understanding more about boost spike

[SpyderDSM]

I have done a lot of searches for boost spike in the forums. I have found plenty of information but I just wanted to clarify a few things:

1) a typical stock t25 will normally begin experiencing boost spike when the car is modded through pressure fluxuations (exaust, icps, MBC)

2) small amounts of spike are not worth worrying over but spikes of 4-6+ should be delt with.

3) boost leaks can cause excessive spiking.

4) the correct installation of boost gauges and MBCs will help resist boost spike

5) boost spike +bogs WOT could be a question of running lean or rich, and experiencing a misfire

6) cold weather can increase your chances of spiking

If this information is right, I feel as though I may not know where to go for help on this issue:

I began expriencing spikes some time ago, when on the stock BCS, this was after I had done all the maintenance. The car had a full 3" turboback and intake pipe and filter at that point. Since then I have upgraded the BOV to a greddy rs, the uicp and licp are both hard pipes, I have a boost, egt, and fuel pressure gauge, and have just installed my MBC.

All these things have been extensively researched before their install and I am still having problems with boost spikes dispite doing a BLT (or 5) before and and after each installation.

Currently my boost is set between 14 and 15 and holds well at those levels. I can boost slowly up to these levels (or gradually) and then when I floor it, it WILL NOT SPIKE. However, when I slam it in 1st or 2nd from the bottom of the gear I will experience spikes of up to 22, but usually around 19, and then the boost will settle and not fluxuate after about a second or two. When in 3rd, 4th, or 5th and I do the same (floor it from the bottom of the gear), I will usually feel the equivalent of a bog or misfire right before the boost settles down. This may also happen a couple times in the same gear.

So - for anyone who has the patience for this problem - what should I do? I will have access to a logger in April though I am not entirely sure what to look for in order to fix this, though I do understand the significance of running rich or lean, etc.


THIS WAS A VERY LONG POST BUT I AM TRYING TO GIVE AS MUCH INFO AS POSSIBLE, SORRY FOR THE ANNOYANCE!

thanks very much guys

 

[SpyderDSM]

no one has a suggestion? please help

 

[anteversion]

porting the turbine housing inlet and the wastegate hole help great fro boost spike/creep.
also some cheap MBC are causing spike a lot

 

[Dsmj89]

I am having the same problem with my t25. I am spiking to 20+psi, there fore i always see myself having to let off, pretty much my gas pedal is it's own boost controller. I do have a small boost leak at my s-pipe and i am hoping after i get that fixed it solves my problem. Have you tried checking if your wastegate arm isn't stuck closed ?

 

[SpyderDSM]

I am having the same problem with my t25. I am spiking to 20+psi, there fore i always see myself having to let off, pretty much my gas pedal is it's own boost controller. I do have a small boost leak at my s-pipe and i am hoping after i get that fixed it solves my problem. Have you tried checking if your wastegate arm isn't stuck closed ?

will do asap and report back.