OKAY,

So I took three identical (as identical as you can on the street anyway) 2-3 pulls from the same on ramp. I did one with stock BPV hose routing, one with the tank bypassed only and then one with the tank AND solenoid removed (BPV straight to the intake manifold port). The mods to my car are:

1.) .035 restrictor on my boost control solenoid
2.) CIA catted DP
3.) HPT

Here is a screen shot of all three runs MAP's graphed against each other. I started the graph from the moment the peddle went to 100% again on the 2-3 shift to try and measure boost recovery as best as possible.

Click this:

http://www.ecimulti.org/scratch/HPTu...test_boost.jpg

It does appear that running with both the tank and solenoid bypassed, the car does recover boost faster between the shift. In the upper RPM ranges, I'd say its not possible to pick a winner. Although it looks like the NO TANK, NO SOLENOID line is slightly ahead they're all within the margin of error.

This is obviously NOT a scientific test, and I'd welcome people doing a lot more testing... but those are my results for tonight. If you're wondering why the MAP is flatlined, its because the MAP is pegged Also realize that this isnt a boost figure, thats the pressure the MAP is seeing at the intake manifold without ambient baro removed.

Summary: I'll be running no tank AND no solenoid until I see conflicting data.

 

Thank You Gimpster!!!! Nice work . This will help sift threw the placebo and see what's really changed when using this mod! Like you said .. I never thought peak boost would be effected much or at all , unless there was some other underlying issue before the mod.

I have noticed boost has smoothed out where it doesn't drop off after the initial spike ....at all anymore ....or not enough to pick up on. Thanks again!

 

Hey no problem, one of my favorite things to do is datalog and compare. I wish I could've done a bunch more pulls to back the data up, but maybe next year if someone hasnt posted more.

I guess the only question we need to answer now is: when does (if it does) the BPV leak? And if so, is that spring Dejon is pushing solve it?

Someone should do some logging w/stock spring and then with that Dejon to see if upper RPM boost drops. I'd wager the aftermarket spring does nada, but who knows!

 

I was just thinking it would be nice to see the results with a Dejon Spring installed. You never know, with the Dejon spring installed and the canister bypass, and/or solenoid delete, the spring might actually be a performance advantage.

I'm sure someone out there has there Dejon spring they took back out, maybe they could send it to you to compare.

Hint: To those of you that took your Dejon Spring out and just have it sitting on the shelf or in a drawer, spend $2 and mail it to this guy so he can get some logs and comparison.

 

i have the spring installed on my car was thinking about doing this mod but am not 100%

 

Thanks for taking the time to do this, a true "member" of this site. You just restored my faith in this site that much more I'm gonna bypass the tank and leave the solenoid connected, makes it less of a pita if the dealer ever wonders why there are hoses loose lol.

 

which part is the solenoid? the little black connector box correct... want to make sure im doing this correct

 

Yes, the lil guy with the connector is the solenoid.

Just connect the BPV to the intake manifold port with an extension hose (or run a whole new hose).

Remember to cap off the 2 vacant ports on the solenoid after doing this OR remove the line from the cold charge pipe and cap it down there. Otherwise its possible you could create a boost leak during certain conditions when the PCM is playing with the solenoid.

Good luck.

EDIT:

Wait, lets be clear on this. The best results I got were obtained by removing the solenoid AND the tank from the system. Just removing the tank from the system didn't build boost quite as fast.

So you'd want to hook it up like so:

http://www.ecimulti.org/scratch/bpvsolenoidbypass.jpg

Remove the yellow circled hose, and connect the red circled hose to where it was. Then remove the hose on the port closest to the radiator. Cap off the now vacant 2 ports and do whatever you like with the tank and its lines.

The other option is to remove the hose from the cold charge pipe and cap it off down there, which is what I did. My solenoid is sitting there like a dummy right now with zero control over anything.

 

so similar to the soltice forums guys "T" that they put in

 

I guess, except I have no use for a T. Just giving the BPV a normal reference port is all we're doing.

 

so= a bunch of rubber tube under the hood just hanging around?

 

If you consider about 5" of extra tube to reach the BPV "hanging around", then yes.

