Diesel Tuner's Blog

This document contains the data we gathered on the chassis dyno while proving out our Stealth series of turbos for the 2003-2007 5.9L Cummins.  This is real, experimental data and therefore may not be perfect.  It represents many hours and dollars of hard work by the team at Calibrated Power and is used by our staff to assist customers in the selection of the best turbocharger for their application.  This data was amassed by instrumenting the truck with a variety of gauges and probes from Banks Engineering and collating data after each steady-state test.   Below you'll find  Nick Priegnitz's personal thoughts on the data.  These are broken down into two parts, the first is an intro to what the data represents and how it was collected followed by a trends in data as seen through my eyes along with some takeaways.   

A quick note on power.  All dyno numbers are reported in 'Mustang RWHP'. Do any googling and you'll see that Mustang Dynos are very stingy.  If you're comparing to 'internet dynojet numbers' add back 12.5% to any dyno number reported here.  Example: if the Stealth 64 (Mach 1) reports 623rwhp on our dyno you can expect 623*1.125=700rwhp on a dynojet. 

Table of Contents: 

1- Turbo Descriptions

2- Steady State Towing test results with PID Info

     a. Lambda

     b. EGT

     c. Shaft Speed

     d. Boost

     e. Drive pressure (ratios)

3- Spool up Test 

4- Max Power Clean (AFR/Lambda limited)

5 -Max Power (Competition use)

6 - Video

7- Conclusion 

1. The turbos (from left to right)

1. OEM Stock HE351cw- Stock stock stock.  This turbo is a great example of what can be expected from trucks running stock boost limits, either without boost tuning or wastegate mods. 
2. OEM Improved HE351cw - This turbo is a stock core with a modified wastegate canister and rod adjustment to spec.  This upgraded wastegate uses a stronger spring to keep the wastegate circuit at higher drive pressures and also allows peak boost to reach about 37psi. 
3. Calibrated Power STR - This turbo uses an upgraded rotating assembly 60mm x '67 Beastwheel' as well as our upgraded wastegate canister matched to allow about 41psi boost pressure.  
4. Calibrated Power Stealth 64 -  This turbo uses an upgraded rotating assembly 64mm x '67 Beastwheel' as well as our upgraded wastegate canister matched to allow about 46psi boost pressure.  
5. Calibrated Power Stealth 67 -  This turbo uses an upgraded rotating assembly 67mm x '67 Beastwheel' as well as our upgraded wastegate canister matched to allow about 50psi boost pressure.

High powered diesel trucks usually represent a means of getting your toys to the adventure.  Whether it’s towing an open trailer full of fourwheelers and SxS’s, a boat, or the toy hauler, the ideal experience involves the driver and passengers in climate controlled comfort pulling in high gear without feeling compelled to watch the gauges.  The Roxor represents a departure from this.  It’s open cab and 1940’s era suspension doesn’t just take you to the adventure. Driving it is the adventure. 

The Mahindra Roxor has been out playing in fields and on trails for years now. We've all seen the old styled-Jeep looking vehicle and wondered what's going on here? Well, like all other diesel markets, the Roxor aftermarket is growing in volumes. You're diesel enthusiasts, these Roxor owners are just like you. Once they realized these machines have much more potential when modifying, well you know the drill. To the Garage they go.

Balancing Performance, Heat, and Reliability

Hold a cigarette lighter up to your thumb for a split second, and you can probably tolerate it.  Hold a lighter up to your thumb for 5 seconds, and you'll probably want to get the ice water ready.  During those 5 seconds you're quickly using up your thumb's heat buffer.  This parallels exactly what happens inside your engine when pulling up a grade at GVW or passing on the highway.  Your engine has been well engineered with heat transfer pathways, designed to dissipate heat from the 'front lines' the same way the blood in your veins moves heat away from your skin in the cigarette lighter experiment.  In the performance realm we are mainly concerned with 2 elements of these pathways, the first is the amount of heat the system can hold and the second is how quickly the system can move heat from the source. 

"Your engine has well engineered heat transfer pathways to dissipate heat . . ."