Syclone turbo setup complete
#12
The engine is running at wastegate pressure, around 8psi. The fuel spider was replaced. The fuel pump has been upgraded to a Walbro 255 with new wiring; this raised the base fuel pressure by about 10psi to assist during open loop fueling. During normal operation the o2 feedback and fuel trims maintain driveability.
#17
http://www.youtube.com/watch?v=OBEd-TNz2Wg
just some part throttle boosting while merging on the highway--nothing exciting or impressive at this point. there's also a couple shots of logging the ignition advance
just some part throttle boosting while merging on the highway--nothing exciting or impressive at this point. there's also a couple shots of logging the ignition advance
#18
Also, FYI:
I don't have any tuning software for this engine. I suspect there may be none available, because it is such a low production model (OBD II 95 model). These 95 OBD II engines are speed density (MAP sensor only) but can only read up to about 105kPA, or basically atmospheric pressure. So the timing won't continue to retard as manifold pressure increases--it can't see boost. But the Syclone can:
The only Blazer timing map I have access to is this from a 2002 model:
The grams/sec calculation is based on measured airflow and rpm. You can see that timing flattens after about .60 grams/sec--that the equivalent of running this 95 Blazer at 105kPA. So even if I had a MAF car this timing issue would still be there once boost climbs high enough.
Now that I have two benchmark values, I'll say that the timing I've been observing hasn't been particularly aggressive. There appears to be less advance at the 100kPA MAP reading than the Syclone has at this pressure. This is probably because the Blazer is designed for 87 octane. I'd say it's equal or less advance than the 2002 Blazer is doing at higher load levels, and less timing than the Syclone at an equivalent 100kPA.
I'm not worried about the timing being a problem yet as far as reliability goes. The vehicle has gone wide-open-throttle but no wideband has been installed yet, so technically that might have been a little risky. Next mod is going to be a wideband to verify the AFR is ok. The 2002 power enrichment maps show a commanded AFR of 12.2:1 :
We'll see what that ends up being at 8psi with this increased fuel pressure. 12:1 would probably be ok these boost levels, maybe a little richer for an extra cushion. Most completely stock calibrations (on factory turbo cars) will command an AFR between 10.2: - 11:1 . I don't think the Syclone has a commanded AFR table, just a bunch of VE terms that are combined together to determine fueling.
I don't have any tuning software for this engine. I suspect there may be none available, because it is such a low production model (OBD II 95 model). These 95 OBD II engines are speed density (MAP sensor only) but can only read up to about 105kPA, or basically atmospheric pressure. So the timing won't continue to retard as manifold pressure increases--it can't see boost. But the Syclone can:
The only Blazer timing map I have access to is this from a 2002 model:
The grams/sec calculation is based on measured airflow and rpm. You can see that timing flattens after about .60 grams/sec--that the equivalent of running this 95 Blazer at 105kPA. So even if I had a MAF car this timing issue would still be there once boost climbs high enough.
Now that I have two benchmark values, I'll say that the timing I've been observing hasn't been particularly aggressive. There appears to be less advance at the 100kPA MAP reading than the Syclone has at this pressure. This is probably because the Blazer is designed for 87 octane. I'd say it's equal or less advance than the 2002 Blazer is doing at higher load levels, and less timing than the Syclone at an equivalent 100kPA.
I'm not worried about the timing being a problem yet as far as reliability goes. The vehicle has gone wide-open-throttle but no wideband has been installed yet, so technically that might have been a little risky. Next mod is going to be a wideband to verify the AFR is ok. The 2002 power enrichment maps show a commanded AFR of 12.2:1 :
We'll see what that ends up being at 8psi with this increased fuel pressure. 12:1 would probably be ok these boost levels, maybe a little richer for an extra cushion. Most completely stock calibrations (on factory turbo cars) will command an AFR between 10.2: - 11:1 . I don't think the Syclone has a commanded AFR table, just a bunch of VE terms that are combined together to determine fueling.
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03-20-2012 09:58 PM