I want to try my 289 heads on the 302 I have in the car now, before I spend the money on a new engine.. It has great oil pressure and runs very good... What is the best way to prep the surfaces ? and what is a good choice for the gasket ? My block is a stock bore, the 289 heads have screw in studs roller tip rockers and good springs w/dampers and guide plates Note: The reason I want to try this is because my old 74 heads have a lot of valve chatter... these are positive stop with no adjustment.. I will use ARP head bolts.. I have a new set of stock push rods, and will not touch or tamper with the lifters that are in there now because they have been with that cam since the rebuild... What else do I need ?
First.. make damned sure your blocks water level is down enough.. or the stuffed rags/paper towels will get soggy and hold debri.. and the vacuum will make a mess when you get too close to any open water passages. Spin the engine until at least 2 adjacent cylinders are sufficiently below deck and stuff rags/paper towels to work on half the deck at a time. Usually best to clean oil/antifreeze off the bores so they'll stay cleaner/easier to vacuum/re-oil once finished. A cool trick an old friend showed me, although I've never done it since I'm always in such a hurry with jobs like that and rags are pretty handy.. involves using paper towels or rags underneath cardboard discs cut to slightly larger diameter than the bore with small carriage bolt punched through the center for easy removal. Cuts down on the cleanup and he doesn't need to push them very far down the bore. He tends to remind me how smart his invention is when I'm delicately trying to vacuum and coax debri off the bore walls. Which always leads to me asking why "he's too damned cheap to not just use Styrofoam? I may be hard headed.. but yer cheap!" lol Another thing that works well is to stuff rags/paper towels in every hole possible and just cut material towards the stuffing with the smaller scraper. Depending on amount of remaining gasket material.. I usually start with a freshly bladed 4" inch wallpaper scraper(leaves larger crumbs/less mess).. but any old 1.5" window scraper with a few fresh razor blade will do. Just takes a lot longer and sometimes your hand starts cramping while you're intensely focused on trying not to slice yourself up in the process. lol Then just abrade the surface with 100-120 grit sandpaper to remove the remaining material. Air tools or elbow grease works better than electric because you can control the rate of residual removal/reduce dust and flying debri. Follow that with several cleaning stages using continuously fresh towels with whatever you may have laying around.. laquer thinner, acetone, or denatured alcohol work well with no greasy byproducts. After that you need the thinnest head gasket you can possibly find that's still within your budget. Also find one with the smallest .060 bore diameter too. Reducing quench to the minimum possible is worth even more than the compression increase gained by doing it. Less required spark lead lets you know things are better and you did good by spending money here. Also.. early pushrods that are hardened for proper contact wear with the 289 heads guide slots would be best.. but I'll quickly admit to using the non-hardened versions a few times. To me.. it seems that due to the fairly large contact area of the guides and being oiled well enough.. wear wasn't a huge deal after 15-20 thousand OFTEN HARD miles. They WILL wear with distinct patterns and small ridges though.. so base it on your service needs. With decent cams in these little high revving motors.. I used to often tease the Mazda boys about.. "zoom zoom my ass!".
