I bought these on a whim:
People said, what's the point of doing that on stock cams - it will make no extra power.
I was also told time and time again that aftermarket management such as Emerald or DTA was the only way to go and that it "wouldn't work right on stock management".
Ever the tight Yorkshireman, and wanting to again do something "different to the norm" as I did with my old DTurbo - I decided to call on the help of the Chip Wizard, up here in Rochdale. Wayne Schofield has an excellent reputation with all things Peugeot, so I thought if anyone could do it - he could...
So, I headed over to Wayne's unit with the car now totally stock, other than a K&N apollo air filter and Longlife systems 2.5" stainless exhaust with sports cat and lightly advanced inlet cam.
We ran the car up like this, seeing a healthy 177hp. About right given the tame breathing mods and advanced inlet cam timing.
After a couple of Jaffa Cakes it was time to whip the standard inlet off. Easy job, loads of you have done it - needing nothing more than some basic tools and a new gasket for refitting (if you do!)
With the manifold off, the fuel lines needed modifying to suit the Jenvey throttle bodies - really just a case of cutting them down and using some bits of Porsche fuel pipe lying around in the workshop.
Once we'd done this, we cut off a few tabs of metal on the Jenvey bodies to give us good clearance for things like the dipstick and throttle linkage:
Last but not least was modifying the throttle cable to fit the Jenvey set up, easily done by a bit of cutting and trimming:
Once fitted, plumbed in and bolted up it was time to test fire the car, on the stock mapping... suffice to say it ran like crap, coughing and spluttering - not surprising given half of the connectors it was expecting to see weren't plugged in!!!
Despite that - the car still managed 194hp even with all the pops and bangs!
This graph really shows us where even on stock mapping and running like crap, the Jenveys help us to gain, also quite surprising was the fact we didn't lose TOO much torque low down - which was a bit of a concern:
So, now to the mapping... It was getting late on into the evening now - and with a mammoth live mapping (running the car directly from the laptop) session ahead of us... we cracked open the ECU and tucket into some biscuits:
Wayne started reading the file - and tried to explain to me and Chris (Brynllwynog2) how the ECU referenced different values, loads, RPMs etc...
We hooked the car up to an emulator box, essentially allowing Wayne to run the car directly from his laptop in the car, and optimise the mapping on the go whilst simulating different load and RPM conditions on the dyno and watching the feedback from the wideband lambda hooked up to the exhaust:
Next came the huge, job of mapping.
This was no "let's map it for headline power figures" exercise. Wayne spent literally 6 hours optimising every single load and RPM site in the ECU, ensuring that the fuelling was spot on across the board for the new found airflow provided by the Jenvey bodies.
Only when he was happy all of the part throttle, full throttle and transient fuelling was absolutely spot on did he begin the power runs. The first couple of runs showed 197, 198 and 199hp - so tantilisingly close to the magic 200hp. Thankfully, Wayne said "there's a bit more to come out of this yet, hang on..."
With a few more tweaks on the laptop and the timing and fuelling optimised to their full, we saw 204.9 bhp and 170.3 lb/ft
The final graph shows the first run, with the stock intake and mapping and only basic mods giving 177.8 bhp and 151 lbft, and then back to back runs of the stock mapping with Jenveys, giving 194.7 bhp and an erroneous torque reading unfortunately (spike when dipping the clutch on the dyno) and the final map with Jenveys giving 204.9 bhp and 170 lb/ft.
All in all with the stock power figures being 167 bhp and 145 lbft of torque we can see that light breathing mods and some modest cam timing changes can yield us a 10 bhp and 6 lb/ft gain, with Jenveys giving a whopping 38 bhp and 25 lb/ft gain over stock.
I have to say a personal thankyou to Wayne at Chip Wizard for putting in so much time, care and attention to detail on this and I would urge any of you to use him as your tuner... he REALLY knows his stuff, petrol or diesel.
The car pulls cleanly and strongly through all the gears and drives, dare I say it, better than a stock one. Certainly smoother and with far better throttle response. As they say, it's "how it should have left the factory!!"
Hopefully this will allow a few more GTi-6 owners to go down the throttle body route, without the need for full blown aftermarket management systems!!!
Let's see what happens when we throw some cams into the mix.....
Cheers for reading,
JP
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HDI Engine Tuning / Remapping Services - https://www.facebook.com/dervtech306 GTi-6 Track Car - 200+ hp all N/A!
306 DTurbo Track beasty - 209.9hp - RIP