engine tags

[Aaron Sanders]

In doing a search for a replacement 2.5 for my cougar I came across a few different 2.5 options does anyone know the difference in these?

2.5L (VIN L, 8th digit, DOHC), eng tag 8G-400 & 8G-401 series
2.5L (VIN L, 8th digit, DOHC), eng tag 9G-400 & 9G-401 series
2.5L (VIN L, 8th digit, DOHC), eng tag 9G-828 & 9G-829 series

[StuartGrant]

I imagine that those represent the return engine, the pre 2001 returnless engine, and the 2001+ returnless engine.

Functionally these engines are all the same, some parts are different from each, but they'll all go in the same car.

You can also use the engine from the 2000-2001 Mazda MPV, just swap over you manifolds and timing cover. Engine code AJ for those years only, later AJ engines were 3.0L.

[Blackcoog]

The MPV motor isn't anywhere near a stock replacement. All the vacuum lines need to be rerouted/modified, stock throttle body bracket doesn't work, EGR doesn't bolt up, wiring should be extended in some places, injector harness needs to be modified to sit flat between the 3L intake, you need a tune $$$, heads need to be modified for the alternator (99-00), crank bushing should be removed for MTX, ear on trans side should be removed if you want to use the SVT oil cooler, belt for the 01-02 Cougar would have to be used, etc. That is no where near a swap in motor. It's just slightly easier than some of the other 3L options. They would need to do some reading or have some time on their hands to figure out what needs to be done. We don't want some guy to pick one up and then come back and say WTF how do I get this to work.

[StuartGrant]

I was talking about the 00-01 split port 2.5L engine from the MPV, which is literally the same as our 2.5L with and without some parts, the build manual posted here actually has all the details on what's done differently. Both it and the 3L use the AJ engine code, which I expect makes things difficult from time to time.

He'd probably want to just straight out swap the intake and exhaust manifolds, the jackshaft plate is different I believe, the timing cover, but keep the DMD if it has it, and the alt bracket and stuff. Or, since he doesn't list what year his cougar is he might be able to forgo touching the timing cover at all.

Search eBay for the 2.5L AJ, you'll see what I mean.

Oh, and the AJ doesn't use a crank bushing.