The Official Vortec 454 Info thread

SS Performance said:

Is it possible to use the L19 accessory drive on the L29? I'm wondering because this would shift the A/C compressor to the passenger side. Then you could replace the intake with a standard dual plane style intake. This would provide options for making more power.

Just wondering
Thanks
Craig

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Its just standard BBC stuff. The serpentine belt drive systems require a reverse rotation water pump, but they all have the same mounting provisions and are interchangeable. You can put a standard BBC dual plane intake manifold and carburetor on an L29 with the stock accessories. They sit off to the side and high enough that they will clear the intake with no issues. The entire system is designed for low RPM torque and runs out of steam around 5k rpm. You can shift that power band into a higher RPM range with cam and intake to make more peak HP, but you will be losing out on low RPM drivability.

BeXtreme said:

Its just standard BBC stuff. The serpentine belt drive systems require a reverse rotation water pump, but they all have the same mounting provisions and are interchangeable. You can put a standard BBC dual plane intake manifold and carburetor on an L29 with the stock accessories. They sit off to the side and high enough that they will clear the intake with no issues. The entire system is designed for low RPM torque and runs out of steam around 5k rpm. You can shift that power band into a higher RPM range with cam and intake to make more peak HP, but you will be losing out on low RPM drivability.

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I figured that. The problem I see is the A/C lines run down the drivers side over the edge of the intake. It looks like they would interefer with injectors or fuel rails if you tried to use port injection.

SS Performance said:

I figured that. The problem I see is the A/C lines run down the drivers side over the edge of the intake. It looks like they would interefer with injectors or fuel rails if you tried to use port injection.

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I'm confused. What are you trying to do? The L29 is port injection. The AC lines wouldn't interfere with the Port injection or a carb setup with dual plane intake.

Yes the L29 is port injection. But the intake is a limiting factor when trying to achieve more power. With a 4150 style intake modified to accept injectors in the intake runners it appears that the A/C line would interfere with the fuel rails for those injectors, they would be trying to occupy the same place along the drivers side of the engine.

Is it possible to run L19 or L29 accessories on a 8.1L

Dropped88 said:

Is it possible to run L19 or L29 accessories on a 8.1L

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Not easily. 8.1l has coolant cross over in the front

...and the heads on the 8.1 mount about half-an-inch higher, so the bolt holes on the brackets won't line up with the holes in the heads.

What was the question again? Regarding accessories?

How did the C3500HD and the Kodiak with the factory 8.1 accessories work? I thought those mounted the AC compressor high similar to the position of SBC/BBC?

SS Performance said:

Yes the L29 is port injection. But the intake is a limiting factor when trying to achieve more power. With a 4150 style intake modified to accept injectors in the intake runners it appears that the A/C line would interfere with the fuel rails for those injectors, they would be trying to occupy the same place along the drivers side of the engine.

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I don't think that would be the case. The intake isn't the limiting factor for more power, the intake is designed for low RPM. Switching to a single plane 4150 style and running dual fuel rails puts the rails in the same location the runners are on the stock manifold, so I don't think it would be an issue. I could see a tunnel ram style having issues, but I doubt it would matter if that was on the driver or passenger side.

https://www.summitracing.com/parts/...oIO1-jB4wQRVcRVNw863K1nGkWtVJk7caApNnEALw_wcB

stutaeng said:

What was the question again? Regarding accessories?

How did the C3500HD and the Kodiak with the factory 8.1 accessories work? I thought those mounted the AC compressor high similar to the position of SBC/BBC?

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Correct, top driver side A/C mount just like a 7.4 Vortec. Wild guess? Probably their own unique accessory drive brackets for a GMT455 w/8.1. The 3500HD was mostly a "parts bin" design pulling things off the shelf that already existed for other models, but that doesn't necessarily rule out a few special-made parts, IMO. I mean - they had to come up with engine harness, stuff like that for these trucks. Also keep in mind while the U.S. only got them for 2 years, they continued producing them for the Mexico market for several more years with the 8.1 (and 6.5td) - through at least 2006 or so.





Richard