G52b swap for 4G52 ?

[OffWhite50]

According to my service manual, It says the G52b and the 4G52 engines are both U model 2.0 engines, The only difference that I'm seeing is that the 4G52 is a non jet valve head.The G52b I have in my 1st gen needs to be rebuilt and I was thinking of replacing my engine with a 4G52 instead because i heard that its is a better performance motor.I still need to take my motor apart, but i feel like the Jet Valves are what caused my G52b engine to fail.

Does anyone know if my distributor, alternator, starter motor, and wiring harness from my G52b will work on a 4G52? Can anyone provide me with any info on the difficulty of swapping in a 4G52?

Are the benefits of the swap worth the trouble if my ideal end goal for the trucks engine is to have a John baker cam twin side drafts, and a Header?

[geezer101]

As far as I know everything is interchangeable. Is your G52B running points ignition or an ICM distributor? The wiring on these trucks is very basic and even if there is a difference (there shouldn't be) it will take little effort to adapt it. The 4G52 is a great little engine and responds well to minor mods. Get rid of the water pump driven radiator fan for an electric thermo (all gains here - more engine bay room, less load on the water pump bearings, degoverns the engine for improved throttle response, cools the engine when it actually needs it), port the head to match the intake manifold (you can tidy up the exhaust ports but don't alter the port sizes), delete the anti pollution garbage and retune the ignition timing and it will feel more responsive, idle smoother and improve top speed. Use a Weber carb and it will gain more mid to top end power. Add some good quality headers and it will gain torque.

[OffWhite50]

As far as I know everything is interchangeable. Is your G52B running points ignition or an ICM distributor?

Thanks for your input Geezer, I have the point-less type distributor with igniter

[geezer101]

O.k. so there wasn't a change-over point with the distributor. I used a 4G52 + A904 trans in a Chrysler Galant wagon (think 70's Dodge Colt) and it was fierce to drive. No mods to the engine except for an electric thermo fan and a 2" exhaust off the cast iron headers. A bit of experimenting with tuning it (it was running a breaker points distributor) and I was able to to get it to blip a flame or 2 when I came off the throttle hard - it roasted the chrome blue on the rear bumper in one spot and scared other motorists :grin:

[pennyman1]

4g52 is also known as a g52b in the USA - the 2.0 version of the g54b 2.6. Both are Astron series motors.

[OffWhite50]

I took my head off today and the jet vales caused a crack. The bottom end still looks good so does anyone know where i can source a 4g52 non jet valve head? It seems easier to find a 2.6 head but I've heard the 2.0 revs higher and has more compression. Is their any advantage to the 2.6 head over the 2.0?

[pennyman1]

the 2.6 head is a lower compression head on a 2.0 motor due to the larger combustion area in the head. A trick back in the day was to swap 2.0 heads on 2.6 motors to raise the compression. The 2.6 head can be shaved to regain the compression, but I doubt you would really notice the difference. The good news is you could run more advance without worrying about detonation. The non jet2.6 heads will work, but you need an 81 up intake manifold to use it as the non jet heads are the later style intake bolt pattern.