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Discussion Starter · #1 ·
To cut a long story short, I had a MAF problem and at the same time wanted a tuning box for my car. Someone suggested the other day that a change to a 130PD Boost Control Valve and MAF may help as a base for more power when tuning.

Well.... (please note - tuning box remained fitted throughout this)

Changed the N75 before the faulty MAF and that seemed to smooth out the hesitation a little. Then changed the MAF, well TBH it felt flat after the change so I took the car back to where I stay and disconnected the battery for 1/2 hr.
(Strangely enough the MAF is almost identical with many of the same part numbers stamped in it - except one - and it's listed as a different part/price from the 115 version)

Re-connected and took it for a spin, good progressive power, very smooth and less of a surge at 1700-1800rpm than before so much easier to drive. Better breathing too as it didn't run out of steam at all, reved happily to the red line.

Just as a comparison I put the 115 N75 back on and did the same circuit - big surge of boost and then tailed off, seemed as fast but not as smooth so swopped back to the 130 N75.

Objectively: I don't know if this change would make a difference to a std car. From what I felt through the seat of pants test I think the original suggestion is spot on - I think these changes followed by a proper re-map would give more power than a std 115 with map. The parts come to just over ?100, so if you're spending ?500 on REVO it may be just the thing to get an extra 10-15bhp with a good RR and laptop 'driver'.

Part numbers are for the 130 PD - ASZ engine:
MAF - 071 906 461 AX (the X denotes exchange part)
Boost control Valve - 1J0 906 627 B

I hope this is useful if you're planning to tune your 115PD - I found it's improved the driveability and as I'm an old fa*t I enjoy it that way! Please, don't do it to a std car and expect immense grunt, it's a subtle change and best doen as part of a wider spread of mods.
 

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I'm pleased this has made a difference. Out of interest are the part numbers you listed for both the ASZ & ARL(150) or just the ASZ?
 

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Interesting reading there Richard. I'm getting mine Upsoluted next weekend and i'm using a Merc Maf atm, I will need to get a VW maf so may have to go for the 130PD one, and may aswell go for the N75 valve too.

Lets hope I see the same results[;)]

Lee
 

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Discussion Starter · #5 ·
It has DC, thanks for the guidance!

I think they're just the ASZ - I checked with another dealer before actually ordering.

Lee, the N75 is an easy swop, you'll need some longer vacuum hose as the fittings face the opposite way to the 115 version. Let me know how you get on!

DieselPower - what else have you done? that's a good power figure.
 

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Thats a nice setup you got there[8D]

Richard: Seeing as when I get Upsoluted the BHP goes upto 145-150, do you think a MAF from the 150PD would benefit more than the 130PD MAF[?]

May give Simon Coe a ring to see what he thinks.
 

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Discussion Starter · #11 ·
I don't know Lee, I went for the 130 parts because the turbo and intercooler are the same so should be compatible with the rest of the engine/ECU for when I take the tuning box off.

Simon may know, or give Star performance a shout - they've done a 115 with these bits swapped and saw over 160bhp I heard.
 

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Good point, didn't think about that[:I]

I will give my local stealers a ring in a bit too see if they have the bits in. How much did the MAF cost, did you exchange your old MAF and get a discount on the new one??

Cheers
 

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Discussion Starter · #13 ·
I got the boost control valve from the classified here, the MAF i simply explained my predicament to a very helpful parts chap in Lawtons Macclesfield who siad they only look at the part number on the outside of the tube so I swapped my 115 MAF back into the tube and he's done the exchange deal. The 130 MAF is slightly more than the 115 and is listed at ?75.10 +VAT. Ask for a bit off discount I usually do and get 10%.
 

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Ordered the parts today, the dealers had the MAF but not the N75 valve so I will be picking them up tommorow.

I'm getting Upsoluted on Saturday too so I will let you know the results, if I get time during the week I may try fitting them to see if it makes any difference to the standard engine.

Cheers

Lee
 

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Discussion Starter · #15 ·
Try it in phases - MAF first, then boost valve and see what happens - I'd be interested to know what you think?
 

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Had a day off work today, so fitted up the new parts.

First I changed Merc MAF for the 130PD MAF, disconnected the battery for half an hour, then took her out for a test.

TBH it felt pretty much the same as the Merc MAF, responsive with a big surge of power around 1700-1800rpm all the way round to 4000rpm.

Then I fitted the N75 valve and took her out again.

Its exactly like you described Richard, very smooth delivery of power with alot less surge.

Its alot better to drive.

TBH I don't think my car has felt this good in the 3 years i've owned it.
 

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Today i tried newly purchased 130 n75 valve and it made no difference at all compared with 115 n75. also tried with merc and standard maf combinations with no difference whatsoever.

all in all i spent 4 hours chopping and changing [V]

Im sure the dealership will not refund the money so i will have to put on classifieds. ?32 spent on snake oil [}:)]
 

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Discussion Starter · #18 ·
Lee, glad you've enjoyed it!

Bob, sorry you feel that way.

You'll only get the full benefit if you put the 130 MAF in too. I did say in my original post the changes are very subtle, you're not getting another 30bhp remember.
 

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The part numbers for the 115 maf and 130 maf are the same from VW [?] (it is the bit the maf goes into that is bigger on the 130)

Subtle for me was no difference at all [:eek:)]

Snake oil [B)]
 

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Richard, this makes for a very interesting read. I recently had my 115 tuned by Simon Coe @ Upsolute and although the car is much more rewarding to drive with bags more torque and bhp it can feel jerky around that 17-1800 rpm.

I have been looking for a way to try to smooth this out and your solution with the new MAF and boost contol valve may just be the way. After I have blown all my money on beer and car parts at Inters, I will put my sensible hat back on and look into getting these parts.

Just out of interest, has yours been remapped or is it a tuning box? And why does the battery have to be disconnected for 30mins, does this reset something?!

Thanks for the advice [:)]
 
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