Testing EGBP

[Andy_Mac]

After a relatively cheap solution for testing EGBP. Anyone else hacked up a DIY solution before.

I'm intrigued to see what kind of backpressure the stock post turbo exhaust is actually generating rather than just taking the standard advice that it needs to be swapped out.

Could probably do something povo with a peak holding pressure gauge and some copper tubing for spacing to reduce the temp before getting to the sensor, but actually being able to log the difference across the rev range would be a nice bonus.

[Marky]

Have a hunt around here y0

http://www.autospeed.com.au/cms/search/index.html?keywords=backpressure&x=0&y=0

This is like the DIY bible, nebermind those MCM clowns this is the OG

[Guest]

Boost guage easiest way. Can fb you pics off my setup cbf uploading atm.

Is there any way you can swap an ecu line to map sensor and edit calibration?

[Andy_Mac]

Thought about just getting a long vac hose an feeding it into the cabin somewhere for a mechanical boost gauge then just recording the what pressure it gets at certain rev ranges and chucking it into an excell graph along with the standard logged figures aswell.

[Optical]

I drilled a hole through a spare sump plug and brazed about 30cm of brake line to it. At the end of the brake line a vac line attaches and leads to a spare MAP sensor for logging

[Guest]

[lachlan]

yea whay evowrx said . you can get those kits with copper tube at super cheap . the are for oil and boost gauges

[Andy_Mac]

Yea had been talking through it with him last night. Might go check out what the kits they have are like, or just braze something up with some copper at work.

[lachlan]

if u go to hcd you can get all the olives and every adaptor u can think of for single $

[Guest]

If you can log 5v its easy. If you can log 2x 5v you could get back to back results with 2 map sensors one map an other egbp.

[lachlan]

get a bit of cunning and use a differential pressure sensor from a tt

[Guest]

 lachlan said:

get a bit of cunning and use a differential pressure sensor from a tt

Talked to ross about that iirc wasnt viable.

[lachlan]

the budgo way to datalog is put the boost gauges near each other and record a video with your phone haha

[Guest]

 lachlan said:

the budgo way to datalog is put the boost gauges near each other and record a video with your phone haha

Yea thats an option but its easy to just watch boost guage. Sure it might not read high enough but when egbp hits a wall its blatantly obvious when it skyrockets and you know you have an issue.

[Andy_Mac]

Sweet. Theres a hcd in tga so i'll give them a go.

US guys can get 2x5v sources from doing the TGV delete, not sure how that applies to jap ones. I'll do some more research on unneeded inputs for the ecu.

[Andy_Mac]

 lachlan said:

the budgo way to datalog is put the boost gauges near each other and record a video with your phone haha

Was considering something like that but use the boost gauge for egbp and just get map logged from the factory sensor.

[Guest]

If you could do that it would be awesome and hopefully mean we start to see some more results on v7- stuff too. So if thats possible you could export rpm/map/egbp to excel and plot a graph?

[Andy_Mac]

Well with the tactrix it exports everything into excel format anyway so was just thinking about manually recording the egbp results into a table i don't really need which should then allow it to be easily graphable with virtual dyno

[Andy_Mac]

Alright so talked to a exhaust crowd who can supply and install o2 bungs for next to nothing so figured i might as well just get a 2nd one welded on. Would it be best to have it right at the top of the downpipe nearish the existing o2 sensor or further down near the other end of the downpipe? Don't suppose it'll make much difference other than having less perceived back pressure the further away it is due to the gas cooling?

Edited October 27, 2015 by Andy_Mac

[Guest]

Goes in up pipe.

[Guest]

Close to ex housing as possible and handt to have one 6in from housing in dp.

[Andy_Mac]

 evowrx said:

Goes in up pipe.

Was planning on starting with the downpipe to see what kind of pressure the post turbo part of the exhaust is generating. Trying to find tangible data to backup whether a full exhaust is needed or not.

Also for a twinscroll won't you need to get bungs installed on both paths of the uppipe, these ones don't have cats in the uppipes either so thats alot of the usual restriction gone

[Guest]

Pre is the big one. I didnt bother testing post as it was so low last time. Na one scroll would be fine. The big restriction is the turbine/housing not the 2.5" tb exhaust. At 227wkw vf22@20psi there was a marked difference between 2.5 and 3.

[Andy_Mac]

Aren't you still wanting to maintain a certain amount of pre turbo backpressure to help spool?

Is that no noticeable difference with stock or a big custom one? I'm kinda more interested in what keeping the stock turbo back exhaust is doing to the performance potential of it. And then the difference between the two when i eventually swap it out.

Or is the difference going to be low enough that i'm just wasting my time?

For the uppipe is it all that important having it right near the turbo or is at the bottom good enough? Potentially saves needing to completely remove the uppipe if it can be done at the bottom

[Guest]

Closer to 1:1 the worse the spool but doubt you will be under 2:1 at 18psi on stock snorter. Anything post just compounds the issue but worth doin. I didnt bother as with 1.26:1 20psi/6k and 20psi by 4k on 2l it didnt warrant checking.

With the vf22 it was worth swapping out to the 3in. Thats at a guess moving 38lb/m.

Im taking mine from collector just before up pipe cant see it changing much.