5.3 Liter Engine specs
#1
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On The Tree
Joined: Oct 2002
Posts: 137
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From: mcallen, texas, usa
Is there a place that can tell you the specs of your engine. I want to know cam size, if we have roller rockers (size), roller lifters, lift duration. displacement, heads and stuff like that for a 2000 5.3
#4
The stock cam is tiny, around 200/203 dur .46x" lift, I think. Not as puny as the one in my F-150: 180/183 ~.400" lift. It is really crappy! Peaks at: 185hp @ 3800rpm/270tq @ 2700 rpm!
Anyway, you have 1.7:1 rockers from the factory. They have a roller fulcrum (base) but not a roller tip. SLPs 1.85:1 are just a roller fulcrum too. Yela Terra are bad *** 1.8:1 shaft mounted full roller rockers (tip and fulcrum).
GM has been using roller lifters for a while now, I'd assume since the late 1980's. Your GenIII block does have roller lifters. They read the cam profile far better than flat tappet lifters and wear better too.
Displacement: 5.3 liters, 325 cubic inches, 3.78" bore x 3.62" stroke.
Heads are the 4.8/5.3 variants. They outflow LS1 heads but have smaller valves. 1.89" intake, 1.55" exhaust. I am not 100% sure on the exhaust valve sizing. They have about a 61-63cc chamber, these on a 5.7 GenIII boosts compression.
This is all from memory so the numbers could be/maybe/are slighty off.
Anyway, you have 1.7:1 rockers from the factory. They have a roller fulcrum (base) but not a roller tip. SLPs 1.85:1 are just a roller fulcrum too. Yela Terra are bad *** 1.8:1 shaft mounted full roller rockers (tip and fulcrum).
GM has been using roller lifters for a while now, I'd assume since the late 1980's. Your GenIII block does have roller lifters. They read the cam profile far better than flat tappet lifters and wear better too.
Displacement: 5.3 liters, 325 cubic inches, 3.78" bore x 3.62" stroke.
Heads are the 4.8/5.3 variants. They outflow LS1 heads but have smaller valves. 1.89" intake, 1.55" exhaust. I am not 100% sure on the exhaust valve sizing. They have about a 61-63cc chamber, these on a 5.7 GenIII boosts compression.
This is all from memory so the numbers could be/maybe/are slighty off.
#5
Here is some info on the heads to compare with.
99-2000 LS1 heads: #12559853 (for 99-00)
*66.67cc chamber
*200cc intake port, 2" valve dia
*70cc exhaust port. 1.55" valve dia
1999+ L59,LR4,LM4, and LM7: #12559852, 12561706
*61.5cc chamber
*200cc intake port, 1.89" valve dia
*70cc exhaust port, 1.55" valve dia
4.8/5.3 heads really don't offer any advantage to the LS1 heads other than the smaller chamber. They really need a larger intake valve.
Here is a site that might help you get some more engine info: GM poweretrain
99-2000 LS1 heads: #12559853 (for 99-00)
*66.67cc chamber
*200cc intake port, 2" valve dia
*70cc exhaust port. 1.55" valve dia
1999+ L59,LR4,LM4, and LM7: #12559852, 12561706
*61.5cc chamber
*200cc intake port, 1.89" valve dia
*70cc exhaust port, 1.55" valve dia
4.8/5.3 heads really don't offer any advantage to the LS1 heads other than the smaller chamber. They really need a larger intake valve.
Here is a site that might help you get some more engine info: GM poweretrain
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