Here's some more info I have found out regarding a potential performance rebuild from Eurospec. As I am not an expert on engine components, I had a good friend who is an expert call and talk to them about what they were proposing. Below are his thoughts.
I can't imagine anyone really tunes a ECU from these engines?
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Subject: Re: 1993 Eurovan 2.5 inline-5 engine
Bill,
I chatted with
Steve@overlandparts.com (he works at eurospecsport and is the one that was chatting with you via e-mail.
Pros:
- It sounds like they know what they are doing in regards to engine rebuilds with forged pistons.
- The motor will have 15-20% more torque than the stock 2.5L, which you already knew
- your AWD conversion sparked quite a bit of interest with Steve, so they may want you to bring the van to them for the motor work. They'll have more details as you near a decision on motors.
Con:
-The fuel system would need to be richened up a bit with the larger air volume moving through the motor, which is the same for our Subaru customers that go from a 2.0 to 2.2L. The issue here is Eurospec did not have a suggestion for a tuner. A built stroker motor (bigger displacement) without a tuner tends to be worse off than a stock displacement sized motor. Food for thought for when you continue further down this road.
Side note:
Steve briefly mentioned bumping the compressoin ratio by 0.5 or so. This increases the pressure inside the combustion area (top of piston to valves), thus allowing for a more dramatic explosion which creates more TQ. There is a tipping point though, and I do not know what it is with this motor and our climate. If the CR (compression ratio) is high with a low fuel grade (91) then engine knock may come into play. I see this when tuning built / stroked Subaru motors. When the CR goes up, the folks with 91 oct tend to require a bit of de-tuning in the ECU when compared to folks with 93 oct. This issue would be exaggerated with our higher elevation (5K vs eurospec at 300) and with higher loads (filled to the gills with gear). The best way to correct engine knock from the increased CR is through tuning. Unfortunately, Steve did not have a suggested tuner to use.
Tuner (someone with a means to connect with a computer to the car, that can then change the ECU versus trying to make changes to the motor itself):
It would be best to find a well experienced tuner, specific to Van motors and computers, before purchasing anything. As it stands, the 2.7L motor will have a lean issue and could use some ECU work in the Ignition table too.
Closing:
I would not hesitate to use this company to build a motor. Just do more research before pulling the trigger so you don't end up with a headache-mobile like the diesel one you had before.
Stephen Clark
IA Performance