Which would be the best to build so that I can still say I have a 5.0 under the hood?

 

If you are determined to stick with a 5 litre, go 302 all the way. With the 4" bore, you can fit 2.02"/1.6" valves. And with the short stroke (3"), you can rev the snot out of it.

 

You could throw a 350 in and say it's a punched out 5.0 liter.

Or better yet, you could throw in a 350 block with a 400 crank (383) and say you have a punched and bored 5.0 liter.

Or you could just buy a 'Stang. :sillylol:

 

The 307 would be the cheapest way to make the most power.

 

I thought the 307 was a stroked 283 (289?) that was used on smogged out motors and only came w/ a two barrel? I understood they couldnt be revved very high and were generally pieces of junk when compared to the 302 or even the 305. I know you can go fast with one because a buddy of mine had one in his monte and went high 12s, but he had some ridiculous suspension work done - and it was his racecar. But now he has a 350 and runs low 12s...go figure. Why do you want to stay under 5 litres anyway? Is it to fit into a certain racing class? If its for road racing or you are willing to have a high revving motor under 5 litres, i'd stick with the 302. Why is the 307 the easiest way to make power cheaply?
Matt

 

I like to have something that not everyone else has, and most of these cars have a 350 or larger engine. Plus the wow factor of being beat by a 5.0L is just great, that and I don't want to change the decals on the hood.

 

The 307 leans towards the power end of the spectrum (vs. 305) of the 5 liter SBCs. Chevy just never did anything to deliver them with any power. The 305 fits your description as much as the 307 did, except GM did make some 305s that put out a little power.

Going from a 305, you'll give up a little torque with a 307, but get better cylinder filling for more power on the other end. Make the same power-oriented improvements to a 305 and a 307, the 307 will make more power above 5252 RPMs.

I'd accept a ready-to-run 307 shortblock if one was given to me.

 

i'd take 307 over a 305, but would take the 4" bore of the 302 over both

 

If you want gas mileage build the 305, if you want a hotrod build the 302 and put real good heads, big cam and steep gears in it, if you just want a good all around engine build the 307 with good heads and small cam & headers, if you really want to go fast build a 350 or 383 and LIE about it

 

And what's the charm of spending $2000 or whatever on building a motor, and not making it as powerful as possible? i.e., what's the "wow factor" of losing to a junkyard 350?

I wouldn't fool around with any of them. Considering that they're all about 45 CID less motor than a 350, and you're going to have to buy a core motor anyway, and one for of those motors you'll actually have to buy a 350 core and spend extra money to shrink it down and take out horsepower, unless you're racing in a class with a CID limit, you're short-changing yourself.

There's no law that says you have to change the hood decals. You can just leave them alone.

This is a typical fantasy we see around here, in people who have never built a motor or otherwise seriously modified a car. It's pretty easy to think when we're beginners that somehow we can defy the common wisdom and do it better than everybody else does; sometimes it takes a few lumps before we realize that the same laws of chemistry and physics apply to us all, and our lack of experience doesn't make us smarter than those who have some BTDT. In this particular case, it's the simple fact that the more gasoline molecules you burn per engine revolution, the more power you get. It's so simple, it's easy to outsmart yourself, thinking you have some magc formula to work around it, until you've experienced the disappointment a time or 2.

Don't use your own money as the ammunition to shoot yourself in the shorts with, which is excatly what you are proposing to do. This hooby is all about HP per $$$$. A small motor fails miserably by that measurement. in other words, you have to spend vastly more $$$ to get equal horsepower, using a smaller motor; it's a whole lot cheaper and easir to get let's say 400 HP out of a motor when it's 1.14 HP per CI, than it is to get the same 400 HP with a smaller motor where you have to produce 1.32 HP per CI.

 

let me ask this...going on limited knowledge here

Now, aside from the Chevy 307 weren't the BOP 307's small journal motors? If you were going 307 I'd go with a BOP one(provided what I said is true)

 

307's had a medium journal size , just like the later 327's and 350's, Mains-2.45"-Rods-2.10" 400's had the only large journal main at 2.65"

 

302 for sure... its FAR better than the 305 or 307.

The 4" bore lets you use big valves, and the short 3" stroke gives you a nice, broad powerband thats good for 8000rpm if built right.

The 302 is what the '67-69 Z/28s used... and they were known to kick some serious ***

But... RB is right. period.

No matter what you do to a 302, 305 or 307, you will ALWAYS get more out of exactly the same parts if you use a 327 or a 350. Its simple physics. More Motor = More Power.

But of the 5.0L engines, the 302 is by far the best engine. But its still not up there with a 327 or (even better) a 350.

 

where can you find a #'s matching 302 because they are a hard motor to find. if I were you I would just get a 350 or 400 and say its a 5.0L visually they are identical no body can tell the difference. but make sure you you cam it up or you will get smoked by a rustang and that's not cool.

 

400's have 3 freeze plugs per side, unlike the others that have only 2.

 

Right. If you find one that has 3 freeze plugs, it's a 400. No doubt at all.

However, if a block only has 2 freeze plugs per side, don't assume it ISN'T a 400. Some 400s only had 2 holes per side.

When in doubt, check the casting number.

 

Like RB83L69 you don't have to change the hood stickers(decals stickers they all stick don't they?) Drop in a built 350 and claim it's the 2.8 v6 and go around stomping imports, making them think their cars are slower than they are(I just gave my self an idea). Some of the fun in racing is not letting the other guy know what you got