Chassis-dyno session

Had my '73 Dart on the chassis-dyno again recently to find out what the engine-swap from a 318 to 360ci netted me.

Nothing earthshattering, mindblowing or socks being knocked off miles away, just reporting the findings.

In short, it was about 64 rwhp more than the previous 318 engine in the same car and setup.

The 360 made 234 RWhp @ 4700rpm and about 295 ft/lbs @ 3550rpm.

Just like the 318, the 360ci engine also runs on LPG/Propane fuel and has an A518 and an 8-3/4" rear axle behind it.

The Propane system fuelline and lockoff-valves started to act as a restriction because the AFRs started going leaner above 3800 rpm.

Some more info posted on my website:
https://www.bigblockmopar.nl/2018/09/dodge-dart-dynoday-4/


Here is a combined videoclip of all the runs with dyno-charts to go along.
(Sound is always way better with headphones or a good remote PC-speakerset);
https://www.youtube.com/watch?v=Ut3cHopC4Ko

The Dyno is a Land-and-Sea dyno with Eddy-current dyno-hubs, which bolt directly to the rear axle.

Very interesting! Since the propane system is restrictive, is there any way to improve it ? Thanks for posting, nice looking car!

Thanks.

Fixing the fuel issue is about the same deal as with gasoline engines;
Upgrade the fuel lines and in this case also the lock-off valves (there's one in the tank and one in the engine bay.

Although I'm not really quite sure yet the fuelline is the actual limiter.
As propane evaporates from liquid to vapour, it expands some 270 times in volume.

The safety lock-off valves however have a smaller diameter inside and are more likely to limit flow to the propane vaporizer.

The carb used is an IMPCO 425, rated to flow 460cfm, which should be more than enough for this engine and cam-setup for now.