Summer 2016: Exciting times are ahead for Abarth Racing UK, who have been working hard in conjunction with Turbo Technics to produce a game-changing turbocharger product line and service. TT have been specialising in the manufacture of turbochargers and specialist machinery used in turbocharger repair for over 35 years, and the combination of their expertise with that of ARUK’s Head Engineer Andy Dawson promises groundbreaking results. Over to Andy for the story so far…
The big Turbo kit is coming! We are currently finalising the kit and optimising the turbo.
When I first became involved with the Abarth 500 I was told by Italy that the power limits were governed by the turbos and the pistons. I was told that the standard IHI VL38 would only pass enough air for 163bhp and the Garrett 1446 choked at about 200bhp. I asked about more boost and was told that the top land on the pistons collapses and traps the top ring.
I became somewhat confused when many tuners began quoting big power outputs.
Earlier this year I sold a car to New Zealand and the new owner wanted more than the standard 190bhp that the AC has, so I made some phone calls. The tuners that were advertising 240bhp began to shy away when I asked probing questions. One company told me, “Yeah, 240 is easily possible, we can get over 200 with the IHI turbo.” Needless to say, I was unconvinced!
I started to talk to racing driver Marten Bonner, one of the few people using an Abarth 500 for competition. At the time, he had a Garrett 1446 fitted and had spent a fortune on mapping for the SLS series at Knockhill race circuit. Marten had the power checked for the series and found that he only had 150 despite his mapper telling him that he had 240. The first time he used increased boost the shaft in the turbo snapped and the turbine wheel made a bid for freedom down the exhaust pipe. I took Marten a replacement turbo and an ECU with our standard 190bhp mapping – bingo, he went 3 seconds a lap faster than he had gone before.
We wound the boost up and the second 1446 also snapped the shaft so I went and spoke to my old friends at Turbo Technics. TT's Geoff Kershaw looked at the exhaust turbine and said “not big enough” so Pete and the lads built us a hybrid turbo with more flow. It wasn’t a direct replacement but effectively we just needed a new downpipe.
Marten had fitted an aftermarket front mount intercooler, so at the same time as fitting the bigger turbo we fitted one with a lot more flow capacity.
As soon as we drove the car we knew that it was a different animal. After a remap, we have 1.6 bar of boost from 3000 to the red line with a maximum power of 242bhp at 5500 with a completely standard engine other than one of our flywheels and clutch. Since then we have improved the mapping and have 275bhp which is on the limit for the injectors and fuel pump.
We will be able to supply a kit in the near future; we’ve experimented with using the TT hybrid on a Multiair as per the American cars, the later Puntos and the Alfa Mito. We saw a gain of 30bhp and now need to do a remap to move forward on that. For a base A500 the kit will have to include the 2.5 bar boost and MAP sensors, bigger injectors and longer oil feed and drain pipes.