Hey there. Ok I was looking at gettin the 350 and doing that whol thing, but I think for the money that I have, a rebuild/and buildup of my 305 wil be fun and a bit cheaper.

I am thinking I will need:
rebuild kit of course
new heads
new intake
new exhaust

Is there anything else that would be necessary for a build up? also I hear Chevy Vortec heads are great heads to use. I am looking for best perf/cost ratio and want a decent amount of HP/torque to come outta this thing! allright thanks and take her easy!

x_wolf

 

For less that the price of a "new intake", you can get a 350.

Not to be a jerk, but...

This has been hashed over so many times it's beginning to sound like a broken record. You're talking about spending a couple thousand dollars on this motor. If you're going to dig into the short block, i.e. "rebuild kit" which would typically include pistons & rings, that means you have to get the block bored and the crank turned. You're talking about buying heads; there are very few head choices that will work well for a 305, and they are all 305-specific; that is, when you get this mega $$$ project fininshed, and you discover like everybody else does that the 305 still gets spanked at every opportunity, you won't be able to transfer them over to a bigger motor.

The total cost of such a project, I will personally guarantee you, will run over $2000. In fact, I would almost be willing to eat it, if you can buy "new heads" of any kind and rebuild a motor and actually have it as good as stock, let alone better, for less than $2500 from tear-down to drive-off. Yours is going to be over $3000 because you have to buy an exhaust system; headers, a high-flow cat, and a cat-back, are $750 just by themselves.

So you're going to spend $3000; but you can't afford to add $150 more to that for a core 350 short block, and come up with 15% more power? That's all that the difference in cost will be, is that core. Every other piece will be exactly the same price, some parts maybe even cheaper, which will cancel out some of that whopping $150 outlay.

Think about it..... 15% more power, for $150. That means if you are contemplating building a 300 HP 305, for the same money you can have a 345 HP 350 instead; if you are willing to bite off on a 400 HP 305, for the same money you could have a 460 HP 350; etc. etc. How can you possibly get that kind of HP/$$$ ratio any other way? Not even nitrous gives you power for that cheap.

I urge you to reconsider, before you create yourself a very $$$expensive$$$ disappointment.

 

I feel like a broken record, too. I've said many, many times, that if you have to touch the shortblock, don't bother with the 305. I'll agree with what RB has to say with the exception that you can make a 305 run better than a 350 for the same money as long as you don't touch the shortblock. The reason for that is you have to do most of the same things to any 350 you'd buy that you'd do to the 305 - exhaust, heads, cam, intake, etc.

I hear about 305's not being worth doing anything to, then I go out and drive mine. Sorry, I just can't agree with that generalization. I also read the latest issue of Chevy High Performance magazine and their "My Generation Camaro" series, and see their 350 was very, very disappointing - after dyno-ing at 380-some HP (of course, they made a lot of decisions that most in-the-know people on this board think were simply stupid). And, saying 305-specific heads can't be used successfully on a 350 if you go that route in the future is also an over-generalization.

Why are you assuming you need to rebuild the shortblock? Mine had 144,600 point-something miles on it when I did the mods in my sig. 17 months and 13k miles later, it's running just fine.

 

broken records are good because it helps some of us that arn't in the know out (at least until I get my books and such and really research) so rebuilds would cost alot eh? hmmm. Well there is a local machinist that is selling a 350 short/long block (can't remember which) with some good internals and an RV cam for 890 bucks.....which isn't bad.

Thanks guys for letting me know whats up with this stuff, I'll keep it in mind for the future! Cheers and thanks again!

 

http://www.larrysperformance.com/data/assemkits.html

I'm too finding it definitely is cheaper to go the 350 route. There's a 350 with 2 bolt mains and forged pistons for $845, has crank, rods, complete gasket set, just put it together, throw on a top end and you're ready.

 

Touching the short block is the key to the $$$$ situation....

There's nothing wrong with a 305 as such. If there was no such thing as a 350, we'd all be building 305s instead, and finding more ways to get power out of them, and we'd probably be successful. But there issuch a thing as a 350, and it's a real common motor; more common perhaps than 305s. That makes it very cheap to buy a used one, and parts to rebuild it are equally cheap. With those economics it makes no sense to pour $$$$ into rebuilding a 305 short block when rebuilding a 350 short block costs no more.

