We managed to achieve all this, which was nice. For some reason we couldn't get a reliable lambda value, it kept waving around between 0.8 and 1.0 throughout the rev/load range and at idle it was as high as 2.0 but again varied a lot so we didn't trust it, at idle this variation was probably because of the cam. CORRECTION on this - the cam plays a part but its also because the exhausts are such large diameter using a gas analyser probe shoved up the end of the exhaust the air in the room can get in at low rpm's and muck with the oxygen reading. I have a plan afoot to fit wideband O2 sensors in the collectors, connected to a suitable gauage/datalogger. I'm in the early stages of research at the moment but the Innovate LC1 and AEM 30-4900 systems look pretty good.
We did get stable CO for the 70mph load (to test throttle range) and full throttle power run and it was hovering around 2.5-3.0% which is tad on the rich side at around 13:1 A/F ratio which in my limited understanding is acceptable for these engines.
For the power run we had difficulty stopping the wheels spinning on the rollers, we had to spray WD40 on the tyres to soften them up and strapped the car down to get some load on the tyres. Here is Naomi being used as ballast:
Eventually we got a good power run in and this was the satisfying result:
376bhp and 392ft.lbs torque aren't bad, considering the engine spec I bought was 375/375! That would also explain why my neck hurts after a few good 2nd and 3rd gear blasts! Very satisfying to see the engine is making what it should but there is still the little niggle at light throttle it doesnt run as well as other people with similar engines/hot cams say their engines run (unless they're telling porky pies of course). Another visit might be on the cards at some point but now the focus moves towards prep for painting next week.
The cobra made a new friend at the garage where the rolling road is, a very nice looking GT40 (kit)
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