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Discussion Starter · #1 ·
I'm getting some pinging & knocking while in a higher gear, going 1K to 2K rpm's.. This happens on warm days, like 85 or better... I'm running 11.2 compression and I know this is part of the issue.

Questions.
1. looking to install a Vortex intake system to lower intake temps. currently have a Blackwing.. Will this lower intake temps better than Blackwing??

2. What octane booster can i use during the hot summer months only... I do not have close access to race gas(100)..

Any other recommendation welcomed.
Thanks'
 

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I almost never let my car get into the lower 1000 rpm range. It's really hard on an engine to lug it. Probably harder on it than over revving it. It causes a major strain on the bottom end. I usually keep my car about 2000 when cruising. If I'm on the highway, I'll let it drop lower but I never apply much throttle while at low rpms. If I need to accelerate, I drop down a gear or two.
 

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Discussion Starter · #3 ·
Norman,
Thanks for the input- I too try to do this, but at times or when driving around sanely( or with my kids-don't want to look like a lead foot with my kids), I do run 1.5K to 2K in 5th OR 6th gear... This is where I get pinking with moderate to light throttle openings...

This is were i need the help... I know it's because of intake temps, compression(11.2) or in need of higher octane and not having a true ram air system...
 

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It's probably all in the timing and fueling. Have you ever had your car tuned? I'm not sure you can get away from this. Usually when you are in higher gears and you give it some gas at lower rpms, most cars will knock a bit. Cooler air will always help a bit but the trick is probably the load, timing and fueling. Sorry I can't be of further assistance but if you had someone with a laptop and autotap or some other monitoring program, you could go out and see what she's doing first hand.
 

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Could be serious. You should not be having any knock at all. Are your Knock Sensor's working properly ?? You may also have a valve spring problem. You need to have problem diagnosed ASAP as it could be engine fatal.

Could be as simple as bad gas.

You didn't mention what the coolant and oil temps were in the hot weather. What are they when this happens ?? If the engine has been moded (11.2:1 CR) you may need a larger radiator and/or engine oil cooler.
 

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It's the tune!!
I found that a lot of tuners tune for the WOT dyno numbers and not much more!!
I found a tuner here that does the dyno as a baseline! He then drives and logs LT&ST trims on highway/intown, hot/cold start, A/C On/Off etc. He had the car all day and while the cool weather start is a litte rich, no more knock like you speak of that I had it out here when I first arrived from IL!!
The PCM can only pull so much timing out DJ!!
I'd love to have a gas pump out here that read 93!!

Ken
 

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Discussion Starter · #7 · (Edited)
Car has been tuned, but during cooler weather. LS1 Edit at Speed inc. WOT timing is 26 degrees.

Valve springs are new- 1.5K miles. I added octane booster yesterday- It did not knock today. Temps yesterday were 95, today 86.
I have a 160 degrees thermostat. Temps run - 180-190 while moving. Oil temps have been higher since it's been warmer- 195-205...normally 180-195.

Might a change from my Blackwing- sucking hot air from the engine compartment, to a Vortex help... Vortex is a true cold air system verses Blackwing without stout???
 

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jz06man said:
Car has been tuned, but during cooler weather. LS1 Edit at Speed inc. WOT timing is 26 degrees.

Valve springs are new- 1.5K miles. I added octane booster yesterday- It did not knock today. Temps yesterday were 95, today 86.
I have a 160 degrees thermostat. Temps run - 180-190 while moving. Oil temps have been higher since it's been warmer- 195-205...normally 180-195.

Might a change from my Blackwing- sucking hot air from the engine compartment, to a Vortex help... Vortex is a true cold air system verses Blackwing without stout???
If you want fresh air for the intake, there is a device for the blackwing called the ice-box that will separate intake air from engine compartment air. Basically goes over the blackwing and a cutout in the shroud is made to let fresh air in.

Mark
 

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Discussion Starter · #9 ·
2003torch- you are correct, i had this before but encounter issues with lean codes.. this is now a known problem with the Blackwing with shroud- i had to remove it... It did make a big difference in top end power, but it had to go...
I'm told to place a screen in the MAF and this might do the trick. I have not tired it.
Thanks
 

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jz06man said:
2003torch- you are correct, i had this before but encounter issues with lean codes.. this is now a known problem with the Blackwing with shroud- i had to remove it... It did make a big difference in top end power, but it had to go...
I'm told to place a screen in the MAF and this might do the trick. I have not tired it.
Thanks
Interesting as I am having some lean issues now after the H/C install.
 

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Discussion Starter · #11 ·
torch,
Did you retune after H/C.. This is a must. Also do you have a Blackwing with Icebox?
 

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jz06man said:
torch,
Did you retune after H/C.. This is a must. Also do you have a Blackwing with Icebox?
You are correct that a tune after such extensive work as H/C is a must and yes I did so. I also have the icebox. After much troubleshooting I found this:



After repair and about 150 miles performed a scan. Found the lean condition much improved but will do another scan in a few days to confirm. Don't think the PCM need more than 100 miles or so to readjust. Could be wrong though, will see.

Mark
 

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Discussion Starter · #13 ·
Mark,
you could reset the fuel trims by disconnecting the battery for 30 mins.. then drive the car for 30-75 miles.. the PCM should relearn the short and long term fuel trims much quicker.

Good luck,
John
 

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jz06man said:
Mark,
you could reset the fuel trims by disconnecting the battery for 30 mins.. then drive the car for 30-75 miles.. the PCM should relearn the short and long term fuel trims much quicker.

Good luck,
John
Thanks for the subjestion but I already have a new tune in the works as many other factors have changed also such as injector duty cycle has been reduced by 5%.

Mark
 

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Discussion Starter · #15 ·
I installed the Vortex on Friday.... The next day ,it was very hot-100!

I ran the car slowly and very fast... Did not have any ping issues at all. I guess i was right and the hot air was affecting intake temps and thus giving me ping- and reduced power.
Vortex- big difference over the Blackwing!! I can wait until cooler weather... Power should be up 1% or 2%.
 
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