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Forward Facing Plenum using Standard ECU

Started by VLC-57L · 15 June 2010 · 48 replies

Preserved from CalaisTurbo. Original authors and dates are shown; archived members are not current Holdcom accounts.

VLC-57LArchived member
Hi guys, in regards to using a forward facing plenum (for shorter and much neater cooler piping) but maintaining the use of the Standard Turbo ECU. Has anyone done this? I have looked through as many threads as I could, and searched like crazy. I see most who use the Rajab, JD Custom plenums etc use an aftermarket ECU (mainly because they are trying to achieve much bigger horsepower anyway, which makes perfect sense) I understand all the factory sensors must remain (i'm no dummy when it comes to this). But I am currently building a nice Standard Calais Turbo. I have spent many hours relocating the fuse/relay wiring inside, replacing the standard washer/over flow bottles, all to neaten up the engine bay. I want to run shorter cooler piping and would like a decent looking forward facing plenum, not a cut shut N/A plenum job. I have just heard people saying the flow to the further away pistons is real bad. Plugs foul etc etc. Is it really that bad? and will it effect the standard ECU tuning much? In my mind, once on boost, the plenum is under pressure anyway, but maybe it idles rough. Any one tried this? I can get a plenum made up quite easy, I have a relative who does cast alloy fabricating, and all sorts of metal work. I just didn't want to have it all done, and find out the car runs like a dog. After market ECU is not an option. Not interested, I am only planning to run say 10-12 PSI max. Just a nice cruiser, with a neat (aftermarket looking) engine bay. Any information or past attempts would be greatly appreciated. Thanks in advance. ---------- Post added 15-06-10 at 14:47 ---------- Wow no suggestions at all?
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BT130TArchived member
i have reciently done this used a custom plenum with standard computer and trust me its well worth it not only are the cooler pipes shorter and it looks better but it pulls much harder and the pedal is so much lighter and more responsive.
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SRBMUUArchived member
as long as you keep your sensors at the back of the plenum it can be done ive just done it couple of days ago it isnt hard you just gota figure out what parts you need and what parts you dont
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HTURBOArchived member
Why don't you buy one of these. http://cgi.ebay.com.au/VL-TURBO-PLEN...item3ca6549464 (http://cgi.ebay.com.au/VL-TURBO-PLENUM-MANIFOLD-MIRROR-POLISHED-RB30-VLT-Stg3-/260488598628?cmd=ViewItem&pt=AU_Car_Parts_Accessories&hash=item3ca6549464)
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vanstrienArchived member
Quote: Originally Posted by SRBMUU [View Post] as long as you keep your sensors at the back of the plenum it can be done ive just done it couple of days ago it isnt hard you just gota figure out what parts you need and what parts you dont care to tell us which ones u need and which ones you dont?
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HTURBOArchived member
If your planing on such a small boost levels. A standard RB30ET plenum has been proving time & time again. But if your after smaller piping length chat to CPC. http://www.calaisturbo.com.au/showthread.php?t=46459
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Vl_CalaisArchived member
Hey all, anyone had any experiences with those eBay Plenums? They look like a decect product that's well priced; always been a little sus with buying stuff off eBay though. Thoughts???
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SRBMUUArchived member
ill try get photos up this w.e to show u what is needed. car is a drift hack so i ****ed off all the emissions gear and a couple other things
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hatto.69Archived member
i have a cpc plenum and standard ecu im just wondering what you did with the sensors that were attached to the standard plenum chamber?
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NackerzArchived member
Quote: Originally Posted by Vl_Calais [View Post] Hey all, anyone had any experiences with those eBay Plenums? They look like a decect product that's well priced; always been a little sus with buying stuff off eBay though. Thoughts??? Hey mate I got one of those plenums from bugzy and it took me like 3 months before i got it, and not too mention all the hidden costs i got stung with too. Heres a pic of what it looks like with an xf throttle body Some original photos have not been recovered yet.
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Vl_CalaisArchived member
Hidden cost....Tell us more bud! Save us all from getting stung!
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VLC-57LArchived member