I've not removed the tank itself yet, but I removed all of the excess tubing. I might even get froggy and remove the solenoid + wiring too this Winter if I feel confident in these results. I'm very OCD and don't like solenoids / sensors hanging out when they have no purpose. My warranty is so shot anyway, no longer care.

 

what did you cap off the cold side piping with?

 

I have a large assortment of silicone caps on hand. Find them in the HELP! section of your favorite auto parts store. Oh and make sure you use a clamp or ziptie around the cap, you don't want the cap to blow off.

Like these:

 

This is excellent and well thought out. Thanks!

Like what was said earlier, now I wonder about:

1) stock
2) tank bypass
3) stock+spring
4) tank bypass+spring

I'd certainly take a stock vs tank bypass+spring at least though if that's all somebody could do. I'm fascinated to see if the tank delete and spring somehow go well together.

My car's not "on The Pill" (), so for me and many others some of this may not pertain to us.

 

Yah, honestly the fact I run a restrictor pill makes those results questionable at best for stock folks. The car literally builds 25.5+ (not sure how much exactly, need a mechanical gauge) of boost INSTANTLY. So fast I'd never notice this slight gain. It would bet the same for anyone running Trifectas infiniboost tunes. Since the PCM isnt tuned for that ridiculous onset of boost, it might be able to catch it.

I had the pill out for a couple days, but really missed the power and put it back in :P

So, for anyone running the pill, mbc or infiniboost... this might be your ticket.

Hope more people do some datalogging I'm a fiend for data and look forward to seeing more testing. Winter hath cometh here and the car is at rest

 

omg i gotta do this, this is why shifting was so slow to build up boost

 

so the line in ye;;ow goes where the red line is at??
isn't the red line to the stock bpv???
pm back plz

 

I did the EDAL mod from the solstice forums, which I assume is similar to this, running the Dejon spring, and have now started to notice some nasty BPV flutter. Keep an ear out for that. It could tear the flapper thingy (brain fart, whatever its name is, lol).

Might have to take a look at this. IMO, the Dejon spring has done NO harm, not sure about any gains, but I hold a SOLID 20 psi to the stock redline, and ~19 to 7k. I am NOT on the pill (my gf is though, lol... the one i don't have).

 

No, and I'm not sure I can make this any clearer but here I'll try-

1.) Unhook the red circled hose.
2.) Unhook the yellow circled hose.
3.) Put the red circled hose (BPV hose) where the yellow circled hose was (you'll need an extension or run a new hose to the BPV).
4.) If you want, remove the yellow circled hose and its companion off the tank below the intake manifold. Its companion is the hose closest to the radiator on the solenoid.
5a.) Option 1 - Unhook the hose on the cold charge pipe, cap it off and use something to secure the cap.
5b.) Option 2 - Cap all of the two open ports on the solenoid and secure them.



---

Try just dumping the solenoid from the system. Othwerwise the PCM can still indirectly funk around with the reference vac/bst signal a bit if it opens that solenoid (I'd think anyway). I did the EDAL mod back in march and experienced weird flutter and jerky conditions. Seemed fine last night, but I really didn't drive the car around much. At WOT it was fine, which is what I'd expect since with the EDAL mod the BPV sees pressure whenever the cars in boost.

Most every other turbocharged car in the world has no solenoid on the BPV, so doesn't scare me one bit to at least try it.

 

great work. i did this myself already with the dejon spring.

 

Let it tear baby!!! I'll just put the hoses back to normal and switch back the factory spring and have it replaced under warranty. Gotta love the GM warranty on there stage kits.

 

since i have a hks bov i think i have to run things differently. i dont know what i should do with the bpv hose and the hks hose. i ran the hks to the intake manifold and the bpv into the solenoid and got good results, but there is a lot of surge still. the car runs a lot better with a lot more throttle response. also, i don't have a cel any more. having the hks bov, is this the right setup? I ran the bpv to the solenoid to block it off temporarily since the solenoid is "dead". before i ran the bpv to the intake manifold and kept the hks in the solenoid but that just cut the hks off. since everything was capped off i decided to run the hks into the manifold because it was the only source of "boost" i could find.

http://i1019.photobucket.com/albums/...91014-1455.jpg

 

Heh, you're running an aftermarket BOV AND the stock BPV still? Whatcha thinkin' there?

 

sub'd
what do you guys thnk of aftermarket BOV's