Problem with knock
#1
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Problem with knock
Lets see if i can get some lights shed on my recent street tune i had done.
I recently had a street tune done on my evo 8. car has hks 264 cams, shearer fab tubular manifold, 38 mm wastegate, unknown size precision turbo ive been meaing ot check the size on the compressor housing. (made enough power to trap 122 in the 1/4 mile)nand precision 880cc injectors.
Now i got tuned maybe 6 months ago, after the tune i would get knock here and there so i would sometimes run octane booster every fill up and it would go away. well recently its gotten worse and worse. I eventually lowered my MBC to set the boost to 19 20ish lbs down from what my boost gauge was reading 25-26.
Now even with the lower boost pressure im still getting crazy knock counts. 8-12 knock counts on a given pull. Can somebody take a look at my tune and see if my timing values are out of whack or just to high? And give me some pointers on where to make adjustments. I get knock during spool up 4k and above. If you guys would need a datalog i also have one i could attach, figured yall would like to see the tune and see if anything is off.
Also have new plugs gapped at .21
Hopefully i attached it right
I recently had a street tune done on my evo 8. car has hks 264 cams, shearer fab tubular manifold, 38 mm wastegate, unknown size precision turbo ive been meaing ot check the size on the compressor housing. (made enough power to trap 122 in the 1/4 mile)nand precision 880cc injectors.
Now i got tuned maybe 6 months ago, after the tune i would get knock here and there so i would sometimes run octane booster every fill up and it would go away. well recently its gotten worse and worse. I eventually lowered my MBC to set the boost to 19 20ish lbs down from what my boost gauge was reading 25-26.
Now even with the lower boost pressure im still getting crazy knock counts. 8-12 knock counts on a given pull. Can somebody take a look at my tune and see if my timing values are out of whack or just to high? And give me some pointers on where to make adjustments. I get knock during spool up 4k and above. If you guys would need a datalog i also have one i could attach, figured yall would like to see the tune and see if anything is off.
Also have new plugs gapped at .21
Hopefully i attached it right
#2
No data log!
The timing table looks fine, but you could still lower timing to see if knock would go away.
Equally important is that you need to check your AFR, an aging fuel pump or a fuel issue would lead to leaner AFR & knock.
Otherwise, it could be false knock caused by some engine bay noises. At 8-12 counts you should be able to audibly hear it if you have a good ear or you could verify it through using det cans.
The timing table looks fine, but you could still lower timing to see if knock would go away.
Equally important is that you need to check your AFR, an aging fuel pump or a fuel issue would lead to leaner AFR & knock.
Otherwise, it could be false knock caused by some engine bay noises. At 8-12 counts you should be able to audibly hear it if you have a good ear or you could verify it through using det cans.
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I can get a log today. I really think its false knock because i cant hear it at all and i pulled 4 to 5 degrees out of the spool up area and it still knocked. Going to be double checking everything in the engine bay and exhaust related
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