Now that our Project LT1 Formula had developed a taste for 13s during our last visit to the dragstrip, thanks to the Thunder Racing Performance Package, it was time to unlock more emissions-legal ponies with another slew of bolt-ons. To that end, mid-length headers, Y-pipe, high-flow cat, underdrive pulleys, rocker arms, coil, and a custom tune were to be the weapons of choice-with a total cost under $1,500. Installation of these components should have no effect on reliability with the high-mile LT1, yet still net significant performance gains. Hopes were set on nearing the last effort with over 20 rwhp and two-tenths ET reduction, assuming favorable weather.
The success of this install would largely depend upon two things: the quality of the components and the quality of the install. On both fronts it seems the Formula was pretty well covered, especially since Ron's Custom Auto would be doing the wrenching. Given the LT1's older-style design and unique idiosyncrasies, there were few technicians in the Northeast other than Junior Perez your author felt comfortable handing the keys to. Junior has changed more than his share of Optisparks (not to mention wrestling on sets of headers) down at the Kenilworth, New Jersey shop. In fact, in addition to Ron's loyal group of GN customers there are quite a number of high-powered Impala SSs. For Junior's sake, we were hoping this would be a simple, straightforward install that wouldn't take more than a day and a half, but that would depend largely upon the Firebird's cooperation and the parts we intended to install.
Given the F-body's naturally low stance and the desire to stay completely emissions-legal, PaceSetter Mid-Tube Headers (PN 72C1335) were given the nod. PaceSetter developed these pipes from scratch to match the LT1's D-shaped ports not to mention utilizing the factory EGR and air injection hookups, which is why they pass emissions in all 50-states. These 1 5/8-inch primary headers use mandrel bent 16-gauge steel tubing with 3/8-inch, CNC-machined flanges. Both the headers and Y-pipe (in our variation) came with the 2,000-degree ARMOR Coat ceramic coating. All the bolts, hardware, and gaskets were included along with the Y-pipe. Believe it or not, these budget-minded headers retail for only about $615. For an extra $190 you can also pick up a MONZA Universal 3-inch high-flow catalytic converter (PN 80-0028) instead of reusing the stock one, which is exactly what we did. In case you are wondering, MONZA is a subsidiary of Pacesetter.
After having such luck with COMP Cams 1.6 ratio rockers (PN 1418-16) on the Old School project Camaro (GMHTP, July/Aug. 2005), we decided to stick with what works. These sturdy steel pieces have a stock look and similar dimensions, which require no modification to the stock valve covers for clearance. By moving up to a 1.6 ratio, from the stock 1.5s, lift is increased from .448/.459-inch to .478/.489 for a noticeable performance boost, while still being virtually undetectable to curious ears-perfect for building a real sleeper. Since they are made of steel, there should also be less deflection than with an aluminum rocker for greater reliability and a more full actuation of the valve (or more cam lift). Retail price is about $175.
PaceSetter Mid-Tube Headers...
PaceSetter Mid-Tube Headers and Y-pipe (PN 72C1335) combined with a MONZA 3-inch high-flow cat (PN 80-0028) will allow a vast improvement in flow for about $800 total, while still being 50-state emissions-legal. Connected to one of the 1 5/8-inch mandrel-bent steel primaries on each side are hookups for the EGR and air injection systems for use with the factory emissions equipment. These pipes also carry PaceSetter's 2,000-degree ARMOR Coat, however, these headers are also available in a simple black painted finish for less cheddar.
To begin removing the Y-pipe,...
To begin removing the Y-pipe, Junior uses a blowtorch to free up the bolts that connect it to the exhaust manifolds.
Using a 15mm socket with a...
Using a 15mm socket with a long extension as seen here, the two bolts on either side of the flange are finally unscrewed.