need a head tutorial pros/cons, new, rebuilt, etc...

[aggiedave98]

Ok, I'm still doing research on building a 383 this fall for my '89 suburban 1/2ton 2wd w/ a 350 (currently).

A lot of my research was reading David Vizard's books like "How to Build Horsepower" etc... HP on a budget...

In one of the books he has 10 engines that he has built w/ pretty impressive numbers... in most cases he has rebuilt the heads.

I've heard folks here say to buy new heads b/c a rebuild was too expensive, but for a 383 for towing is that right?? Vortec heads at jegs are about $1200/pair.

I also had my machine shop guy (I haven't used him yet, but stopped by to get to know him and tell him what I was planning on doing... he's the owner of a 30-year old shop and sounded like a great guy) tell me that I'm better off rebuilding the heads than going w/ vortec b/c they're not as durable etc (can't remember what else he said about why the original were better).

So I'm a little stuck about what heads I should use... I'm not as concerned about money because I'm treating my suburban as a heck of a lot cheaper than buying a new one (or even a used one) when you put in there a 10% drop in value per year and a $40k price new...

I know there's a lot of questions here, but I'm trying to figure out who to listen to about heads:

1) david vizard (rebuild old heads)
2) machine shop guy (rebuild old heads)
3) what seems to be common thoughts here and everybody else I know (new heads)

A key piece of info is probably that I want this mainly for everyday driving and towing. I have a 3" lift and 32" tires so I'm not going for the dragstrip here...

thanks!

[aggiedave98]

One other question is that David Vizard talks about 186 heads being good for rebuilds... what heads do I have in my '89 suburban?? how do I find out?

[70c10]

I would not build your 89' heads. I would go with Dart Iron eagles if you are on a budget or even Vortecs. I'm not sure why jegs wants so much for Vortecs. Should be around $550. If you are going to run a cam with over .480 lift you will have to have the heads setup for that. I doubt you are since this is a tow vehicle. Scoggin Dickey sells vortecs and intake packages:http://www.sdpc2000.com/catalog/2172...-Head-Kits.htm

[RunTMCfan]

Since weight is not a concern (not racing) you can go with a cast iron head instead of an aluminum head too. That will save you some $$$ as well. All you are really chasing are bigger valves. For most people 2.02 and 1.60 valves are what you will need.

I havn't bought heads in years. But when aluminum was $1300 the cast were about $850.

Back in the day aluminum heads were known to shift a little as well. Bolting two different metals together (cast block to aluminum heads) was not a good fit. Now I'm sure that's not a problem.

Just some random thoughts I had.

[shadetree]

To rebuild, or NOT to rebuild, that is the question. I've read a lot of Vizards books, the guy is very good, but try to consider the entire package here. If you "rebuild" your old heads, will you: replace the valve guides, replace the exhaust seats (they are only "surface" hardened from GM), new exhaust and intake valves, new valve springs, new valve locks, new valve seals, mill the heads, and do some "pocket porting"? If you do all that, you should have right smart the cost of new Iron Eagle heads.
So, a new question should be: "do I really need all that stuff Shadetree listed"? If you short cut that list, you will be sacrificing some ammount of quality to cheapen the end product. Take valve springs, for example, sure, your freshly rebuilt engine will run with those old springs. If your machinist shims them properly, they should be good for another 50,000 miles. But, the redline you chose should reflect a lower ceiling. If you ever over-rev, your engine might injest a valve. If you will never rev above,,,say about 5,000 rpm, you should be OK. But, you still have given up something to save money. The new heads have all that listed stuff, new. Also the new heads flow good, right out of the box. The new heads also feature much better combustion chambers.
None of the above listed stuff needs to be done, if you are willing to settle for what you will get for not investing. It's your truck/time/money, you get to chose.

[aggiedave98]

Thanks guys! I will take a look at all the suggestions. Based on what you've said, I'll go new... I want to do it right, so I'm not going to cut corners to save a few bucks. I plan on keeping the truck a really long time, so it will pay off.

[Tom]

$1200 for vortecs in jegs is what they call "aluminum vortecs" which are actually fastburn heads. 2.00/1.55 valves, 210cc intake ports [bad for suburban and torque] and they flow completley different then the iron L31 vortecs. They also have 200cc port iron vortecs, but those flow like the fastburns. Standerd vortecs are still $500 a pair.

Vizard made power with those heads because he is a porting guru....

[lownfast]

go new modified vortec for bigger lift cam, under $600 is well worth it.