Stage 2 Upgrades

This stage of upgrades requires more technical skill and not considered "Bolt-ons". There are various levels for each type of upgrade in this section. The selection of the level will depend on your goal and purpose for your car. Also when selecting upgrades its a good idea to check any racing rules if you plan on racing. You don't want to perform upgrades that will disqualify you.

 

 

Head porting

Stage 1, Stage 2, Stage 3 - these are the terms you hear when talking with companies that provide porting and polishing services. How do you pick? What do these terms mean? Generally they relate to the intended application. Street, hot street/light race, full race respectively. ...

 

Cam upgrade

There are many cam choices - their are questions to answer when making the choices. Cost, performance, drive ability. The cam specs pertain to the 8 valve solid lifter motor.

Modest cam upgrade

Cams in this section are less expensive, don't effect the idle quality, have a slightly better power curve than the stock cam. Expect upto 4 - 5 HP increase. 1.6 Liter cam from 1979 or earlier 8 valve VW Rabbit - is an upgrade over the Stock 83/84 Rabbit GTI ,Scirocco cam called the c grind cam. Expect upto 4 - 5 HP increase.
G grind cam - The Euro Golf I GTI cam, a better upgrade cam. Expect up to 4 - 9 HP increase. This cam is available from performance after market vendors such as Techtonics Tuning, and Autotech.  Works well with standard compression ratios.  When evaluating other cam options look for cams with advertised duration less than 270 degrees with the stock compression of 8.5:1

Moderate cam upgrade

Cams in this section are more expensive, may effect the idle quality, better power curve than the stock cam. Important to pay attention to the vendor specifications when selecting these cams, Heavy Duty valve springs are often required, and at times cam lobe clearance needs to be checked. Expect up to 12 HP increase. Don't expect to reach the 12HP gain with an otherwise stock setup. Often Stage I port and polish head work and intake manifold is required to get the most benefit. Advertised duration of 270 - 280 degrees is the max in this category.  Compression ratio's around 10:1 -11:1 are generally needed. 
These cams are available from performance after market vendors such as Techtonics Tuning, and Autotech, Kent Cams, Web cams.

Elaborate cam upgrade

Cams in this section are most expensive, do effect idle quality(often will not idle properly at 1,000 rpms), do require Heavy Duty valve springs, and more often than not cam lobe clearance needs to be increased. These are almost exclusively for Racing applications. Expect more than 12 HP increase. Don't expect to reach the 12HP gain with an otherwise stock setup. Often Stage I port and polish is required. Advertised duration of 288 degrees is the beginning in this category. With lift ranging from .42" to .55"  Compression ratios higher than 11:1 CR required.
These cams are available from performance after market vendors such as Techtonics Tuning, and Autotech, Kent Cams, Web cams.

Headers

Headers replace the exhaust manifold and down pipe with a high flow replacement. When selecting a header the manufacture specifications how and where the power band shifts is important to identify. Normally headers designs make a trade-off between low end torque for high end horse power. Headers are not just for Racing though.
There are two primary header designs.

The Tri-Y, which preserves more low end torque and not as high peek horse power. The tri-Y design gets is name from having 3 pipe merge sections. 

The 4 into 1 design has 4 longer primary pipes that merge into 1 collector. The 4 into 1 design favors peek top horse power over low rpm torque.
Expect more than 10 HP increase.
Headers are available from performance after market vendors such as Techtonics Tuning, and Autotech, Brospeed.

Intake and exhaust systems - How are they are used to make horsepower, selecting the right exhaust "system".

TODO

Ceramic coating --