight casting and must be checked for cracks.

[MrWillys]

If you already have the heads, and can't afford another set of 350 heads then bolt them on. They will work, but most intelligent people know that the increase in compression does not offset for lack of flow.
If I were young, and had other priorities then I would use them and put the savings to better use.

[Grumpy_old_fart]

Originally Posted by DrillANWR

How similiar are the blocks?

you arent seriously asking this question, are you?

[frikenwoodro]

Originally Posted by Grumpy_old_fart

you arent seriously asking this question, are you?

He may not be but I am


Or am I?!?!?!?!?!

[Grumpy_old_fart]

Originally Posted by frikenwoodro

He may not be but I am


Or am I?!?!?!?!?!

you?

yer bein a tard...