For you LS lovers :)
#1
For you LS lovers :)
I recently read a article from Hot Rod magazine where they took a 5.3L truck engine to see how much boost and power the stock bottom end could take and it came with a twist, but that's for later.
Their guinea pig:
5.3L truck engine
A pair of 76 mm turbos with a homemade plumbing system and air-to-water cooler
Rust spot in No. 8 cylinder
The bottom end was left completely untouched with the exception of the top rings being gabbed to .028 over the .015 stock. The heads were ported and got larger intake valves with matching springs. ARP studs for the heads and a cam change with new lifters but stock push rods and rockers. The intake was swapped to a LSXR intake, 75 lb/hr injectors and a 102mm TB.
Without the turbos, the 5.3 made 451 HP and 380 lb/ft of torque.
The engine was maxed out @ 26.8 lbs of boost and made 1203 HP. It made 60 runs, most being over 1000 HP and straight up to 6500 rpm.
Think that was the surprise? Guess again. When Hot Rod had the heads off they noticed it had flat top pistons. After the dyno runs they realized that 5.3L rarely came with flat tops. It turns out that after pulling the oil pan off and looking at the connecting rods (121) and crank for casting numbers (12553482), it was determined that the 5.3 wasn't a 5.3 but instead a 4.8L. For 294 cu. in., it made 4.09 hp per cu. in.
Their guinea pig:
5.3L truck engine
A pair of 76 mm turbos with a homemade plumbing system and air-to-water cooler
Rust spot in No. 8 cylinder
The bottom end was left completely untouched with the exception of the top rings being gabbed to .028 over the .015 stock. The heads were ported and got larger intake valves with matching springs. ARP studs for the heads and a cam change with new lifters but stock push rods and rockers. The intake was swapped to a LSXR intake, 75 lb/hr injectors and a 102mm TB.
Without the turbos, the 5.3 made 451 HP and 380 lb/ft of torque.
The engine was maxed out @ 26.8 lbs of boost and made 1203 HP. It made 60 runs, most being over 1000 HP and straight up to 6500 rpm.
Think that was the surprise? Guess again. When Hot Rod had the heads off they noticed it had flat top pistons. After the dyno runs they realized that 5.3L rarely came with flat tops. It turns out that after pulling the oil pan off and looking at the connecting rods (121) and crank for casting numbers (12553482), it was determined that the 5.3 wasn't a 5.3 but instead a 4.8L. For 294 cu. in., it made 4.09 hp per cu. in.
#4
Pretty much. But either way, that's a lot of power for a stock engine to take. I love my LT1, but I don't think it could take that kind of abuse without something breaking. Which really leads me to wonder how my cousin put a rod through his WS6...
#6
^ That's probably what he did. I wonder if I still have pics of the engine.
Edit: I went back and found the pics. He didn't put a rod through the block, but he did bend it pretty bad. And his car was N/A but knowing him, he did probably run it a little hard.
Edit: I went back and found the pics. He didn't put a rod through the block, but he did bend it pretty bad. And his car was N/A but knowing him, he did probably run it a little hard.
Last edited by MKCoconuts; 07-09-2012 at 12:49 PM.
#8
Wow lucky do you know what other damage was done.
#9
And frankzlt1, I don't remember if there was any other damage. I do remember though that the engine that rod came out of was still running fine when he pulled it, just didn't have the power he wanted so he was pulling it to switch to a all ready built LS when he discovered that.
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