boost spike ??

[das Boot]

ok this is whats going on, the m3 was dyno tuned and made some awsome power.
vic tuned it and he said that the most boost he saw on the data logs was 17.5 ish, but on the sreets if i lay into it 3rd and 4th it will hit 20 then stabalizes at 17.5 , i dont think i have any boost leaks, ive also heard that some boost guages are off about 2 lbs give or take , its on a 14 lb spring with 44 mm tial, im thinking that its making a shitload of boost when its spooling up then stbalizing, also from the looks of the dyno sheet there is no loss in power it just climbes like a mother. and thoughts.???:confused

one would think that when a set boost is reached it should stay right there especially on a big turbo like the gt-40

[Shuasha]

What controller are you using and what gain is it set at? If the gain is too high, it can overshoot and cause the spike.

[EstorilRoc3060]

I'm having the same issue/was. If it's a Greddy Profec I can help you out.

[davidtm5]

ok this is whats going on, the m3 was dyno tuned and made some awsome power.
vic tuned it and he said that the most boost he saw on the data logs was 17.5 ish, but on the sreets if i lay into it 3rd and 4th it will hit 20 then stabalizes at 17.5 , i dont think i have any boost leaks, ive also heard that some boost guages are off about 2 lbs give or take , its on a 14 lb spring with 44 mm tial, im thinking that its making a shitload of boost when its spooling up then stbalizing, also from the looks of the dyno sheet there is no loss in power it just climbes like a mother. and thoughts.???:confused

one would think that when a set boost is reached it should stay right there especially on a big turbo like the gt-40

check your boost leaked. i had the same problem on the dyno too. boost spike up over 31psi and taper of and stay at 27psi, i found a couple leak after dyno and fixed . right now i have to turn down my boost controler to stay under 30psi, because the 3 bar map sensor cut out at 31 or 32 psi. will turn up the boost when i get my 5 bar map

[das Boot]

What controller are you using and what gain is it set at? If the gain is too high, it can overshoot and cause the spike.

i have the e boost 1 connected to read boost but i havent figured out how to use it cirrectly so i have a manual boost controller hooked up. first thing first i guess i gotta pressure test , what is a good psi to start?