SSExi lives
#1
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SSExi lives
Well, look at this. SSExi is out of the shop under her own power.
Ya, she needs a bath, real bad.
I plan to do that as soon as I get back from picking up my son.
Took her for a little ride. Dang, I'm happy.
Right now the timing is a bit low, around 25* when driving, and about 16* under a heavier load. I've got a bit more testing to do, and need to replace the oil pressure sender I broke. Once that is done I can start the tuning. My LTFTs seem to be real good, but I want to get them closer to zero. As I said, timing is low, I hope to add a few degrees to that. But all in all, she pulls real good. Only got on it up to 70% throttle, and she whined a bit.
Now, I'm sure your asking, what did I do to fix the problem. Well, let me say that right now I hope I fixed the problem. I had no KR on this drive. Before I couldn't even get out of the driveway and I was seeing up to 15* After all the changes I was convinced it was not real KR, so I went in to the tune and opened the Knock Retard Attack Rate vs RPM table and turned down the settings in the 0 to 2400 RPM range. I didn't turn it off, just turned it way down.
Ya, she needs a bath, real bad.
I plan to do that as soon as I get back from picking up my son.
Took her for a little ride. Dang, I'm happy.
Right now the timing is a bit low, around 25* when driving, and about 16* under a heavier load. I've got a bit more testing to do, and need to replace the oil pressure sender I broke. Once that is done I can start the tuning. My LTFTs seem to be real good, but I want to get them closer to zero. As I said, timing is low, I hope to add a few degrees to that. But all in all, she pulls real good. Only got on it up to 70% throttle, and she whined a bit.
Now, I'm sure your asking, what did I do to fix the problem. Well, let me say that right now I hope I fixed the problem. I had no KR on this drive. Before I couldn't even get out of the driveway and I was seeing up to 15* After all the changes I was convinced it was not real KR, so I went in to the tune and opened the Knock Retard Attack Rate vs RPM table and turned down the settings in the 0 to 2400 RPM range. I didn't turn it off, just turned it way down.
#6
Senior Member
True Car Nut
A lot of guys with LT1 engines substitute an LT4 knock module, particularly if they don't run stock exhaust system or valve train. It seems to do a better job of filtering out the false knock signals. This is not the sensor, it is a module that installs in the PCM. I have read a couple of articles about doing this on a Bonneville. I don't know if it would suit your application, but if you get a chance google "LT4 knock module" and read some of the write ups.
#7
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Sure hope so. She seems to be running good. haven't opened her up yet. Want to get a lot of other things done first. But I did give her 8 pounds of boost and no knock. Not bad with 9.5:1 compression.
Was looking over my old scans. I had cruise timing in the mid 30s to low 40s, right now I'm mid 20s. I don't think I'll get that high with this compression, but would like to see mid 30s. Now all I need is some free time to get this done.
Was looking over my old scans. I had cruise timing in the mid 30s to low 40s, right now I'm mid 20s. I don't think I'll get that high with this compression, but would like to see mid 30s. Now all I need is some free time to get this done.
#8
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A lot of guys with LT1 engines substitute an LT4 knock module, particularly if they don't run stock exhaust system or valve train. It seems to do a better job of filtering out the false knock signals. This is not the sensor, it is a module that installs in the PCM. I have read a couple of articles about doing this on a Bonneville. I don't know if it would suit your application, but if you get a chance google "LT4 knock module" and read some of the write ups.
That module is something that Bill and I have talked about several times. It'* also what we ended up looking at. He sent me a 99 PCM and wiring harness to try. But after I got started installing it I found many issues that I would need to deal with. The alternator has a different plug, the MAP sensors are different, his harness didn't have a TPS plug, the EVAP plugs are different, and the IAT plug was different. I finally decided it'* not worth all the effort and put my harness back. Then hard tuned that area out. For the most part, I did exactly what your talking about, I just did it with software.