J20A vs J20B

[Warwagon]

Thanks. I'm good with mechanical and engineering projects, I'm actually a collision repair tech.

[anibalrx8]

I still have my 2007 SX4 with out any break down and 120,000 miles on it as my daily driver so that I don't put that much mile and my fun car genesis coupe 3.8 2013. I love driving the sx4 as a DD. As for the j20b with cvt, I would not touch it, I don't like cvt and from what I have research, the only benefit is fuel economic, which has been prove to be the opposite or neutral, in general with all car manufactures, just my opinion.

I also wish Suzuki would still be here or came back!

[/I]

Having owned a 2007 with J20A/5 speed manual (143 hp) AND a 2012 with J20B/6 speed manual (151 hp), I can say I like the J20B the best. It has a much wider power band, due to the variable valve timing, and better fuel mileage. I have 165,000 miles on the J20B (mostly highway miles). It has been very trouble-free to this point. It has been the best car for the money I have ever owned. I wish Suzuki was still in the North American market so I could buy a new Suzuki.

[Samus]

Having opened both engine, top and bottom... I can tell the j20b has bigger rods and the bearings (all of them) seem like much better quality. The timing chain is also larger and looks more sturdy on j20b. There is no timing chain plate/shield at the top like the j20a which causes that annoying rattling sound when the chain becomes loose. Pistons are different, j20a has no pockets like the j20b. J20a has a cast iron engine base versus all aluminium for the j20b. Crankshaft and flywheel seems to be the same.

The head is where the j20b shines... Variable cam on the intake side. Better flow (ports seem a little larger on the intake side).

[Warwagon]

Definitely welcome improvements over the J20A save for the bad oil filter placement.
Crankshaft/flywheel are not the same but they share the stroke length though. J20B tone wheel is on the pulley side.

[alexsmith12]

I think the SX4 got the J20B in 2010, at least in the US, not sure about Australia.
Henno - transverse engines are set up quite differently to longitudinal mount - even when they are interchangeable - oil pump pickups, oil pans, intake & exhaust manifolds, sometimes the engine mounts. In most (but not all) cases you can swap the accessories over and drop the engine in - don't try this with Mitsubishi engines though.