The pretty much the same, a few slight changes as the years went on with anti stall devices, air shroud fuel injectors, bigger fuel filters, different oil coolers (older engines are air cooled, later cars are water cooled) Can’t think of anything just yet but basic stuff the same.
If you can get the eairly exhaust manifold, the type with 6 studs holding the down pipe on as much better design than the toilet bowl type with big C clips holding the down pipe on.
I believe the inlet manifold is the same.
Have a look at GTXRA Gti for pics of engine bay etc.viewtopic.php?f=19&t=21099
Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
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