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  1. #1
    Fuel Injected! gregs78cam's Avatar
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    Cam advice

    I have had a buddy's '92 1/2T 5spd sitting here for a while that originally needed just a clutch problem fixed, but last summer when we went to start it, #8 cylinder was blowing back through the TB. So we tore it out, and found some bad news. Any way it has been sitting here since, and today we just went a picked up another shortblock, in really good condition, for $100. Well the guy who had it tossed the lifters when he took it out, so now I am trying to decide what to do with it. It supposedly has a cam that is one step above stock, which is kind of what I would like to have in it anyways. Now, I have never used a new set of lifters with an old cam, and I don't think I want to try now. Here is what I see as my options.
    1. Pull the cam/lifters out of the original engine and see if they are usable (which may be a possibility), and re-use them. $ = Free
    2. Buy new 'stock' cam/lifters and put them in. = ~$100
    3. Buy new 'RV' cam/lifters = ~$150
    4. Pull-N-Save a set of roller lifters, retainers, spider, then get OEM/RV roller cam. I don't know what the cost of this will be but I am sure most of it will the cam. Does anyone have any advice as to what cam I should look at. And does anyone know of any good deals on GM cams that might work well, for a reasonable price. If I could get a roller cam, even a factory stock one, for around $100 that would be great. If I were to find a Vortec V8 in PnS, would that cam/lifters/retainers/spider work in this engine?

    Thanks guys.
    1978 Camaro Type LT, 383, Dual TBI, '7427, 4L80E
    1981 Camaro Z-28 Clone, T-Tops, 350/TH350
    1981 Camaro Berlinetta, V-6, 3spd
    1974 Chevy/GMC Truck, '90 TBI 350, '7427, TH350, NP203, 6" lift, 35s

  2. #2
    Fuel Injected! jim_in_dorris's Avatar
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    If the block you got has the setup for a roller cam, then a set of roller lifters, retainers and spider from pull-n-save might be the way to go. I wouldn't, because a new set is just good insurance. The spider and retainer on the other hand are not wear parts, I would reuse them. An LT4 hot cam can be picked up lightly used for as little as $75 with a little internet digging. Easy to install and will put a grin on your face without putting a dent in your wallet.
    Square body stepsides forever!!!

  3. #3
    RIP EagleMark's Avatar
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    If it can roller lifter look for an LT1 cam pull, there were lots of them in $75 range awhile back...

    If not I vote #1...

    1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
    1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
    -= =-

  4. #4
    Fuel Injected! gregs78cam's Avatar
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    Quote Originally Posted by EagleMark View Post
    If it can roller lifter ...
    Oh I know, not only does it have the bosses in the valley, they are already threaded.

    I was looking at those but I think the LT1 and LT4 might be too much lift to try to get away with on factory truck valve springs. I was thinking more along the lines of the 87 350ci Corvette and IROC-Z Camaro with 202/206 @.050, and .403"/.415" and a very TBI friendly 115 LSA. I guess I will head over to TGO tomorrow, err....today and see whats out there. Thanks.
    1978 Camaro Type LT, 383, Dual TBI, '7427, 4L80E
    1981 Camaro Z-28 Clone, T-Tops, 350/TH350
    1981 Camaro Berlinetta, V-6, 3spd
    1974 Chevy/GMC Truck, '90 TBI 350, '7427, TH350, NP203, 6" lift, 35s

  5. #5
    Super Moderator dave w's Avatar
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    Roller camshaft conversion from a Vortec L31 5.7 liter engine is what I'd personally do, if the block is able to be converted to roller camshaft. If the block has a fuel pump block off plate bolted in, then the block is likely a good canidate for a roller cam conversion. If the fuel pump mounting is cast completely closed, (no hole for a fuel pump push rod) forget the roller cam option.

    If I couldn't do a roller cam conversion, I'd go for option #3. I would use a re-ground camshaft to save a few $$. I get my re-ground performance cams from Oregon Cams http://www.oregoncamshaft.com/ I can usually get flat tappet cam, lifters, and timing chain with gears set for about $110.

    dave w
    Last edited by dave w; 03-27-2013 at 02:31 AM.

  6. #6
    Fuel Injected! gregs78cam's Avatar
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    So it looks like I may have scored a used LT1 cam and lifters, along with some other 'goodies' thrown in for $50+shipping. Now what I need to know is, has anyone used the factory LT1 cam with stock TBI heads, i.e. the valves spings will work fine right? I mean we are only talking about 0.050" more lift.
    1978 Camaro Type LT, 383, Dual TBI, '7427, 4L80E
    1981 Camaro Z-28 Clone, T-Tops, 350/TH350
    1981 Camaro Berlinetta, V-6, 3spd
    1974 Chevy/GMC Truck, '90 TBI 350, '7427, TH350, NP203, 6" lift, 35s

  7. #7
    Fuel Injected! gregs78cam's Avatar
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    Dave, what exactly makes the blocks with a closed off fuel pump mounts not able to be converted? This block has the spider bosses tapped, the tops of the lifter bores machined, and no hole for fuel pump pushrod. The only thing I don't know for sure about the cam retainer plate mounting holes. But I am pretty sure I can drill/tap those holes in it if they are not.
    Last edited by gregs78cam; 03-27-2013 at 05:50 AM.
    1978 Camaro Type LT, 383, Dual TBI, '7427, 4L80E
    1981 Camaro Z-28 Clone, T-Tops, 350/TH350
    1981 Camaro Berlinetta, V-6, 3spd
    1974 Chevy/GMC Truck, '90 TBI 350, '7427, TH350, NP203, 6" lift, 35s

  8. #8
    Super Moderator dave w's Avatar
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    Quote Originally Posted by gregs78cam View Post
    Dave, what exactly makes the blocks with a closed off fuel pump mounts not able to be converted? This block has the spider bosses tapped, the tops of the lifter bores machined, and no hole for fuel pump pushrod. The only thing I don't know for sure about the cam retainer plate mounting holes. But I am pretty sure I can drill/tap those holes in it if they are not.
    I've only worked on a dozen or so TBI engines, so my limited sampling of TBI engine blocks of what can be converted to roller camshaft might not be comprehensive. What I've seen as the best candidate TBI block to convert to roller block will have a fuel pump block off plate bolted to the block. Once the fuel pump block off plate is removed, the holes for the fuel pump push rod should be drilled and the oil drain back hole is drilled. When I've seen the fuel pump push rod hole cast over the spider bosses were absent. I've seen one block where the spider bosses were present, but not drilled and tapped when the fuel pump push rod hole was cast over. The same block that did not have the spider bosses drilled and tapped had some clearances not machined for the lifter dog-bones, which caused the lifter dog-bones not to lay flat onto the block. So when I'm shopping / looking for a roller one piece rear main seal block in the junk yard pile of rebuildable cores, the best candidate to purchase (IMHO) is the block with a fuel pump block off plate bolted to it. Then remove the fuel pump block off plate and verify the fuel pump push rod hole and oil drain back hole are drilled and machined. If you find a light chocolate color looking oil after removing the fuel pump block off plate, it's time to look for another engine block.

    dave w

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