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More Power
01-14-2008, 14:59
January 2008 - New Articles!


Dual Thermostats
Improving Cooling System Performance for the 6.5L Turbo Diesel
The new 130-GPM water pump increased coolant flow through the block and heads by 74%, and through the radiator by 9%. The motivation for increasing the coolant flow-rate was to help eliminate hot spots within the engine and to reduce cylinder head cracking. Dual thermostats were required to both increase the flow rate capacity and to prevent pressure surges within the cooling system that are possible when running a single thermostat. We learn more from GM employees about why we need dual thermostats when running the 130-GPM water pump.


Splayed Main Caps
for the 6.5L Turbo Diesel
For decades, splayed main caps have helped power merchants in the gas engine performance market provide a solution to cylinder block failures. Multiplying the power output of a factory engine can stress the block in ways the original engineers never imagined. Splayed main caps anchor the main webs to the pan rails, which help strengthen the bottom end and allow the engine to safely produce a lot more power. Since 2002, custom engine builders have begun adding them to the 6.5L diesel, not so much to make big power, but to reduce the possibility of main web cracking. Let's have a look at three different aftermarket splayed main cap designs for the 6.5L diesel, and consider what they might do to improve 6.5 reliability.


Towing EGTs
Does Adding Power Increase EGT?
The short answer is "not always". I had an opportunity earlier this year to perform a series of towing tests, comparing stock exhaust gas temperatures to those while using a VanAaken performance module for the LB7 Duramax. We've all seen the admonitions for installing a set of boost pressure/exhaust temperature gauges and a performance exhaust system before adding power. This has been and remains excellent advice, but more people than you know have added power while maintaining the factory exhaust system. Let's find out what really happens.

These three articles are available now in the Subscriber Area (http://www.thedieselpage.com/password.htm) of the web site.