Installing an Edelbrock Power Package on a Pontiac 455, Pt 1

Posted on June 2, 2015 by Jefferson Bryant in Engine, Racing, Tech // 0 Comments

Performance modifications are typically a matter of trial and error, looking for that magic combination of what works for your engine in your situation. All of your buddies are using this brand-x cam with these heads, but you have a different set of heads and that same cam just doesn’t seem to have the same punch, so it’s back to the drawing board. This same tune resonates throughout the world of automotive enthusiasts that practice the art of modifications. With so many choices, it can be difficult to settle on a select group of parts, and how they will interact together is anybody’s guess. There is however, a simpler solution for those of us who want extra performance, without acting as a guinea pig- the package deal.

There are several manufacturers that offer performance-enhancing packages, from intakes and carbs, to complete motors. One of the most complete and efficient package deals comes from Edelbrock. Well-respected and certainly not a new-comer, the Edelbrock Power Package products offer the performance enthusiast a simple, yet effective way to increase the power output of their engine with one purchase. All of the components are designed to match each other, optimizing their effectiveness. This takes all the guesswork out of choosing your parts and ensures that the parts will work well together and be reliable, a key component of any modification. Edelbrock offers their Power Packages in 2 levels- emissions-legal Performer series and non-emission controlled Performer RPM. The RPM level offers more power and is suggested for vehicles that do not have to be emissions tested. The Performer series offers a power band from idle to 5500 rpm, while the Performer RPM packages run 1500-6500 rpm.

For our 1969 GTO Judge convertible, we chose to upgrade the original 400 ci engine with a Performer RPM package. This engine already had 10:1 forged pistons, headers, Ram Air III heads and a nice camshaft, putting out in the neighborhood of 350 hp, but we wanted a little more. The Performer RPM packages require 9.5:1 compression, which we’re good with, but the new aluminum heads are based on the Ram Air IV design, which feature D-shaped ports. This caused a little bit of a ruckus when it came time for headers, but we’ll get to that in the next article.

The camshaft for the Performer RPM kit is dyno-matched to the heads and intake, creating the perfect combo for making power. The new kit comes with cam and lifters, but you are on your own for pushrods. The heads for the Performer RPM kit come complete with valves and valve springs. We used a set of roller rockers on our install to reduce friction.

The installation of the kit is pretty straightforward, though there are some things that need to be addressed. The Edelbrock Power Packages involve some serious wrenching, getting into the internals of the engine. Care must be taken during the installation to ensure everything will work correctly and have longevity. Installing a camshaft without pre-lube will wipe out a cam within the first couple of minutes of start-up. The head bolts must be torqued in a specific sequence. It is important to make sure you check your installation instructions for the specific sequence for your engine. Once the heads and cam are installed, the pushrods and lifters can be installed and valve lash set.

Next article, we will go through the top end of the package, as well as deal with the headers, which were less than fun. For now, read up on the heads and cam install then get your own.

1. The original 400 in the GTO had a healthy cam and a set of stock iron Ram Air III heads, but it was time for a little more punch. The Performer RPM Power Package should do the trick.

$2.The radiator and stock A\C condenser needs to be removed in order to do the cam swap. We could have pulled the motor, but it isn’t necessary for this swap.$

2. The radiator and stock A\C condenser needs to be removed in order to do the cam swap. We could have pulled the motor, but it isn’t necessary for this swap.

$3.The engine had an Edelbrock Performer intake which is better than stock, but not quite up to par with the rest of the new parts, so it goes on the spare parts shelf. We also pulled the water pump\timing cover.$

3. The engine had an Edelbrock Performer intake which is better than stock, but not quite up to par with the rest of the new parts, so it goes on the spare parts shelf. We also pulled the water pump\timing cover.

4. The valley pan cover needs to be saved for reuse; the package kit does not come with gaskets and specialty parts.

5. The iron heads weigh about 70 pounds, so lift carefully. We pulled the manifolds off at the same time.

6. The old cam slides right out. We didn’t want to change the cam bearings, so we removed the cam slowly and carefully.

7. Corey Murfin of Redline Auto Sports scraped the block clean for new gaskets. This is important for a proper seal.

8. The new Edelbrock cam was slid into the block using a long bolt as a handle. The red goop on the cam journals is pre-lube; forget to put this stuff on and you might as well throw the cam away.

9. The double rolling timing chain that came included in the kit was installed straight up, as in zero timing was added or taken out from the cam.

10. The lifters were also treated to a generous helping of pre-lube as well and then dropped into the lifter bores.

11. New Felpro performance gaskets were set on the block.

12. This shot shows the headers in place before the heads went on the motor. The headers fit the car, but gave us a little trouble, more on that in next article.

13. The new aluminum heads were dropped on the block.

14. We also bought a set of Edelbrock head bolts as the originals won’t fit these new heads. Inside the box were these bolts from ARP. The lube shown here is very important, as it lubricates the threads and ensures proper torque readings.

15. The threads were coated with lube and threaded into the block.

16. There are 3 sizes of bolts for the Pontiac 400, so pay attention. The bolts are snugged up tight, but not torqued yet.

17. Once all the bolts are in, they are torqued down in a sequential fashion. The sequence is engine specific, so check your install manual when torqueing the head bolts. If done wrong, the heads can warp.

$18.The pushrods and rockers were installed, then the valve lash was set. Setting the valve lash on hydraulic lifters is done by rolling the motor over to just past valve opening, then tightening the rocker until the pushrod just stops moving, and then a 1\4-turn more.$

18. The pushrods and rockers were installed, then the valve lash was set. Setting the valve lash on hydraulic lifters is done by rolling the motor over to just past valve opening, then tightening the rocker until the pushrod just stops moving, and then a 1\4-turn more.

19. We used poly rocker locks which work better than the stock style. The allen lets you hold the tension while the hex head nut is tightened.

20. The timing cover assembly was reinstalled at this point.

21. The stock rockers could be used, but we went for roller rockers, which reduce friction. The main problem with these rockers is that they just barely cleared the new valve covers.