I am starting to wonder if my car actually has a solid lifter cam. When you first start it from cold, there is virtually no valvetrain noise. Once it warms up it rattles like crazy. I guess I would expect it to be louder cold and quiet down as metal parts expand. Could this be a plugged cam bearing issue? It does seem a little louder on the drivers side. I have a new cam ready to go in next week. I was planning to change primarily so get away from having to adjust the valves all of the time. It is also so radical that the power brakes are affected. On top of all that, I have no clue what the cam specs are. Changing it will at least give me an idea of what I am working with. I am asking because I saw a reference to noisy Buick valetrains in another thread. What's the scoop?
Need a little more history on your engine, how many miles are on it? What kind of oil pressure are you reading (both cold and hot)? Other internal parts if not stock? You say you want to get away from adjusting valves, but if you have the stock rocker assy there is no adjustment (now if you have aftermarket roller rockers that's a different story). If this is a high milage engine or an engine that you don't know the history on then I can't recommend changing the cam without installing new cam bearings. In regards to the noisy lifter post, most of those are probably mine. I have the older version oiling system which will use different lifters than your engine, there's been a lot less trouble with the style you would be using. Is this car going to be a street or strip car? You say you have a new cam already, what cam is it? If your getting noise when the engine is warm it sounds like your oiling system is a bit weak, you really need to get a mechanical guage on it to see what kinda pressure you have. Good Luck.
Thanks Len, Here is what I was told. The engine is supposedly from a '70 Riv. The PO told me that the "SF" code on the heads confirmed this. I think the engine has been in this car for quite some time, 5-10 years, and about 20k miles. I don't know if it was rebuilt before installation but, they did add the cam, performer intake, headers(look like VG quality)and an HEI. The car has a pretty good lope and very little vacuum. I yanked the 2" NAPA exhaust off and installed a Flowmaster "American Thunder" system. This really seemed to wake up the car. I have installed a mech oil pressure and temp gauges. I show ~60psi cold and ~20 psi at warm idle. Seemed pretty healthy to me. What should I have? I have a Postons GS113 cam and their HP cam bearings. I am going to run Rhoads on the intakes and reg hyd lifter on the exhausts. I haven't had the valve covers off yet to see what I have for rockers. Judging by some of the other work, I would say that adjustables are unlikely. I would bet they are stock. If it is the existing cam bearings, then It sounds like my new cam/bearings will solve the problem. I wish that I knew more about the heads. I am betting that the cam I have now is way too much for the heads flow. I was hoping that the 113 would be a better choice. I also do not know the CR, that was another reason I chose the 113, Postons claims it works well with high or low compression engines. Once I tear into it next week, I will collect some casting numbers. Is there a good source to determine what I have?
I pulled the valve cover. The rockers are stock. I double checked the oil pressures I noted, they are correct. 1000 rpm and 30 psi pretty much eliminates the noise. I also purchased the high pressure/high volume oil pump. Looks like I have my work cut out for me I took the casting number off the head. I will see what I can find. (BTW the number is 1231786)
oh, i'd be careful with the high volume pump. It tends to accelerate cam bearing failure. GO to www.taperformance.com and read about it. they try to swing people away from it. just a little bit of info for ya.
Yeah, if you've got 60psi/20psi your in real good shape, and I agree with the above about staying away from the HP/HV pump, just get a booster plate and adjustable regulator and you'll be lookin good. I've heard of alot of guy's using the 113 cam and loving it, though I think your still gonna have a pretty rough idle with it, I'm sure someone hear on the site using that cam can give you some better insight to it. I don't know anything about the Poston cam bearings,(I'm using the TA dual grooves). I beleive the SF code you mentioned will be on the block not the heads, should be on the deck surface in between the #5 and #7 cylinders, you can see it with the head installed. You can chase down the head casting numbers on the Atlanta Buicks site I believe, I don't have the link handy. Try some of the simple things to elimate the noise, run a bottle of Marvins Mystery Oil for a couple weeks, try stepping up one weight in oil, or running some Seafoam in the crankcase to clean it up, you may get lucky, and all that stuff is cheap and easy to try. Regardless of the results of the above, with the little you know of the engines past I would change the cam bearings when you do the cam install, (and be sure to degree the cam when you put it in).
cam/lifter problems http://www.atlantabuick.com/CastingNumbers.htm This is the link. ------------------------------------------------------- Mac
I'm curious how your going to change the cam bearings? Do you have the tool to R&R them?:jd: Not fun w/ block in car I'd guess, but I dunno as I've only tried in a machine shop. Fill me in on the details, please.
Looks like the correct casting number for 1970, and they may even be Stg1's, though you would have to pull them to verify that.
You will like the GS113, it pulls hard from 2200 up. It sounds to me like you have worn or bad lifters(not that this is uncommon with a buick), and mabye worn rocker ams. I would check the cam bearings but if there ok just put in new lifters and new rockers if needed.
Both the engine and trans are coming out this week. My buddy is a mechanic and we are pulling it at his shop and putting the engine on a stand. The cam bearing tool will be borrowed from a local engine building shop. I am now really tempted to pull the heads and see what I have for valves. Beyond my curiosity though, it doesn't make much sense unless I am going to have them ported, something I had not planned on right now. This car is mostly my wifes toy. It really doesn't need to be a 12 second car. My plan was to make a few changes and run it for a while. I guess if I was really serious about it, I would haul it to Tri Shield and drive out with 5-600 hp. The trans was really the bigger focus this time. It is leaking from several places right now. It is getting a rebuild and switch pitch conversion (3000). That and a governor adjustment should allow my wife to pull it to the line, leave it in drive and turn high 12's or low 13's. If that gets her hooked, I'll get serious with the engine. If the rest of the engine is stock, what CR did the '70 Riv have? Thanks for all the help guys!
TA has some options for the rockers I think around $200 gets you a stronger stock type, $600 or so for their best roller rockers. And with the Rhoads on the intake valves, I think you will like the idle.:TU:
Take a rocker arm shaft off releasing tension EQUALLY FROM ALL 4 BOLTS!! Pop a couple of the nylon buttons off, and check to see if the shafts are worn, or rockers. The excessive clearance here is what usually makes the noise. Either get the upgraded Chrome Moly "stock type" replacement shafts and rockers, or roller rocker assys.:Brow: (If needed,new nylon buttons are available from your parts store seperately, and just pound in with a hammer and 1/2" ext.!) :bglasses:
With the 69cc head I would imagine the advertised CR was probably still the same 10.2 to 1 that the 400/430 had, I'm not real up on the 70 455.
