Low power on SOS stage 2?
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Joined: May 2012
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First thing that doesn’t jive is your 13psi. This is too low for a 3.4" pulley on that blower. You should be netting 15psi minimum and up to17psi. So that can only mean really 3 things, starting with the most likely first. 1. Your SC belt is slipping and or a bad coupler allow boost to escape. 2. The boost gauge is misreading. 3. You have significant engine leak down/blow by problems.
Even at 13psi, a corrected 350whp is low on that blower, which would point to the dyno itself, the operator/tuner providing a lousy run or tune, or once again a nasty engine leak down/blow by.
Coil packs like spark plugs either fire or they don’t, and weak spark will show the same symptoms usually as not firing at all because the spark is too weak to ignite the fuel. These symptoms are easy to depict. They don’t come up as detonation, they come up as a misfire which to the trained ear is very different sounding. Your dyno graph would be smooth and then very choppy when you lose spark and your tuner should be able to depict this from detonation, no timing correction will make a difference in this regard. It could be that he thinks its detonation and is lowering your timing beyond nominal levels providing very low hp readings. What is your spark gap? You should be in the 0.25 range. Can go down to 0.20 to troubleshoot, but shouldn’t need to at your power/set up level.
Even at 13psi, a corrected 350whp is low on that blower, which would point to the dyno itself, the operator/tuner providing a lousy run or tune, or once again a nasty engine leak down/blow by.
Coil packs like spark plugs either fire or they don’t, and weak spark will show the same symptoms usually as not firing at all because the spark is too weak to ignite the fuel. These symptoms are easy to depict. They don’t come up as detonation, they come up as a misfire which to the trained ear is very different sounding. Your dyno graph would be smooth and then very choppy when you lose spark and your tuner should be able to depict this from detonation, no timing correction will make a difference in this regard. It could be that he thinks its detonation and is lowering your timing beyond nominal levels providing very low hp readings. What is your spark gap? You should be in the 0.25 range. Can go down to 0.20 to troubleshoot, but shouldn’t need to at your power/set up level.
The speak plugs are the BKR8EIX 2668 iridium and I think the gap was untouched on them from how they come, my tuner said that the gap was fine.
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Originally Posted by s2000Junky' timestamp='1413395644' post='23370534
First thing that doesn’t jive is your 13psi. This is too low for a 3.4" pulley on that blower. You should be netting 15psi minimum and up to17psi. So that can only mean really 3 things, starting with the most likely first. 1. Your SC belt is slipping and or a bad coupler allow boost to escape. 2. The boost gauge is misreading. 3. You have significant engine leak down/blow by problems.
Even at 13psi, a corrected 350whp is low on that blower, which would point to the dyno itself, the operator/tuner providing a lousy run or tune, or once again a nasty engine leak down/blow by.
Coil packs like spark plugs either fire or they don’t, and weak spark will show the same symptoms usually as not firing at all because the spark is too weak to ignite the fuel. These symptoms are easy to depict. They don’t come up as detonation, they come up as a misfire which to the trained ear is very different sounding. Your dyno graph would be smooth and then very choppy when you lose spark and your tuner should be able to depict this from detonation, no timing correction will make a difference in this regard. It could be that he thinks its detonation and is lowering your timing beyond nominal levels providing very low hp readings. What is your spark gap? You should be in the 0.25 range. Can go down to 0.20 to troubleshoot, but shouldn’t need to at your power/set up level.
Even at 13psi, a corrected 350whp is low on that blower, which would point to the dyno itself, the operator/tuner providing a lousy run or tune, or once again a nasty engine leak down/blow by.
Coil packs like spark plugs either fire or they don’t, and weak spark will show the same symptoms usually as not firing at all because the spark is too weak to ignite the fuel. These symptoms are easy to depict. They don’t come up as detonation, they come up as a misfire which to the trained ear is very different sounding. Your dyno graph would be smooth and then very choppy when you lose spark and your tuner should be able to depict this from detonation, no timing correction will make a difference in this regard. It could be that he thinks its detonation and is lowering your timing beyond nominal levels providing very low hp readings. What is your spark gap? You should be in the 0.25 range. Can go down to 0.20 to troubleshoot, but shouldn’t need to at your power/set up level.
Joined: Mar 2005
Posts: 22,143
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From: 949
my first try canme in at 342whp. after a leak down and compression test found the issues.
You could hear valve guides pissing air on #3 running 4.0" one tapped valve, Supertec Springs were chit. bought another set.
After valve job and 3.8" 382whp at just under 12 lbs
You could hear valve guides pissing air on #3 running 4.0" one tapped valve, Supertec Springs were chit. bought another set.
