Author Topic: C7. C9  (Read 5238 times)

Glenn Scherrer

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C7. C9
« on: September 21, 2014, 11:53:08 PM »
What's the difference in a cat c7 and the c9 ?

Gerald Farris

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Re: C7. C9
« Reply #1 on: September 22, 2014, 04:18:33 AM »
Glenn,
The C7 and the C9 are basically similar medium duty truck engine designs. They both use the HEUI ((Hydraulically Actuated Electronically Controlled Unit Injector) fuel injection system. The main difference is that the C9 at 8.8 liters is larger than the 200 pound lighter C7 at 7.2 liters. Therefore, with the 1.6 liter larger displacement, the C9 will generate 50 to 75 more horsepower than the smaller C7.

Gerald

Glenn Scherrer

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Re: C7. C9
« Reply #2 on: September 23, 2014, 02:16:08 AM »
The 3126 is the c7 or the c9 ?

Chuck Jackson

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Re: C7. C9
« Reply #3 on: September 24, 2014, 12:15:58 AM »
The later C9s (2007+) are 9.3 liters and do not have the HEUI. They use the common rail fuel injection system and are rated up to 425hp.
2019 Newmar Dutch Star 4328
2008 Beaver Contessa 40' Pacifica 425 Cat - Sold

Arden Smith

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  • 98 Monterey 36\' 300 Cat 3126
Re: C7. C9
« Reply #4 on: September 24, 2014, 01:30:19 AM »
The 3126 is a c-7. There is a difference in the 3126 and the 3126B. I believe the difference to be the 3126B has an intake manifold cast together with the head. I also believe this change was done about 1998.
Arden Smith
98 Monterey 36' 3126 300 CAT