Are there different versions of the Pontiac 151?
Now Pontiac has made several different versions of the 151 with all sorts of changes over the years which has caused lots and lots of confusion. They built “2”, “5”, “R”, “U”, “E” and “A” code engines (I may have even left out a few).
What are the dimensions of a 1978 Pontiac 151 Iron Duke?
Part # is 1539 (1978 Pontiac 151 Iron duke) (all same dimensions as Pontiac 301 v8 pistons). Standard 4 inch bore 1.57 compression height Pin Diameter 0.9273 Rings: 2 – 5/64 1 – 3/16 KB-silvolite Pontiac 2.5 Engine Block Information 2.5L 151 c.u.i. 92-hp 4 cylinder “Iron Duke” – Pontiac 4.00 inch bore x 3.00 inch stroke.
What are the Rockers on a Pontiac 2.5?
Pontiac 2.5 Rocker Info Your best solution is Crane Aluminum Roller Rockers: Ratio: 1.71 Stud Diameter: 7/16″ Part Number: 22750-8 Stock Ratio for the 2.5 L is 1.75 These will reduce valve lift a small amount accordingly. These are the same parts used in big block chevy engines only eight of them instead of sixteen.
What kind of Head do I need for Pontiac 2.5?
Pontiac 2.5L Heads Stock heads “swirl-port” intake ports are restrictive. Either port the stock intake ports or use a Super Duty head. If your rule book requires a stock head with no porting or polishing, consider the Super Duty head. It has a GM casting number. All Super Duty heads use 1/2 head bolts.
Now Pontiac has made several different versions of the 151 with all sorts of changes over the years which has caused lots and lots of confusion. They built “2”, “5”, “R”, “U”, “E” and “A” code engines (I may have even left out a few).
Part # is 1539 (1978 Pontiac 151 Iron duke) (all same dimensions as Pontiac 301 v8 pistons). Standard 4 inch bore 1.57 compression height Pin Diameter 0.9273 Rings: 2 – 5/64 1 – 3/16 KB-silvolite Pontiac 2.5 Engine Block Information 2.5L 151 c.u.i. 92-hp 4 cylinder “Iron Duke” – Pontiac 4.00 inch bore x 3.00 inch stroke.
Pontiac 2.5 Rocker Info Your best solution is Crane Aluminum Roller Rockers: Ratio: 1.71 Stud Diameter: 7/16″ Part Number: 22750-8 Stock Ratio for the 2.5 L is 1.75 These will reduce valve lift a small amount accordingly. These are the same parts used in big block chevy engines only eight of them instead of sixteen.
Pontiac 2.5L Heads Stock heads “swirl-port” intake ports are restrictive. Either port the stock intake ports or use a Super Duty head. If your rule book requires a stock head with no porting or polishing, consider the Super Duty head. It has a GM casting number. All Super Duty heads use 1/2 head bolts.