p.1: Exterior pics and history
p.2: Performance Modifications (you are here)
p.3: Suspension modifications
p.4: Audio
This page covers performance modifications done to my
roadmaster.
Exhaust:
ATR 2.5" mandrel bent stainless steel cat-back.
ATR made some pretty sweet products for the Grand National. They went out of business, but their prodocts are second to none. This kit features four mufflers to reduce drone, as well as an H-pipe to balance exhaust pulses. A lot of B-body owners like their car to be loud... I prefer a quiet ride.
Clear Image Automotive Tri-Y headers
Ceramic coated in Satin black.
Headers are connected to cat-back via 304 stainless "extended hookup" pipes. I don't know how these will hold up to Quebec winters but I made sure to spray them with high-temp paint to minimize corrosion.
Eaton posi and 3.42 gears
The gears are from an older 9C1 caprice.
This was a definite upgrade over the stock 2.56 open differential. The super tall 2.56s, in conjunction with stock 28" tall tires made the RMS a DOG off the line. A more reasonable gear ratio (2.93) can be found in roadmasters equipped with the towing package.
Note: If you have the GM 8.5 rear in an early to mid-90s vehicle, make sure you upgrade your differential gasket to RDS 55028-1 which has the proper lubricating holes. The stock gasket does not have the appropriate lubrication holes and will end up damaging your axle shafts.
Transmission :
Transgo HD2 Shift kit: This shift reprogrammer addresses many of the shortcomings of the 4L60e transmission. This kit took 14 hours to install. If you do it yourself, take your time. Read the instructions several times and please refer to this site for supplementary installation information with great pictures.
EDGE 2800 stall torque converter
The stock 12" converter stalls at 1397 rpm. This new 9.5" unit really helps wake the car up.
Engine :
cold air intake
Comp cams pro-magnum 1.6 ratio roller rockers
CM 614 valvesprings
The 1.6 ratio roller rockers made a nice difference in the higher RPM range, as did the valvesprings. The stock ones are crap.
PCM :
Reprogrammed by Bryan Herter @ pcmforless.com.
91 oct tune & LT4 knock module
