Moderator

Here are some rough & ready before & after tuning figures for some common VW 8V motors

First the original figures for the 1,8 liter motors

1800 motors
GU – – 1.8 — 90 bhp @ 5200 & 145nm @ 3300 – comp ratio -10.0 to 1 – n/a – no cat
GX – – 1.8 — 90 bhp @ 5250 & 137nm @3000 – comp ratio — 9.0 to 1 k/j – with cat
1P – – 1.8 — 98 bhp @ 5400 & 143nm @3000 – comp ratio – 10.0 to 1 d/f – with cat
PF – 1.8 – 107 bhp @ 5400 & 157nm @ 3800 – comp ratio – 10.0 to 1 – d/f – with cat
PB – 1.8 – 112 bhp @ 5400 & 159nm @ 3800 – comp ratio – 10.0 to 1 – d/f – no cat
PG — 1.8 – 160 bhp @ 5800 & 225nm @ 3800 – comp ratio – – 8.0 to 1 – d/f – with cat

2 liter
ABA – 2.0 – 115 bhp @ 5400 & 166nm @ 3200 – comp ratio – 9.0 to 1 – d/f – with cat (America only)
2E — – 2.0 – 115 bhp @ 5400 & 166nm @ 3200 – comp ratio 10.4 to 1 – d/f – with cat (Europe only)

Tuning the common Syncro motors

GU. 90 bhp
1) Swap the Pierberg carb for a 32/34 or 34/34 DMTL or DMTR Weber – — + – 5bhp
2) Swap the head for the PF, PB or PG head, this has bigger inlet valves – + – 5 bhp
3) Swap the camshaft for a fast road cam say 268/270 degrees ish – – – – – + – 5 bhp
total increase 15 bhp = 105 bhp ish
Remarks, this motor has an identical bottom end as the PB motor

GX 90 bhp
1) Forget it! apart from the cam + – 5 bhp

1P 98 bhp
1) Swap the ECU for one from a PB motor + 14 bhp
2) Chip tune the PB ECU — – – – – – – – – – – – + 10 bhp
3) Decat the exhaust, fit the GU front box + – 5 bhp
4) Swap the camshaft as above – – – – – – – + – 5 bhp
total increase 34 bhp = 130 bhp ish
Remarks, apart from the ECU & cat this is an identical motor the PB

2 liter

ABA this is America only so we over here are not likely to see many of them, however it does have a rather nice crossflow head, but its fitted with a very soft (emission) cam which wants throwing away

2E 115 bhp

1) Chip tune the ECU – – – – – – + 10 bhp
2) Fit ABA crossflow head – – + 15 bhp – remember to replace the ABA cam with euro vw cam
3) Swap cam for a 268/270 degree one, as above – – – – + 5 bhp
total increase 30 bhp = 145 bhp
4) Modify exhaust system – – – + 5 bhp and you should see a nice 150 bhp with lots of torque.

The main problem with tuning the right hand drive Golf 2 Syncro is the single exhaust downpipe, its rubbish, but to fit anything decent like the lhd twin downpipe assy involves a lot of work cutting out a piece of the transmission tunnel to allow clearance and then cutting and rewelding the pipe as well, it is a lot of work but it does allow the engine to breath far more freely, and while this may not give a big power increase on its own it does mean that you get the full effect of any other mods you may have made.