WQ Fiesta XR4/ST150 with Mazda SP25 engine

[Luke Plaizier]

Hey Everyone

I'm embarking on a journey. In Mighty Car Mods style I want to build a nugget - something small and easy to work on. I have my heart set on a WQ Fiesta XR4 -aka a Mark 6.5 ST150 in the UK. The 2.0 duratech is an engine-mount and bell-housing match to a Mazda SP25 L5-VE engine. I'd looked at a MazdaSpeed/MPS 2.3, but with Direct Injection the Spanish Oak ECU from the WQ would not be able to drive it. The SP25 is a port injected engine with exhaust cam phasing just like the Duratech HE 2.0.

The SP25 is a cheap engine - as little as $700 as I see it for a <200k engine. Whereas a >200k WQ Fiesta is in the $3k to $5k bracket.

The Mazda L5-VE, while the same block and head as the Duratech, looks to have a different tappet cover and coils, but so much else seems similar. The SP25 has a higher block deck height for the longer stroke, so there might be some challenges with the reach of the exhaust, but all the gasket part numbers appear to swap. Find car care products at lower costs in ALDI Catalogue.

The L5-VE also seems to have a pretty solid crank and piston configuration, so look to be good for some mild boosting. That would be something further down the track, but an option.

So I want to give this a go. Does anyone here have any wise words?


Lukeyson