RPM and Speed bounce/boggles

Ms3orDie

Greenie N00B Member
I am not sure whats wrong but when im in 2nd and 3rd gear driving like a grandma, from 2k to 3k on the rpm, the rpm sorta struggles to get to 3k. The rpm bounces, you can hear the engine sorta struggles to get to 3k and you can feel it throughout the entire car. But if i dont drive like a grandma and step on it to get boost, it drives fine. Looking around the engine bay i am not seeing anything that could cause this issue. Could it be because I have all damond mounts? Maybe someone has dealt with this before and can chime in? Appreciate it.
 
Definitely not because of your damond mounts.

What's your fuel pressure send Afr? Try taking some logs also how old are your spark plugs
 
Do you have a logs, have you checked fuel pressure?
Definitely not because of your damond mounts.

What's your fuel pressure send Afr? Try taking some logs also how old are your spark plugs


Here is a log for my drive home from work. The plugs are maybe over 10k old. I do have new ones and am planning to install them this weekend when I do the valve cleaning work and CS Injector Seals. I noticed when the boggle happens, the AP AFR reading is very sporadic jumping back and fourth from any value between 8 to 20 very fast. But, my wideband AFR gauge bounces between 14-15.
 

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Did you jiggle the wires while the car was running

How much boost are you able to hit?


I jiggled the wire this morning and no changes. Max boost is set for 25 and i was able to hit 24 psi. I am not sure if i am saying this correctly but it seem to take long to hit 24. I hit 24 at the end of my powerband. If that makes sense.
 
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I am running a turbosmart bov. Ive noticed if i move the nozzle for soft/hard it affects the boggling that i mentioned.
That's exactly it. The tension is too soft and the valve is hanging open causing a massive vac/boost leak.

Need to fine tune the valve, on that one you're likely going to have to crank it all the way down iirc.
 
That's exactly it. The tension is too soft and the valve is hanging open causing a massive vac/boost leak.

Need to fine tune the valve, on that one you're likely going to have to crank it all the way down iirc.
So crank it all the down to soft? I have it in the middle right now.
 
I had this issue with my Precision 50mm BOV, I ended up needing another washer to get the pressure right for when my car pulls 11 psi of vac at idle and clutch in. This is not uncommon for bigger BOV's to need adjusting like that. If you can't seem to get it right you might be able to add a washer as well to increase the spring tension.
 
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