SlowWrangler

I am trying to find out if a 5.3 is really that much better than a vortec 350 for a vehicle that is more concerned with low to mid range torque and is also carbed. I have seen the comparison's of the 5.3 vs the 350, but those are comparisons are generally fuel injected. Fuel injected, the ls type engine should be better as the heads were designed around fuel injector angle (Chevy LS1/LS6 V-8s book by Handzel). However, I am leaning toward a carb (I have my own reasons). So in that light does the Gen III engine really have that much of an advantage? The heads for the Vortec 350 and the LS were both designed around the same era with the Vortec 350 having incredible intake velocity at .3 and .4 lift. Granted the LS has better ignition management with the DIS, but if I am not going to turn more than 5500RPM, is that an advantage? Both have roller cams but the LS does have roller rockers.

The reason I ask it that I am going to swap one of these into my Wrangler this summer. The 350 has the advantage of being able to find useable long tube headers and oilpans. The cost is much cheaper for the 350 (oil pan, headers, intake, accessories). However, if the 5.3 is THAT much better based on some technology I am overlooking, I am game.

One last item, if I do go with the 5.3 and run the MSD ignition controller for the carb conversion, is there a way to diagnose the sensors? How do you know if the camshaft sensor/crankshaft sensor/MAP sensor is going out or if the controller is having issues

I have just started learning the Chevy lingo as I have been a long time Ford guy with many Mustangs, Thunderbirds, and even Merkurs in my past. But for the Wrangler, the Chevy engine swap is by far the easiest.

Thanks!!!

Pop N Wood

iTrader: (1)

If you want to avoid the EFI vs carb debate you could post this in the carb forum on this site.

The MSD box lets you hook a lap top to it to monitor the sensor outputs. It only really uses a cam sensor, crank sensor and optional MAP sensor. MAP reads right on the laptop display. Lose the crank sensor and you lose the RPM signal on the lap top. The cam sensor is a little harder to diagnosis but funny thing the motor only needs the cam sensor to start up.

Just make sure you get the MSD box and not the Edlebrock box cause Eddy decided to delete the lap top port from their boxes.

As for vortec vs. LS in jeep I'll let someone with first hand experience answer. I do know that roller cam allow much more aggressive cam lobe profiles so the benefits can be felt throughout the whole RPM band.

88Fbody6L

iTrader: (5)

The gen one is cheaper to build by far. However, the gen 3 has some advantages: no distributor, 6 bolt mains, roller rockers, hardly any issues with oil leaks. The gen 3 is a more durable engine that has more potential for good power with stock heads and just a cam swap. Tough call, but if the budget allows I would go with the gen 3

SlowWrangler

I didn't think about the RPMs with the laptop. Great idea.

As far as issues with the 5.3, the headers are a pain. I don't know of any long tubes that work for a wrangler that are not WAY overpriced. The 5.3 truck exhaust manifolds do not work so I would be using f-body or corvette exhaust manifolds (may flow pretty good compared to cheap headers??). Also, the 5.3 truck oil pans sit way low so you either need a decent body lift or again use a f-body or corvette oil pan.

From my other thoughts, I was thinking that maybe the wet flow charachteristics of using a carb and carb intake manifold may be better optimized for the vortec 350 than the 5.3.