BAC Forum

General Boards => Technical Support => Topic started by: Glenn Scherrer on September 21, 2014, 11:53:08 PM

Title: C7. C9
Post by: Glenn Scherrer on September 21, 2014, 11:53:08 PM

What's the difference in a cat c7 and the c9 ?

Title: Re: C7. C9
Post by: Gerald Farris 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

Title: Re: C7. C9
Post by: Glenn Scherrer on September 23, 2014, 02:16:08 AM

The 3126 is the c7 or the c9 ?

Title: Re: C7. C9
Post by: Chuck Jackson 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.

Title: Re: C7. C9
Post by: Arden Smith 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.