New heads or new long block?

[English]

Some opinions please!

Truck needs some love in the engine department. I'm wondering which direction to take. I either have a blown head gasket or a cracked head. Also my vacuum gauge tells me I have worn valve guides. It's a 350, 165hp

Wondering what the pros and cons are of replacing/rebuilding the heads vs swapping in a long block. Also I'd like to install the Comp 12-300-4 (because of my existing motor has the heads and manifold off, I might as well put the cam in; and if I'm putting a new block in, I might as well put the cam in the new engine before dropping it into the truck).

Working out the costs, going down the new long block route costs an extra £1,000. And changing the cam *might* void the warranty (over here the warranty will be upheld by the vendor, it's not worth sending a block back across the pond to GM).

What are the pros of using a new long block, and what are the cons of using my existing block?

[enaberif]

When I got my truck the engine is completely unknown with unknown mileage.

All I did was put new heads, cam, lifters, and push rods in. I haven't done a compression check yet but the truck runs amazing for what it is and doesn't blow any blue or black smoke ever. But the amount of money I've put into it so far I could have saved a few hundred more and dropped a new long block in.

To be honest with the cheapness of a long block these days it really doesn't make much sense to toss a bunch of money into an older block.

[rich weyand]

^^^ agreed.

[English]

Right, after a whole lot of thinking I've decided to go for a new long block 
A lot of money, but I'm hoping it will be a "wise" spend that adds value to the truck. And the old girl is in otherwise such good condition that I think she deserves it.

Question- it'll be the 350/260 that I'm getting. I've read up a whole lot on the 260 vs the 290, and the 260 sounds much more appropriate as it has better low down torque. But... would it be a good idea to swap the cam out before the block even goes in? It would be the Comp Cams 12-300-4 that I'd go for. I've been reading Rich Weyands threads, and the 12-300-4 sounds ideal, but at the same time I'm wondering if the benefit would be worth it over the stock 260hp, as pretty every thread I've read about the 290hp concludes that it's a rev-hungry low torque set up.

Should I swap the cam out straight away, or see if the stock 350/hp is good enough as it is?

I have Flowmaster true duals, Edelbrock Performer intake, and Holley 570cfm carb. Unfortunately I can't use the Comp Cams dyno software as my laptop is a Chromebook and my work PC blocks it. If anyone fancies plugging in some numbers on my behalf I'd be very grateful!

[Engineer]

+1 for the long block.

[LTZ C20]

+2 for long block

[English]

Yeeeeeah I'm going for the long block already! Now wondering about the cam

[LTZ C20]

If you want bone stock, as close to original, as you can get, don't add performance parts. If you want extra HP or extra torque or to use existing parts that you stated above, then you will have to make sure they are applicable to the new long block.

Also, alot of long blocks come with a warranty, the moment you pop ONE bolt loose that's not required for final engine assembly then your warranty is void. If your ok with that then that's ok, but if you like to retain the warranty, consider finding a company that builds long blocks with customer request parts. That way you can tell them what you have and what you want and then you win both ways.

[English]

It's a tricky one. On the one hand I don't actually need the truck to be *fast*, but on the other hand I don't want to drop a new motor in and be disappointed with it's performance. On the flip side, I don't want to spend out on changing a cam if it's not necessary (the company that sells the block can swap the cam, but would charge 3-4 hours labour, is that right?), and risk the warranty in the process.

[Kren420]

I would run the new engine for a while, then you can find exactly what you would like to improve, if anything.  That and I wouldn't want to void any warranty you might have.

[LTZ C20]

There are a number of companies that build engines per customer request. You could call a few up, tell them what you want, price around a bit. I bought my short block from a company called ATK Performance Engines. They build short blocks, long blocks, performance turn-key engines and can add curtain parts you want so you don't have to add them your self. Since they are assembling the engines, the work should be covered under there warranty. Most shops like this use stock parts for stock engines and well as popular performance brands parts. It's gonna take some shopping around but you should be able to find what you want.

[English]

There are a number of companies that build engines per customer request.

Ahem, permit me to draw your attention to my username sir. I'm in the land of your forefathers! Not quite so easy over here I'm afraid. There are a few places that do builds, but they're way out of my price bracket. The company that I'm planning on getting the longblock from want £300 just to change the camshaft. That's with an engine that's not even in a vehicle!

I think I live in the wrong country 

[LTZ C20]

There are a number of companies that build engines per customer request.

Ahem, permit me to draw your attention to my username sir. I'm in the land of your forefathers! Not quite so easy over here I'm afraid. There are a few places that do builds, but they're way out of my price bracket. The company that I'm planning on getting the longblock from want £300 just to change the camshaft. That's with an engine that's not even in a vehicle!

I think I live in the wrong country 

I didnt forget, I just wasn't sure how you were planning on getting or doing all of this so I just threw the ideas out anyway. Some of it may or may not be useful.

On another note, my mother was born is Sydney, Australia. So I'm half part of the people who got kicked out of the land of my forefathers.

[Engineer]

I would try the 260 before swapping in a cam. Especially if it will void the warranty.

The 454s of the era of our trucks were only 230hp, but they were also 380tq. The 260hp 350/5.7 should move the truck around quite respectably especially considering that the truck has a manual transmission.


And as an additional thought I'm predicting English will soon be wearing Levis, cowboy boots, a New York Yankees baseball cap, and listening to 80s Southern Rock........once you've been bitten by the bug......

[English]

There are a number of companies that build engines per customer request.

Ahem, permit me to draw your attention to my username sir. I'm in the land of your forefathers! Not quite so easy over here I'm afraid. There are a few places that do builds, but they're way out of my price bracket. The company that I'm planning on getting the longblock from want £300 just to change the camshaft. That's with an engine that's not even in a vehicle!

I think I live in the wrong country 

I didnt forget, I just wasn't sure how you were planning on getting or doing all of this so I just threw the ideas out anyway. Some of it may or may not be useful.

On another note, my mother was born is Sydney, Australia. So I'm half part of the people who got kicked out of the land of my forefathers.

Ah sorry, I thought you had assumed I was in the US.
Everything's do-able over here, just a lot more expensive. For example, the same long block that costs $1500 from jegs is going to cost me $2800.

Apologies for the Botany Bay thing, I think people got kicked out just for stealing apples, cor blimey guv'nor!