Manual Boost Controller vs Remap

[monkeylover]

Hi All

Aside from the obvious price saving, has anyone opted for the boost controller over an ECU remap?

[Goochie]

I doubt it. A remap doesnt just adjust the boost, there are several different maps that are tweaked.

[DGW]

Which boost controller?

[Stuart_J]

A boost controller on its own wont increase the boost you have now, it just means when set on max its as you have now & when you turn it down you will have less

[landwomble]

mate with his 1.8T mk4 golf chose the optional boost controller from jabba when they did the remap. it's very neat, hidden in the ashtray. in practice though, he just leaves it at max, i wouldn't bother...

[monkeylover]

I was going to buy it from Dawes Devices: http://www.3barracing.com/product_6.htm

Obviously,once the required boost levels are achieved I would Loctite the thread to stop it from sliping and getting boost spiking

Stuart, i was under the impression that with the manual boost controller it increases the allowed amount of boost before the actuator releases the pressure through the wastegate by reducing the presure to the actuator. Are you saying that the car is already running on the maximum boost level available before the ECU fuel defence cuts in???

[bengie]

the ecu on the 1.8T is much more advanced than the ecu of say the rover turbo's and other older petrol turbo engines.

simply increasing the boost won't work and it will either shut down completely, run like a POS or go into limp mode so give you minimal power to move the car.

[DGW]

mate with his 1.8T mk4 golf chose the optional boost controller from jabba when they did the remap. it's very neat, hidden in the ashtray. in practice though, he just leaves it at max, i wouldn't bother...

I had one fitted recently and plan to use it reduce the boost for: town driving; when road conditions are slippery; when SWMBO is driving (she hasn't noticed yet); and when using 95RON rather than 98RON which the car was remapped for. If the car was still under warranty it could be used to reduce the performance to near standard when the car goes to the dealer. I am sure there are other occasions when it might prove useful too.

[Stuart_J]

mate with his 1.8T mk4 golf chose the optional boost controller from jabba when they did the remap. it's very neat, hidden in the ashtray. in practice though, he just leaves it at max, i wouldn't bother...

The only plus is I believe it helps prevent over boosting if something else goes wrong but I might be corrected on this by those who are more knowledgable. Like your M8 Ive got the Jabba one on mine & even with 350 bhp I still tend to control power with the right foot. The only time I turned it down was when the clutch was on its last legs & I had to limp to Peterborough for a new one

[bengie]

i actually use my jabba boost controller quite a lot. turn it down when pootling round town then whack it up fora bit of fun. but when i lend my car to someone or it goes to a garage it gets turned down and unplugged

[rs_chris_uk]

tried one of them devices before and they dont work! the ecu controls the boost and still onlys gets 7psi!

in the end up i bite the bullet and got a remap and never looked back!

[Sheaf]

Has anyone got a clear diagramatical explanation of what goes on with the 1.8T engines regarding boost?

I'm confused at how a BCV can lower the boost from std.

In most engines the BCV goes inline between the inlet manifold and actuator. The pressure in the manifold will open go to the acutator and open the wastegate at a certain pressure.

The BCV works via a spring preventing the pressure from reaching the actuator until a certain boost pressue is reached.

If the valve is closed, then very high pressures will be obtained before the wastegate is opened... if the valve is set too low, then it will open early, and the turbo will simply run actuator pressure. Therefore, it's phsically impossible to run lower than std boost.

I therefore dont understand how you can run lower than std boost without removing the normal boost control valve, which I'm presuming you're not doing.

I'd be interested to know what goes on regarding this.

I know it's normally controlled by the ecu, however I'd have thought that the ecu should be able to cope with higher than std boost in its normal state and adjust to suit. Of course a remap will modify the ignition/fueling more and optimise futher mind.

[bengie]

the ecu controls boost, to control the boost you need to control the ecu. simple as that.

things have moved on from the technology of 25years ago where turbo's were simple things controlled by simple methods, the ecu knows hundreds of different things that are going on in and around the engine all at the same time down to altitude, air pressure, air temperature, air moisture levels, air temperatures, fuel pressure, fuel temperatures the list is nearly endless as it will measure all these different things along with many many more at different places in the engine and if something reports a big variation from a previous sensor then it will virtually shut down as it thinks that something is wrong.

[MaxLugo]

Has anyone got a clear diagramatical explanation of what goes on with the 1.8T engines regarding boost?

I'm confused at how a BCV can lower the boost from std.

In most engines the BCV goes inline between the inlet manifold and actuator. The pressure in the manifold will open go to the acutator and open the wastegate at a certain pressure.

The BCV works via a spring preventing the pressure from reaching the actuator until a certain boost pressue is reached.

If the valve is closed' date=' then very high pressures will be obtained before the wastegate is opened... if the valve is set too low, then it will open early, and the turbo will simply run actuator pressure. Therefore, it's phsically impossible to run lower than std boost.

