TBI to Vortec head question

[willy]

Ok, so I know I have seen some posts about a TBI to Vortec head swap on here, but I just get into more of a fog on the whole idea when I read them. Some people say they swapped the heads and intake with no issues, then some say that it ran like crap. So, I have a few of questions about it. I have a 1995 k1500 305 tbi. If there are any good threads out there that are clear, a link would be appreciated too.

1. What do I need to do it? I know I need the heads, but what would I need if I want to use my EGR vs. not using it?

2. Say I do the same swap on a 350 with 350 heads, do I need the same things as the above question needs?

3. Would doing an EGR delete have a crazy affect on my fuel economy or power?

4. Are there any intakes that allow me to use the EGR? I'm ok with getting an adaptor plate, if need be

5. If I am able to use the EGR, is it necessary that I get a tune too?

Part numbers are appreciated whenever possible. Thanks!

 

[mistaake]

Is there a point at which it would be easier to throw a whole 350 in replacement of the 305? Seems like a popular choice to do that. Then throw the mods required to get up to the power you want... unless you need the original engine for smog test requirements or something.

 

[willy]

I would love to swap to a 350, but I don't exactly have the means to do a motor swap, so I was hoping to get some info on a vortec head swap, and do that to gain some power out of my 305.

 

[96-1500]

1. What do I need to do it? I know I need the heads, but what would I need if I want to use my EGR vs. not using it?

Google GMPP manifold. Pretty expensive, but it's basically a bolt up manifold for running TBI and Vortec heads. There are lots of other adapter manifolds but I've personally never seen any others that accept EGR (not saying they don't exist, I just haven't seen them). You can go without EGR if you choose. There will be an engine light unless you have it tuned out of the computer (see below, however...)

2. Say I do the same swap on a 350 with 350 heads, do I need the same things as the above question needs?

Yes.

3. Would doing an EGR delete have a crazy affect on my fuel economy or power?

No.

4. Are there any intakes that allow me to use the EGR? I'm ok with getting an adaptor plate, if need be

See said GMPP manifold

5. If I am able to use the EGR, is it necessary that I get a tune too?

You'll need a tune regardless. It will run without one, but not well.

I would love to swap to a 350, but I don't exactly have the means to do a motor swap, so I was hoping to get some info on a vortec head swap, and do that to gain some power out of my 305.

Personally, I wouldn't put much money into a TBI 305. I run one in my K2500, it works great, but it was never really designed to be a powerhouse. Squeezing a little more power out of a 350 is going to be a much more enjoyable endeavor IMO.

That said, do what you can with what you have, and be sure to post up your results!

Sent from somewhere between here and there

 

[willy]

Google GMPP manifold. Pretty expensive, but it's basically a bolt up manifold for running TBI and Vortec heads. There are lots of other adapter manifolds but I've personally never seen any others that accept EGR (not saying they don't exist, I just haven't seen them). You can go without EGR if you choose. There will be an engine light unless you have it tuned out of the computer (see below, however...)


Yes.


No.



See said GMPP manifold



You'll need a tune regardless. It will run without one, but not well.



Personally, I wouldn't put much money into a TBI 305. I run one in my K2500, it works great, but it was never really designed to be a powerhouse. Squeezing a little more power out of a 350 is going to be a much more enjoyable endeavor IMO.

That said, do what you can with what you have, and be sure to post up your results!

Sent from somewhere between here and there

Thank you, its good to finally get a straight answer. I might just wait for the motor to blow, then upgrade to a 350, then start adding things like heads, intake, and other goodies. the truck is really a daily driver, but I'm trying to fix it up and make it all pretty, and one thing that bothers me is how gutless the 305 really is.

 

[96-1500]

Thank you, its good to finally get a straight answer. I might just wait for the motor to blow, then upgrade to a 350, then start adding things like heads, intake, and other goodies. the truck is really a daily driver, but I'm trying to fix it up and make it all pretty, and one thing that bothers me is how gutless the 305 really is.

You're in exactly the same boat as me. I can't justify pulling a perfectly good working engine - but it's so embarrassingly gutless. I was hauling wood with it this fall...half a cord in the bed and half a cord on the trailer. I had a hard time getting up little hills.

Once she pukes a rod through the block, 350 will go in and I'll never look back.

Sent from somewhere between here and there

 

[willy]

You're in exactly the same boat as me. I can't justify pulling a perfectly good working engine - but it's so embarrassingly gutless. I was hauling wood with it this fall...half a cord in the bed and half a cord on the trailer. I had a hard time getting up little hills.

Once she pukes a rod through the block, 350 will go in and I'll never look back.

Sent from somewhere between here and there

well, its a slow boat, lol. I mean, I'm not looking to get a drag racer out of my truck, but it would be nice to be able to be at highway speed when I get to the highway. Although I don't have any complaints about how mine hauls, I pull a 17ft walkthrough, which weighs in at roughly 1000lbs (not like I'm pulling a tank), but it does pretty good with that.

But yeah, definitely getting a 350 as son as the 305 blows.

 

[TylerZ281500]

i didnt read any of this buttttt. carb intake, vortec bolt pattern and use a spacer for the tbi better than the gmpp etc and can be had for around 140 all day long. i however would not put 350 heads on a 305, wont benefit you enough and youll have to probably shroud the chambers due to bore differences

 

[Jorge6.5]

From what I've read, 350 vortec heads that have been shaved down work well on 305s. A good cam is a must

 

[willy]

Wow, thanks for al the responses. If there was any confusion in what I'm doing, I'm sorry I wasn't more clear, but I would like to put 305 vortec heads on my 305.

Another question: Is there any specific casting numbers I should look for? Or can I just tell the cylinder head guy I want 305 vortec heads?