2.8 Performance Upgrades
2.8 V6 (RWD 82-85) RPO: LR2 VIN: B
Engine Description (LB6) 2.8L 60 degree V6 (Carbureted)
Horsepower (HP@RPM) 110@4800
Torque (ft-lbs@RPM) 148@2000
Block Cast Iron
Heads Iron
Valves 12
Displacement 2.8L (2800cc, 173ci)
Bore 89mm (3.503")
Stroke 76mm (2.992")
Compression Ratio 8.5:1
Intake / Exhaust valves 1.60" / 1.30"
Valve lift .347" / .394"
2.8 V6 (RWD 85-93) RPO: LL2 VIN: R
Engine Description (LB6) 2.8L 60 degree V6 (TBI)
Horsepower (HP@RPM) 125@4800
Torque (ft-lbs@RPM) 150@2400
Block Cast Iron
Heads Cast Iron
Valves 12
Displacement 2.8L (2800cc, 173ci)
Bore 89mm (3.503")
Stroke 76mm (2.992")
Compression Ratio 8.9:1
Intake / Exhaust valves 1.725" / 1.425"
Valve lift .393" / .410"
Cam specs on 2.8 TBI pushrod motors:
Stock Cam:
Centerline ATDC = 109* on both sides
Duration at .50 = Intake -196* exhaust – 203*
Max lobe lift at .50 = intake -.263* exhaust -.273*
Rocker ratio = 1.5
Gross lift = intake .395” exhaust -.410”
Lobe separation =109*
Source (https://www.s10forum.com/threads/2-8-and-60-v6-performance-mods.520930/)
Performance Mods
A. Build a cold air intake. Parts are available on Ebay.
B. Bore the intake openings and install a larger TBI assembly. You can also install a manual fuel pressure regulator for increased pressure.
C. Advance timing to approximately 12* to 14* base timing. If the engine detonates, retard accordingly, although I think that 14* will be fine.
D. Make sure there are no restrictions in the exhaust system – particularly the cat.
E. Install an electric fan and controller.
F. Check that all tune up components are at peak efficiency. Change your oil @ 3K miles.
G. Make sure your tires are properly inflated – I run 30F and 35R.
Catalytic Converters
A. Install a larger cat back exhaust system. 2 ¼” to 2 ½” is good. The larger will give top end, the smaller for lower/mid-range power. There are many systems available for these trucks through Jeg’s and Summit.
B. Install a high flow cat at least 2 ½” in/out. For the 2 ¼” use reducers at both ends. You can eliminate the cat, but I don’t recommend it due to emission laws.
Headers
A. Install a set of headers and run a large Y merge pipe for the exit, unless you run dual exhaust.
2 ¼” pipes from the headers to a Y pipe into the cat is the trick.
Cam
A. It’s cam time! Select an aftermarket cam with about .480 lift and .285 duration with a 10* or 12* lobe separation. You will also need new lifters. You can go with less lift/ duration but this is about right for a good power punch. Install a TRUE ROLLER double timing chain. Cloyes makes them for this application. Note how stretched the old chain was. The new unit will not stretch as quickly.
Roller Rocker Arms
Install a set of roller rocker arms. These are not cheap, but it’s the last bolt on that you can do. They come in 2 varieties. 1.6 and 1.5 ratio (stock). The 1.6 will give more lift and a little more power.
Source (https://www.s10forum.com/threads/2-8-and-60-v6-performance-mods.520930/)