Another bolt on engine option.....

[mightymouse]

Turns out that some Mazda MX5/Miata's run an Aisin Warner A44DE gearbox.
However the MX5 autos seem to be as rare as.... so its technically easy but some may find it a challenge to source.
The U.S. was the major market for MX5/Miata autos apparently

This means that the "correct" MX5 auto bell housing will go onto an A44DE ( that a Vit AW4 auto ) thus opening up an interesting range of engine options. This is NOT speculation

Any of the Mazda B series 4 Cylinders will then bolt on, ranging from the boring SOHC 8 Valve 1.1 ltr - which is getting very old now, to the interesting 1.8 ltr BPD, producing 154 kW and 250 Nm. The later 2.0ltr and 2.4ltr variants are not compatible - but aren't as powerful anyway ( no turbo... ).

Contrast this with the lousy 109kw out of the troublesome Suzuki 2.5 ltr V6 and you will see the point.

As an aide the old 2.5 ltr Suzuki V6 started out as a joint Mazda / Suzuki venture. Being designed for N/S and E/W installations each manufacturer designed their own cam drives - enough said. Mazda kept developing the motor to its final form - 169kW where as Suzuki just kept it and its problems essentially unchanged. Even though they share a common heritage NONE of the parts now interchange and its unsuitable for a N/S installation for a number of technical reasons.

The most obtainable is the BPT. producing 134 kW and 237 Nm of torque.
These have a great reputation as being extremely strong and long lived.

Would be interested to see how 154kW and 250Nm would push a Vitara or suchlike.

[billbarbas]

Very interesting to know who would be stupid enough to do such a conversion!!!!

[cj!]

The later 2001-2005 H25A 2.5 V6 had 116kW and 213NM which is a little better. The H27A 2.7 V6 from the Xl-7 delivered 135kW @ 6000rpm and 250Nm @ 3300rpm which is getting better and they have been put in Vits with good results. I don't disagree though that they are nothing special as far as engines go and you'd be looking at over $2000 for the engine.

There is good support for the Mazda which is a plus

[gwagensteve]

I'd agree the BP turbo would be a very good starting point.

These motors don't seem to have any obvious problems AFAIK.

Steve.

[mightymouse]

The Mazda 2.5 ltr V6 is a VERY interesting engine, crank girdle, gear driven cams etc etc. Did lots of measurements to see if the Mazda goodies could be adapted to a Suzuki block - but its a definate no go. Also isnt technically feasible to be fitted in its own right even if you did the bell housing adapter bit as for a start there is no provision for a starter on the engine..... solutions are of course possible but it would be a very complex bell housing and the starter would end up facing the firewall which would create other issues.

I was just comparing 2.5ltr Mazda with 2.5ltr Suzuki...... and that was just a power comparison not design. With latter Mazda V6's the comparrison is even less atractive - although the Miller Cycle engines don't appal to me personally they are even more powerfull. If they just used the supercharger for boost the numbers would be spectacular.

The current Suzuki V6 is in fact a GM product and actually isn't a bad engine as such and with the right selection of parts could be made to work reasonably well - ie direct injection heads etc etc. Unfortunately the Suzuki versions intake manifod leaves a LOT to be desired, due to space restrictions the normally front facing throttle body has had to be turned through almost 180 degrees which has done exactly what you would expect as far as airflow is concerned. The computer models of the flow aren't very flattering - but the stock manifold for the Commodore isn't very flash either so....

As for stupidity - no one I know would put a BPT let alone a BPD in a Vit... just as well I don't own one isn't it ?

[mightymouse]

I'd agree the BP turbo would be a very good starting point.

These motors don't seem to have any obvious problems AFAIK.

Steve.

Chucking the air/air intercooler and replacing with air /water certainly would help the low speed characteristics as well... the Mazda install is obviously desiged for performance at speed ( the BPD was a rally special ) not cooling at low speed.

cj!'s install will probably show this low end improvement and the reduction in intake tract volume is a plus IF its plumbed well.

Having a PWR air/water cooler already makes this approach the obvious choice - especially as space is always in demand.

And how have the electric pumps actually worked out ? I've discussed it several times with colleagues.
A good control system would help lots IMO.

[gwagensteve]

I think the pumps are great. I still don't have enough thermo fan but that's not the pumps fault. I haven't done any work in improving the flow to assist with cold start ( flow through the throttle body) and heater function, there' a yellow 1.0 trayback interfering with progress on that front.

Despite the water/air, Cj will have a larger than stock intake volume because all the rest of the piping is the same (cooler sits in the same spot as the stock 660 one) but has a much larger internal volume, larger core and tanks, but I agree that the BPD motors intercooling could be improved from an off road point of view.

wierd question - are you sure mazda vans don't use a B series motor/AW-4 variant? Might make the bellhousing easier to find...

Steve.

[mightymouse]

Sure - no.... just didn't find any other SUITABLE listings of an EXACT match in any of my searches.
KIA use - but its way too heavy an engine etc etc.

Would open the market up if it were true so others might find it worthwhile.

There are so many variants of the Aisin Warner transmissions ( 3 speed, 4 speed lockup, no lockup, different input shafts, output shafts, extension housings, different ratio's etc etc ) that its VERY difficult to predict exactly what could go with what, even the experts get vague.

They must have a master index or something as he could tell me there were X variants with Y belhousings and Z output shafts, but when I started discussing interchangibility progress stopped.

So its a case of I know an MX5/Maita bell housing works - I've bolted them together.
I know the MX5 bell housing fits the BPD, Ive also bolted them together.

The converter is a bit more of an issue, the BPD was only available in manual but I have an MX5 converter thats not a precise match but that's better than can't do. Converters are also pretty well understood and aren't anywhere near as difficult to resolve.

About all i could get from the Auto Trans experts was vague answers and rediculous $$$, why would he bother with a "toy" Suzuki trans when he could make $5000 building auto's for patrols ? What can you say to that ? And if parts did need to be swapped he'd only do it as part of a total rebuild, even though the box is less than a year old.

[gwagensteve]

Fair enough - it wasn't clear from your original post that you already have access to an MX-5 auto and motor, only that some might find it hard to find.

Cool

Steve.

[mightymouse]

The Miata/MX5 version of the A44DE auto ( thats whats called an AW4 in a Vit ) - as you can see it has an extension housing and is hung from the top rater than supported from the bottom. Will check ratios to see what its fitted with when I can track the info down

Bellhousing/converter has...... "gone to a better place"..