6.5 - More power?

[johndeere147]

I'm looking at a Hummer H1 with the 6.5 diesel engine. It's a beautiful truck and I'd like to buy it, but I notice that it doesn't make a heck of a lot of power. What gives? A friend told me that diesels make a lot of power easily with exhaust, turbo, intake, and chip upgrades but my Internet research tonight doesn't show anything in the way of high performance 6.5 diesels. Am I missing something, or is it impossible to do anything with these engines?

[Mark Rinker]

Welcome aboard!

Your friend is right. A 6.5L can be 'turned up' quite easily; however you aren't going to find alot of aftermarket performance parts marketed specifically for the H1, you'll likely have to assemble a custom solution based on what you have, how much you want to spend, and what you want to attain.

My understanding is the 6.5L in the Hummer H1 is usually a naturally aspirated (non-turbocharged) version of the same engine that was found in GM trucks - that always were paired with a turbocharger - in the same production years. There is a long and storied (read:somewhat problematic) evolution of the 6.5L engine, with various designs, block castings, and manufacturers. Some are better candidates for performance enhancements than others. You should be able to find out alot about what version of the 6.5L powerplant you have by researching your block casting numbers. Search the 6.5L forums, and 6.5L articles elsehwere on The Diesel Page website.

If you have a 'NA' version of the 6.5, adding a turbo would give you the ability to add additional fuel rate to the engine, and have the air available to burn it efficiently. However, adding a turbo to a non-turbo applicaton may be non-trivial mechanically. I have no idea how much, or how little space is available underhood of the H1. My guess is if there is a will, there is a way as turbocharged 6.5L engines have been swapped into 3rd gen'r Camaros and Corvettes!

At any rate, you have arrived in the right place in cyberspace for the best tuning information, turbocharging discussions, exhaust and gauges to monitor the 6.5L in a performance application...keep searching, reading, and learning!