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  1. #1

    Question Trying for mileage and happiness?

    I just bought a standard original bore 283 SBC to build for my family truck (1970 Chevy Longbed). Right now the truck has a .040 over 454 driving through a TH400 to a Dana 60 with 3.73 gears. LOTs of fun on the street, but you can't afford to go anywhere due to the 7 MPG mileage. So, enter the 283.

    I've had them before and they are happy little motors. I'll be putting 305 Vortec heads on this one for four reasons: 1.) to get modern chamber profiles, and 2.) smaller chambers for a CR bump, and 3.) I have them, and 4.) I can get modern accessory bracket bolt points.

    It'll be exhausting through the Vortec iron manifolds into a 2 1/4" dual system with H pipe (that's serving the 454 nicely). Intake is a dual plane medium riser manifold and initially it will be topped with my Holley 600. As more funds are available, I'll move to an after market TBI setup with O2 feedback.

    Targets are 200~225 HP at something like 4500 and 15~20 MPG with light throttle at 55 mph. Now the questions, how to build and what parts to use? I'm already leaning strongly in the direction of roller rockers as I use them on other motors to reduce friction. How about a roller cam? Total sealed rings? Certainly roller timing chain. HEI with custom vacuum curve?

    Any help with this and other ideas greatly appreciated by me and the planet
    Broc Luno,
    I like older stuff :)

  2. #2

    Default

    there are lot more things to be taken care of. not only timing chain and performance kit will help. autometic tunneling should be done. thats a great idea.

  3. #3

    Talking More parts fround

    Well there is more news. Turns out the spare heads I had are not vortec . Oh well, they are 601 305 H.O. heads with a 7 cc compression bump from the 60cc OEM 283 heads - these are 53cc. They also have 1.84 intakes which is a nice little jump from the 1.74 intakes on the 283 heads.

    While digging through the shop attic I came across some rams horn exhaust manifolds and a vacuum HEI. I'll mildly port the 896 heads and blend all. I also found an Edelbrock S.P.2 - P.2V aluminum intake that will mate with the 896 heads nicely I'll need a big base 2 barrel TBI to make that all work well. Anyone know of a 500 CFM 2 barrel TBI?

    Also came across a bunch of miscellaneous SBC brackets and such so I have about 95% of the parts. Looking for a nice roller cam for Truck & Rv applications. Any roller cams in 305's from the factory?
    Last edited by brocluno; 11-11-2009 at 10:09 AM.

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