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LA- Heads

Mopar - Stock  
Stock 273/318:
These are a small port 1.75"/1.50" valve head. Very poor flow characteristics for racing purposes. ~135 cfm intake flow. Can be had in both open and closed chamber versions. Many later versions included swirl port etc. IMO Any head with a small port like this is not a great candidate for racing use. TOO Many people get caught up in this 308/302 "magic Swirl port" head game. Fact is, they are OVERRATED. If you want to make HP don't waste your time with 318 heads I don't care if they are "swirl port" heads or not. JUNK unless you have forced induction.

Stock 340/360 "J" head.
(596/915/587 castings etc). 1.88/1.60 valves. Larger port design than 318/273 heads. All open chambers, USUALLY in the 70-72 cc range. Flow #'s are around ~185 cfm stock. Best upgrade, Have machine shop cut for 2.02" Intake valves and do a 3 angle Valve job with 70 degree bowl cut. This alone without touching the rest of the ports, should bring a "J" head into X head territory, and beyond. "Fast One" is our resident Factory Iron head expert, and he has gotten over 280 cfm out of a fully ported Iron head. IMO this is about as far as they will go. Other drawbacks include weight (iron), large open chambers, a poor flowing exhaust port, and lack of flow above .600" The exhaust port is probably the Iron head greatest weakness. You can make the intake port flow ungodly #'s if you want, but if you can't expel all the burnt Hydrocarbons, the guy in the other lane is goanna WIN. This is why guys resort to WELDING up the exhaust on factory iron heads for better exhaust flow. A LOT of work. For all out racing unless a factory iron head is required by rules, this is not the best way to go.

Stock "X" head:
See above. Out of Box, they'll go in the ~215 cfm range, which is about what a J head will do with a 2.02" Bowl cut.

"T/A" Head:
See above. These require offset T/A Intake rockers. No great advantage. Leave these for the restoration crowd.
Mopar -Aftermarket


Two versions, open chamber and closed chamber. Aluminum, very light weight. 2.02"/1.60" Stainless valves. As cast they will flow ~240/180 cfm. Potential exists for 285-290 cfm intake flow with a lot of port work. (Read $$$) They accept stock intake manifolds, stock style rocker gear, and Stock header bolt pattern. The low and midlift flow #'s of a fully ported Edelbrock will flow right with a W-2 until the big lifts, where the W-2 pulls away. .600" is where the W-2 Shines and the E head dies. It is all about the Bowl size/shape and short turn. Nothing the E head can do about it, it was not cast as a race head, therefore it does'nt have the greatest short turn in the world. Similar problem with the factory Iron heads, they die at .600" lift and nothing you can do about it. For the $ the E head is a great choice.

Indy Cylinder heads modified version of the Edelbrock head. Relocated pushrod holes. Requires offset Indy Rockers. Uses stock intake and headers. The initial enthusiasm has worn off, when guys started putting these on flow benches and found they were no better than fully ported regular E heads at a higher cost

Brodix B1-BA:
Cast Aluminum. 59*. Closed chambers. Uses stock intake, Stock rockers, stock headers. Fully ported will flow ~300/220 cfm. More $ than E heads or W-2. Not very popular most likely due to cost. Overall a good head that is better than an Edelbrock, but no greater than W-2.

Brodix B1-BA-MC:
Cast Aluminum. 59* Closed chambers. The MC stands for Moved centerline, and is designed for a bore larger than 4.10" Offset race rockers required.

Mopar Commando:
Cast Aluminum. 2 versions small port, and a large port. Come bare, with roughed in 2.02"/1.60" seats. Cast in rocker stands, uses stock rockers, stock intake, and stock headers. Very little actual use or flow/dyno testing. . More $ than E heads, on par with B1-BA's price wise. VERY underrated head .

INDY 360-1:
Rectangular Port, closed Chamber. Aluminum copy of Batten's old W-2, only with revised chambers and rectangle ports. Uses INDY Rockers, Stock exhaust, and a W-2 style intake. INDY Inflates the Flow #'s on these heads, and they come cast with a poor valve Job. Fairly expensive as well. Most sold in "kit" from. Actual Flow #'s from a set of Fully ported (by INDY) heads on a SF-600 showed 321 cfm @ .800"!!!! However, cfm @ .600" was only 299 and at .500" it was 269 Making it worse than a fully ported W-2 at the lower lifts.

INDY 360-2:
Cast Aluminum, Oval Port version of the 360-1. See above, plus the Oval port version is said to flow less than the rectangle port version.

