[Steve C.]

We have another situation that has cropped with our IA II block (blk #17), this one deals with the link bar on my solid roller lifters making contact with the lifter bore pad on the block.
It happens when the roller is on the base circle of the cam.

These lifters previously worked fine in my factory 400 block. They are Crower Hi-seat offset roller lifters (0.200 pushrod offset). They are a custom lifter, part number 66299, and are basicly the same as Hi-seat p/n 66275 for the small block Chevy except for the lift bar and oiling. The a Hi-seat design allows for a shorter 7.900 pushrod length. Plus they are being used in conjunction with 0.170 offset rocker arms on a shaft system.

Prior to these piticular lifters we used Isky 0.150 offset small block Chevy lifters part number 1241-LO-150 with the tie bar set up for the Pontiac. These lifters also worked in my factory 400 block but their lift bar also makes contact with the IA II block.

To check the situation we tried regular Crower PONTIAC solid roller lifters part number 66260, these are standard with no offset. These barely cleared the block.

Thinking there might be a issue with the incorrect base circle on the cam we pulled it out and tried a previousy used Ultradyne solid roller. Same situation, the tie bars hit the block. In fact on the second cam the base circle was about 0.010 smaller than the first and with this second cam the standard Pontiac solid roller lifters will now hit the block.

At this point I didn't want to make any changes in parts .... the lifters were $525 and the short pushrods were another $230. So we machined a groove in the lifter bore pads on the block to let the tie bars clear. With a 0.070 deep groove the tie bars did not clear, the final cut ended up at 0.100 deep.

Bummer.... just more additional expense pased on to me. Plus I have one pissed off machiniest with this and other time consuming issues he has had to deal with on the block.

With this all happening I'd like to hear from others as to what brand solid roller lifters they have used on their IA II block and if they have incountered a similar situation.