I wish you guys were around me. when I need space in the garage the 305's go to scrap and the cranks are given to my machinist. last time 2 283's and 3 305's went, I like the heads 60CC are great for the dish piston 350's and I don't spin much more than 6500 anyway. If I didn't have a bunch of engines they are good engines just small on the cubic inch side.
I agree if you need to re build your motor you might as well re build a 350 BUT if you can find a good running 305 cheap then why not use it? $100 got me a good used motor. and everything that bolts on to a 350 will work on 305. most folks think mine a 350 but I always tell them its a 305. its got plenty of power to push my 50 coupe.
I've owned several 305's over the years and in stock form the first ones were all the bad things people said about them but that is easily corrected. Yes pistons are a little more expensive but not that much and if you are in an area where 350's are rare and expensive and the 305 is readily available it can be made to work very nicely. Victor P/N 5745 head gasket for 305 ; .027 compressed thickness X 3.839 bore. In defense of the 305 a basically stock 305 Vortec with the 350 Ramjet roller cam, 4 bbl. and headers is capable of 345 FtLbs FWTQ @ 2000 with a peak of 360 @ 4000 and 320 FWHP @ 5500 though mufflers on 87 Octane. The 305 and 350 Vortecs used the exact same stock cam. The 305 Vortec heads are actually a pretty decent head for a 350 even if they aren't quite up to the 350 Vortec specs. By comparison a stock "300HP" 327 with 1.94/1.50 Double Hump heads from the 60's with headers makes a true 370 FtLbs from 2000 through 3500 with 277 FWHP @ 4500 and requires premium fuel. The 305's respond very well to the Summit 1102 and 1103 cams and the 1103 really sounds racey in a 305. Just about every "budget" auto parts wholesaler offers the same grinds, PAW, Sealed Power, Elgin, Wolverine, Blue Racer, etc.
Thank you engine builders' for proving the nay sayer's wrong A-GAIN. Esp. with real world number's. Run 'em!
are you CRAZY, man?!?!?!? Scrappin' 283's? OH...this is the big one 'lizbeth...this is the big one! Me or my family are always a day late, dollar short, other side of the state when this happens.
I forgot to mention, the '395 roller cam is also the stock cam in the roller cam Marine 305's. FWIW, after I finish my OT truck 355 build I plan on building a 305 with a roller cam shortblock and '416 HO heads and an iron Q-Jet intake using all factory Chevy parts except for pistons and headers. Projected HP is 335 @ 5500. Why? Because somebody told me not to.
we just dyno'd a 305 with 416 heads 1.84 intake valves, edelbrock #7101 intake 1" spacer holley 600cfm #o-4776c and a crane cam #113941 ended up with 328hp at 5000rpm
I have a 305, 30 over, dish pistons, 416 heads (60cc) with unshrouded valve pockets, new springs, guides and valves. Roller block but no roller cam, it has those weird cut outs in the lifter bores. 10/10 crank. Edelbrock performer with the 600 cfm edelbrock carb and hei. The engine is going into a parts hauler/fetcher. It will be in front of a 700r4, 4.10 rear and tires in the 30 to 33 inch range depending on what is cheap. I see this operating at idle through 3000 on most days. I can't see it ever going over 5000 in this vehicle. I need help in finding a good cam that makes some power from idle to 4500 and is easy on the gas. The motor has not been assembled yet if that helps. Any ideas on cam and head gasket thickness?
I've had a few 305's and loved every one. You won't blow anyone off the track with a stock one but for running around they work great. I think most people bash them because they think that's what the cool people do. They're great little motors.
from what I recall, by the time the 305 was created all manufacturers put their engines on a diet to meet CAFE requirements IE: they are thin wall castings without much beef to handle hopping up. As far as valve sizes, as pointed out, shrouding (small bores) has a profound impact on power potential. Having said that any SB engine is useable for transportation, some cube combos respond to basic hop up tricks better and are well documented.
They were offered in the Monte SS in an HO version. I don't recall what they were advertised to produce but they were moderately peppy. They were real popular with the short track guys in the '80s at least down in the Ozarks. They were limited by the way they breath, need a cam change and some port work to be peppy. They could also use a compression boost at least up into the 9 or 10:1 range. TRW has higher compression pistons for them that are relatively inexpesnive. Cheap enough for claimer motors anyway. I haven't know too many to get good mileage as a rule. The raven has one in his '27 with an OD that gets around 10-12 MPG. Now thats a 305 in a light car with an OD. Of course it gets the same mileage on the highway or around town. If I had one I owuld build it, in a light body for a small outlay and some sweat equity you could end up with a fun little driver.
