Back in 2005, GMHTP went old school with a '94 LT1 Camaro, installing a bevy of performance parts, including headers, an exhaust, 1.6 roller rockers, aftermarket opti, new coil and wires, a timing set, and a custom tune. We were rewarded with 48 horses and 31 ft-lbs at the wheels ("Old School," July/Aug. '05). When a high air/fuel ratio was seen on the dyno, a new fuel system and 24-pound injectors were added, and with a new tune, the Z responded with an additional 16 hp ("Old School Fuel," Nov. '05).
Old School has now reached more than 140,000 miles, and is still running like a top; however, this last year saw its cooling system start to break down. As OS spends most of its time in Southern California, the relentless heat has regularly pushed the temp gauge into unsafe territory and 235-plus coolant temps became the norm, despite a 160-degree thermostat and a fan switch. Time for a radiator upgrade.
The solution was Fluidyne and its High Performance Direct Fit radiator for '93 to '02 Camaros and Firebirds (PN FHP11-93CAM). It is a high-efficiency, 38mm radiator with a brazed aluminum core, polished aluminum tanks, and everything necessary for installation, and it retails for $679.
For the installation, we turned again to Robert Barth of Strictly Performance in Van Nuys, California. Barth and his staff know their way around EFI GMs, and made quick work of this radiator swap. Follow along to find out how cool our LT1 became.
Lti running hot?
In Old School's case, the original high-mile radiator was simply worn out; however, in many LT1 cars, the culprit can be found in other parts of the cooling system and factory air ducting. If you are seeing higher-than-normal temps, be sure to check for these problems before assuming the radiator is shot:
Leaky cooling system
Malfunctioning radiator cap
Obstructed radiator/condenser area (leaves or other debris)
Broken/missing factory air dam
Air in system: bleeder screws by thermostat housing
Incorrect LT1 thermostat: use long 160-degree version
Inaccurate coolant temp sensor on water pump
Inaccurate temp gauge sensor in driver-side cylinder head
Bad fan fuses/relays in underhood fuse box if fans malfunction
For testing purposes, we enlisted a Tech II Scan Tool to monitor coolant temperature. With both the original and Fluidyne radiators, the Z28 was warmed up and driven around for several minutes before coming back to the shop for the temp reading. Both tests were performed with the cooling fans and air conditioning on.
Original radiator test - july 2006
Outside temp: 100 degrees
Coolant temp: 230 degrees
Fluidyne radiator test - august 2006
Outside temp: 94 degrees
Coolant temp: 170 degrees