Alfa Romeo 147 GTA project

[Alfatango]

1 hour to replace a strut? Quickest gun in the west .

[warsch]

It's actually 30 minutes per strut, so 2 hours all up

[warsch]

Ok, so the project turns to take longer than expected.

I went to check why it misfires, thinking that timing was off. But sadly discovered that intake cams are noticeably worn.



Also there are some sludge deposits, so it seems like one of the previous owners was not changing oil on time.

[warsch]

Also, I'm now really curious what the GTA camshaft specs are. 2.5, 3.0, 3.2 and C&B and any really.

I've sourced some used cams and will be ordering custom ones, so need to figure out how to spec them

[Alfatango]

Should be a bit of monster once its on the track.

[warsch]

When and if that happens.

I'm still a bit cautious as something caused the cams to wear down. But I've found an economical way to get the cams, so will give it crack.

So, for the reference, here's some info on busso cams

3.0 V6
Cam Lift Duration Open Close Lobe Center
Inlet 9.3mm 215 1 BTDC 32 ABDC 109
Exhaust 9.3mm 215 37 BBDC 2 ATDC 109

3.2 V6 GTA
Inlet 9.3mm 223 1 ATDC 44 ABDC 113
Exhaust camshaft's timing's shift is negligible (1 degree).

??GTA inlet has 9,7mm lift with 246degree duration and 3,0 V6 has 9,3mm lift with 236 degree duration.





FAST ROAD MEDIUM
Inlet cam lift: 9.2 mm - Exhaust cam lift 9.4 mm
Duration 274°/272°
Valve Timing Inlet 25° - 69° / - Exhaust 59° - 19°
Valve lift Top Dead Centre (TDC) Inlet cam 1.3 / Exhaust cam / 0.7

FAST ROAD UPPER MEDIUM
Inlet cam lift: 9.9 mm - Exhaust cam lift 9.4 mm
Duration 268°/272°
Valve Timing Inlet 22° - 66° / - Exhaust 59° - 19°
Valve lift Top Dead Centre (TDC) Inlet cam 1.4 / Exhaust cam / 0.7

FAST ROAD MAX
Inlet cam lift: 10.4 mm - Exhaust cam lift 9.2 mm
Duration 260°/274°
Valve Timing Inlet 20° - 60° / - Exhaust 67° - 27°
Valve lift Top Dead Centre (TDC) Inlet cam 1.2 / Exhaust cam / 1.7

RACE MEDIUM
Inlet cam lift: 11.4 mm - Exhaust cam lift 11.2 mm
Duration 300°/280°
Valve Timing Inlet 45° - 75° / - Exhaust 70° - 30°
Valve lift Top Dead Centre (TDC) Inlet cam 4.0 / Exhaust cam / 2.8
Clearance 0.40 / 0.30
To fit these camshafts it will be required to change from the standard hydraulic cam followers to mechanical cam followers.

[Paul Gulliver]

"I'm still a bit cautious as something caused the cams to wear down"
Usual cause is using the incorrect oil. Use what Alfa Romeo recommend as these oils usually have a higher zinc content which helps reduce wear.

[warsch]

I really hope that's the case. That someone didn't use the right oil and/or didn't change it on time. As I can eliminate this problem easily. I run my Alfas on Penrite Premium 10w-60, which has proven itself on a racetrack in my and other cars.

I surely will also flush the oil couple of times prior to racing it.