I have a 350 that was rebuilt 10 years ago in my 70 chevelle.. All I know that it was bored (unknown amount), it has an RV cam, with edelbrock performer intake manifold, and edelbrock 650CFM. I have no idea what the other parts are in it, probably cheap stuff.

Does anyone have any suggestions on what I can do to get my motor to roughly 400 to 450 HP without a complete rebuild and without superchargers or anything like that. Bolt on parts would be nice if it could happen. Thanks in advance and I must tell you that I am a neewbie so if you dont mind speaking 3rd grader to me then it would be greatly appreciated. Thanks again in advance.

With what you've said I'm going to guess the heads are stock 1.94/1.50 heads. Realistically they could be anything though.
I'm thinking you are maybe in the 290-320hp range.

Without tearing into it fairly deeply the only thing I might suggest would be a small nitrous setup... 70-100hp hit to get you to 400hp.

Other than that I'd think aftermarket heads and a bit more cam.

What tranny and rear gears are you running?

David. If you want to make 400+ hp with a small block. The first thing you need is a good bottom end. You need to find out what crank, rods and pistons you have. If you have cheap cast parts in the bottom end and you start stressing them. They will let go. After that, You can decide on the cam and heads to use for the power your looking for.

The rebuild cost me 2700$ 10 years ago and it was the stock engine. I just put a 700r4 trans in it because my t350 just took a crap (wanted the overdrive). The gears are stock in the rear (2.73) 10 bolt/8.2". That will be changed soon hopefully with an upgrade to a 12 bolt with 3.90 gears.

I really wish I knew what is in it but I don't. I'm guessing the parts are decent but nothing like they should be. I do know it has a good cam in it because I remember my dad opting for the better cam.

I dont really want to do nitrous if possible. Thanks again.

OK. I was thinking you bought the engine and didn't know what parts were in it. $2700 I don't think they used cheap parts.
Take a look at these kits.
top end kit 1 (http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_376471_-1)
top end kit 2 (http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_376472_-1)

Awesome. That sounds like exactly what I need. Do you think edelbrock is the best stuff to get or is it just because they have the parts already teamed up?

There are pros and cons with everything. Edelbrock makes a very good product. There are better and there are worse. One of the car Mag's (can't remember which) did a test on the Eddy top end kits and found that there HP claims were very close to the Mag's results.
The best part about a kit is all the components are matched to work together and they are usually cheaper than buying the parts separately.

You are awesome. That's what I needed to hear. I would love to do something like that. Do you think a novice like me could take on a project like that? I do not know anything about engines but would love to do it myself. And im guessing I need to pull the engine to do that upgrade, am I right?

there's always the holley systemax too they claim 425 with their small block

Say I do the edelbrock setup with 435 hp, what type carb should i use.

Install a set of Dart 180cc heads {iron eagles} or edelbrock preformer rpm heads
install a cam that is like 222/230 @.050 to 230/236 @.050 on a lobe seperation of 110-114*. Run a preformer rpm intake with a 650 double pumper or a 750 vacuum secondary. Probally a 2,500rpm-ish stall and 3.73 rear gears

So how hard would this project be for someone who knows how to read instructions but doesn't know squat about engines. I think I could do all the add ons but replacing the camshaft seems difficult. Is it hard to replace the cam and does the engine have to be pulled for that?

can you turn wrenches or know someone who can guide you along the way? if so then go buy a chevy engine rebuild book and giver.

That's what I'm doing - waiting for the book to arrive in the mail. I'm thinking of getting a rebuilt 383 shortblock, and finishing the rest myself. I haven't made any decisions as yet on the source of the shortblock, or any of the other parts.

Going from 2.73 to 3.90 gears is going to be a world of difference. If your just after the fun factor do the gear change first and throw in a good posi. That may be all you need. With the performance cam you will have to change the gears anyway.

Okay. I was going to change the gears first anyway along with a new housing. Don't know what kind of housing I want yet. Was thinking of just a standard 12 bolt but I was also thinking of a Fab9. Anyone have any suggestions on that? I was also thinking of eaton posi as well. Thanks for the advice in advance.