Have you got the car back ?
Short story...not yet!
The Arma kit uses solenoids, axle speed sensor and a piggy back ECU to control boost and fueling. It is a clever but fairly elaborate design that I was worried could cause headaches in the future. I didn't want additional electrics under the chassis and in the engine bay where the chances of non OEM parts (of unknown quality) failing were high. The brief for Regal was to adapt the Arma kit to run like the VF kit they had fit to the Z4 i.e. larger injectors, recirc valve and running with OEM sensors.
I was told the car was ready last Monday so went down to pick the car up, took a day off work, got the train down (4 hours one way!), paid for Regals work and took it up to SSR to get a run on Charlie's dyno. Chris, the MD had told me the tune was 95% there and to get the final 5% could take months of fine tuning. From what he said the only slight glitch in the tune was that the idle fluctuated which he showed me before I paid. However, when I left to drive from Southampton to Farnborough for the RR session I found that the throttle response from 1,000 to 3,000rpm was jerky and hesitant a lot of the time. Charlie confirmed in scenarios that caused this to happen the AFR wasn't right. I therefore drove the car back to Regal and left it with them and got the train home!! I left the house at 6:40 and got home at 20:40, a very long day and cost me £100 in train fares!
Regal are currently making some hardware changes to the set up (which I had asked them to do from the start!). The most important one is to run a Forge recirculation valve rather than the atmospheric blow off valve that came in the kit. I am assuming as the MAF is connected in the intake it must have been used in the Regal ECU tune, I am not sure how this would work with an atmospheric blow off valve, unless running an Alpha N tune??! Hopefully not running the recirc is why the idle was bad and the part throttle felt horrible!! We shall see.
I am not really sure what Regal are playing at. Even Charlie at SRR was surprised as he thought Regal had a good reputation. I am hoping they have lots of other work on which is why my car hasn't had the attention it should have had. I am amazed that they would let a customer take a car when the work so blatantly wasn't really ready. The MD seemed completely unphased when I dropped the car back. He had excuses and tried to convince me to take it home to put a few more miles on it and see if I 'could drive around the problem'. On reflection things said by email and when I picked the car up hinted at this. At present I am just going with the flow and hoping they pull their finger out! I am sending chaser emails every few days now though!
The mechanic working on the car has SC'd his own N52 in a 3 series and they have SC'd the N52 Z4, both of these installs used a Vortech blower and not a Rotrex blower (one of the excuses as to why my car wasn't running 100%). I am therefore confident that they have the knowledge and experience but just need them to focus!!
On the upside, the drive I had did show that from 3,500rpm up you could really feel the extra power! The car really pulled hard as the revs rose but felt pretty standard in power under 2,000rpm. The car on Regals dyno did a base run of 267bhp and 250lbft, the final run was 389bhp and 330lbft, however, with heat soak after 5 mins on the dyno they saw this dropping to 380bhp.
Fingers crossed it should all be sorted out in the next few weeks. From previous experience with custom work on cars I have become very patient!! It has been nearly 11 weeks a car and I haven't showed my annoyance to Regal yet!! I just want them to get on with the job properly.