vortec head question

[notfastenuff]

Hi everyone.
Well, my choice of doing an LS swap is gonna have to wait ($$$, I gots none), so I'm exploring options on putting a band aid on my 305 Vortec.

I've got what I'm assuming is a burned valve on cyl. 6. It has a whopping 30 psi of compression. The plug was soaked with oil as well. I'm gonna pull the heads and look into having them reworked, but I also know that a lot of people end up with cracked vortec heads. So, I'm keeping my options open.

My biggest question is: If I have to buy replacements, how well would the 5.7 (350) heads run on my 305? I found threads about 305 heads sucking on 350s, but nothing about the other way. Does anyone have any other suggestions?

Thanks!

 

[woody80z28]

You will lose compression by slapping 350 Vortec heads on your 305, but you can minimize the loss by using a thin head gasket. I put .015s on my 357 to bump compression.

The 96-98 Vortec era 305 heads do not have the same combustion chamber as the 350 Vortec heads. They actually act more like a swirl port head. So what you lose in compression, you may gain back and then some with the added flow of 350 Vortec heads.

However, you may be able to find a full 350 Vortec engine to swap in place of your 305 pretty easily.

 

[notfastenuff]

However, you may be able to find a full 350 Vortec engine to swap in place of your 305 pretty easily.

I tried this first thing. The nearest one to me is over 400 miles away according to the parts locator service my local yard uses.

Thanks for the head info. That's exactly what I was wanting to know. This is kinda my worst case scenario. I'm just trying to bandaid this thing along until I have the money to swap it.

BTW, I love your sig pic. You've got some nice rides.

 

[scmsltn]

I tried this first thing. The nearest one to me is over 400 miles away according to the parts locator service my local yard uses.
QUOTE]

Are you kidding....search craiglist and you will find a bunch of vortec 350's or people parting out tahoes, yukons, sierra, etc!

 

[notfastenuff]

I tried this first thing. The nearest one to me is over 400 miles away according to the parts locator service my local yard uses.
QUOTE]

Are you kidding....search craiglist and you will find a bunch of vortec 350's or people parting out tahoes, yukons, sierra, etc!

No, there really aren't. Found one Tahoe part out, but considering that they didn't take enough care to keep the trans in it, I don't think that I want the engine. I don't live near a major metro area, so there really aren't that many. Feel free to search the Knoxville and Tri-cities, TN CLs if ya don't believe me.