TOPIC: 1999 Buick Riviera 3.8L S/C BC Canada First Mod

Harry here from Kelowna BC. I,m about to do my first mod to my 99 Buick Riviera. The engine is Supercharged 3.8 L. If anyone has done a mod to this engine with the supercharger are there any tips that I should know about in advance. How well will this mod work if the supercharger is boosting the intake air pressure to pack air into the cylinders. any tips would be welcome.
Cheers
Hary

Hello Harry,

I know there have been a number of vehicles done that had turbo's on them and they found it to smooth out the transition of the turbo kicking in.

I'm presuming the S/C doesn't kick in during normal motoring around.

As far as the 'normal' conditioning of an engine to get the desired effects we look for a higher than normal manifold vacuum, from 18-19 inches of vacuum to 20-21 inches.
This usually involves relocating the PCV hose from the intake manifold to a point ahead of the throttlebody and capping the port on the intake manifold. If there is an Idle Air Control we restrict the pathway to reduce the amount of available air that passes through it.

What type of throttlebody do you have on the engine (TB, TBI or Carb) and is it cabled or fly-by-wire?

You will let us know, Post pictures, would love to see the setup.

and... Welcome aboard

Karl Fortner
Tacoma, Washington

These engines actually are undergoing investigation by myself here in Hamilton, MT.

I did one of these for a local customer. Original mpg was 29. His first tank resulted in a count of 66 mpg's. Second tank, it dropped to 26 where it stayed for two tanks, then jumped to 44.

So, be sure to let the man know the mileage could be all over the map, but the performance and emissions will be nothing short of REMARKABLE!

When you get the TB off, you should have already looked at the video on GroovyServiBulletins that covers the 3800 series.

You were a Boy Scout, right? What's their motto?

BE PREPARED!

I have now done the groove and I discovered that there is no PCV system on this engine. There is a vacuum port a few inches from the throttle body for the brake booster and a vacuum valve to activate the supercharger but that is it. I assume, strictly from observation, that the engine vacuum causes a bypass of the supercharger and that it would gradually engage as the throttle is depressed causing a decrease in vacuum It is a TB injection system with a throttle cable. I also found out that the groove drilled right through the TB housing in two places. I took some pictures and I will post them as soon as I can figure out how to do it. Now I must find a material to use to fill in the holes made by the groove. This supercharger would in all likelyhood be the same one GM used on Pontiacs Cheveys and Oldsmobiles with the same 3800 engine.