Long Rod 300 Build

Discussion in 'Small Block Tech' started by Duffey, Mar 6, 2018.

  1. Jim Nichols

    Jim Nichols Well-Known Member

    Derek, I assumed he was back to using the 340 crank because of piston choice? The only clearance issues Chris had was the first two rods hit the shallow front of the oil pan and last two hit the windage tray. Dimpled the pan and put washers between the windage tray. Plenty of cam clearance with the Crower Stage 3 cam. I talked to him today and he said he was going to Dyno tune this spring with no air filter and open headers to see what he could get compared to the air and exhaust restriction.
     
    Last edited: Mar 12, 2018
    300sbb_overkill likes this.
  2. 300sbb_overkill

    300sbb_overkill Well-Known Member

    Those rods will still be fine in a sbb 300, the only difference between a sbb 300 and a sbb 350 is basically the deck height is taller. They both have the same cam to crank centerline actually is the same from the 215 all the way to the sbb 350.

    If he's going to use the 340 crank, the 340 rods will be lighter than those cap screw rods and will handle as much power as even ported 300/340 heads can throw at them N/A. With either set it is the RPM that needs to stay in check.
     
  3. Duffey

    Duffey Well-Known Member

    Yes my clearance question was in regard to the 340 crank. I haven't decided which crank to use until I pull the 340 and make sure the crank is useable.

    Good to know they shouldn't be a problem, the guy usually doesn't sell to individuals so I was worried about rocking the boat by requesting exchanges. Also, when I asked about him doing ARPs before resize and he had already shipped, he mentioned he didn't know when/if he would see more cores.

    I figured going with the cap screw rods was a case of better safe than sorry, plus the I'm pretty sure the price would have been the same either way.
     
  4. Jim Blackwood

    Jim Blackwood Well-Known Member

    Should be OK but test fit with your cam in the block and check clearance to the rear cam lobes. The upper outside shoulders of the rods are what will be close.

    All SBB cams are "reduced base circle" cams. It's the only way to get more lift out of them. So if one clears, they all should clear.

    Jim
     
  5. Jim Nichols

    Jim Nichols Well-Known Member

    Duffey, You can take quite a bit of weight off those huge balancing pads. I sand the casting flash off the beams and shot peen too. Similar to this picture Sean has. Looks like a couple got wet/flash rust. capscrew.jpg
     
  6. Duffey

    Duffey Well-Known Member

    Oh wow! Those look amazing! I'm assuming I should wait to do any grinding until I know how my balance situation is going to pan out? Wouldn't want to remove too much right?

    I'm trying to find my scale to weigh the difference, though Derek seems pretty confident there is a 200 gram difference. But maybe that's with the non cap screw long rods?
     
  7. Jim Nichols

    Jim Nichols Well-Known Member

    The one you show I would leave that much on the bottom and take about half off the top on all of them. Sand lengthwise on the beam and grind slow to not build up too much heat on the pads. You have to remember the early ones you show are 300 rods. Does the 340 have early rods to compare?
     
  8. Duffey

    Duffey Well-Known Member

    Yeah I should be able to compare a 340 rod once I pull the motor.
     
  9. Duffey

    Duffey Well-Known Member

    Here are the weights. Both sets had the same conditions on the same Wal-Mart food scale (but I find it to be quite accurate). The weight is in grams.

    350 Cap Screw Rods
    655
    660
    654
    654
    660
    656
    661
    659
    Average-657.375

    300 Rods
    591
    590
    593
    575
    591
    590
    592
    592
    Average 589.25

    So it works out to an average difference of 68.125 grams (.150lbs) per rod. That means you add 1.2lbs to your rotating assembly when you go to the 350 cap screw rods, in case you ever wondered.
     
  10. Jim Nichols

    Jim Nichols Well-Known Member

    Duffey, That is interesting. That means the longer 340 rods are probably about half as as much difference. There is a large weight on each side of the beam. There are some You Tube videos on balancing the rods and pistons and making a simple fixture for pressing the pins in too.
     
  11. 8ad-f85

    8ad-f85 Well-Known Member

    You mean fitting them with heat, right?
     
  12. Jim Nichols

    Jim Nichols Well-Known Member

    Yep, Mapp torch for small end of rod, frozen pin.

     
  13. 300sbb_overkill

    300sbb_overkill Well-Known Member

    I said there was around a 200 gram weight difference between the cap screw rods and the one in the link Jim B. posted that weighed 480 grams.

    [​IMG]
     
  14. Jim Blackwood

    Jim Blackwood Well-Known Member

    I noticed those rods in that link are sold without the capscrews. That will add back in a little weight. I'm not sure how much, just guessing it'll be in the 50-75 gram range.

    Jim
     
  15. Duffey

    Duffey Well-Known Member

    So I know I want the v6 oil pickup, but any suggestions on where to get a good one at a good price? Also, what is the consensus on through pushrod vs shaft oiling? I need to figure out whether I need to plug the holes in the block.
     
  16. Jim Nichols

    Jim Nichols Well-Known Member

    Duffey, Chris has went 3 years so far with the through the pushrod oiling. I think it is better. Buick changed over also. He used the 350 lifters and Smith Bro's pushrods. He also used the Crower cam saver lifters with the Crower cam. I've got some ideas for better rockers too. V6 pickup could be obtained from NAPA or other auto parts store.
     
    Last edited: Mar 19, 2018
  17. Jim Blackwood

    Jim Blackwood Well-Known Member

    TAPerformance also carries the V6 pickup. If the front cover is coming off you should enlarge the pickup galley in the block. If not I wouldn't worry about it. Pushrod oiling seems to work fine but I have always wondered if the rocker bushings are getting enough oil. I don't see any good reason to change it over and have run lots of shaft oiled engines. Either way seems to be fine. Could be pushrod oiling allowed cheaper rockers, I can see that being a good reason for Buick to change it. I think some of the later 350 head gaskets may not have a hole for the oil. That'd be the simple way to block it off.

    Jim
     
  18. Jim Nichols

    Jim Nichols Well-Known Member

    I don't know if the 350 head gaskets would work. Water jacket is a little different. I've used lead shot under the rocker stand hole. Chris used a shim for the taller Chevy V6 valves for proper geometry to block the oiling holes.
     
  19. Duffey

    Duffey Well-Known Member

    Looks like I can get a Sealed Power brand pickup for $14 shipped off eBay. All the local parts stored (NAPA included) wanted to know make/model/application, which is a little annoying to deal with.

    I have the pickup galley at 1/2 inch right now, 9/16 kinda worries me so I think I will just contour the portion where the pickup bolts on to whatever the pickup size ends up being. Hmmm, maybe sticking with the shaft oiling will be more intuitive? What are your ideas for better rockers?
     
  20. Jim Nichols

    Jim Nichols Well-Known Member

    I know a guy that is having a set made from small block Mopar at Rocker Arms Unlimited. Around $400. He hasn't got them yet. They used to use 2 sets of Volvo B20 4 cylinder steel adjustable rockers bushed to fit stock shaft and 3/8" cup style adjusters. The larger adjuster is set in farther to convert 1.5 to 1.6 ratio. I have an idea to use new stands and the later 350 steel rockers with new same diameter shaft as 350. Buick 231 oddfire V6 tubular pushrod(V8 set same as 61-66 326,389, 421 Pontiac). Center of shaft .030 lower than stock. The V6 pushrods are .030 lower than stock. I'll play around with that when I retire in 21 months. I like the Burton/Hot Rod Mag bar and stud with Chevy rockers too as long as you use 7/16" studs.
     

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