The Alfa Romeo 156 is a stunning looking car, be it The original version designed by Walter De Silva, or the facelifted design as in this case, styled by Giugiaro. When it was released in 1997 Frankfurt Motor Show it was a sensation and went on to win the 1998 European Car of the Year award. The 156 became the 3rd best selling Alfa Romeo of all time, behind the 33 and the seminal Alfasud.
The facelifted 156 brought a classic front end design that was continued in the later 159. Along with the facelift to the body shell, the 2.0 Twinspark was updated to become the 2.0 JTS (Jet Thrust Stoichiometric). This boosted torque from 138 lb⋅ft to 152 lb⋅ft and HP from 155HP to 165HP. This engine also featured in the shapely GT.
Unfortunately direct injection engines have a significant downside, because fuel is not injected into the intake port, carbon builds up in this area slowly strangling the engine’s performance.
This JTS engine had covered 130000 miles and was one of the most clogged up we’ve seen. Airflow readings suggested it was making around 120HP, in reality it felt like 100HP on the road.
It wasn’t until we started the carbon cleaning with walnut shells, that we realise just how much carbon was in the port.
Doing this job was a bit like pushing mud uphill and took a good 6 hours of work to get rid of the build up. Not to mention many hours to remove and refit the manifold which involves loosening an engine mount to get clearance.
The proof of any carbon clean is in the driving. We checked the Air Flow and it’s now moving 16.9 lb of air in a minute. You may wonder why lb min? Seems old fashioned? Well on pump fuel lb min is very useful as all you need to do it stick a zero on the end to estimate HP. So it seems that we’ve got all the original Ponies back in the stable. This car now feels genuinely rapid, albeit the gears are still long for emissions reasons, but it’s put the pep back and it fizzes like an Alfa should.