After valve job and 3.8" 382whp at just under 12 lbs
Thread Starter
Joined: May 2012
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Compression came out to be like 220 across the board
Thread Starter
Joined: May 2012
Posts: 191
Likes: 0
Originally Posted by leoxle' timestamp='1413396849' post='23370556
[quote name='s2000Junky' timestamp='1413395644' post='23370534']
First thing that doesn’t jive is your 13psi. This is too low for a 3.4" pulley on that blower. You should be netting 15psi minimum and up to17psi. So that can only mean really 3 things, starting with the most likely first. 1. Your SC belt is slipping and or a bad coupler allow boost to escape. 2. The boost gauge is misreading. 3. You have significant engine leak down/blow by problems.
Even at 13psi, a corrected 350whp is low on that blower, which would point to the dyno itself, the operator/tuner providing a lousy run or tune, or once again a nasty engine leak down/blow by.
Coil packs like spark plugs either fire or they don’t, and weak spark will show the same symptoms usually as not firing at all because the spark is too weak to ignite the fuel. These symptoms are easy to depict. They don’t come up as detonation, they come up as a misfire which to the trained ear is very different sounding. Your dyno graph would be smooth and then very choppy when you lose spark and your tuner should be able to depict this from detonation, no timing correction will make a difference in this regard. It could be that he thinks its detonation and is lowering your timing beyond nominal levels providing very low hp readings. What is your spark gap? You should be in the 0.25 range. Can go down to 0.20 to troubleshoot, but shouldn’t need to at your power/set up level.
First thing that doesn’t jive is your 13psi. This is too low for a 3.4" pulley on that blower. You should be netting 15psi minimum and up to17psi. So that can only mean really 3 things, starting with the most likely first. 1. Your SC belt is slipping and or a bad coupler allow boost to escape. 2. The boost gauge is misreading. 3. You have significant engine leak down/blow by problems.
Even at 13psi, a corrected 350whp is low on that blower, which would point to the dyno itself, the operator/tuner providing a lousy run or tune, or once again a nasty engine leak down/blow by.
Coil packs like spark plugs either fire or they don’t, and weak spark will show the same symptoms usually as not firing at all because the spark is too weak to ignite the fuel. These symptoms are easy to depict. They don’t come up as detonation, they come up as a misfire which to the trained ear is very different sounding. Your dyno graph would be smooth and then very choppy when you lose spark and your tuner should be able to depict this from detonation, no timing correction will make a difference in this regard. It could be that he thinks its detonation and is lowering your timing beyond nominal levels providing very low hp readings. What is your spark gap? You should be in the 0.25 range. Can go down to 0.20 to troubleshoot, but shouldn’t need to at your power/set up level.
[/quote]
Alright, I'll try that out and see what happens. Thanks!
Joined: Oct 2002
Posts: 8,044
Likes: 6
From: South Florida
Originally Posted by Picturepro' timestamp='1413398039' post='23370570
my first try canme in at 342whp. after a leak down and compression test found the issues.
You could hear valve guides pissing air on #3 running 4.0" one tapped valve, Supertec Springs were chit. bought another set.
After valve job and 3.8" 382whp at just under 12 lbs
You could hear valve guides pissing air on #3 running 4.0" one tapped valve, Supertec Springs were chit. bought another set.
After valve job and 3.8" 382whp at just under 12 lbs
Compression came out to be like 220 across the board
Thread Starter
Joined: May 2012
Posts: 191
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Originally Posted by leoxle' timestamp='1413401857' post='23370668
[quote name='Picturepro' timestamp='1413398039' post='23370570']
my first try canme in at 342whp. after a leak down and compression test found the issues.
You could hear valve guides pissing air on #3 running 4.0" one tapped valve, Supertec Springs were chit. bought another set.
After valve job and 3.8" 382whp at just under 12 lbs
my first try canme in at 342whp. after a leak down and compression test found the issues.
You could hear valve guides pissing air on #3 running 4.0" one tapped valve, Supertec Springs were chit. bought another set.
After valve job and 3.8" 382whp at just under 12 lbs
Compression came out to be like 220 across the board
[/quote]
It's not that low. Its supposed to be 245 if perfect, and my numbers are consistent. Some I think were actually 230, it was from 220-230. And yeah I did everything properly. Warmed up engine, all plugs out, fuel fuse out, WOT.
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Joined: Jan 2011
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220-230 are good numbers for compression. As long as they are consistent between all four cylinders.
