CBIII

iTrader: (6)

Im not really sure what I have here since I really dont trust the person I bought the car from any longer (blown engine, blown tranny and other issues along the way)

The castings are 862 (4.8 according to the markings under an intake runner) but i imagine theyre aftermarket (maybe TSP)

The valves measure right over 2 inch (I assume 2.02)intake and just over 1.5in on exhaust (i imagine 1.60), the springs are a (dual spring) dark bronze but no other markings, the retainers are a bright silver. Ive got numbers all over the head but I dont know what they mean. Ill have pictures soon.





#B123 on the inside of the head



#S253(upside down 2??)32 on one end

#13163 on the other end

#0305217524838925 on the exhaust manifold side

slowjoe99

iTrader: (7)

are you sure the casting is 852?

CBIII

iTrader: (6)

positive. I took a pic but it gost lost in translation i suppose. it SAYS 4.8 on the bottom side of the runner (4.8/5.3 were the same) Why do you ask? I know the valves are bigger than what came stock.

thechad

iTrader: (4)

Casting Number 852
LR4
99+ 4.8L Truck
Material: Aluminum
Combustion Chamber Volume: 61.15cc
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 1.89 inches
Exhaust Valve Diameter: 1.55 inches

CBIII

iTrader: (6)

thanks..I guess I didnt make myself completely clear in my initial post.

Due to the oversized valves, portwork, springs/retainers, Im trying to figure out if anyone knows WHO did the work(numbers stamped into the heads) and WHAT the valvetrain components are.

5.3LJimmy

iTrader: (10)

They appear to have PRC springs, so they may be PRC heads. I have a set of stock 5.3/4.8 heads here and the only place it does not have numbers that match the location of yours are on the front and rear(like the 13163 on yours). My car is not here right now so I can't go look at my PRC's to see if there is anything there on them. I will take a look tomorrow and see if my heads to have something stamped on the fronts, but I don't recall seeing anything before.

CBIII

iTrader: (6)

What size are your valves? You mena yours has that number with an upside down 2 also, possibly?

thechad

iTrader: (4)

The ones that are dimple engraved (long number) are GM's, the sloppy digits hand stamped could be who worked on them after market, call everyone who does heads and run the number by them.

Livernosie, texas speed, et, .ect .ect ????

CBIII

iTrader: (6)

thanks. Theyre at least 4 years old, im not sure who else did them back then other than maybe TSP.

CBIII

iTrader: (6)

more input appreciated.

brad8266

iTrader: (23)

Use the 13163 hand engraved number and run it by all the well known ls1 head porters.

5.3LJimmy

iTrader: (10)

Mine don't have anything stamped on the front or rear. Valve sizes are 2.04/1.57.

CBIII

iTrader: (6)

interesting. we specd mine out to 2.065/1.55