383 Chevy Proharger - Late-Model 383 Buildup-Part 3

Getting the belt over the pulleys required a little trial and error. Usually, it's a piece of cake; simply loosen the idler pulley and slip the multi-grooved belt in place, and then retighten the idler. However, our best plan led to loosening the crank pulley, putting the belt on, then tightening down the pulley again. After we figured it out, it worked every time.

The single biggest accessory for a supercharged application on the street is an intercooler. Strategically mounted, it will considerably lower the air intake temperature, increasing the density of the air/fuel mix for bigger power gains. Since our engine will be static on the dyno, the boys at ATI sent along this water-to-air intercooler (used on boats) so that we can keep the intake charge as cool as possible. It bolted on to our special-made bracket. Neat setup!

Here Bob positions the hose leading out of the supercharger to the intercooler. Everything fit perfectly.

A bell-shaped hose is made to fit over the mouth of our Arizona Speed and Marine 58mm billet throttle body. Again, installation was smooth as silk.

With the ATI D-1 supercharger all bolted in place, our attention turned to the exhaust side of things. Contrary to popular belief, the exhaust is of equal-if not greater-importance when it comes to making power on a supercharged application. Here we were fitting a set of large-tube headers from TPIS. Although we won't run these on the dyno (since the Vrbancics have a myriad of pipes with all of the correct EGT hook-ups), we will more than likely use this set in the car.

The fuel delivery system of a supercharged engine is of paramount importance. As indicated in Part 2 of this series (Sept. '00), we used a state-of-the-art fuel pump and regulator from Aeromotive. The point of this photo is to show the boost-referenced regulator compared with the factory unit. The Aeromotive regulator allows full adjustment and is sensitive to the boost and vacuum created by the engine, altering the fuel pressure proportionately to prevent a lean-out situation from occurring.

The correct parts combination is important in every engine, but when it comes to supercharging it's even more so. Since we were basically limited to using the factory intake manifold, it was important to maximize its potential. For this we turned to the power mongers at Arizona Speed and Marine. They took a stock intake and ported it for better flow. And, they built up bosses to accommodate nitrous oxide nozzles. Hmmm, you can never have enough power, for sure.

Here's a comparison of the throttle body openings between the stock (52mm) (top) and Arizona Speed and Marine (58mm) (bottom) intake manifolds.

Here you can see the built-up area on the outside of the port that is machined for the nozzles, and the angle of the nozzles themselves.

The ASM manifold has its port gasket matched so there's a smooth transition between it and the cylinder heads. The process is basic; a little blue dye is applied to the port mouth, a scribe is used to transfer the gasket's opening to the manifold; and the scribe marks indicate where the ports need to be contoured to match the gaskets.

A hand-held die grinder with a carbide bit designed for cutting aluminum is employed to make the required changes in port configuration.

The same process that was applied to the ports is repeated on the mouth of the intake where the throttle body is positioned. Going up in size from 52mm to 58mm may not seem like a lot, but when it comes to airflow it is considerable.

Here's the precision-crafted ASM 58mm billet throttle body. Aside from the port matching, the nitrous boss install, and the addition of this beauty, the only other preparation our intake received took place at Extrude Hone, where an abrasive media is forced through the entire inside of the manifold under high pressure, leaving a near perfectly polished surface in its wake. Needless to say, we're sure that this 383 will have plenty of intake charge for making big power. Stay tuned for the series finale in next month's issue.