[tom s]

Thinking about building a alu block RA V engine for my 69 bird.Is there anything I should know before I go shopping for a IA or KRE block?I want EVERYTHING that bolts up on our stock blocks to just bolt up,stock oil pan,windage tray, valley cover, motor mounts,exhaust clear etc etc etc.Anyone with experience that has built both blocks?Tom

[mgarblik]

I have no experience with the KRE aluminum blocks. Can't say I have even looked at one disassembled. I have built multiple IA aluminum blocks, however. Tom, if you have built iron IA II's, the aluminum version is identical. So any issues you have experienced with the IA II iron should be the same with the aluminum one. Specifically: The freeze plugs are screw-in so they look a little different. The oil pan rail is extended for the registered main caps, so you will need the slightly longer oil pump drive rod and a little filler for the front of the oil pan where the timing cover goes. You can use RTV or double gasket, or make a little metal filler. The deck is extended front to rear and is wider. So slight modifications may be needed for exhaust fitment and front accessory brackets. All these things are minor and make the block much stronger for serious performance builds and more reliable. Be aware also, that the minimum finished bore will be 4.250" IMO. The one I am building now has an as delivered 4.241 bore and is pretty rough. It should finish at 4.250 with a perfect finish. If that's too big, call Frank at All Pontiac and see if a smaller bore is possible. I can not verify, but I think the KRE blocks have a more stock appearance externally, with drive-in freeze plugs and the non-extended decks. I am sure someone who has bought one can chime in on their particulars. The IA II aluminum blocks weighs 134.6 lbs. Just weighed the one I am building. That is bare block, caps and studs as delivered.

[tom s]

From what I have got so far the IA is out.Will look into the MR1A a little more.Im being told either take Xtra machining to get a finished product.I know the IA is dry deck also.Have not been able to find a V block so was thing a aftermarket Alu.Tom

[mgarblik]

Originally Posted by tom s

From what I have got so far the IA is out.Will look into the MR1A a little more.Im being told either take Xtra machining to get a finished product.I know the IA is dry deck also.Have not been able to find a V block so was thing a aftermarket Alu.Tom

I would consider ANY aftermarket block for ANY brand of engine semi-finished. A pressure test is a must. All machine dimensions need to be verified. Some casting flash removal, oil passages massaged, the usual stuff. Yes The IA II blocks need to be drilled for water. This is a great way to sell the blocks, IMO. That way you can put the water holes where you want them, based on heads used, bore size, gaskets used. Much easier than drilling, tapping, and plugging unwanted or holes that are too large. Good luck with the build.

[77 TRASHCAN]

Mike,
What is the max bore size on a IA aluminum block?
Is the aluminum block sleeved, and you are honing sleeves?

[mgarblik]

Yes the block has the sleeves installed and ready to hone. If your going for a large bore size, you would bore it then hone. I recommend a call to All Pontiac to determine the rough size of the bore you want it delivered with. Honestly don't know if you can choose a given rough bore. The one I am doing now has a "standard rough bore" at 4.241. Which will be perfect for a 4.250 finish. They advertise a 4.350" bore is their maximum desired finished bore. Torque plate mandatory, IMO.