The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Engine & Drivetrain

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 06-12-2008, 12:02 PM   #1
JCampbell
Account Suspended
 
Join Date: Apr 2008
Location: Hesperia, Ca
Posts: 1,332
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.
JCampbell is offline   Reply With Quote
Old 06-13-2008, 09:20 AM   #2
manimal
Registered User
 
manimal's Avatar
 
Join Date: Oct 2006
Location: Southern Kalifornia
Posts: 3,066
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.
-Lance
__________________
------------------------------------------------------
-Lance
2000 Chevy C2500, 5.7, 4L80e
1999 Suburban K2500, 7.4, 4L80e
1980 Camaro..son's car...PROJECT
manimal is offline   Reply With Quote
Old 06-13-2008, 11:37 AM   #3
Marv D
Registered Truck Offender
 
Marv D's Avatar
 
Join Date: May 2008
Location: hells training ground (aka Ariz)
Posts: 3,118
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.
__________________
Still playin with trucks, even at my age!

When you're dead, it's only a problem for the people around you, because you don't know you're dead.
.....It's kinda the same when your STUPID.


I just did my taxes and reviewed my SS statement. Thanks to the current administration it looks like I will only have to work till noon on the day of my funeral.

Last edited by Marv D; 06-13-2008 at 11:39 AM. Reason: sp
Marv D is offline   Reply With Quote
Old 06-13-2008, 12:11 PM   #4
Pyrotechnic
Registered User
 
Pyrotechnic's Avatar
 
Join Date: Feb 2007
Location: Austin, TX
Posts: 3,930
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.
__________________
1977 GMC Sierra Grande
Pyrotechnic is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 08:51 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com