Thunor

Hello everyone,

I'm slowly piecing together my rust bucket rat-rod looking 79. I have an L48 with a 4 speed and I have come across people saying that vortec heads are a good affordable set of heads that can accommodate upwards of 450 HP. I just heard of them yesterday, so I am pretty ignorant. My ultimate goal is just to get 400 HP out of this engine over time.

I'm going to go junkyard hunting soon and the vehicles that these heads were put in are in plentiful supply at my junkyard, but won't they have port holes for fuel injectors? If they do, can I still use them? And, is it possible to mod the intake or the heads to mate properly so I don't have to buy another one?

Here's a list of the stuff I've already done to my car's engine (keep in mind this is my first muscle car and I've only been tinkering with it for a short while):

Timed the engine to 36 degrees like everyone said to do and put some baby springs on the distributor's weights
Bypassed/deleted basically all the emissions stuff
Made some side pipes out of cherrybomb glass packs and hooked up some hooker headers that came off a 94 corvette

Goal with my car is to prep it up for fun on the autocross course (I get like 71st place out of 78 in my BMW which is better than probably half the cars there, so I'm just out there to enjoy myself lol ) and it will definitely be my daily driver.

L88Plus

Forget the junkyard search, you're likely to buy heads that are either cracked or otherwise damaged. Most will charge you like they're made of platinum.
The casting numbers you 're looking for will end in either 062 or 906. Either will work fine. Injectors are inside the factory intake, there's no holes for them in the heads. That didn't start until the new generation of LS engines with direct injection.
A little time spend blending the bowls and the ridge on the short turns will really help airflow. No reason for larger valves, stock size will be just fine.
If you have a good local machinist that you trust, see if they have any on the shelf, most do.
Where are you located? I have a couple of pairs and would let go of a pair if you can't find any.
And don't try to use a manifold that has been re-drilled, it's such a hit and miss that it's not worth the time. Get a dedicated Vortec intake. Bolts are straight up and down rather than angled when installed. I'd get the tallest dual plane that'll fit under your hood. Ebay can be your friend, just make sure if you buy a used one that you get a guarantee from the seller (and use one with high positive feedback) that there is no damage, no stripped bolt holes, etc.

derekderek

Also new vortec heads are reasonably priced.

AboveTheLogic

Rescue Rogers

make sure the rocker arm studs have been converted to screw in studs vs the press in studs

jb78L-82

As others have said, buy a new set of cast iron vortec heads for $700 or remanufactured completely rebuilt vortecs for about $450 for a pair. I would not waste time with junk yard used vortecs that will most likely need work anyway..........

If you are looking for 450 Gross HP from a base L48 motor using vortecs, I think you may want to lower that HP goal a bit......Vortecs will give you about 30-40 more Gross HP than the OEM heads with the correct cam and compression (at least 9:1). If your target gross HP is 450 Gross HP you will need what my L-82 355 has:

AFR or similar top quaility cylinder heads
>10:1 compression (mine is 10.2:1 AND runs with zero detonation on 89 octane fuel)
Roller cam with at least .525 lift or greater

This ^^^^ will get you 450 Gross (not net) HP.