J0hn_J0hn08

iTrader: (2)

I recently purchased a 350 block that is equipped with roller provisions but has a flat tappet cam installed. They came like this from GM on the late 80, early 90 trucks as far as i know. The block is casting number 14093638. "638" block

I want to convert the block to a full on roller, i removed the intake and i saw the holes in the center for the spider.

Currently as is this block is perfect for my 86 Iroc since it is fully drilled for a mechanical fuel pump, but i want to start gathering the parts for a full roller set up.

What all would i need for this conversion?

I know the ovbious like hydraulic roller lifters and a roller cam with the lobe for a mech pump for starters but what else? Any help on this apreciated.

redneckjoe

youll need different length pushrods off the top of my head. i wonder about the dizzy gear?

J0hn_J0hn08

iTrader: (2)

i plan on keeping the car carbed, and running a HEI dizzy. Would i still need to worry about the dizzy gear?

Does anybody make a kit for this conversion?

ASE doc

Good roller cams are made with an iron dist gear pressed on so they can be used with factory steel distributor gears. You will need to find the "spider" and "eyeglasses" that retain the lifters and prevent them rotating and the cam retainer that holds the cam in place in the block.

Here in Portland we have Engine Rebuilders Supply which stocks piles of factory engine pieces like these for cheap. I would imagine there is someone in your area who would have them.

As far as I remember, the pushrod length is the same if using factory roller lifters but you'll need new pushrods anyway to go with the new lifters. Just use the factory length pushrods for the 87 and up Z28/IROC engines.

redneckjoe

comp cams lists the roller block pushrods at 7.195 inches, 1987 up with o.e. hydraulic roller. 7.794 inches for 1955 up flat tappet. of course this is with factory roller lifters. ive seen the difference first hand, just wanted to make sure i had my facts straight. all good advice though. should be a fairly easy swap.

J0hn_J0hn08

iTrader: (2)

Thanks for the detailed replies.

i spent all day yesterday researching and i came up with the following parts ill need

GM 12371042 hydraulic roller lifter kit includes lifters, spyder tray and lifter retainers for 192.00

GM 10088128 Cam retainer + bolts 6.95

Summit CLO-9-1145 cloyes timing chain for roller cam 52.88

GM-10046173 7.122 .60 heat treated pushrods for non self aligning rockers with guideplates 120.00 for set or GM 10241740 for set without guideplates

Now im wondering what would be a good cam choice to run with the 14102198 heads. Im considering the Regular Lt4 cam, how well would that work with stock TBI heads on my carb set up? Not looking for anything extreme i really just want to get the roller set up going and worry about performance later.

i read somewhere some thirdgens came with roller cams that included the fuel pump lobe. Anyone know about this ?

Would the 7.122 pushrods work well?

ASE doc

As I remember, the roller cams Ive worked with had the fuel pump lobe. Just look for it before you install the cam. I think the LT4 cam may be the upper limit for your stock TBI heads. It should work okay. I honestly dont remember the pushrod lengths. You can measure for yourself to be sure. Using a light spring from the hardware store, enough tension to hold the valve closed, soft enough to compress by hand, replace one valve spring and install the rocker with one of the pushrods you have, setting the lash at zero with valve fully closed. Use a straight edge or an angle finder to check the angle between the rocker tip and the pushrod seat of the rocker. Now turn the engine so that the valve is fully open. Recheck the angle between the tip and pushrod seat. The halfway point between the two angles should be a 90degree right angle to the valve stem. At this point you will achieve optimum valve train action.

Of course for best results, install roller rockers. Comp Cams Gold Race or Pro Comp, or any narrow body rocker, will fit your center bolt heads.