[ngvddis]

Hello, i have an J18a engine and an J20a with plastic intake manifold from new grand vitara and I want to know witch combination is better to build J24 engine.
I will use hydraulic tappet lifters from J18a for sure, J20a crankshaft and rods.
Better keep the J18a engine block or J20a? Have the same height???

I want an J24a engine with 12+ :1 compression ratio.


Thank you

 

[fordem]

I seriously doubt that you can bore a J18a or J20a block out to 2.4 litres - you're going from 84mm bore to 92mm - I don't think there's enough meat in between the bores.

To answer your question, it doesn't matter which block you use, they are dimensionally identical & interchangeable - you might want to go look for one of the older J20A engines (pre 2005), I believe the rods are stronger, the post 2005 J20A uses a different rod with TTY cap bolts and there are reports of rod bearing failures on those newer motors that weren't common on the older ones. You'll also find that the older J20A motors have hydraulic lifters.

 

[ngvddis]

Thanks for your response.
I saw somewhere in the forum that J18A's have the smallest combustion chambers, then follows the J20A and lastly the J23A is that true or are the same engine heads?

 

[fordem]

The answer may depend on what vehicle the engine was fitted to - J18 head part numbers as used on the Sidekick Sport & Baleno/Esteem are different, but, one of the two matches the part number used on one of the J20s used in the early 2000's, so I could say the J18 & J20 use the same head, and be both correct & incorrect at the same time. As far as I know the J23 has larger chambers than the J18/J20.