Need some advice for rebuilding 77 350 please

Hi everyone,

I have a 1977 Buick 350 that I am putting into a stripped down 73 Buick GS. It will be used with a M-21 4-speed.

Long story short, I bought a TA 212 cam and 1970 Buick 350 4-barrel intake for it since it came with a 2-bbl. I wanted to get a little more performance out of it before I put the engine in the car so my plan was to swap the cam, with new lifters, install the new intake and carb and go.

As I went to take out the original camshaft I had an extremely hard time getting it out. Made sure it wasn't hitting the crank, etc. it wouldn't spin easily by hand when I removed the timing chain as well. Note the engine had 64,000 miles on it and ran great. Started right up, no weird sounds or anything.

I finally got the cam out after some persuasion and put the journals against a straight rod. Well, there is a large gap between the front journals and the rear (towards the transmission). It appears the the front three journals are out of line with the rear two. Not what I was hoping to find.

I lubed up the new cam to see if I could get it to go in. The rear journal on the cam went into the front bearing with no problem but the cam got stuck on the second one.

So now reality sets in, this isn't going to be an easy swap like I planned. Just my luck....

I am on a strict budget, in college and need to get this engine completed because I have larger projects. Just so happens I have brand new cam bearings I bought for one of my 455s for future use, but they are the same for a 350.

Now I know I have to tear the bottom end apart to get these installed so since this is the case, I would like to increase the compression ratio on this engine. I know these 77 engines are at 8:1 or lower. My goal is to get an engine like the 70 Gran Sports had. 10.25:1 compression.

So my questions are the following, and I'm sure ill have more along the way of the rebuild:

Is it cheaper to get the heads shaved down in order to achieve this compression ratio, or should I look for a new set of pistons?

I know the later rods are better so I will stick with them. I don't have the money to get the heads ported so they will stay stock, at least for now. I do however have a full set of NOS 350 valves (I think for intake and exhaust). If this is the case obviously I will install these as a valve job is easy to do.

Also how about head bolts and rod bolts? For a simple rebuild like this what should I look for in order to save money but also feel confident that I won't have any issues for longevity.

Any help is appreciated and thanks for taking the time to read this.:beer

 

You say the journels are out of line, is that the bare journel or with the bearings?
Buick engines are very tough on cam bearings. I'll bet yours are grooved and/or partly melted causing the misalignment.
Bad cam bearings are also THE major culprit in low oil pressure in these engines.

You can mill the heads to get the compression up but you are better off cutting the block as I've mentioned several times in other posts. Why would you want to weaken the already crack prone head?
There are NO off the shelf pistons that will give you the advertised compression when it's .060"-.100" down the hole.

Steve

 

Steve,

Thanks for the reply. I was speaking about the bare journel so just the camshaft laying down by itself. Ill try to take a picture, there is a noticeable difference, and I was shocked to see this.

The cm bearings are still in the engine and you are right, they do not look great.


Is there a specific amount the block should be milled to achieve a compression ratio around 10:1?

I'm certain this engine has never been taken apart but will verify the pistons in it as soon as I take the heads off.

Thanks again.

 

I have a set of 70 rods and pistons hi comp from my SP engine.I also have 6 3.0 pistons(I'm sure you could find 2 more). Either will get your compression up. I wouldn't bother with putting new valves in it.get lapping compound and clean them up that way. You said it ran fine don't mess with it unless you are going 100% .n

 

You should have no problem changing the cam bearings with teh bottom end together. Without any machine work you should be able to get close to 10:1 using the 3.0 V6 Flat top pistons. I would consider trying to find some 68-71 heads as the 77 versions will put you down on HP big time compared to the early heads.

I have seen as high as 11:1 static compression with block and head milling and 8:1 pistons so it can be done. Here is a 11 second quarter mile combo with the 8:1 pistons:

Stock 1973 block and heads. The rotating assembly is all stock parts inspected and balanced. I had a larger 5/8" oil pick tube installed along with a melling oil pump rebuild kit. The deck was zeroed. KB118 cam was degreed in. The heads used stock valves and rocker arms but have been ported, polished with the heat crossover filled. The intake is stock with the exception of being port matched. Both the heads and intake were milled for a static compression of 11:1, 8:1 dynamic compression, stock bottom end with milled deck, Modded Holley 4175 carb It was flowing around 800 CFM.

- KB118 camshaft
LSA 118 / ICL 113
ADV. 276 /295
ACT.@ .50 228 / 247
int .487 / exh. 475

 

Sean, is it worth it for me to try and do the cam bearings myself or do you think a machine shop would do it with the bottom end still together?

So the 3.0 V6 pistons will fit directly in the 350? No boring out the cylinders?

If I don't have to pull the bottom end apart, I would really rather not due to my budget and time for getting this engine in the car.

Any idea how much should be shaved off the heads and intake in order to achive a high compression ratio around 10:1 - 11:1?
Also are the 77 heads still worse in Performance after port work is done compared to the earlier heads with port work? If the HP loss from the later heads can be compensated for by machine work, I can wait to do that and just get them milled currently.
Thanks!

 

I can't comment on your cam bearing situation, but you mentioned that you're using an M21 4 speed. What is your rear differential gear ratio?

 

If you mill the block to zero deck you will achieve the advertised CR only. To verify any of this you need to CC the piston dish and chamber size. Any milling of the head or block much more than about .040" will probably need shorter pushrods. Again you need to measure and verify.
.040" cut anywhere is roughly equal to 1 point compression gain on the 350.
The V6 pistons may have a smaller dish or are flat tops to increase the compression but are still just cheap cast pistons so beware.