Mopar W-2:
Cast Iron, many different Combustion Chamber versions, open, closed, 65cc, 55 cc etc etc. 48* versions, 59* versions. Cast in rocker stands (econo version) Race rocker stands (all but econo) Standard length valves, or Long race valves. All come with roughed in 2.02"/1.60" seats. Bare castings. Out of the box flow 268/175 cfm. Require a W-2 bolt pattern intake, W-2 Offset intake rocker arms, and a W-2 style header flange/adapeter plate. With full port work, flow in excess of 315/220 cfm. They have an excellent short turn out of the box, and will flow all the way to .700" with proper short turn blending. The Econo versions are economically priced in either $320 each (std length) or $350 each (long valves) Also a very $ friendly head IF you don't have good rockers/intake to begin with. If you are not planning on running over .600" lift cam, the E head will flow right with a W-2...... The W-2 exhaust port being slightly better IMO.

Mopar W-5:
Cast Aluminum, bare castings, no longer produced. 59cc closed heart shaped combustion chambers. Roughed in 2.02"/1.60" seats. Have BAD reputation for casting and valve seat problems. Some true, most misconceptions. Several different castings over the years. Out of the box with a 3 angle VJ will go: ~280/160(?) The exhaust is terrible as cast. Potential exists for 340/245 cfm with FULL port and large valves. The Secret to the W-5 is it's low and mid lift Flow #'s. BEST 59 degree head out there. Requires Race W-2/W-5 offset rocker setup, W-2/W-5 Intake, and W-5 headers.

Mopar W-7:
Cast Aluminum, bare castings no longer produced. Closed Chambers. MANY different versions avail over the years, some 59* heads some 48* heads. Requires a "Lazy W" Rocker arm setup. W-7 intake and W-7 headers. Few people run the W-5, even fewer run W-7's.....

Mopar W-8:
Now were are into exotic stuff. 48 Degree R-3 Race block required. W-8 Rockers (JESEL, T&D ect.), W-8 Intake, W-8 Valve coers, and W-8 headers required. Bring your check book. Most get CNC ported, and will flow in the 365 CFM range.

Mopar W-9:
Again 48* R-3 required, W-9 Intake, W-9 Rockers, W-9 headers. Do use standard valve cover unlike W-8. Again CNC porting will be in the 365+ cfm range. valve size on a head like a W-8 or W-9 will be in the 2.18" range and you will be running a BIG bore motor to deshroud the valves.

Mopar P-7:
Cast Aluminum. NASCAR Winston Cup head. Requires R-5 Race block. P-7 rockers, P-7 intake, P-7 headers, P-7 valve covers.

Mopar P-5:
Now we have reached the Pinnacle of all SB Chrysler heads. The one we all wish we had the $ to afford. Designed for NHRA Pro-Stock Truck applications. Cast Aluminum, Hemi Combustion Chambers. R-4 race block or Aluminum Block required. P-5 valve covers, P-5 rockers, P-5 headers, P-5 sheet metal intake all required.

Slant 6 Engine Cylinder Heads Casting Numbers

Casting Number Engine CID Year Intake Exhaust
2206035 170/225 1962-65 1.62 1.36
2843169 170/198/225 1966-74 1.62 1.36
3698995 198/225 1972 1.62 1.36
3614850 198/225 1972-73 1.62 1.36

LA Engine Cylinder Heads Casting Numbers

Casting Number Engine CID Year Intake Exhaust
2465315 273 1964-65 1.78 1.50
2532080 273 1964-65 1.78 1.50
2536178 273 1966 1.78 1.50
2658234 273 1966 1.78 1.50
2658920 273/318 1966-67 1.78 1.50
2843675 273/318 1968-74 1.78 1.50
2268341 318 1962-67 1.84 1.56
2658234 318 1967 1.78 1.50
2843675 318 1968-74 1.78 1.50
3769973 318 1975-83 1.78 1.50
4027163 318 1977-86 1.78 1.50
4027593 318 1977-84 1.78 1.50
4323302 318 Fast Burn 1985-86 1.78 1.50
4323345 318 Police 1983-86 1.78 1.50
2531894 340 1968-70 2.02 1.60
3418915 340TA 1970 2.02 1.60
3418915 340 1971-72 1.88 1.60
3671587 340 1973 1.88 1.60
3418915 360 1970-72 1.88 1.60
3671587 360 1973-74 1.88 1.60
3769974 360 1975-76 1.88 1.60
3671587 360 1976 1.88 1.60
4027569 360 1977-86 1.88 1.60