I'm on a walbro 255 pump and stock fPR. And no my tuner didn't mention any of that, only said something about the knock sensor going crazy after he tried to pull more timing. Something like that. And yeah I saw the boost plot, it did show 13 but my aem wideband is showed 10, I mmight'v missed it though if it displayed 13.
The reason I ask about your fueling setup is because I personally had an issue where a 340 LPH pump was overrunning my stock FPR and causing my base fuel pressure at the rail to be 63+ PSI. My tuner didn't know this the first time I tried to get the car tune and he had a hell of a time because it seemed like he was running out of injector up top. So he just played it really conservative and thus I ended up with really low numbers on my first go. After I installed a fuel pressure gauge on the rail I realized I had an issue. Ordered an AEM FPR to dial back the base fuel pressure to the standard 43-45 PSI and all was well after that. Car acted right up top, plenty of injector duty cycle left, able to go more aggressive on the timing, and ended up with 393 WHP at 16 PSI on a Novi 1220 (which flows less than your Novi 1200).
Now, my issue was because I was using a 320 LPH pump with the stock regulator. Your 255 LPH pump might not have the same issue since it flows less and the stock FPR can likely keep up with that flow without the base pressure rising. Only way to be 100% sure is to get a fuel pressure gauge at the rail. Not saying that its necessary or that its what's causing the problem. Just something to think about.
Originally Posted by CoolGuy094' timestamp='1413387991' post='23370375
Seems low to me, especially AFTER a 15% correction bump. That would mean that your true number on a Dyno Dynamics before correction was sub-300 WHP. That just isn't right. I made nearly that on a Mustang Dyno with the stage 1 kit, Novi 1220.
What fuel pump do you have, and are you still using the stock FPR? Did the tuner mention anything about you running out of fuel or running out of injector duty cycle?
Did you see a plot of your boost pressure while you were there? The discrepancy between your boost gauge and his readings is odd; what boost gauge do you have?
What fuel pump do you have, and are you still using the stock FPR? Did the tuner mention anything about you running out of fuel or running out of injector duty cycle?
Did you see a plot of your boost pressure while you were there? The discrepancy between your boost gauge and his readings is odd; what boost gauge do you have?
Now, my issue was because I was using a 320 LPH pump with the stock regulator. Your 255 LPH pump might not have the same issue since it flows less and the stock FPR can likely keep up with that flow without the base pressure rising. Only way to be 100% sure is to get a fuel pressure gauge at the rail. Not saying that its necessary or that its what's causing the problem. Just something to think about.
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Joined: May 2012
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220-230 are good numbers for compression. As long as they are consistent between all four cylinders.
I'm on a walbro 255 pump and stock fPR. And no my tuner didn't mention any of that, only said something about the knock sensor going crazy after he tried to pull more timing. Something like that. And yeah I saw the boost plot, it did show 13 but my aem wideband is showed 10, I mmight'v missed it though if it displayed 13.
Originally Posted by leoxle' timestamp='1413388812' post='23370394
[quote name='CoolGuy094' timestamp='1413387991' post='23370375']
Seems low to me, especially AFTER a 15% correction bump. That would mean that your true number on a Dyno Dynamics before correction was sub-300 WHP. That just isn't right. I made nearly that on a Mustang Dyno with the stage 1 kit, Novi 1220.
What fuel pump do you have, and are you still using the stock FPR? Did the tuner mention anything about you running out of fuel or running out of injector duty cycle?
Did you see a plot of your boost pressure while you were there? The discrepancy between your boost gauge and his readings is odd; what boost gauge do you have?
Seems low to me, especially AFTER a 15% correction bump. That would mean that your true number on a Dyno Dynamics before correction was sub-300 WHP. That just isn't right. I made nearly that on a Mustang Dyno with the stage 1 kit, Novi 1220.
What fuel pump do you have, and are you still using the stock FPR? Did the tuner mention anything about you running out of fuel or running out of injector duty cycle?
Did you see a plot of your boost pressure while you were there? The discrepancy between your boost gauge and his readings is odd; what boost gauge do you have?
Now, my issue was because I was using a 320 LPH pump with the stock regulator. Your 255 LPH pump might not have the same issue since it flows less and the stock FPR can likely keep up with that flow without the base pressure rising. Only way to be 100% sure is to get a fuel pressure gauge at the rail. Not saying that its necessary or that its what's causing the problem. Just something to think about.
[/quote]
Thanks for the info, anything is helpful! I've never heard of a 255 having that issue and my tuner didn't mention the duty cycle or anything but I'll look into it.
Still super confused why im not making more power lol. Thinking of every possibility.