Hi All, I was attempting to just swap out my stock cam to a TA212 and found out that some of the bearings were shot. After doing some research, I found that the right way to install new cam bearings is by pulling the engine. Now that I have the engine out and in deeper that I anticipated, I'm looking for some suggestions on what items I should upgrade or block work to have done while it's open? Trying not to break the bank on upgrades, just want to make the car fun! Thanks for the help in advance!
You’re going to be taking the whole engine apart, as cam bearings get pressed in before the crank is installed. If oil pressure was good, I’d just replace rod and mains with same size bearings. While block is at machine shop getting cam bearings installed, have them hone the cylinders for new rings. Oh hell, cut the crank, order custom 11 to 1 pistons, bore it .030 forged rods, roller cam, roller rockers, etc.
Budget rebuild...hone blk, polish rod & main journals, New rod & main bearings, dual groove cam bearings, gaskets, valve job if needed, timing chainset, cam & lifters, check rocker arms & shafts, & paint & re-assemble it. It'll run another 50k+ miles. Unless you want 425 hp or more, open wallet.
Personally, I would advance cam 4 degrees . Get a bit more converter and headers. The 212 flows best with headers. More compression will wake this engine up even with stock cam. But that requires pistons. And choices are few and forged are pricey but are best choice. . But you are already about at that point anyway. You can mill block or heads , but you only get about.5-.8 depending on how much you mill block or head. Don’t forget a distributor recurve kit and to richen up carb a bit. What year engine and model?
Thanks for your input. What oil pressure should I be looking for at idle, I've seen different numbers?
This definitely sounds like the budget build I was thinking of! I had everything accounted for except the valve job. Anything in particular I should be looking for to make that decision?
I went through this about 3 years ago with my 71 350. It took 2 full years to get the machine work because of COVID. I had the deck milled .020" and the heads shaved to 54cc. With a standard .040" head gasket it makes 9.0:1 compression. I also opted for the TA 212 cam too. The double groove cam bearings will help your oil pressure. I drilled the block oil pickup passage to 1/2" and installed the larger oil pickup. With a good oil pump it should hold great oil pressure. Mine is at least 30PSI hot idle and comes up with any RPM. You can add a booster plate if it is low. You should shoot for at least 20PSI hot idle and at least 10PSI per 1,000 RPM. 350s are not hard on the bores so oversize boring isn't often needed. A good hone job fixed mine up with standard bores and the original pistons. The crank stayed standard with a polish and new bearings. Heads just got a good cleanup, fresh valve seals. I had mine machined for the smaller, positive seals. Also, a fresh set of Stage 1 350 springs. My 91K mile rocker arm shafts, timing chain, cam and lifters were totally worn out. Everything was replaced with standard replacement parts. A set of Hooker headers and a new 2.5" dual exhaust helped too.
If you have 10 lbs hot idle in gear, HOT meaning after a long drive on the highway, 20 mins or more. HOT does not mean idling in the driveway, the coolant will get warm, but oil needs engine work to get up to temp. If you have 10 lbs hot idle after a run on the highway and it comes up as soon as you give it throttle, you’re fine. Buicks are notorious for lower idle oil pressure than the majority of other engines. 5 pounds, 10, 15, 20 at idle is fine, as long as it rises with rpm. You could idle with 2 lbs, there’s no load on the engine.
Good, then you don't even need to take your oil pump apart..... Pop a few springs off and wiggle the valve to see how sloppy they fit in guide. You might need a valve job, with liners installed.
Buy those iron heads off jimbuick for 1k. They have TA valves, springs, ported, probably shaved and guides installed. Sell yours for $200. No waiting for machine work.
The first thing you do is the oil mods especially if you plan on any hot rodding at all, then it will last. 50 lbs @ 3000 rpm 10 at idle is ok
The 72 has just under 8.2 compression . So an increase Will obviously make cam more effective. the distributor in 72 is kinda short on full timing. So a different distributor with a recurve or send to Everyday Performance for a rebuild with points conversion would be a good option. But it will work for now. With fresh cam bearings I would think you should see 15-20 psi hot oil pressure. Which is good This isn’t a bad upgrade in converters . https://www.jegs.com/i/Allstar-Performance/049/ALL26906/10002/-1 And mild since most people are afraid of some real convertor I think this is what I got https://www.jegs.com/i/JEGS/555/60400/10002/-1 but I am running a ta 310 cam and 9.8 compression with a 3.42 rear end eBay has used 3.08 and 3.42 gears with shims and bearings. Either would kick up the fun factor on your final setup . But big issue is compression. More will make the difference , the silvolite 1734 is about 9.6 , the 1736 is about 8.7 for cast cheaper pistons. And sets of these pistons are 6 so order the 2 extra if you choose that
Larry just posted this in another thread. Is valid for you also. Notice the full timing on 350 distributor 12-16 at 3000. Add 4 degrees of initial timing , that’s 20 mechanical advance. This engine with that cam will want 30-34 degrees. Even with 12 initial advance that’s still 24-28 degrees. So a distributor upgrade would be beneficial.
