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Old 06-12-2008, 12:02 PM   #1
JCampbell
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Engine Build...

I’m gearing up to do some engine work on the dually and I would like to get a few opinions.

Basically, I want something hotter than your average one ton 454, but still perform reliably “as a truck”. In other words, I don’t want to build a cam’d up, stroked monster motor that’s so radical, it fails as a good towing/hauling motor.

I know that when you start doing these types of mods, that fuel mileage decreases are inherent, but I’m hoping the NV4500 that I plan to swap in will negate any reduction in fuel mileage on the highway. At any rate, try to keep “decent” fuel mileage in mind. When it’s all said and done with the motor & trans, I’d like to be able to get around 15 mpg.

I was thinking intake, cam and carb, but I’m basically lost on the specifics of those items. I know Edelbrock sells those “kits” that have the intake, cam & carb that are supposedly matched for performance, but I’m not sure that the kit they sell for the big blocks would be the best bet for this application.

Any suggestions?

Oh, and it’s a California truck, so everything needs to be 50 state legal.
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Old 06-13-2008, 09:20 AM   #2
manimal
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Re: Engine Build...

You could build a 9.0:1 496. Large oval port heads like 049's,they also have open chambers,use a dual pattern cam like Comp CAms Xtreme 4x4 cams,an Edelbrock performer 2-0 intake,and a good set of headers/high flow exhaust.
The 496 wont have to work as hard as the 454 and may deliver decent mileage.
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Old 06-13-2008, 11:37 AM   #3
Marv D
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Re: Engine Build...

Quote:
Originally Posted by JCampbell View Post
Basically, I want

...something hotter than your average 454,
...still perform reliably
...a good towing/hauling motor.
...try to keep “decent” fuel mileage
...Oh, needs to be 50 state legal.
Isn't that called wanting your cake and eating it too,,, with Ice Cream,,, served by a hottie in a tiny bikini...

LOL sorry, couldn't resist.. it's just a pretty tall order. Probably the best way to achieve what your wanting is going to be a EFI. No carb can balance that 'fuel efficiency' and 'performance' like electronic fuel injection. I know a couple of guys building / driving 468 BBC muscle cars running the Holley 950 controller and the port injection setup. One buddy is running a 455" all aluminum tall deck SMALL BLOCK on pump gas making 700 HP, drove it on the power tour, got an average of 16mpg,,,,, and dyno'd over 1000HP with a 300 hit of nitrous. So don't think EFI is a power limiting system. And don't think you can ge the same efficiency out of ANY carb. For what your looking for,, I'd HIGHLY suggest you consider a MPFI 468. With the cost of fuel today I really think it would pay for it's self if you do much driving.
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Last edited by Marv D; 06-13-2008 at 11:39 AM. Reason: sp
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Old 06-13-2008, 12:11 PM   #4
Pyrotechnic
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Re: Engine Build...

Basically, you want to make the engine as efficient as you can. Get the compression up to 9:1, run a cam with more lift but choose one that keeps the RPM range in the idle-5500 range. Make sure the heads are free flowing, but are still matched to the power range you are aiming for. Headers and dual high flow catalytic converters would also help you out.

Though if you must be emissions legal, maybe a Vortec 454 swap from a 90's truck would be the way to go, since in stock form with the stock computer, emissions shouldn't be a problem for it.
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