whats the deal with 305\'s

[bikerboyriley1]

well i was thinkin mustangs have 302\'s and done up (cam,headers,carb,intake, exaust) they can go like shit, now for the chevy 305 4 barrel people seem to not like them?? do they have bad fuel economy? or is it just not a very efficient engine??

[ZR1BLAZER]

the motor is very efficiant. but for speed it sucks. the only problem with it is the cylinder bore. i dont remember off hand what it is but it is stock 3.??? were as a stock 350 is 4.000\" as far as stroke the two are the same. the 302s in the stangs are about the same as a 350. (in comparrison) better bore size. so if you want to cam a 305 for slight performance and still keep decent fuel consumption and drop it in an S10, you cant beat the price.

[bikerboyriley1]

hmm yah because i am building up a 305 just because i got the engine and trans for dirt cheap, but i do want to go fast... would i be at the low 300hp range? if i did mine up? cam intake, carb, headers, exaust ,msd ignition??

[bikerboyriley1]

i was under the impression the strock was 3.48

[bikerboyriley1]

i was under the impression the stroke was 3.48?

[bikerboyriley1]

actually maybe high 200\'s might be more resonable

[Murfys_1]

Just don\'t go too radical on the cam. The smaller the engine, the bigger the cam will act.



Your target numbers appear to be reasonable. However, with the stock heads, don\'t expect much more than 5000 rpm out of it. Go with a Performer setup and a 600 carb and you will be quite happy, I would guess.



joe

[afghanimobilerawks]

On 2006-06-11 14:33, bikerboyriley1 wrote:

i was under the impression the stroke was 3.48?



yeah, the stroke is 3.48, however the bore is 3.75..... the mustang 302 has a 4\" bore and a 3\" stroke, which is what makes it more of a power engine....

[Scotty_S-15]

On 2006-06-11 15:39, afghanimobilerawks wrote:yeah, the stroke is 3.48, however the bore is 3.75..... the mustang 302 has a 4\" bore and a 3\" stroke, which is what makes it more of a power engine....



Yeah, the small bore really kills any chance of \"big\" HP from that engine. In fact, even the first ever SBC in 1955 had a bigger bore than the 305. The Chevy 302 (aka 301) on the contrary, is an excellent engine to build, and will yield great HP/cubic inch results. That engine has a 4\' bore, 3\" stroke.

......... Sure the 305s are a dime-a-dozen. And that\'s why. I feel that if you\'re gonna spend any $$ on parts, put valuble time and effort into putting an engine together, why not spend a few bucks more and get a 327 or 350 core to start with.

[batchik2]

That engine has a 4\' bore,



damn thats HUGE! http://www.s10v8.com/images/smilies/icon_lol.gif

[Scotty_S-15]

Well, yeah, relatively speaking, a 4\" bore IS huge to a guy with a 305. About 45 cubic inches huge, not to mention the bigger bore being able to make good use of heads with bigger valves. A little over a 1/4\" may not seem like much...... http://www.s10v8.com/images/smilies/icon_biggrin.gif

[riotpolice75]

the ford and chevy 302\'s both use a 4\'\' bore and a 3\'\' stroke. basically, the bigger the bore you have the better power you\'re going to make because the combustion is better with a bigger bore. the short stroke means the redline is alot higher. the reason alot of people dislike the 305 for performance purposes is because of the bore size. a 305 only has a 3.734\" stroke. that severely limits your combustion potential because the valves are shrouded. valve shrouding basically means that the flow into and out of the cylinder is lessened because the valves are closer to the cylinder wall than they would be in a 350 with a 4\" bore or in a 400 with a 4.125\" bore.



the 305 can be built to make 300+ horsepower easily enough. you just need to make it flow alot better than it does. just dont expect to build a 400 horsepower 305 without spending alot of money or bolting on some kind of power adder. 325 horse is about all youre gonna see with off the shelf parts. if youre wanting to go more than that then dont expect it to have and decent idle characteristics or low end power. the 305 is a torque motor. they werent built to rev.







smith

[TPI]

I just built a 305 because it was very cheap, and to work the bugs out on my first s-10 swap, overheating, etc, which I did, and wouldn\'t care to much if I blew it up. As compared to what I want to build, a 383 stroker!

[ChevyKiD_69]

hey if you ask me there is nothing wrong with a 305. you just got to put time in them to make it run harder. nick

[coppergmc]

I think that the cam to engine size rule is not that big an issue. Actually the cam size should depend more on the stroke length and less on stroke or overall size. Think about it.



The 305 is alright. Usually, you can build a 350 for less money and make more power. Vortec heads and a good cam should make decent power. The 64cc chambers and a flat top piston will yield about 9:1 compression if you use the right head gasket. An alternative to the vortec head is the 58cc 601 casting head. They have 1.84\" intake valves. They still work ok with some porting. You probably wouldn\'t make any more power with a bigger valve due to valve shrouding. So, skip the 1.94 valve swap.