As long as you don't have to do a bunch of work to the short block, adding stuff to a 305 is fine, economically. I question the common sense of buying heads for it though because heads with characteristics that fit the specific requirements of a 305, don't work nearly as well as other heads for the same or less money will work on other motors. You short-change yourself if you buy them and then later decide the 305 isn't enough. Other bolt-on type stuff - exhaust systems, ignition systems, cams, etc. - will transfer right over. They not only cost the same for either a 305 or a 350, they are the same in most cases.

It's all about results per dollar. Not about results by themselves, or about dollars by themselves. It takes less money to get an equal amount of power out of a 350 than it does out of a 305; or, for the same money, you get more out of the 350. I can't answer for everyone on this board but I personally like to get as much as I can out of every dollar I spend. The 350 wins that battle over the 305 by a mile.

The magic concept is you get 15% more with a 350, for the same money. There simply is no other way to buy that much additional horsepower that cheap. If you want power on a limited budget, that's the very first thing you should buy, because it's the cheapest horsepower there is. Anything else you do will cost more, in terms of HP per $$$$.

 

ok so I take it that machinist nearby with the 350 long block for 895 is a good deal then?

I talked to him about the engine, he said 350 long block, internals arn't OEM, RV cam, balanced, honed, but its a 2 piece rear main seal, so I would need a new flexplate and also a new intake.

so that engine for 895 plus a decent intake system and exhaust system, what would I be looking at in terms of cost? Could the stock exhaust system be put back on for the time being? What is it about the 350 block that doesn't allow the intake I have to be placed back on it?

thanks again for the answers you all its very appreciated.

 

Seems reasonable, depending on what it's built out of. See if you can get a list of what parts are used and what machine work is done. All short blocks are not created equal, by any means.

The difference among intakes, is that later model ones have their 2 center bolts on each side at a different angle from early ones. So they don't bole to early heads. But what you're talking about doesn't have heads, so it doesn't matter; whenever you get heads, just make sure you get ones with the later-model intake bolt pattern.

Also, see if he'll shave a couple of coins off and give it to you with no cam; and see if it's a roller block, with the factory roller lifters, like you have now; or if not, what the upcharge would be.

 

What do you mean what its built out of? thanks for the info on the intakes BTW. Ok I hear roller engines are better but what is it that makes them so much better?

So a long block doesn't have heads.....ok...Heads are pretty expensive arn't they?

as far as the cam goes it's an RV cam.....thats all I know.. I dont' know if its flat tippet or like mine (can;'t recall what those are right now) but seeing as I don't have the cash for this for another few months, I probably shouldn't bother the guy. Thanks again!

 

ok we now know whats wrong with it. There isn't anything wrong with the engine internals. I had my friends dad test it who builds hotrod's, so I can pretty much assume he knows what he's talking about. There is no engine rattle internally.

Here are the problems:
-Leaking valve cover (bad gasket)
-Bad Valve seal, lets a bit of oil leak into the combustion chamber when car sits
-needs new plugs
-timing is off
-pully's need to be replaced
-compression needs to be checked but should be ok (hopefully)
-general cleanup

seeing as this is the case.....it wouldn't be a bad idea to just fix this thing up then would it?

thanks.

 

You're right, that's a little of nothing.... when I buy a car, those things are first on the list, I'll do them all (except pulleys ) the first weekend I have it. I certainly wouldn't rebuild an engine just for that.

Give it a try, it's all real cheap stuff, and alot of it is things that you'd have to do with a new motor anyway (cha-ching somebody's cash register a bit extra on the rebuild.... if the pulleys are bad now, a new engine won't fix them; ya gotta have new plugs anyway; etc.) so what have you got to lose?

 

well now that I know all of this stuff is probably all that is wrong with it, it won't be a big deal at all, but I still would really love to push more horses outta this thing, cause 170 is just not enough. What all could be done? I found a site that talked about it before, but cant find it anymore.

cheers!

