40th Stillen Supercharger Build

Originally Posted by Nut_N_Much

Topical areas to look for with this kit is under the manifold. If your doing the smoke check start at the intake filters, before SC. That will show you leaks in the SC boot were BOV ties in. Second pull vent line off intake tube and smoke it out. That will show leaks in the TB's, Vacuum Lines and under the manifold.

My Boost showed 11 psi then dropped after a few days, my issue was getting the manifold tighten with equal pressure on all the bolts. One to tight or loose will create a leak. Flaw in design of intake, no access to do it right.

Check with tuner: If he can't get 3 runs with solid numbers to establish his Base Line to adjust from, it may not be your tune at all.

With these kits the MAF's are close to the filters when the cooling fan from the tuner turns on it can create + pressure reading in the MAF and throw the base line off. Tuner continues to tune of bad base line. Happened to a few people here on the forum. Called Stillen and got no help.

Here is what I did to try to get 500 HP:
DW 650 injectors
CJM Fuel Return System
DW 300 fuel pump
928 Impeller
Ditched hose clamps and added pressure bands
Drilled out the intake and added AN12 fittings to flow more coolant
Removed battery and added 1/2 gallon reservoir for cooling
Added UpRev MAF's
Added Turbo Smart BOV
COG drive belt to eliminate slip

In the end, i saw 480 max and was plagued with leaks. Every weekend went through the car to fix leaks. Every tune power dropped. Every smoke check was always showing something new.

Good luck, its a good kit as is for daily driving and fun, 50 state legal and all.