318 engine differences between CA and 49 state versions

[remytherat]

As a California resident it seems like we often get the dumbed down, castrated version of whatever the rest of the country gets in terms of performance. I understand this fully kicked in in the mid 70s, but were there differences in the 67-69 iteration of the LA? PCV configuration, heads, exhaust manifolds? My Chrysler catalog does not give the state by state variations of cars at any point in time so I'm wondering if I'm being cheated of any power

 

[GTX JOHN]

Generally just Carb and Ignition tuning
on the 318 as I recall in those years.

Some of the engines like the 67 440 HP had
a much smaller carb than the non Cal engine that
really killed performance (625 carb VS 750 approximately)

 

[67Dart273]

I've heard rumors that some in the later (smog) years used different cam timing, but not sure.

 

[Mattax]

Changes from year to year. Agree with ^^^ In the master Tech booklets and elsewhere Chrysler wrote that the cam timing was slightly changed to trap more heat.

Master Technician Service Conference - Chrysler's Training for Mechanics

The Imperial Mailing List Online Car Club is dedicated to the preservation, appreciation and restoration of Imperials and Chrysler Imperials of all years, models and body-styles.

www.web.imperialclub.info

See sessions from late '67 on engine and CAP and then '70 etc.

MY 1968 is the first production year for the LA 318. Shop Manuals show the differences in initial timing and distributor timing. None of it is really awful in terms of performance off idle. The big goals those early years was to reduce CO & HC at idle and under deceleration. Running the timing at idle a little late put more heat into the cylinder walls. This burns the mix more completely but hurts power. So comparing non-smog to smogged specs you'll notice idle rpms are slightly higher on smogged engines. So fuel consumption at stop lights and idling is slightly higher.

Below is graphed from the FSM specs and shows the most extreme differnces in timing from a CAP to a non CAP.
I don't know if any non-CAP 318 were sold in US cars that year.
Point is that timing was most different at idle, and pretty much the same above 1400 rpm.
With a manual transmission, the only power needed at idle is to overcome engine friction, turn the water pump, etc.

 

[Mattax]

The real killer in my opinion was the timing delay implemented around '73 IIRC. Certainly was on my '75 slant six. OSAC. Just awful in terms of acceleration, especially part throttle.
Early cats were pretty restrictive too. Don't know when Calf cars got them. Good high flow cats didn't really hit the scene until the Mustang 5.0

 

[krazykuda]

My 67 formula S 273 had California emissions which was a green vacuum pod that had three ports... One went to ported vacuum on the carb, the other to intake manifold vacuum, then the other port hooked up to the vacuum canister on the distributor...

 

[cudamark]

My 67 formula S 273 had California emissions which was a green vacuum pod that had three ports... One went to ported vacuum on the carb, the other to intake manifold vacuum, then the other port hooked up to the vacuum canister on the distributor...

Yup, that was the C.A.P. (Cleaner Air Package) that started in 1966. It changed how the vacuum advance worked and had different (read retarded) timing specs.

 

[67Dart273]

It got worse, too. Many of you know I was stationed at NAS Miramar, San Diego. This was 70 clear to my discharge in 74 (electronics tech, I was in for 6)

Part of that time I had a part time job at the auto hobby shop on base. SOMEtime in those years, CA mandated RETROFIT smog devices on some older cars. There were several kits, likely the "best" of which was made by Carter. But one of the worst (don't remember the brand, was a simple kit, instructions, two vacuum caps, and carb adjusting screw add on green caps, and some green silicone.

I saw one of these on a 55 Chev, NOW LET'S JUST think about this a minute.......

So say it's 74, this poor abused mostly worn out 55 Chev is nearly 20 years old. The cooling system/ radiator is all clogged up with San Diego water, some of the worst there is (for lime and other minerals) so the engine runs HOT already

The purpose of this kit is to REMOVE AND DISCARD the vacuum advance hose, PLUG them permanently, and they LEAN the carb way down and CAP off the screws so that they cannot be adjusted, then slather bright green silicone all over them for a "seal." And you RETARD the initial timing, so now it REALLY runs hot.

First time I saw one of those messes I just stood there in disbelief.

I'm sure this achieved the desired result---killing off older car engines, thus getting them off the road.

 

[cudamark]

The worst one was the STP kit, where you had to drill into the exhaust somewhere and thread in a valve. Talk about ruining some vintage parts.