engine Knock

2500avalanche

2500avalanche

Well-known member
I need some help figuring this out.
I took the ty out today, and Brandon put it on the scan tool. Under about 7 lbs of boost, I was getting between 5-7 knock count. This is at about 50% throttle. I have replaced the entire ignition system. I also had it on T120 setting. I didn't hesitate or anything, just noticed the knock. Any hints? Is this normal?
I am running 93 octane fuel in it. Brandon is going to send me over the file to post, but any hints would be great.:tup:
 
91blazins10

91blazins10

Active member
Re: engine KNock

Re: engine KNock

Im guessing you have a 3bar map sensor installed correct? Stock injector ultimate chip needs 50psi base fuel pressure, with the vac line disconnected. You have a adjustable FPR and walbro 255 fuel pump correct? If not put the stock chip back in, otherwise your gonna be looking into a engine rebuild.
 
Big Mike

Big Mike

New member
Re: engine KNock

Re: engine KNock

What are your plugs gapped at? Have you ever checked your initial timing with tan wire disconnected? It needs to be set to 0 degrees.
 
2500avalanche

2500avalanche

Well-known member
Re: engine KNock

Re: engine KNock

91blazins10 said:
Im guessing you have a 3bar map sensor installed correct? Stock injector ultimate chip needs 50psi base fuel pressure, with the vac line disconnected. You have a adjustable FPR and walbro 255 fuel pump correct? If not put the stock chip back in, otherwise your gonna be looking into a engine rebuild.
Click to expand...

It has the ultimate. As for fuel pressure, what do you mean by 50 psi with the vac line disconnected? What line is it?
I do have a walbro 255 and FPR.
 
Richard Le

Richard Le

New member
Re: engine KNock

Re: engine KNock

2500avalanche said:
It has the ultimate. As for fuel pressure, what do you mean by 50 psi with the vac line disconnected?
Click to expand...
Yes, 50 psi with the vac line to the FPR disconnected and plugged. Don't forget to re-connect it after the pressure has been set.
 
2500avalanche

2500avalanche

Well-known member
Re: engine Knock

Thanks for the info. If anyone can help, I would love to send them the datamaster file to look over.
PM me your email, and I will send it your way. Thank you for your help!
 
WyoSyclone

WyoSyclone

Active member
Re: engine Knock

IMHO I think you may be looking at a 'normal' condition.Building boost at certain part throttle conditions can bring on a fair amount of knock. Think about going down the road in a normally aspirated car.... you can almost always make it knock/ping if you just load the engine down a fair amount with increased throttle.

How much it knocks is probably the key... anytime we've switched engine components and then added a new chip we're really opening ourselves up to knock conditions..... this is what I really like about Code59.. you have the ability to log, and then go in and minimize/correct the problem.

I doubt that at part throttle you can entirely eliminate the knock.... I've tried to make sure mine stays below 2 degrees of KR under those conditions. I would imagine you'll have to change the tune to get it under control..... just my :2cents: :D
 
Aeroking

Aeroking

e.i.
Re: engine Knock

the knock spiked in and out. I'm hesistant on saying that it is a problem, because, the run was at 50% throttle in and out, and only about 7psi. I'm not familiar with the ultimate, so i wasnt sure on what the FP should be, and what boost levels should be seen with each setting. But it runs smooth. :tup:


any idea what the knock threshold is on an Ultimate? does it pull timing or boost?
 
turbodig

turbodig

Active member
Re: engine KNock

Re: engine KNock

Richard Le said:
Might want to try a lower setting, such as T1-15 or T1-16, until the problem is resolved. No, knocking is not normal.
Click to expand...

On most pump gas, 20 psi is gonna be a tall order, unless things are working perfectly and fuel is in tune.

In other words, I would expect t1-20 to knock on pump gas.
Particularly in light of the fact that they didn't always have the most stable boost control.

Turn it down to one of the 16-17 psi settings, and check again.
 
2500avalanche

2500avalanche

Well-known member
Re: engine KNock

Re: engine KNock

turbodig said:
On most pump gas, 20 psi is gonna be a tall order, unless things are working perfectly and fuel is in tune.

In other words, I would expect t1-20 to knock on pump gas.
Particularly in light of the fact that they didn't always have the most stable boost control.

Turn it down to one of the 16-17 psi settings, and check again.
Click to expand...

20 would be the max PSI allowed (I only got to 7-8). T1 is designed for 93 octane, which is what I am running. I will turn it down to T117 though!:tup:Thanks for the help!
 
Aeroking

Aeroking

e.i.
Re: engine Knock

question. If the Ultimate has a 20psi setting, then wouldn't the chip need a 3bar map? or can you run an Ultimate to 20psi with the 2bar?
 
Ty1642

Ty1642

Member
Re: engine Knock

Aeroking said:
question. If the Ultimate has a 20psi setting, then wouldn't the chip need a 3bar map? or can you run an Ultimate to 20psi with the 2bar?
Click to expand...

The Ultimate does require a 3-bar map. I didn't see 2500Avalanche confirm anywhere above that he does have one.
 
2500avalanche

2500avalanche

Well-known member
Re: engine Knock

OK, I got the MAP SENSOR part out, but there is no part number on it. Where I have seen others that have the part number near where the nipple is for the vacuum, there is no part number, however, the vacuum tube was disintegrated. On the opposite side than the nipple side, it has the numbers 466 in teh plastic, and where the connector is, it has the numbers 749 9246. Any hints out there? I cant tell if this is a 2 bar or 3 bar

EDIT: Ok, On the Map Sensor, it has the numbers
PBT-GF30
9576-2
 
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