I therefore dont understand how you can run lower than std boost without removing the normal boost control valve, which I'm presuming you're not doing.

I'd be interested to know what goes on regarding this.

I know it's normally controlled by the ecu, however I'd have thought that the ecu should be able to cope with higher than std boost in its normal state and adjust to suit. Of course a remap will modify the ignition/fueling more and optimise futher mind.[/quote']

it shouldnt be possible to run lower boost than stock. The Wastegate in our turbos have a 5psi spring, which is a bit lower than stock. The only possible way to run those 5psi is if you bypass the N75. The wastegate would see the pressure directly from the manifold and open as soon as 5psi is achieved. As far as Manual Boost Controllers go, i understand they kill the partial throttle in our cars. I havent tried any MBC, i use a EBC from Freedom design, designed exclusively for our DBW cars. It lets me crank the boost up to 14.5 psi while retaining the stock setup for 0 - 75% of the pedal travel. Once i pass 80%, it runs with the boost setting from the EBC.

Regarding the levels of boost our ecu is able to control, you can go as high as 15psi before the ecu enters limp mode. Also, after 15psi you start to run dangerously lean, so forcing the engine to run past that is looking for quick death.

honestly, i wouldnt run a MBC in my car because our cars are electronicaly controlled from the begining. I'm saving for a remap and an EBC from Apexi (AVC-R). It has everything i will ever want to control from my turbo, and together with a remap, i'll get complete control over the power levels of my car.

[Sheaf]

So basically, the N75 controls the boost via the ecu, which decides on the boost after reading various sensors, and depending on the map.

Thinking about it, I'm guessing the main problem is that the MAF sensor would pick up increased flow, when the ecu hadn't told it to run that boost, and therefore would kick up an error?

So the problem is not with the ability to obtain boost via a BCV it's more with sustaining it without the ecu getting confused and throwing a hissy fit.

Is the throttle controlled via the ecu also then, rather than a conventional throttle cable to the TB?

Also, you say it will run lean after 15psi... yet people seem to run over that with a remap. So, the std map is designed to run lean if the boost spikes? I suppose the 'limp' mode is basically a boost cut then. Even so, seems odd that they didn't map is to run rich just in case, most cars run rich top end for safetys sake.

Still dont understand how it's at all possible to run lower than std boost (yet higher than actuator) without disconnecting the N75 though, as this would keep the wastegate closed whatever an inline controller did. BTW, what is standard boost anyway?

I'm intrigued how it all works... I like to understand things like this

[bengie]

standard boost is about7psi

mine peaks at about 19psi@3500rpm ish then drops to about 15psi till the red line

[Sheaf]

Huh. So a remap does significantly increase boost then!

Does a remap alter the ignition or fuel or both, as well as the boost then?

[bengie]

both, ignition timing, fueling, boost levels all sorts.

my car was mapped with 97ron as its lowest grade fuel with the electronic boost controller set to high(if you get what i mean) and if i run it on 95 with this setting it pinks like mad and the ecu cuts the timing and boost way back.

[SkodiRS]

With the Jabba boost controller you essentially have 2 maps...max and min....the controller then allters all the parameters in between these.

My min boost setting gives 0.7 bar and a max of 1.35 bar.......this equate to approx. 280-340 bhp.

When the ambient temp is hot there is potential for boost not to be held and the car will feel very unresponse....turn the boost down to enable it to achieve a lower boost level and it will drive much better.

Can also be used to offset running with unleaded as opposed to super.

I normally run at the lowest setting...as it's more than enough for day to day running...but will also turn the wick up if I want to play.

[MaxLugo]

So basically' date=' the N75 controls the boost via the ecu, which decides on the boost after reading various sensors, and depending on the map.

Thinking about it, I'm guessing the main problem is that the MAF sensor would pick up increased flow, when the ecu hadn't told it to run that boost, and therefore would kick up an error?

So the problem is not with the ability to obtain boost via a BCV it's more with sustaining it without the ecu getting confused and throwing a hissy fit.

Is the throttle controlled via the ecu also then, rather than a conventional throttle cable to the TB?

Also, you say it will run lean after 15psi... yet people seem to run over that with a remap. So, the std map is designed to run lean if the boost spikes? I suppose the 'limp' mode is basically a boost cut then. Even so, seems odd that they didn't map is to run rich just in case, most cars run rich top end for safetys sake.

Still dont understand how it's at all possible to run lower than std boost (yet higher than actuator) without disconnecting the N75 though, as this would keep the wastegate closed whatever an inline controller did. BTW, what is standard boost anyway?

I'm intrigued how it all works... I like to understand things like this [/quote']

Yep, some (if not most) of our engines are Drive-By-Wire (ECU-controlled throttle). That is what gives us our smooth ,soft and lagless power delivery. The ECU reads the position of the pedal, and translates that information into a torque request for the engine, which then opens the TB accordingly.