Thanks for the replies guys. Yeah I have seen those ones on ebay and yeah he does do a version that allows you to bolt the IAAC valve in it's original spot. I know all the vacuum lines that are needed to be kept and the ones you can pi$$ off. The water line's don't need to be there also (that was just a typical factory thing to help heat everything up and run smooth from cold) What my main concern was, does it run just as good and if not better? and also is anyone finding starvation in the 5th and 6th pistons? (the ones now furthest away). According to BT130T and SRBMUU, I got my answer that it does run fine with a standard ECU and if anything much more responsive due to less cooler piping (less lag) but have you guys notice that 5th and 6th pistons run richer at all? I have just heard some people say they do, others say they don't. In my mind, the runners are all so close that once your on boost, they will all have the same amount of flow anyway (especially on low boost applications) The expensive Tuned Length plenums serve their purpose for race and higher boost applications, as port lengths do become a major factor for the flow under so much boost. ---------- Post added 15-06-10 at 22:21 ---------- Thanks for posting those pics Nackerz. That plenum looks a lot better bolted up on your engine, then it does in the pics on ebay. Forward Facing plenums are such a nicer neat way of tidying up the engine bay. I'm not going for a performance factor here, just a neater layout and using less piping. More inputs on this topic are still welcome.
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boosted_wagonArchived member
If u run fwd facing plenum and use an xf tb or similar u don't need to run the standard crap on the back of the factory plenum. It's main purpose is for idol control which is adjusted with the xf tb anyway. I've done this on the last 3 setups and Alondra with a massive Wade cam hi mount t66 wasn't a problem at all
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NackerzArchived member
if i had of known that i wouldnt of got the valve on the back left there, but ohwell! just eaten tea then will post up what it cost me
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VLC-57LArchived member
Quote: Originally Posted by boosted_wagon [View Post] If u run fwd facing plenum and use an xf tb or similar u don't need to run the standard crap on the back of the factory plenum. It's main purpose is for idol control which is adjusted with the xf tb anyway. I've done this on the last 3 setups and Alondra with a massive Wade cam hi mount t66 wasn't a problem at all Are you just leaving the wiring that normally plugs into that valve and having no signs of effects at all? I can't say I have ever had my engine running and un plugged that to find out lol. I can't run my engine at the moment (still in the process of relocating my fuse wiring, and setting up a new fuse block) Nackerz - I still think you've done the right thing by having it bolted on the back there. Better to be safe than sorry (when it comes to using the factory ECU and sensors) Boosted_Wagon - you do make a good point there, it is only a solenoid that adjusts idle control, but I wasn't even going to even use the XF Throttle body, which means I should still run mine. Though like you said you've done this 3 times before, thanks for the info Greatly appreciated. Some original photos have not been recovered yet.
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NackerzArchived member
I paid $589 for the plenum all up $450 plenum $34 postage $35 to suit XF throttle body $35 for bracket $35 to leave the iac valve on the back Then on top i paid $170 for the semi poleshed XF Throttle Body So all up I paid $759 vlc-57l I have a nistune in my na ecu
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ISL33PArchived member
honestly, you dont need the IACV. BT130T has one of my old style plenums at the moment. NA turbo conversion and NA computer with IACV plugged in and prior to the instal of the aftermarket ECU, had no problems with the idle. The easiest thing to do it simple adjust the idle through the throttle body. If you are just after shorter piping the throttle body on the front of the standard plenum is the easiest and cheapest way by far. Hatto - I have replied to your pm
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madrx3boyArchived member
this is probably a stupid question, but what do I do with all the standard sensors/valves on on the factory plenum once i get an aftermarket ecu? I plan on getting the plenum modified to front-facing, and using a KA24 throttle body, with and aftermarket ECU (Link G4), do I need to keep any of the sensors/valves in the plenum, or do I only need vaccuum lines (eg to my brake booster/fuel reg/wastegate etc)? cheers
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VLC-57LArchived member
Quote: Originally Posted by madrx3boy [View Post] this is probably a stupid question, but what do I do with all the standard sensors/valves on on the factory plenum once i get an aftermarket ecu? I plan on getting the plenum modified to front-facing, and using a KA24 throttle body, with and aftermarket ECU (Link G4), do I need to keep any of the sensors/valves in the plenum, or do I only need vaccuum lines (eg to my brake booster/fuel reg/wastegate etc)? cheers Spot on there mate. Those sensors only talk to the factory ECU. So if you are going aftermarket big bonus for you. All you will need is the vacuum lines for Brake Booster, Fuel Reg, Wastegate a Boost gauge etc etc.
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madrx3boyArchived member
Quote: Originally Posted by VLC-57L [View Post] Spot on there mate. Those sensors only talk to the factory ECU. So if you are going aftermarket big bonus for you. All you will need is the vacuum lines for Brake Booster, Fuel Reg, Wastegate a Boost gauge etc etc. sweet Some original photos have not been recovered yet.
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