To make up for the bore size you could try a small shot of nitrous. If you plan on using nitrous, port and polish the exhaust runners to help get rid of the extra gasses. Your motor will run strong with the nitrous and still be reliable if you set it up right.

[coppergmc]

I think that the cam to engine size rule is not that big an issue. Actually the cam size should depend more on the stroke length and less on stroke or overall size. Think about it.



The 305 is alright. Usually, you can build a 350 for less money and make more power. Vortec heads and a good cam should make decent power. The 64cc chambers and a flat top piston will yield about 9:1 compression if you use the right head gasket. An alternative to the vortec head is the 58cc 601 casting head. They have 1.84\" intake valves. They still work ok with some porting. You probably wouldn\'t make any more power with a bigger valve due to valve shrouding. So, skip the 1.94 valve swap.



To make up for the bore size you could try a small shot of nitrous. If you plan on using nitrous, port and polish the exhaust runners to help get rid of the extra gasses. Your motor will run strong with the nitrous and still be reliable if you set it up right.

[afghanimobilerawks]

On 2006-06-11 18:57, batchik2 wrote:



That engine has a 4\' bore,



damn thats HUGE! http://www.s10v8.com/images/smilies/icon_lol.gif



yeah, a 4 foot bore is pretty freakin big! lol

[Scotty_S-15]

On 2006-06-12 15:14, afghanimobilerawks wrote:

yeah, a 4 foot bore is pretty freakin big! lol



Ya know, that whole thing went right over my head.... whoooosh! http://www.s10v8.com/images/smilies/icon_mad.gif From now on I\'m gonna write ft. or in. http://www.s10v8.com/images/smilies/icon_wink.gif



But actually a 4 ft. bore is small...... at a power plant! http://www.s10v8.com/images/smilies/icon_razz.gif

[Murfys_1]

Let\'s see... a 4 ft. bore and a 3.75 ft. stroke would be....



SICK power!!







How big would that engine be? It\'d have to be 20 feet across and 25+ feet long! And then you gotta add the supercharger...

[Scotty_S-15]

OK, here is a BIG engine. I wonder if SCAT made that crank??



Biggg Engine (http://www.bath.ac.uk/~ccsshb/12cyl/)



this may have appeared here before.... http://www.s10v8.com/images/smilies/icon_confused.gif

[bikerboyriley1]

alright so i have a 305 4 brl heads, edelbrock 600 cfm electrick choke carb, edelbrock high ride manifold, headman headers, a new cam... i can get specs later i forget, electric water pump kit on my edelbrock water pump, electric fan, engines been cleaned out and all that jaz... will i be close to 300 hp?

[bikerboyriley1]

so the 305 has high torque? isnt that a good thing for racing?

[Murfys_1]

You would be getting close. If you are going to buy a set of heads, look at the S/R Torquer 305 heads. For cam and intake, use the performer matched set with the 600 carb. You will have one heck of a fun engine.



The 305 had 58cc combustion chambers, but most of the SBC offerings are 64cc and 72cc and the valves are too big. Make sure you get the right heads.



Joe

[bikerboyriley1]

alright my engines at the shop and the intake valve om the driers side head is not seating properly but it showed perfect compression... the question is.... can i put 350 heads on a 305??

[my454s10]

On 2006-06-14 11:01, bikerboyriley1 wrote:

alright my engines at the shop and the intake valve om the driers side head is not seating properly but it showed perfect compression... the question is.... can i put 350 heads on a 305??

yes, 350 heads will fit..but most 305 heads had 55-58 cc chambers..and the 350 heads staed with 64cc and go to 76cc..in short the 350 heads will lower the compression on your motor..and in reverse order,,305 heads on a 350 pick up a few points of compression, cause the small 58 cc with a 4 inch bore..there is really nothing wrong with the 305...it just has a small bore...but they can be made to run..there is an articl on the net on how to build a budget 300hp 305ci...my friend held or holds the national record for his class and he runs a 265ci motor with a 3 speed in a 55 chevy...he runs 11.40;s and uses a 390 crm carb...he has a shop in broken arrow oklahoma..called james lee auto and preformance

[bikerboyriley1]

so lowering my compression would not be a good idea?...

[ProdigyS10]

On 2006-06-14 17:39, bikerboyriley1 wrote:

so lowering my compression would not be a good idea?...





really depends on your plans, higher compression makes a cleaner burn and more power... but there\'s lots to worry about with high compression engines if you want it to be streetable... lower compression engines are great for power adders (turbo or super charger or nitrous)

so really its build for what YOU plan to do..

