The Difference Between a 413 and 413 Max Wedge Mopar Engines
Many people wonder about the differences between a 413 and a 413 Max Wedge.
A 413 Max Wedge engine was made for competitive racing while the standard 413 was produced for passenger vehicles. Although based on the same engine block design, the Max Wedge has more horsepower, higher lift cam, shorter cross ram intake manifold, higher flow cylinder heads, exhaust valves and exhaust manifolds.
The Max Wedge requires racing fuel while the standard 413 can use pump gasoline. This is due to the higher compression ratio of the Max Wedge. The 413 Max Wedge also has stronger internal components for durability and higher r.p.m.s.
This article will examine the differences between the two engines in more detail.
The Difference Between a 413 and 413 Max Wedge Engines
While both engines share the same engine block design there is many differences between the two Mopar engines.
The following table contains what is different between the Max Wedge and standard engines.
| 413 Standard | 413 Max Wedge | |
| Production Years | 1959-1965 | 1962 |
| Block Casting No. | 2120529 | 1852029 |
| Cylinder bore notches at top | No | Yes |
| Cylinder head ports | Standard | 25% larger |
| Cylinder head heat cross-over | Yes | None |
| Intake valves | 2.08″ | 2.08″ (More streamlined) |
| Exhaust valves | 1.60″ | 1.88″ |
| Valve springs | Single (16) | Dual (32) |
| Valve stem seals | Yes | None |
| Camshaft | .389″-.430″ lift 252°-268° duration | .509″ lift 300° duration |
| Tappets | Mechanical or hydraulic | Mechanical |
| Compression ratio | 10.0:1 or 10.1:1 | 11.0:1 or 13.5:1 |
| Intake Manifold | 2 x 4-barrel long cross ram 2 x 4-barrel tandem Single 4-barrel | 2 x 4-barrel short cross ram |
| Carburetor | Two 4-barrels Single 4-barrel | Two 4-barrels |
| Horsepower | 340-380 HP | 410-420 HP |
| Torque | 450-470 Ft. Lbs. | 460-470 Ft. Lbs. |
| Oil capacity | 4 qt. oil pan Plus 1 qt. for oil filter | 5 qt. oil pan Plus 1 qt. for oil filter |
| Crankshaft | Forged steel | 413 Crank with hardened journals & shot peened fillets. |
| Connecting Rods | Dropped forged “I” Beam | 413 rods but specially selected for quality. |
| Pulleys | Standard size and grooves | Smaller crankshaft pulley and deeper grooves on all pulleys. |
| Exhaust manifolds | Standard manifolds | Higher air flow and larger outlets. |
Production Years
The 413 Max Wedge was only produced for one year, 1962. The 413 engine was produced for seven years, 1959-1965.
413 and 413 Max Wedge Engine and Components: Differences
As stated earlier, both engines used the same block design, although there are some differences.
Horsepower and Torque
The Max Wedge engine has more horsepower than any year of production for the 413. Some of the passenger 413 engines had the same or more torque due to its longer branch manifold.
The following are the horsepower and torque ratings for the Max Wedge and Wedge engines:
1962 413 Max Wedge:
- 410 HP @ 5,200 rpm (11.0:1 C.R.)
- 460 Ft. Lbs. @ 4,400 rpm (11.0:1 C.R.)
- 420 HP @ 5,200 rpm (13.5:1 C.R.)
- 470 Ft. Lbs. @ 4,400 rpm (13.5:1 C.R.)
1959 413 Wedge Engine (4-barrel):
- 350 HP @ 4,600 rpm
- 470 Ft. Lbs. @ 2,800 rpm
1959 413 Wedge Engine (Tandem 4- barrels)
- 380 HP @ 5,000 rpm
- 450 Ft. Lbs. @3,600 rpm
1960 413 Wedge Engine (2×4-barrel long cross ram):
- 375 HP @ 5,000 rpm
- 495 Ft. Lbs. @ 2,800 rpm
1963 413 Wedge Engine (4-barrel)
- 340 HP
- 470 Ft. Lbs.
1964 413 Wedge Engine ( 4-barrel)
- 360 HP @ 4,800 rpm
- 470 Ft. Lbs @ 3,200 rpm
Engine Block
The 413 Max Wedge block had a different casting number and was the same as a 413 truck block.
- 413 Max Wedge casting number: 1852029
- 413 casting number: 2120529
It was stronger than the standard 413 block used in passenger cars.
Some people claim the Max Wedge blocks are thicker and have more nickel content adding strength.
The 413 Max Wedge engine blocks have notches on the exhaust valve side of the cylinder bores. The standard 413 blocks do not have them. This is to provide clearance for the Max Wedge’s larger exhaust valves.
Engine ID Pad
The Max Wedge blocks have different punch fonts than the standard 413 block. Typically, the font is larger. Also, the stamping for engine size and performance level are different than the passenger 413.
The Max Wedge engine ID pad stamps are the following:
- 11.0:1 engine: 413 HP
- 13.5:1 engine: 413 HC or 413 HP-HC
Following the engine stamp (underneath) will be the month, day and year.
