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I have a 1989 350 block out of a p/u that did not come stock with a roller cam. I was just wondering what had to be done with this newer bock to adapt an OEM roller cam? I've seen articles about the '86 and older blocks, didn't know if it would be easier with this newer block? Any help would be greatly appreciated!
 

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Does the engine have the OEM roller cam accessories? like the cam retainer plate holes behind the timing chain? Also does it have the spider retainer bolt bungs in the center of the lifter valley? Does the flat tappet lifters sit so low in the lifter bores you can`t see any of it except the top? If your block has these you should be good to go. However you can still look on mortec and it lists some blocks that were roller cam compatible in those years. Just write down your casting number and compare. Good Luck.
http://www.mortec.com/castnum.htm
 

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speeddemon29 said:
I have a 1989 350 block out of a p/u that did not come stock with a roller cam. I was just wondering what had to be done with this newer bock to adapt an OEM roller cam? I've seen articles about the '86 and older blocks, didn't know if it would be easier with this newer block? Any help would be greatly appreciated!
Look for the block casting number! These are 350 flat tappet blocks of the period, look for casting number 10045727, 14079287, 14088548, and 14101148. These have no provision for the OEM roller cam. These blocks can be modified to take an OEM roller set up with the following modifications:

1) Cam thrust taken with a conventional bumper, you can also use an aftermarket hydraulic roller cam like this. An aftermarket roller cam for a non-roller block uses the cam gear and chain for the flat tappet engine.

2) If using an OEM roller you need a thrust plate to take up the nose distance machined on the cam, this is done taking an OEM thrust plate and cutting the mounting ears off and breaking any rough edges. This requires that you use the OEM cam drive gears and chain for the roller cam.

3) Use roller lifters for the 4.6 liter 90 degree V6 with standard length pushrods.

4) Use the OEM dogbones to align the lifters.

5) Use a die grinder to machine proper dogbone clearances into the area around the top of the lifter bores.

6) The OEM spider is attached by drilling and tapping the mount locations thru the main oil galley. The proper way to minimize oil volume and pressure restrictions is to drill the galley 1/16th to 3/32nds oversize for it's entire length. The spider mounting positions are drilled and tapped clear thru the oil galley into the crankcase, this will pass the bolt thru the oil galley for a secure mounting of the spider. Once the spider is shimmed into the proper position to hold the dogbones, measure for that portion of the spider mounting bolts that are in the oil galley passage. On these bolts remove the threads that occupy that space inside the galley and dress the remaining end threads to insure they smoothly pick up the threaded hole on the top and bottom wall of the galley. Install the bolts with a mild strength sealer like Permatex Medium Strength blue thread locker to prevent oil leakage and loosening as the spider vibrates quite a lot.

Roller blocks may have a flat tappet cam installed but are provisioned for a roller even if using a flat tappet cam. For 350 roller tappet blocks look for casting numbers 10243880, 14011148, 14088526, and 14093638. The provisioning would be the machined surface and fastener holes for the cam thrust plate; the three bosses cast and tapped for mounting the spider on top of the main oil galley; raised and machined lifter bosses for the longer V8 roller lifter.

Watch the numbers 14101148 which is a flat tappet and 14011148 which is a roller not much of a number difference big casting difference.

Bogie
 

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Assuming your block is set up for the factory roller stuff, you'll need lifters, lifter guides, lifter guide retainer, shorter push rods, timing set (chain & sprockets), camshaft retainer plate, and all attaching hardware. GM sells all this stuff in 3 separate kits for ~$300 if you can't find them used.

Push rod kit ....PN 12371041 --contains 16 push rods.

Lifter kit ........PN 12371042 --contains 16 lifters, 8 guides, retainer, & 3 bolts.

Timing set .....PN 12371043 --contains chain, sprockets, retainer, & 5 bolts.

Search these part numbers at http://www.sdparts.com/categories/EngineComponents.aspx for details.
 
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