[Murfys_1]

If you are going to redo the heads, it\'s gonna cost you about 300 bucks, and they probably won\'t give you the power you are looking for (unless you are using some sort of power adder, and then why bother with a 305). Take that money and go get the World Products S/R Torquer 305 heads. They should be about 500 bucks and they are made for your engine. Ready to go.



It\'s one of those things that you can save a little money on now if you use the cheaper product, but the trade off is that you will not have what you wanted and have lackluster performance. If it\'s at all possible, put the right head on your motor.



Joe

[Scotty_S-15]

On 2006-06-11 15:54, Scotty_S-15 wrote:............................................ ..... I feel that if you\'re gonna spend any $$ on parts, put valuble time and effort into putting an engine together, why not spend a few bucks more and get a 327 or 350 core to start with.



Spending $300 or $500 on heads......... That was exactly my point.... I just don\'t understand the logic of throwing $$ at a 305 when no matter what you do, you\'ll be at a 50 to 75 HP defecit to a similarly ($$) equipped 350.

[rayL]

i agree with scotty, the only thing id do with that 305 is throw it in the dumpster behind the Wal-Mart. They are a poor investment. You could get a junkyard 350, use stock internals and come out cheaper than trying to make a 305 run.

[Murfys_1]

Or you could do what they said...



http://www.s10v8.com/images/smilies/icon_razz.gif

[chevytech1]

I tried to stay cheap but soon found out it better to do it the way you want the first time.I \'ve been driving my truck for a month and have already put a nother cam in it. now i thinking about changing rocker to 1.6 togive me more lift.

[Scotty_S-15]

But, considering the negative aspects of the 305, I do realize that some guys just gotta be different, gotta do things the hard way to prove a point. And that\'s OK too. http://www.s10v8.com/images/smilies/icon_wink.gif

[afghanimobilerawks]

yeah, i do agree with the fact that the 350 will give you way more power, but the 305 does have some pretty good balls.... i was driving a mid/ late 90\'s caprice for work last friday, which only had the 305 in it, and it had plenty of balls to it..... now mind you the impala i was driving the next day had more balls, but it was slightly modified for the cops.... (ex cop car), and that i know is a 350...... but im still building a 305 myself....

[Murfys_1]

I think there\'s room enough in the engine bay of life for all of the motorized opinions... that\'s what makes us all individuals



http://www.s10v8.com/images/smilies/icon_biggrin.gif

[my454s10]

sell what you can...and do a 427-454 swap...

[redneckgames]

On 2006-06-15 16:51, my454s10 wrote:

sell what you can...and do a 427-454 swap...





then sell and buy a mustang.



just picking on my454



I would go with a 350 off the bat. What is the point in doing something different if everything else is cheaper and better? You will be happier with a 350.

Face it we dont build these trucks for gas mileage, we build them for power. Might as well put the power into it first off.

[riotpolice75]

id do what murfys is saying and go with the 305 torquer heads. or got a set of vortec heads. the vortec heads outflow the torquer heads and are cheaper. 250 for assembled vortec heads versus almost 400 for the world products heads assembled (a piece, i mean)



from what ive seen and read the vortec heads almost always measure out to less then 64cc\'s. ive personally measured 2 sets and they both measured out to 62 cc\'s instead of the advertised 64cc\'s. what year is the motor you have now? there was 2 different 305\'s, the lg4 and the l03. the lg4 was the older one, as in 85 and earlier. its got 8.6:1 compression stock, so i reeally wouldnt consider running vortecs on it without either putting a set of flat tops in it or running a blower or turbo setup. youre gonna lose alot of compression. the lo3 is the 86 and later motor. if your motor is 88 and later its got a roller cam from the factory. compression on those motors is 9.3:1. with a set of vortecs and a skinny head gasket youll be right at 9:1.



go here (http://www.goingfaster.com/spo/carcraft325hp305.html)

theres some decent info on a 305 buildup.







smith

[my454s10]

do a 383 or 400 and lie to everyone and say its a 283 or a 305...the average joe cant pick up that its a 400

[bikerboyriley1]

yah i was thiknin about doin up my 305 for summer since i already have about 200$ shop time into, then buy a 350 at the end of summer and get it all done up through the winter and put in a 383 in the spring

[s10maniac24]

On 2006-06-12 22:22, Scotty_S-15 wrote:

OK, here is a BIG engine. I wonder if SCAT made that crank??



Biggg Engine (http://www.bath.ac.uk/~ccsshb/12cyl/)



this may have appeared here before.... http://www.s10v8.com/images/smilies/icon_confused.gif





5,600,000+ lbs of torque................. http://www.s10v8.com/images/smilies/icon_biggrin.gif

[Murfys_1]

at 102 RPM!!!