Beyond 15psi you'll need a remap. I might be wrong, but i've never seen a stock engine spike higher than 11psi, so one might understand why VW didnt include maps beyond 15psi.

As bengie said, stock boost is 7psi.

It is good that you want to learn how this thing works, because with the 1.8t you'll have plenty of stuff to learn.

Question for SkodiRS:

Is the Jabba BC electronic or manual? Are you sure about those HP numbers? It's not possible to make more than approx 240hp with a K03s, and your numbers are more close to what a TT or LCR would make after an agressive remap and full bolt-ons. Anyway, 300hp is getting close to grenade levels for the 1.8t. Are you running uprated internals? Tell me tell me tell me

[Sheaf]

Right, so to sum up:

A boost control valve wont work because it's a completely ecu controlled affair, meaning if the boost is raised much above 7psi, then it'll basically run lean as it wont be expecting that much air, then sense a problem and go into limp mode.

However, on a remapped engine the ecu can cope with higher boost, and controls it via the N75. Yet, a BCV can be fitted in parallel with the N75, allowing the wastegate to open early, limiting the boost to standard, and basically having a adjustable power setting.

This can be done via an electronic boost controller for in car on the road adjustment.

This however will not affect the remapped fuelling and ignition settings, which should be better than standard.

So, how far can the remap go? How much can the engine take? And how come the ecu doesn't flip out again when the engine runs lower boost than the ecu tells the N75 to run?

I'd be quite interested to know how that 280bhp is achieved also.. is that with a K04, or something along the lines of a Garret GT28rs conversion?

[MaxLugo]

Right' date=' so to sum up:

A boost control valve wont work because it's a completely ecu controlled affair, meaning if the boost is raised much above 7psi, then it'll basically run lean as it wont be expecting that much air, then sense a problem and go into limp mode.

However, on a remapped engine the ecu can cope with higher boost, and controls it via the N75. Yet, a BCV can be fitted in parallel with the N75, allowing the wastegate to open early, limiting the boost to standard, and basically having a adjustable power setting.

This can be done via an electronic boost controller for in car on the road adjustment.

This however will not affect the remapped fuelling and ignition settings, which should be better than standard.

So, how far can the remap go? How much can the engine take? And how come the ecu doesn't flip out again when the engine runs lower boost than the ecu tells the N75 to run?

I'd be quite interested to know how that 280bhp is achieved also.. is that with a K04, or something along the lines of a Garret GT28rs conversion?[/quote']

Well, i dont know if a MBC will work on a stock ECU, because even if you bypass the n75 and run a direct mbc, the ecu has several ways to reduce the intake pressure. You still have the n249, that will activate the dv to dump excess boost, and the ecu can even close the TB (dbw only) to "save" the engine. I believe you can run 14.5 psi without problems (that's what i run with my EBC). After that, i'm not willing to try without a remap.

I've never heard about running a mbc in parallel. If you want to control boost, i *think* you have to eliminate the n75 (leaving it just plugged to the electrical line) and run with just the mbc. ( as you can see, mbc's and me dont get along very well).

1.8t in general can take 300hp reliably if you dont punish it too much. A remap on a k03s will take you to 210-220hp, and you can achieve 240hp if you add all the bolt-ons in the world and a little luck.

For those 280hp that SkodiRS claims , i would guess he's runing a fully tuned k04 engine, or an aftermarket turbo like the GT2871R (which should get him way beyond 280hp).

[SkodiRS]

Question for SkodiRS:

Is the Jabba BC electronic or manual? Are you sure about those HP numbers? It's not possible to make more than approx 240hp with a K03s' date=' and your numbers are more close to what a TT or LCR would make after an agressive remap and full bolt-ons. Anyway, 300hp is getting close to grenade levels for the 1.8t. Are you running uprated internals? Tell me tell me tell me [/quote']

Oh yes...the figures are real....not running a KO3S though....IHI VF34 and sundries (FMIC etc). Running standard internals and clutch...max boost map has been tailored to take this into consideration. Runs very well indeed....no clutch slip.....although it is pretty hairy in the wet.

Max power isn't so much of an issue...it's the torque that will cause the problems....hence why my max boost torque figures aren't a good as they possibly could be.

Uprated clutch on the to do list...but no point in changing it when it's not required.

[Sheaf]

Gotcha.

I think I've got it all sussed now.

Yeah, a GT2871R should go well over 280bhp, lol, they're rated to about 400bhp or so I think! By the sounds of it the K04 is the most logical upgrade, then a remap to suit.

[bengie]

not sure there is a lot of point in doing the K04 route myself, you'll need to uprate/change injectors, manifold, boost pipes, map etc etc to get it to work. you might aswell change the parts needed to fit the garret/ihi turbo and give yourself much greater potential