Over boosting.....

So since i have installed my bellmouth invida DP and HKS CF Tip turbo back when i am at low RPMS in 3-5th gear and give it some gas the boost spikes to high lbs. What is causing this ? my guess was the bellmouth DP but not 100% sure, any way i can fix it without purchasing a new DP ?

Are you tuned?

Have a stage 2 AP tune for the turbo back

burtonxridaxx said:

Have a stage 2 AP tune for the turbo back

Click to expand...

Protune or the OTS map that came from the AP?

its a stage 2 93 oct map off the AP, so from the website. not a protune

burtonxridaxx said:

its a stage 2 93 oct map off the AP, so from the website. not a protune

Click to expand...

Ok. Does your new Invidia downpipe have cats?

no sir it is catless

burtonxridaxx said:

no sir it is catless

Click to expand...

Ok, good.

Now, Cobb's OTS maps support Cobb's downpipe or more specifically, a downpipe with catalytic converters. The lack of catalytic converter may cause an overboost situation.
You might try the LWG (low wastegate) map and see if that helps. It will be preloaded on your AP.
if not, I would say to get tuned for your downpipe or switch to Cobb's or another's with a cat.

If I remember correctly, Cobb's standard OTS Stage II maps are designed for a catted downpipe. I remember them
having a separate tune for a catless dp, and there being a note next to it stating that a 'catted dp tune' with a catless
dp, is known to cause boost spike, which I'm pretty sure is what you are experiencing. I recently checked their OTS
tune archive and I don't see that tune listed anymore. I'd imagine that over the years, it was modified and named something
else.

Either way, what I'm getting at is, you can run the LWG map like Spamby suggested and in the meantime contact Cobb and
ask them if they still have that tune, etc. etc. Inquire as to whether their current tunes are optimized for a catted dp or
if they are okay catless. Mention that you are seeing "boost spike". They may be able to hook you up.

In the end, what you really need is a protune.