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NEED HELP WITH KNOCK UNDER BOOST

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If you don't have access to race gas you can try Boostane. Cal Hartline had good results using that on a dyno tune session. You adjust the octane rating by the ratio. Don't know about the Lucas booster.
You are pressurizing your block if you have oil soaking the breathers. Put a check valve in the PCV line or eliminate it. I would do a pressure test on the intake to check for vacuum leaks. 132 is a little lean so there might be a minor leak.
I'm not familiar with the Red's chip. Not sure if a TT chip burned for your exact combo might have a better handle on the tune. At least it would be adjustable.
 
I went to the iskey website and couldn't figure out your cam (their website sucks). You list stock springs. They may not be strong enough for that cam. Can't tell without their seat pressure specs.
I attached the spec sheet that came with the iskey cam.
 

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I actually would leave it at 789 and see if the race gas gets rid of the knock if it doesn't or lowers the knock then I would bump it up some just to see if the change moves the car in the right direction he doesn't seem too off and red nows how to cut a chip.
The Translator for the 3" LT1 MAF has the Base setting at 3 and WOT setting at 0. Will adjusting the WOT to a richer setting help?
 
IMO . . . That cam is not the correct design for a turbo setup.
 
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I attached the spec sheet that came with the iskey cam.
I would contact iskey and ask what the recommended spring pressure is for that cam. Stock tb springs are just ok for the small stock cam. That cam may need a little more pressure to keep the valves from floating.
 
Will adjusting the WOT to a richer setting help?
It may not,which is why I suggested putting in some race gas.you get to a point where you will need octane regardless of how much fuel you throw at it.another alternative is to drop a little boost and see if the knock goes away,but to me 790mv and 4 degrees of knock the car is looking for octane if the drive train isn't involved
 
I see you had the engine done in 2012 and still is not running right?
 
I see you had the engine done in 2012 and still is not running right?
That is correct, during the break in period (2500 miles) the engine ran great but I did not test it under boost. I wanted to be careful not to damage the engine.
 
When you first started it, did you put any boost to it to seat the rings? That's a real important step.
 
When you first started it, did you put any boost to it to seat the rings? That's a real important step.
To the best of my memory with out checking my notes. The first time the engine was started after the rebuild, I ran it 2500 rpm +/- for 10 min. Changed the oil and restarted. The engine did not see any boost over 5 lbs till after 2000 miles.
 
Rings failed to seat??
OLD shop trik on fork lift engines: Hold it at 2K, shoot a "snort" of Bon Ami cleaning powder into the intake, using a ketchup squirt bottle. Bout 2 snorts, making the engine pull down, and the rings were as good as they were going to get.:jawdrop::smuggrin:
Dyno break in...15 mins @ 10% load. Check for leaks, noises, etc, and it's hammer time. As "broken in" as it's going to get.:D

Boost req'd to "seat" the rings? Suppose this same engine is n/a. Then what?
 
If you are sucking oil in (for whatever reason) it could effect your octane numbers. May not be the full reason for your knock but worth checking. Look into the intake and see if it's soaked in oil.
 
The engine does not smoke, exhaust pipes are gray color inside. The spark plugs show no oil residue. I did add .5 qt after about 1k miles with several hard pulls, 8-10 PDS boost.
 
Id make sure the Knock sensor is torqued down properly to 14# to rule that out for over sensitivity ..
 
IMO . . . That cam is not the correct design for a turbo setup.
I spoke with an engineer (Rod) with Iskey Racing cams and explained my knock issue and gave him a detailed description of my engine build. Rod said he has sold that "grind" cam to other Buick V6 Turbo customers with our issues. He asked why you think this cam is not correct? I asked him what is the recommended spring pressure for that cam, 100-120. Rod said he thought if it was spring pressure the engine would miss and backfire!
 
Since you haven't had a chance to rev it out at full boost (24+) you still don't know if the springs are strong enough. That will be determined.
 
. . . Rod said he has sold that "grind" cam to other Buick V6 Turbo customers with our issues. He asked why you think this cam is not correct? . . .. . .
Here is my opinion :D:

I am sure he sold the cam to other TB customers and it would be interesting to hear his (Isky's) theory and real world results with so much overlap in a turbo application?

If "I" wanted a lopey cam . . Sure . . I would use it. Not saying the cam is the source of the KR but think about the air making it to the O2 sensor under low load . . . countered by the neg impact on mass flow at boost from BP and reversal.

Hope you find the issue(s) as it can be very frustrating.
 
That cam doesn't have a lot of overlap. It's -16 degrees at .050". Same as other small cams of similar lift. Theoretical lift may cause an interference problem on the stock ex guides of not machined


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