How to tell if I have aftermarket Heads?
 

Hey guys,

I was looking through the list of mods from when I bought my car.. The previous owner didn't list heads. I found an ad for my car (definitely my car) here on LS1Tech, and it lists 5.3 Stage II heads. If I go out and look at my car how could I tell if I do have them or not? I believe aftermarket heads are taller right? It's kinda confusing not knowing whats in my car exactly lol.

Or what if I grabbed a pic for you guys..
Thanks!

You can look at the casting number on the corner of the head to see what they are but you won't know what's done to them unless they have another identifying part number or you remove them from the car.

You can find the casting numbers and see what they match up to if they are factory castings. Also, many (maybe all?) aftermarket heads are ID'd by the manufacturer. My dart's have this on an emboss on the outer corners of the heads.

its going to be tough to tell, especially if they are stock casting which are ported. AFR and Patriot and other companies do engrave their heads, but I know my ported 243's from TSP didnt say anything on them, except the back had permanent marker writing on it

Pull off the intake and look at the runners....

5.3 Stage II heads will be GM castings...go out and look at the drovers side head, on the front corner of the head (right next to the valvecover) there will be a GM casting number (same number should be on the back of the passenger side head...and you probably won't be able to see it)...based on your name, I'm guessing your car is a 98...that being the case, your stock heads were perimiter bolt valvecovers and the casting number should be 806. 5.3's are probably going to be 706...unless they came off a much newer 5.3 in which case I don't know...they will be centerbolt valvecovers though.

At the very least...if you identify them as 5.3 heads (from a truck) you will then know they're not your cars stock heads...you won't really know if they're ported without some dissassembly to see, but I'd say it'd be a good guess. Removing the intake isn't too bad...few hours worth of work to remove and reinstall...but make sure you don't overtighten the intake manifold bolts when you reinstall.

Whats done to the car? Post up some pictures of the engine bay.

The car is actually a 99.. (made this account when i made a deposit on a 98 then the dealer sold it under me) and it has 400+RWHP. i don't have any good pics that show the heads, but I have a few of the engine. After I eat i'll probably head to the garage, take a look, and grab some more pics to show you guys.

This one's the best outta the ones I have
http://i11.photobucket.com/albums/a1...g?t=1231637317
http://i11.photobucket.com/albums/a1...x/DSC02549.jpg

clean car

Not to try to hijack, but what would the casting numbers on an 01 head be?

241 .

I think I told you to look at the wrong head....now I can't remember if it's going to be easier to see on the passenger side or drivers side...sorry. I'd run outside and look at mine...but the snow is falling fast out there.

VERY clean car...you must be proud. EGR is gone too so you probably have an LS6 intake on there...I really doubt it's an early C5 LS1 intake.

its the passenger side that its visible on

The number you're looking for will be right here.

Thank you very much for the comments guys :) Yup the EGR is gone and it's an LS6 intake. I'm going to run outside now and look. It's snowing here too but luckily I have the car garaged at a neighbor's house. Be right back! I'll get some pics

So what'd you find?

very good explaination for him, for referance, my PRC 2.5 5.3's used a 862 casting.

And it issss... 862! sorry i took so long i ended up having to move some cars out (which just gives me an opportunity to drift around in the snow :D) and shovel for a bit.

Here's the pics.. Tight spots are a little dirty :(

http://i11.photobucket.com/albums/a1...x/DSC03030.jpg
http://i11.photobucket.com/albums/a1...x/DSC03031.jpg
http://i11.photobucket.com/albums/a1...x/DSC03035.jpg

1. so what does this mean!
2.. Anyway to fix the headers, lol?
3. What's the casting number in the 3rd pic mean

huh im curious what these heads are?

Im looking at the piece of paper I wrote it down on..
"Speed Stage II 5.3 Heads"

I'll find the old LS1tech ad from previous owner's ago

1. it means you definately have 5.3 heads on your car :)
2. depending on how deep the rust is steel wool should clean up a lot of the surface rust(works on my pacesetters anyways)
3. no idea, maybe a date code or something