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Help me rebuild and upgrade my Chevy Small-block in my 91 Suburban

Discussion in 'GM Powertrain' started by Crawdaddy, May 24, 2012.

  1. Crawdaddy

    Crawdaddy Moderator Staff Member Platinum Contributor 1000 Posts

    Hey guys!

    Well, I’m really thinking about pulling my Chevy 350 small block out of my 1991 Suburban, and giving it a nice rebuild and upgrade. So, I’m coming to ya’ll to give me ideas of how I should proceed with the rebuild. The goal is to at least match the horsepower and torque numbers of the Chevy big block of the era. More power than the big block of the era’s all cool, but I need to at least match them. I think it’s doable. Chevy’s power ratings for the small-block that year was 210HP@4000RPM and 300TQ@2800RPM. The big block was rated at 230HP@3600RPM and 385TQ@1600. Now that I looked it up, I know I can easily blow by the big block numbers…

    Now for the important part…money. Let’s assume I can spend roundabout 2 grand on the project.

    My primary application for the motor and Suburban are cruising down the highway at 70mph while getting the best MPGs possible, and towing my camper that weighs, let’s say around 11,000 pounds. (The weight is an overestimate I hope, but let’s just say that…) The truck also idles a good bit, so it needs to be idle-friendly. It’s backed up by a TH700R4 transmission that will be rebuilt/replaced with an upgraded unit in the process and a 14-bolt full-floating rear axle with 4.10 gears.

    Now that that’s said, let’s lay down a few ground rules:

    • No carbs
    • No full-fuel injection systems, throttle-body injection only
    • The engine must be able to be fueled by a throttle-body injection system compatible with the stock computer (with or without a custom chip burned for it)
    • No swapping to a big block
    • In your cost-analysis and speccing, assume that I have a 2-bolt main block which will most likely need/want to be swapped to a 4-bolt main block.

    I was thinking things for this build along the lines of a bigger cam, new pistons, rings, rods. Fueling is a problem on my mind. I don’t know if the stock throttle-body will be able to dump enough fuel. Perhaps there are bigger injectors I can get for it. I heard there’s a mod where some people have been using big block throttle-body injection setups that work with the factory computer somehow. I’m open to moving up to a stroker, but I don’t think I can fit that into my budget.

    I’ve never built a performance engine before, so I’m clueless as to what parts are good, what parts are better, what brands to lean towards or shy away from, and what is useless for my needs. I’m also wondering if anyone knows of a good performance transmission company that can get me a heavy-duty 700R4 transmission that will stand up to the abuse of towing that much weight. I do have plenty of cooling and outboard filtering of the transmission fluid already.
    Last edited: May 24, 2012
  2. Crawdaddy

    Crawdaddy Moderator Staff Member Platinum Contributor 1000 Posts

    I was thinking about maybe going with the Power Package from Edelbrock. They claim it's more power while still keeping the stock TBI, so that sounds like the ticket I was looking for. The "package" is comprised of an intake, heads, cam, and timing chain set. They also claim to provide a computer chip free with proof of purchase of the heads, cam, and intake. Sounds like a winner to me. I can't seem to find a part number for the whole package, so I guess they expect me to buy it piecemeal and assemble them together. The package, plus a rebuild kit with new pistons is going to cost me in the neighborhood of $2500, plus let's say $500 or so for block work (dip and clean block, magnaflux, resize bearing surfaces as needed, etc) at the machine shop for a grand total of 3 grand. That's about $1000 bucks over, but it seems to be worth it. Opinions?

    Here's a link to the Edelbrock page describing the Power Package. It's the 305, 350 V8 T.B.I. 1987-95 line.
    http://www.edelbrock.com/automotive_new/mc/power_package/performer_power_packages.shtml
  3. ahmitchell1

    ahmitchell1 New Member ROTM Winner 1000 Posts

    Go to that link you just posted and click on the PDF on the top of the page it's says to go to page 12 and 13 to order them in a single box or u can order them one piece at a time
  4. tbplus10

    tbplus10 Super Moderator Staff Member Platinum Contributor 1000 Posts

    When you order the package from whichever specific vendor you use you'll need to let them know you want the package and they should have a package part# to use for ordering. Edelbrock doesnt post all their part numbers on the website.
  5. ahmitchell1

    ahmitchell1 New Member ROTM Winner 1000 Posts

    #2088 looks to be the one for your truck on page 13 of their catalog
  6. Crawdaddy

    Crawdaddy Moderator Staff Member Platinum Contributor 1000 Posts

    I'm not so sure about that. 2088 seems to be listed with the "RPM" designator, indicating to me it's the Performer RPM package, which is not optimized for the RPM range I am going to be operating in. I guess I'll have to call Edelbrock to determine the correct part number for the package. I would certainly hope the package is cheaper than buying each part individually.
  7. ahmitchell1

    ahmitchell1 New Member ROTM Winner 1000 Posts

    Yea my bad the guides on there with all the part numbers you need for sure
  8. Crawdaddy

    Crawdaddy Moderator Staff Member Platinum Contributor 1000 Posts

    Well, it's looking like I'm not going to get the additional power I was looking for solely by adding the Edelbrock PowerPack. According to this graph:

    [​IMG]

    I'm only scoring another 25 foot founds of torque in the low end where it counts for me. So, I need to go back to the drawing board and find another route around this. Any ideas?

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