Had questions about getting more boost

[ElSpeedDiablo]

I was wondering, I know I probably want to get a boost gauge, which I will probably do soon. I wanted to know what amount of boost can be pushed on our cars without it causing problems. I was told to buy a boost controller, what do you guys think? I have a few mods on the car, everything on the sig. I'm still learning a lot about my car so feel free to threat me like a n00b. I want to also run a cobb downpipe with the stock exhaust or should I get a cbe? Would my car smoke if I did this? Also I'd prefer for my car to not be too loud as the cops around here are no so nice, so I figured a downpipe would add some power but wouldn't make the car outrageously louder. Thanks for any info guys!

 

[AutoEuphoria]

You will need:

- Boost gauge
- DashHawk or similar (to monitor fuel pressure/AFR/etc)
- MAP clamp
- Boost Controller
- Step colder plugs
- Upgraded fuel pump internals (CDFP Internals)
- Upgraded bypass valve (BPV)

Then you should be able to run around 20 psi pretty safely. That's what I'm doing currently. Some run more, some run less. I might turn it down to 19 eventually..I'm still dialing it in.

With just a MBC you can increase it a couple of PSI, but you will probably run into boost/fuel cut if you linger over 18psi for too long. That's what the MAP clamp is for. The stock fuel pump is pretty weak, so you'll probably get fuel cut and/or unsafe AFRs at some point as well, which is why you should get the upgraded fuel pump internals. The step colder plugs helps take care of the hesitation around half way through the rev range. The upgraded BPV will help build/hold boost because the stock one is known to leak, even at stock boost levels.

The exhaust/intake mods will help everything breathe better, so it'll aid in spool time and overall power. Not really NECESSARY to run more boost safely, but a good addition to it. I am currently using the Corksport catless downpipe (wrapped), Corksport catless test pipe, SU silicone boost tubes (probably should get these or similar...the stock ones warp very easily), RPMC turbo inlet pipe, and CPE cold air intake along with the mods listed above.

 

[guitarsoloist87]

I hear that mbc do not control boost spike very well. Would it be better to go with something such as the greddy profec or use an aem boost/controller gauge? I don't really understand how they work. I hear the cp-e standback works great for boost control and for not getting boost spikes. Or what if I just adjust the wastegate manually? I don't really know if I can do that either. I'd assume the wastegate is already all the way open if people say it already has a boost controller. This car is way to wired for me to figure out. My turbo civic was much easier. But slower hahaha.

 

[AutoEuphoria]

There is basically no solution to boost spike.

 

[SomnoSpeed3]

So how much boost spike is too much for stock motor? I have Cobb AP and a MS CAI as my only upgrades. Also, what is number is considered consistantly high?
Thanks!

 

[AutoEuphoria]

If you have a Cobb AP you won't be able to use a boost controller...they don't mix well. From what I read, people have been going strong with boost spikes as high as 25psi...just as long as it's not holding there.

 

[ElSpeedDiablo]

Thanks for the info man! So with the current mods that I have what psi do you think my car is running on. Also if I got the cobb ap what map would be good for the current mods, I have? I've heard that with the ap you have to run the stock bpv, which kinda sucks. I want to get a mod soon, only have about $350 for now. I was just going to buy the cpe gauge set up, looks pretty oem. I was thinking on buying the cobb downpipe in the summer.

 

[AutoEuphoria]

Don't bother with that gauge setup...just get a DashHawk. Much less money and you can monitor more stuff/datalog/check CELs/etc. With your mods you can run up to 17.9psi...but if you run over that you will get boost/fuel cut. You will need a boost cut defender or MAP clamp to go any higher...or a tune. You might want to check out the CP-E flash that is supposed to get rid of all cut. That might be a good investment for you at this point.

 

[coyfish]

I wouldn't tinker with the stock boost unless you upgrade your turbo / internals. Lots of people are running MBC's with no problems but they are "risky." With mods alone your boost will increase.

Right now on stock boost and no tune im holding 18psi+/- 1 depending on conditions. I spike over 20 pretty much anytime I go WOT.

That being said my advice would be to simply mod your car 1st. You still have lots of basic bolts ons to do. Learn more and then make up your mind in regards to which direction you want to go (MBC vs tune).

 

[AutoEuphoria]

I wouldn't tinker with the stock boost unless you upgrade your turbo / internals.

I think that's a bit drastic. Running a few more PSI is not going to blow your engine unless you fail to take the necessary precautions to run it safely (ie, upgraded fuel pump)

 

[Mistersix]

breather mods alone will free up some boost.

the first thing i did was put a boost gauge on and was peakin 15.5 and tapering off from there in each gear.
now with my current mods i peak 18 and hold 15 or so.

you could consider trying to get the most outta the boost your currently pushin with some more mods. i'd think one would want the car breathing as best as possible before you go playin around with uppin the boost.

get that gauge on and see were your at!

 

[coyfish]

I think that's a bit drastic. Running a few more PSI is not going to blow your engine unless you fail to take the necessary precautions to run it safely (ie, upgraded fuel pump)

Some people have more luck than others. I personally think its better to upgrade the boost naturally with mods that increase efficiency. Just my opinion.

 

[MSMS3]

breather mods alone will free up some boost.

the first thing i did was put a boost gauge on and was peakin 15.5 and tapering off from there in each gear.
now with my current mods i peak 18 and hold 15 or so.

you could consider trying to get the most outta the boost your currently pushin with some more mods. i'd think one would want the car breathing as best as possible before you go playin around with uppin the boost.

get that gauge on and see were your at!

Great advice to the OP. Opening up the intake and the exhaust for freer flow will allow the ECU to "see" good conditions and allow boost to build up to about 2 more pounds, which is just about the top end of safe (not counting very short momentary spikes, which I personally think are harmless).

Upping boost without those mods first does not make a lot of sense because higher boost without the ability to flow more air into and out of the engine will just produce friction in the turbo compressor as it tries to push the air column past the restrictions. Friction=heat=reduced number of oxygen molecules per unit of volume=lower power.

That's thermal inefficiency and it happens when a turbo is trying to push more air than the system will flow. Compressed air produces heat. The stock intercooler tries to cool the air charge back down before it enters the engine. You can help it a bit with a bigger intercooler(more $$$), but a good CAI or SRI on the front end, and a catted or catless DP/RP into the stock CBE on the exhaust side will work wonders and is maximum bang for the buck.

Just my personal opinion. Others may differ.

 

[ElSpeedDiablo]

Wow thanks for all the responds. I'm thinking I should look into a dashawk. Best bang for your buck I guess. I'm still deciding on what to do after that maybe the cobb downpipe, sence I really like their stuff and sound nice. Too much stuff to take care of!!!

 

[tru-boost]

Actually my mbc has zero spike at all. I used to get a 2-3psi spike with the stock solenoids. It all depends on what mbc you use. A ball + spring mbc will spike. Most bleeder types dont. I use a turbosmart mbc and love it. 20-25 psi. Depending on gear and temp. Car runs like a mofo !!