I made the schlep over to Courtenay's again today for some more tweakery on my supercharger conversion having been stuck on an artificially low rev limit since the original conversion. After Vocky built me two low compression engines (I killed one at Silverstone), with uprated internals, I'd lost a fair chunk of power and was "only" running 243bhp.
When it was dyno'd a couple of months back as part of a post rebuild health check, I was running a custom Piper 2.5" system and the TMS manifold along with Saab Aero camshafts. Turned out the cams weren't a good match for the SC and/or engine as they didn't give any extra power and just increased the back pressure in the supercharger. This left me a little downhearted at the expense and the lack of power that I now had in comparison to the original higher compression conversion. In this spec, I was running 243bhp and 219 ft-lbs of torque and was finding the rev limit increasingly annoying.
I've recently fitted the 3.0" Tullett SC system and manifold and last week Vocky beat the well trodden path to my house to fit the Comp Cams blower cams that I managed to pick up from another member. Not knowing what kind of effect they might have had on the fuelling, I took it easy on the way to North Walsham. First order of business was to get the car on the dyno to see what was what. So, with the original map that I've been running, the Tullet system and the blower cams it immediately delivered 268bhp and 225 ft-lbs of torque.
Next job, get the rev limit raised to 7,000rpm (it was capped as my fuel pump was on it's way out when I had the original conversion) and give it another run. This time it was pumping out 285bhp and 235 ft-lbs of torque and looked like it was still climbing.
At this point, the standard tubby injectors were getting pretty close to their limits. So we decided to go ahead and fit Astra VXR injectors. As these were going on, it seemed rude not to fit the smaller 2.9" pulley to the supercharger. Turned out to be a four hour job to get the new one on and involved nearly everyone at Courtenays and an oxyacetylene torch to finally get it back on. So, another map gets squirted on to the ECU and we run it up on the dyno. Now we're cooking on gas. 298bhp and 250 ft-lbs of torque. Was quite a warm day, so on another day that's probably the 300bhp broken. May have been possible to extract a little more as the fuelling is slightly rich but would rather have that bit of safety.
Here's the chart showing the original run from a couple of months back, plus this mornings first and this afternoons final runs. Forgot to get the one in the middle for the 285bhp run. :roll:
Thanks to Vocky for his unending patience and his continual tinkering. Thanks to all at Courtenay's who continue to look after me and the car. And thanks to all of those of you, who've convinced me to keep the faith over the last 6 months. chinky chinky
When it was dyno'd a couple of months back as part of a post rebuild health check, I was running a custom Piper 2.5" system and the TMS manifold along with Saab Aero camshafts. Turned out the cams weren't a good match for the SC and/or engine as they didn't give any extra power and just increased the back pressure in the supercharger. This left me a little downhearted at the expense and the lack of power that I now had in comparison to the original higher compression conversion. In this spec, I was running 243bhp and 219 ft-lbs of torque and was finding the rev limit increasingly annoying.
I've recently fitted the 3.0" Tullett SC system and manifold and last week Vocky beat the well trodden path to my house to fit the Comp Cams blower cams that I managed to pick up from another member. Not knowing what kind of effect they might have had on the fuelling, I took it easy on the way to North Walsham. First order of business was to get the car on the dyno to see what was what. So, with the original map that I've been running, the Tullet system and the blower cams it immediately delivered 268bhp and 225 ft-lbs of torque.
Next job, get the rev limit raised to 7,000rpm (it was capped as my fuel pump was on it's way out when I had the original conversion) and give it another run. This time it was pumping out 285bhp and 235 ft-lbs of torque and looked like it was still climbing.
At this point, the standard tubby injectors were getting pretty close to their limits. So we decided to go ahead and fit Astra VXR injectors. As these were going on, it seemed rude not to fit the smaller 2.9" pulley to the supercharger. Turned out to be a four hour job to get the new one on and involved nearly everyone at Courtenays and an oxyacetylene torch to finally get it back on. So, another map gets squirted on to the ECU and we run it up on the dyno. Now we're cooking on gas. 298bhp and 250 ft-lbs of torque. Was quite a warm day, so on another day that's probably the 300bhp broken. May have been possible to extract a little more as the fuelling is slightly rich but would rather have that bit of safety.
Here's the chart showing the original run from a couple of months back, plus this mornings first and this afternoons final runs. Forgot to get the one in the middle for the 285bhp run. :roll:
Thanks to Vocky for his unending patience and his continual tinkering. Thanks to all at Courtenay's who continue to look after me and the car. And thanks to all of those of you, who've convinced me to keep the faith over the last 6 months. chinky chinky
