I have a 4 bolt main 350 block at my disposal

And a camaro with a tbi 305 that needs to take a hike

So I was thinking completely overhaul the 350 and tuned port it

throw it in my car

What am I looking at here as far as price, anyone with experiences like this?

 

On the cheap? $1500

The most it's going to cost? The sky is the limit!

 

Do you already have the TPI?

What heads are on the 350? Or is it just a shortblock?

 

No I don't have the tpi already
But I have a friend with a setup and he willing to sell for cheap
And it does have heads on it, I don't know what heads they are, its from an 89 Chevy Truck, haven't looked at it too much.
Its a complete engine, tbi, truck is a rust bucket and has some electrical problems not really worth fixing, but I believe the engine is worthy of my car.

 

Both your engine and the '89 truck engine have swirlport heads. Okay for what they are, not the best basis for power improvements.

There wouldn't be a big advantage going to TPI if you keep the swirlports. It would work, but the expense of the conversion probably wouldn't be worth it.

 

I was actually looking at new gmpp aluminum zz4 heads

 

Don't forget to put the machine shop in your budget. You need to have your lifter valley machined for the roller lifters if your truck engine didn't get them. Some did/some didn't. Your block is the proper casting to have them machined.

 

Probably not worth it to machine a roller casting block that isn't machined for the roller components. It's more than the lifter valley, the cam retainer won't be machined/drilled/tapped, either.

The GMPP/Vette/ZZ4 aluminum heads are okay, certainly better than swirlports, but don't have the exhaust cross-over passages. So, you'll either have to plumb exhaust gases up to the intake manifold, or delete EGR from the PROM. If you delete EGR, you'll have to modify timing tables as well.

Any idea what the TPI is off of? What cam are you planning on running?

 

The tpi is off of a 88 Iroc
no idea on the cam yet
What heads would you suggest, because I've yet to get any parts, anything can be changed

 

It really depends upon your ultimate goals. If you could get the heads the TPI came off of, they would be fine for a lot of power. If you want new, the GM aluminum will be fine. Keep hearing they do a lot better with a little port clean-up work.

'88 TPI will be MAF, which is a good thing for mild changes. If you want to start making serious power, it'll be a limiting factor.

 

I'm kinda thinking mild and cheap for now

maybe looking a little more extreme later on down the road though

but the tpi is cheap and I could swap it out later if I want to go more extreme

how limiting would it be?

 

The stock runners limit RPM power to 4500. By that I mean their length is tuned such that it maxes out at 4500 RPMs. They also restrict flow. Stock swirl port heads wouldn't hurt you here.

The first step is aftermarket runners that are shorter and fatter. This will raise the powerband to a higher RPM, and allow better flow.

The base is the next limiter, it can be ported to work pretty well. Ditto the plenum.

You can get very nice street-friendly power with those mods and a well-chosen cam.

 

Actually the plenum is already ported and they are aftermarket runners, slp if I'm not mistaken.

 

Sounds like you're in good shape, then.