If that is indeed the mileage that he is getting, then I have to say that something is very wrong with the setup, the tuning, or the gearing. My A has a 1989 305, which was a TBI engine. It is stock, save for the manifold and a 500cfm Edelbrock carb, roller rockers and an electronic distributor. It is backed with T56 (0.50:1 OD), 6.00:1 rear gears, and 31" tires. Running at 65 MPH, all day, with a GPS verified speedometer, it gets 28.5 MPG. Off the freeway, it gets 19-21 MPG. I highly recommend that anyone tuning anything take advantage of modern technology. I use a data logging meter for engine functions, including an O2 sensor and vacuum gauge. These are not particularly expensive, nor do they need to be installed in, or stay in the car. The O2 sensor bung can be hidden out-of-sight, and plugged when not in use. This is what I use (there are other good ones too): http://www.zeitronix.com/Products/zt2/zt2.shtml#LCD It is a totally portable system, as are most, so they are perfect for a car club to a couple of buddies to buy. It pays for itself in gas and frustration, in short order. Performance need not be wasteful.
Thanks, I'm going to do some port work and 3 angle valve job on mine. Can't give away my recipe just yet though. I second that. Every carburetor equipped 305 I have had any experience with got at least in the high teens and those were in a full size pickup and a '77 Malibu. I've had 305's in a '78 Malibu, '77 Camaro, '79 Camaro and a new '81 Z/28 with a T10 and 3.42 posi. I drove 'em all like I stole 'em and never got less than 18 MPG, normally 20+. I slipped an Engle RV-100H in the Z/28 and could hold my own with '81 vintage 350's with no loss in mileage. I also realize "holding your own" with an '81 350 isn't saying a whole lot..........
we are trying to put together a front engine corvair at my budys place and we were given a 1988 roller HO 305...found a stroker kit for the 305 for under 600$ and plan to do this build on the motor....the car was 150$ saved on the way to the crusher..my friend was very pleased with a free 305 out of a firebird....and all for under 2k$ cash we/he will have a nice little rod...btw we will have left overs if you corvair guys need any thing......1966 corvair monza 900 with extra engine parts and a neat set of cherry bomb headers and mufflers attached....I love any V8 i can afford to build and get for the right price be it any make...just do a little research and a lot of planning and measuring...buy an ok welder and cheap set of portable torches and you are building cars my friend.....o and help from friends is always good toojust remember to keep smokes and beer around your shop as well or the torch light dies real quick on a Friday or Saturday night
Yep, this poor old horse gets beat to death just about ever other week. Easy econo*ics. the cost of redoing a 305 when you buy pistons is about double the cost of doing the sa*e thing to a 350. Check any parts supplier's web site and co*pare the prices. And for that extra cash outlay you get less power when you are done.
Don't rebuild a 305. Just grab a used one and go. There are a zillion of them out there, many with low miles. I can buy them any day for $300, tops. Clean, paint, install, drive for 3-5 years, repeat. Can't beat those economics. Big horsepower is not everything. You can get 200 for $300.
A bunch of the 350s out there are actually 305s if you check the numbers. Yeah, its got a old vette motor in it...
This is very true! I have two customers that love their 350 more than their kids, and would not have a 305 on pain-of-death. I just keep letting them live the dream.
i allways like the put something big in it people. hot rods are made to be driven. with gas at $3.00 or more a gal. the 305 makes a good motor. i use them.
A 305 is still a POS. Do the same mods to a 350 and then talk about it. Theres no substitution for displacement period.
If horse power is your game, the 350 is the motor, but there is nothing wrong with the 305 for just plain cruisin. Had mine for 16 years in my coupe and with a Q-jet and the factory 82 Camaro aluminum intake I got 20mpg at 65 mph. Added a Edelbrock performer intake and Holley and dropped to 13 mpg. Put a Edlebrock SP2P intake on and back to 20+. Turn the key, starts and runs all the time. Had a 2 bbl 305 in my '57 Chevy and got 25mpg at 55mph with a 4spd. It's all about drivin, not racin to me. A 350 can beat me to the gas pump any day.
I have heard of high output 305s in 80s SS montecarlos, I owned one and have drove sevral SS montes but Im not familiar with the diffrence in specs on them if any??? The ones I drove would turn on pretty good but a diffrence in gearing could have been a partial factor in their performance???
The smaller displacement is no piece of shit. Well matched part's, fine tuning trump bigger is better mentality every time. Esp. when the nay sayer(s) have multiple thread's of negativity.
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