VinnyNeedsHelp

I have a 86 305 engine that i got for free and i am wonding if i would be able to turn it into a stroker engine. if anyone has any ideas on this please let me know.

TheGreatJ

Anything can be stroked. A 383 or 400 crank (3.75" stroke) in a 305 block will build a 335 IIRC, and you can always go bigger with offset-ground cranks and the more exotic aftermarket crankshafts. You'll have to have it balanced and you'll have to clearance the block in a few places but it can be done.


If you don't have experience with building/modifying engines I wouldn't recommend this. You'll have a lot of learning to do and it's easy to kill a motor with just one or two simple mistakes. You'll also need to upgrade everything else to support the extra airflow, i.e. exhaust, heads, cam, etc. will all probably need to be changed to get any real power out of it. It takes a few bucks to build a good stroker motor.

VinnyNeedsHelp

The thing is I dont know much about Engines yet but im just trying to get ideas of what can be done with it because i was told that a 305 could only be turned into a 347 stroker but yet no one has a 347 stroker kit for a gm. and the only stroker gm engines i know of are 383's which are upgraded from stock 350's.

87z-28man

Powerhouse makes a 335 stroker kit for the 305. i first saw it in on cardomain.com in a kids IROC, and from what he says his numbers are, for the price of the kit its worth it if you want to build up the 305. yea alot of people are going to tell you to say screw it and build the 350 but hey, building a 305 is something different i guess. wont handle as much power, but it'll also be cheaper. heres the link to that stroker kit Powerhouse 335 Stroker kit

good luck and keep us posted as to how it goes.

VinnyNeedsHelp

the link didnt load to a website. can u give me the address.

85_305

stroking a 305 is a VERY poor decision that should ONLY be carried out by someone who knows what thier doing. By stroking a 305, the the valves will eventually hit the piston which equals I'm sure someone will chime in here and give you the technical aspects of it, but unless you go thru MAJOR head work and block work, along with money, it is NOT worth it. But boring it out, on the other hand..

DevilsAddvocate

Boring it out to what? Wont work either, look kido i know its hard to get rid of something that ya have (god knows i did the 305 build as well) but dont put any money into the bottom end of your 305. 350s are so common now adays power per dollar you would be better off tossing the 305 and getting a 350. Hey if it runs go ahead and use the 305 and throw a new top end on her (vortec heads are my recommendation cuz of the valve size) and have fun with her till she breaks. Thing about stroking a 305 is the bore is already way to small for the stroke and increasing the stroke even further will just choke it for even more air. If your rich and have some extra cash sitting around and just wanna build a 335 just to be different hey go 4 it. But if your on a budget i say use it till she breaks and get a 350.

RedIrocZ-28

I'm gonna have to agree with these guys about the 305 and not building it. Its proven that unless you put a supercharger or a turbo... or 2, on a 305 that you'll make more power with a 350, you are increasing your avaliable volume by 13%. You would need a littel over 9 cylinders on your 305 to equal the volume of a 350. Your cylinder volume is 38 cubic inches while a 350 is 43.75. Multiply those numbers by 8 and you'll come up with the respective 305 and 350 numbers. What I am saying is that by moving to a 350 you have gained the entire volume of 1 of your cylinders... PLUS.... so its just that much more cost effective and rewarding to go to a 350.

anthony714

yeah hoss,they right,unless you just want a quick cheap orginal engine,dont mess with a 305 if your looking for more power,which apparently you are since u wanna stroke it..loook at it this way..you got it fre...so what...the only thing you going to keep on that short block if you stroke it is the block...so what...a 350 block can be had for almost free...and i mean free..so if you going to be replacing everything else in the 305,why not just run the 350 version....seriuosly,,your getting all new crank rods and pistons for any stroker kit,,new cam regardless....and even if you keep your heads im sure theyll need work cause you wouldnt put old head son a new engine....if you want to just drive,just rebuld 305,if you want power,start with 350 platform...and actually it might be cheaper to buy a 350 block cause aeven though i havent priced the stroker kits,im willing to bet a 350 stroker kit cost less than the 305 kit ,which would offset the cost of the 350 block youll need,,,just a thought

82355

Bad idea. Don't do it.

305s are junk because of their small bore. Adding a longer stroke to too small of a bore is just making it worse, you will gain power because of the added displacement, but it is not very effective.

To the guy that said boring a 305 as opposed to stroking it for performance reasons. You're wrong to. The small amount of added displacement you are going to get from even an .060" overbore are insignificant and you still have a small bore, ****ty engine.

Martin

DevilsAddvocate

What i said, i think he ment bore it out to the same diameter of a 350 tho and that is not possible.

85_305

No, I didn't mean bore it out to the size of a 350. I was simply saying that boring, used on *any* engine tends to increase performance.

DevilsAddvocate

Oh ok well anywayz not worth it.

Nitro

Don't try to stroke the 305 get either a 327 or a 350 I recommend the 350

85_305

^Good luck trying to find a 327. And if you *do* find one, they will cost a fortune. Very good engines; they are basically bullet-proof.

Devilsadvocate- Even boring it out wouldn't be cost-effective?