How to mod your NA “naturally aspirated” L36/L26
The first mod is usually our ZZP 1.0 PCM file. It will adjust many things to improve the cars performance and should not have any effect on fuel economy or emissions.
The next thing would be a cold air intake. We have 2 options: ZZP Cold Air Intake, and of course a “drop in” K&N Air Filter that would install in your stock air box. We do not recommend running a K&N drop in filter in a ’98 or older air box because that intake does not flow very well. On the 1997/1998 cars, you will also need the 99+ Coolant Bottle because of the factory coolant bottle location.
The next recommendation is just to help resist KR or “Knock Retard” NGK TR55 Spark Plugs (in Copper and Iridium) and a 180° Thermostat. If you replace the thermostat we highly recommend replacing the Thermostat Gasket at the same time. We also offer a couple options for spark plug wires. We have our ZZP 10.5mm Spark Plug Wires and we offer the stock ACDelco Spark Plug Wire replacements. We do also offer ZZP 3800 High Voltage Coil Packs for those that would like to upgrade the stock ones.
Now onto exhaust, the stock catback will support up to around 300whp, so we recommend replacing the stock downpipe with our ZZP Downpipe. We recommend a 2.5” version for NA (naturally aspirated, not supercharged) application to avoid losing low RPM torque. You can sometimes reuse your factory gaskets if you use Copper RTV to reseal them, however we do offer the front and rear replacement gaskets, they are called 2.5” Downpipe Gasket, and the 3800 Stock Manifold Gasket.
Here are a couple very unique and cool electric upgrades: Alternator Voltage Booster, Alternator Power Cable, and Fuel Pump Rewire Kit. They will improve the cars electrical system. Brighter headlights, better stereo performance, improve the fuel system, etc.
We also offer a ported High Velocity Throttle Body however it is only available for the Series II cars. The series III car has a rather large factory throttle body already. (No, sorry it is not interchangeable with a series II car)
Our HV3 High Velocity Insert is a GREAT upgrade, a must have in our opinion, it will give you about 9hp at 5600rpm but near 30hp at 6000rpm where our 1.0 pcm shift point is set. It replaces the factory runner insert with a high velocity insert that shortens the runners a ton. There aren’t really any noticeable side effects of this mod.
We always recommend keeping a fresh High Flow Fuel Filter in the car.
The next step will require opening up the engine a little bit. There are two options, we offer 1.9 rockers, (+10 hp at the crank) which are lightweight rocker arms that increase the lift of the cam by bringing the rocker ratio from 1.6 to 1.9. Or the 2nd option our GT1 camshaft which will give you around 30 hp. However to get its full gains, you would also want to install new lifters, valve springs and retainers. The cheapest option is the 90# Valve Springs and Comp Valve Spring Retainers along with LS7 Lifters. It isn’t a bad idea to install a Rollmaster Double Timing Chain, Machined Oil Pump Cover, and Extra Thick Front Cover Gasket. That will give you a new timing chain and disable the balance shaft.
For those that would like to make a lot more power, we do offer a supercharger and turbo kit for the NA 3800. The supercharger kit is called the L36 Supercharger Kit, and we also have 2 different turbo kits based on your overall horsepower goal, the z3, and the Stattama Turbo Kit.
There are more mods for sure, but this is a great starting point.
This is also ONLY a power writeup, if you want to improve your cars handling, please email us and we can help with that as well.