new billet wheel dbb turbo and alky

[qwks6]

I really love my new 6262 billet wheel ball bearing turbo. However, I have been experiencing something I need to have resolved. I am having a little issue with some knock. After the new turbo was installed I started having some mid-boost issues. Car had no problems with knock prior to the swap. I am using a chip custom burnt for my current setup.

Here's the problem. When I step on it about 3/4 throttle it spools very fast and gets knock immediately around 10-15 psi. However, if I feather it up slowly there is no knock. I can feather it up to WOT where I've seen high 700's on the scanmaster with zero knock retard at 20psi. With razor's alky kit when I bring boost up slowly the LED goes red around 5psi, and green around 8-10 psi. I haven't messed with the internal knobs on the pac since I bought it. I'm thinking it's time.

So, what I'm thinking I need to do is ramp the alky up quicker. Does this sound right? How do I go about getting a quicker ramp up while spraying the same amount at higher boost levels? Hope I'm clear enough with the question. Thanks for any help.

 

[turbo nasty]

Im having to replace my fuel pump now because of a very similar issue.

Make sure your fuel psi is at the proper risen rate for given boost psi. Mine was 15 psi low at WOT.

As the fuel ramps up the pump cant keep up demand and through that time the alky is still coming up and there lean dip from lack of fuel causes the knock. HTH

 

[QUIP'6']

I really love my new 6262 billet wheel ball bearing turbo. However, I have been experiencing something I need to have resolved. I am having a little issue with some knock. After the new turbo was installed I started having some mid-boost issues. Car had no problems with knock prior to the swap. I am using a chip custom burnt for my current setup.

Here's the problem. When I step on it about 3/4 throttle it spools very fast and gets knock immediately around 10-15 psi. However, if I feather it up slowly there is no knock. I can feather it up to WOT where I've seen high 700's on the scanmaster with zero knock retard at 20psi. With razor's alky kit when I bring boost up slowly the LED goes red around 5psi, and green around 8-10 psi. I haven't messed with the internal knobs on the pac since I bought it. I'm thinking it's time.

So, what I'm thinking I need to do is ramp the alky up quicker. Does this sound right? How do I go about getting a quicker ramp up while spraying the same amount at higher boost levels? Hope I'm clear enough with the question. Thanks for any help.

not to change subject but how do you like the bb 6262? what was your prior turbo and was there a noticable increase in power switching?

 

[qwks6]

I was using a cpt-61 turbonetics single ball bearing. The 6262 feels like it's making way more power, and has much quicker spoolup.

After researching this problem a bit I'm leaning towards false knock and trying to figure out how to find it and fix it. Nothing is ever simple.

 

[QUIP'6']

I was using a cpt-61 turbonetics single ball bearing. The 6262 feels like it's making way more power, and has much quicker spoolup.

After researching this problem a bit I'm leaning towards false knock and trying to figure out how to find it and fix it. Nothing is ever simple.

thanks for the info. sounds like false knock but you cant be sure since it didnt do it before. maybe when changing the turbos your downpipe maybe hitting now because it wasnt put in the same spot. just a thought

 

[qwks6]

I was thinking either the geometry of the new turbo or more violent twisting of the engine.

 

[JayC]

So, what I'm thinking I need to do is ramp the alky up quicker. Does this sound right? How do I go about getting a quicker ramp up while spraying the same amount at higher boost levels? Hope I'm clear enough with the question. Thanks for any help.

You get an ISAC. Thats one of the features the ISAC has. Methanol is not delivered linearly. You have the basic base setting vs boost rise but you also have sliders you can use to tweak out the rest of the methanol curve through the RPM range.

You could also take advantage of the boost controller in the ISAC to tie everything together. The ISAC provides a nice failsafe if you run out of methanol or the car leans out.

 

[Razor]

You dont need alcohol for low boost and it will not fix false knock.

Alcohol is to be used to suppress real knock that is octane related and not tuning related. If the car knocks at 10 PSI.. you have other problems.

If your motor is lean at 3500 RPM's, then fix that in the chip tuning. Once you have proper air fuel/timing and it knocks.. then add alky to fix that.