If you are truly looking to do a budget build cut the heads .040", install TA grooved cam bearings installed per the instructions and a Crower level 2 cam PN 50257.

 

I know it is a budget build so I suggest one of the following:

1. Mill the heads till you get 9:1 and use a TA 212 cam and keep the bottom end together and not modified. This would run on regular fuel and not require premium.

2. Swap in 3.0 pistons and use a master rebuild kit from Northern Auto Parts and then you could use any cam you want to as the compression would be nice and high although premium fuel would be needed. No mods needed for the 3.0 pistons, they swap in but you would want to hone the cylinders... it is one of those things where it spirals out of control once you start rebuilding as you are better to do it right once then do it again later and end up paying more in total. sometimes a re-ring and new bearing rebuild works fine, other times it is a waste of money.

In the end, regardless of the compression ratio the 77 heads would be a bottle neck... If you found a set of early heads it would make more power at 8.5:1 then the later heads with high compression I would bet.

 

Just a reminder, the steel shin 20 thou thick head gaskets ony work on the 68-71 heads, but those heads can be used on any 68-81 block.

 

Sean, thanks again. I appreciate everyone's input.

Option 1 seems the most reasonable and for a "budget" build. I am going to be honest and say I do not have a direct amount of money I know I can/will spend. That figure will be different for me next month, but this thread has let me look at the different options available for this 350 and now I am able to compare time vs money vs horsepower a little bit better, and that is what I was looking to do.

Thanks for everyone's help.


To get back on track though, here's is what it looks like I will do:

Try to find a set of 68-71 heads, shave them down to get about 9:1. Will I need adjustable push rods if I go this route?

Sean, you said that I can do the cam bearing without taking the bottom end apart? If I put the engine on an engine stand and take the oil pan off I will have enough room inside the block to get to all the cam bearings with the rods still attached to the crank?

 

Anthony,

Let me see if I can talk to my partner (Dad lol) into parting out one of our 350s. We have a 68 and a 71 laying around and I can get you a set of heads cheap.

 

Thanks Louie!

 

I can answer this... .060 off the block and the intake was cut to line the runners back up with the heads. Yea adjustable pushrods were used. No clearance issues.

 

The info that you quoted from me above came from an e-mail from Maurice who just joined the thread and added the info about how much he milled the block, that was his build and I was collecting info for my book which is why I had the info.

I have never installed cam bearings with the short block together however people have done it with the engine in the car and short block together so it is possible and I am sure easier with the engine out.

Any time you remove over 30 or 40 thou off the heads or block then either custom length or adjustable pushrods are needed.

As Maurice says he took 60 thou off the block which is the typical amount it takes to zero deck the pistons in these engines.

The build that he has done is very similar to the NHRA builds that Bob Gere, and other guys are running. They use the low comp pistons, mill the heads to 48 CC, and with some tricks they run mid 11s in the quarter with no head porting and their static compression ratio is about 11:1:

http://www.v8buick.com/showthread.php?215851-L-SA-at-the-Nats

 

Unless you need to for class rules get right pistons for compression spending just as much either way more with all the machine work.

 

I've installed cam bearings with the engine in the car a few times. Its not the easiest thing, it requires ALOT of dexterity, AND a cam bearing tool. All the bearings EXCEPT THE REAR ONE can be done. You have to weasle the bearings in and out of the openings in the lifter valley AND load the bearing onto the tool, THEN hold the large nut on the end of the expanding mandrel while you turn the handle of the tool to expand the mandrel to hold the bearing, THEN make sure you have the bearing's oil holes positioned properly before driving the new bearing. Sometimes, the casting flash in the openings in the lifter valley wont let you weasle the bearings in and out, may want to check that before trying this.

 

Last post said they install while engine is in car. So the are believing engine is in car.

 

If it's on the stand and you need cam bearings, you are going to have to pull it apart and have someone knowledgeable install them if you don't know how.. Mark everyting so you know EXACTLY how to put it back together.

I would install new bearings of the same size if they look worn. Some say not to?? Not sure why. Cheap..

Geeze.. Can you get the pistons out, or is the ridge too big.. Once it's on the stand and you start taking it apart it becomes a whole different game..

Maybe you can pull the crank ( or let the machine shop), leave the pistons in the bore, get the shop to install the new cam bearings, shove the 212 cam in and make sure it's good, take apart the good heads that you have, port them yourself by learning from this site, err on the conservative side, but certainly cut down (smooth) the valve shrouds, have the shop check them and mill them .060 along with the intake to match, and put it all back together.. It's going to cost more to ship some dead heads to you than it will to make yours pretty good..

OH.. If the crank comes out you need to install a neoprene rear main seal. There is also one that is supposed to be better that that. Can't remember who sells it..

If you want to stay on a budget you have to stay focused..


OK guys.. Shoot that apart..

 

I should have said "I bet that the rear bearing can be installed front the top of the engine". I will have a look in a few days when I have a chance and see if I can fit a spare bearing in from the top. Either way like you said it is not hard or time consuming to remove the crank and like Jay says the pistons could stay in the holes and just remove the crank to make it easier to install the bearings from the bottom instead of messing around from the top....

When the engine is out of the car there is little reason to try to install the bearings without removing the crank, I think we can all agree on that... I just have the shop install the grooved TA bearings when they are doing the machine work so I have never had to install bearings myself and never bothered to buy the tool.

I agree with Jay about doing the rear main seal and I will add some tips on that thread:

http://www.v8buick.com/showthread.php?115596-Rear-Main-Seal-Replacement-Instructions&highlight=alive