 

Exhaust from heads to street, every piece of it; and every piece for some other car, such as a 350 TPI, since anything that will fit your L03 exhaust will preserve its bottleneck. Then a cam and a set of heads, again not L03 heads; the best ones to get for that motor would be the ones from a 305 TPI. After that, a set of gears.

When you get to that point, and you're ready to do that sort of thing, come back for specifics. Try getting the engine to run right before you mod it.

 

oh of course. I'm just lookin at setting a plan so I can plan for what I need to do. The heads from the 305 TPI engine were that much different eh? thats interesting. Are they expensive or could they possible be found in junk yards still?? Are junkyards good places to find parts such as these? or would that be a shot in the foot?

thanks!

 

They're quite a bit diffferent. Your L03 heads have these giant obstructions cast into the ports that are supposed to induce swirl into the mixture, but instead, merely choke the port off and cause them to flow very poorly.

Yes the better heads are quite common. The casting number ends in 081. They also came on 87 LG4s and 87 Monte Carlo SSs. You see them on the classifieds on this site all the time.

 

http://www.goingfaster.com/spo/325_h...chevrolet.html

just readin this thing, they say the vortec heads are great for this engine when modded :-) anywho thanks for the info and I'll keep an eye open!

thanks for all of your help RB83L69.

Cheers and I think thats all I need to know! thanks again

 

I wouldn't put too much faith in that web site.... it's got more than a little of its owner's former ego and lack of understanding of automotive (physical) fundamentals, and axe-grinding, and other non-factual stuff in it.... even he ended up geting tired of beating the dead TBI horse and switched to carb, but didn't bother to update his site 2 years ago when he did it.... may still not have for all I know.

"I saw it on the Internet, it must be true!" I don't think so.

Vortec heads have much larger chambers, and so will lower your compression ratio too far for the improvement in flow that they provide. The best heads (as far as junkyard heads) for the 305 are the 081, for later model ones.

 

hmm interesting and yes I didn't agree with the keep the TBI setup idea. The vortec heads can't be milled though? what about those S/R heads that were spoken of that were also in many different areas then just his webpage?

cheers!

 

Vortec heads can be shaved. They are NOT bolt-ons, though. The springs are terrible, the guides need to be cut down, the press-in studs should really be replaced. You'll also need a Vortec-specific manifold (more $'s), and since you've shaved the heads, you'll have to have the intake shaved, too.

The Worlds aren't really bolt-ons, either, in my opinion. They leave a lot of material in the valve bowls when they cast them, and don't clean it up very well with their machining. Every magazine article I've seen on them had "bowl work", also called "pocket porting", done on them. Other than that, though, they're very good heads; with good springs, screw-in rocker studs, 1.94" intake valves.

 

wow, I have to ask, where the heck you guys pick this knowledge up....books? magazines? what? I am learning alot from all of ya, but there is the yearning for more.

Bowl work eh? hmm interesting, ok thanks!

Ok I saw a pair of those 081 heads you were talkin about on the classifieds section are they good performers like the others are after a bit of work? where could i find info on such thing if you don't feel like tellin me :-)

 

HEHE...... these guys (especially RB) has more "wrench time" than you and I have "cartoon time".

I guess I'll just come in and tell ya the same. There's no replacement for displacement.

As far as the TBI, go to the TBI board and read, read, read. Pay attention to Chuck, and JPrevost (although he's switched to a 350), Z28Boy, and quite a few others I can't think of right now. For tips on how to make the car quicker, pay attention to NJSpeeder. He managed mid - low 13's in the 1/4 mile without tearing the shortblock completely apart.

I've done a few things myself that have netted me .500 seconds in the 1/4 mile. This summer I'm really gonna tear into the suspension. Spohn is gonna like me.

I'm keeping a log of everything I've done/doing for posts later. I've spent about $700 so far and haven't touched the motor. I'm getting it ready for the 350 I'm building But it just shows the HP is not the only key to quicker 1/4 mile times.

 

Yeah, that's most of it.

This board doesn't hurt. It has a search feature.

Standard Abrasives has a great set of do-it-yourself guidelines. They are pretty much cloned in a tech article on this board.