Top End Power On A Gti.

[lahondal 17]

Hola.

 

I have a rallye GTI on twin 40s dellorto and megajolt, it haves a very good torque at low RPMs, since 2500 to 5000 RPM its pull hard, but 5000 RPM onwards, it feels heavy and only "makes noise"...

 

I have 32mm venturis, i know there are small for a 1.9, but are small enough not to produce power at high revs? Or maybe can be a jetting problem?

 

The engine its stock except carbs, exhaust manifold and lightened flywheel...

 

At what revs begins the GTIs to pull?

 

Un saludo.

[j_turnell 137 3 Cars]

Ideally you need it setting up on a rolling road with a wideband lambda. Sounds like its running lean up top.

[matyasg 0]

Ideally you need it setting up on a rolling road with a wideband lambda. Sounds like its running lean up top.

Or too rich. You need a wideband definitely to decide it.

[lahondal 17]

Can be the ignition advance?, i set the advance at 37º at 4500 RPM max on full throttle. I load a advance map of a 1.6 GTI which came with the megajolt, but the max advance was 40º on full, i thought..."this is too much", so i reduce advance by 3º.

 

I searched in the forum and, the maximum advance at full throttle is 31º at 5000 RPM for a XU9JA block, its correct?

 

I need to create a new full ignition map...

 

Un saludo.

[j_turnell 137 3 Cars]

It needs to go on the rolling road and be mapped.