Originally Posted by turbodave
Cheers guys,
I'm left a little curious however; there must be quite a difference in the heads / cams or injection system if (on the same boost level) there is over a 20hp difference between the 2wd and 4wd?
Only minor improvments to the 4x4 head including cooling passages and combustion chamber size to improve emissions. Cams have the same profile. Power difference is down to the bigger intercooler, larger compressor trim and a touch more boost.
I assume the 0.48A/R isn't on the Sierras as standard then? If this is the only change, i assume the trim on the compressor is good, but the power was 'held back' with the restrictive exhaust turbine? As nitrous isn't out of the question for an easy, cheap power boost in the future for the strip, a larger exhaust housing would probably be a good point to start from...
.48 A/R is standard on all Cossies apart from the RS500 and Escorts. This exhaust housing is good for over 300bhp (more if a cut back wheel is used).
To clarify further - will both sierra ECU's swap with both looms? Is any ECU particually better, or cheaper to modify / get more power from than another?
Both ECUs?? There are L1, L6, L8, P8 and EEC IV. Worst (relativley) is the L1. Best is P8(but get your wallet out). Don't get hung up on what ECU as all can be sorted to have a properly running engine.
And are both / neither looms integral with the main sierra wiring loom - ie will the loom come with a load of redundant wires, or will it be just the Engine loom?
I believe all the Weber Marelli looms are separate but not 100% sure on the later cars.