A 413 engine block will have the following ID pad stamping:
- S-41
The letter S symbolizes the year, 1962. Following the engine stamp (underneath) will be the month and day.
Main Bearing Caps
Both engines use the same main bearing caps, but the Max Wedge caps are checked for hardness. Therefore, they may be stronger than the standard engine’s caps.
Cylinder Heads
The Max Wedge cylinder head design is based on the standard 413 heads but with the following differences:
- 25% larger ports than the standard engine.
- The heat cross over passage has been eliminated.
- The deck structure has been strengthened for more positive head gasket sealing.
They have different cylinder head casting numbers:
- 413 Max Wedge: 2402286
- 413 wedge: 2206924 or 2206324
Valves
Intake Valves
The intake valves are the same size (2.08″) but the underside of the Max Wedge intake valves are streamlined for better air flow.
Exhaust valves
The Max Wedge exhaust valves are 1/4″ larger in diameter. The following are the sizes of both engines:
- Max Wedge exhaust valve: 1.88″
- Standard 413 exhaust valve: 1.60″ or 1.74″ depending on year.
Valve Springs
The Max Wedge has dual valve springs, inner and outer, for a total of 32. The 413 has single springs with a total of 16 springs.
Valve Train
Rocker Arms
The Max Wedge rocker arms have adjustments due to the mechanical tappets. They are similar to the rocker arms used in the 413 300-H but include a locknut on the lash adjusting screw.
Other 413 engines with hydraulic tappets have different, non-adjusting rocker arms.
Pushrods
The Max Wedge engine’s pushrods are 0.040″ longer than the 413 wedge. This is to compensate for the difference in camshaft timing and smaller base circle diameter of the cam lobe.
Camshaft
The 413 Max Wedge has a more aggressive camshaft, higher lift and more duration. The 413 has a combination of hydraulic or mechanical cams while the Max Wedge cam only uses mechanical tappets.
Camshaft specs:
- 413 Max Wedge: .509″ lift/300° duration
- 413 Wedge: .389″ or .430″ lift/252°, 260°, 268° duration (depending on year and model car)
Pistons/Compression Ratio
Both engines were produced with aluminum pistons, but the Max Wedge had forged aluminum. The Max Wedge was produced with higher compression ratios. The standard wedge was produced with lower, different ratios depending on the year.
- 413 Max Wedge: 11.1:0 or 13.5:1
- 413 Wedge: 10.0:1 or 10.1:1
Intake Manifold/Carburetor
The Max Wedge came with one type of intake manifold while the 413 came with different types depending on the year and car model.
413 Max Wedge Intake Manifold:
- 2 x 4-barrel short cross ram
The 413 Wedge came with the following intake manifolds:
- Single 4-barrel
- 2 x 4-barrel tandem
- 2 x 4-barrel long cross ram
The Max Wedge only came with two 4-barrel carburetors while the Wedge came with either a single 4-barrel or two 4-barrel carburetors.
Oil Pan/Oil Capacity
The 413 Max Wedge oil pan has one more quart oil capacity than the 413. In addition, it has front and rear baffles and a swinging pickup pipe which the standard engine doesn’t have.
- 413 Max Wedge Oil Capacity: 5 quarts plus one quart for the filter.
- 413 Wedge oil capacity: 4 quarts plus one quart for the filter.
Crankshaft
The Max Wedge crankshaft is similar to the standard 413 except it has hardened journals and shot peened fillets.
The Max Wedge main bearing journals were ground 0.0005″ under the standard size to accommodate the F-77 Tri-Metal heavy duty bearings.
This grounding also provides additional clearances and a greater rate of oil flow between the bearings and journals.
The Max Wedge connecting rod journals were ground 0.001″ under the standard size for the same reasons.
Connecting Rods
Both engines had the same rods, dropped forged “I” beam construction but the Max Wedge rods were specially selected for the best quality.
Fuel Pump
The Max Wedge engine uses the same fuel pump as the standard engine but it has a higher pressure spring to deliver 6-8 p.s.i. at 1,500 rpm.
Exhaust Manifolds
The 1962 413 Max Wedge engine had brand-new exhaust manifolds never used in prior engines or 413s.
The cast iron tubular manifold has streamlined, upsweeping curves with a higher capacity over the standard manifold. The long branches have a 3″ outlet.
Accessory and Drive Pulleys
The Max Wedge has a smaller diameter crankshaft pulley to limit belt speeds. All the pulleys have a deeper groove to secure the belt and an air conditioning water pump is used.
If you have any questions about the difference between a 413 and 413 Max Wedge, send us an email found specifically on our contact page.
About 38 years ago I assembled my first Mopar engine. It’s at that time my hands on experience with Mopar engines, including the Max Wedge, started. Although my research of the engines started years earlier.
Read More 413 Max Wedge Articles
Cars Produced With a 413 Max Wedge Engine
Article Resources
- Google Books: Chrysler Engines 1922-1998
- 1962 Plymouth Super Stock 413 Owner’s Manual
- 1962 Dodge Ramcharger 413 Booklet
- Dodge Salesmen’s 413 Fact Booklet
- Plymouth Service Bulletin No. 62-78: 413 Cubic Inch Super Stock Engine (Maximum Performance)
