MDchanic

Greetings, all.

I have been hanging around these esteemed forums for a little while now, and have been able to both offer some advice (a bit of it good) and to glean some valuable information. The time is coming to do a bit of motor work, so I hope to be able to get some realistic, practical advice from our experienced members about this upcoming project.

First some background and context: I have owned and enjoyed a few Oldsmobiles in the past, but had not had one for a number of years, until last fall when I chanced to purchase an intact, registered, on-the-road '73 Delta convertible for $900. Rust is under control, paint isn't nightmarish, but needs to be redone (I expect to be using rattle cans), top is all there, but needs replacement. It came to me with a '78 260 motor (runs well, no smoke), which, needless to say, is a bit of an "underperformer" in a 4,500 pound car with a tall rear end. This is to be a non-collector, no-worries, fun car, that I will have no qualms about parking anywhere, leaving in the rain with the top down, or pushing shopping carts out of my way with at the supermarket. As much as I enjoy looking at "perfect" restored cars, I haven't had very good luck with fancy vehicles, and find my enjoyment level to be highest when my investment level is lowest (I also fondly remember that when I was a young-un and drove both a '70 Porsche 911 Targa and a '70 Cutlass convertible - no top, painted pink with a roller, the chicks showed a decided preference for the Olds , while the 911 mostly just got me dirty looks ).
Also, I am nearly fifty years old, and do not spend 5%, or even 1% of my time at the track. I will not race this car, probably not even against some kid in a Honda. I've got other fish to fry.

And so, in light of the above, on to the story...
I have just purchased, for the princely sum of $50 (Thanks, Joe!), a 1976 Olds 350 out of a 1967 Cutlass. The motor's got "74 Olds 350" in yellow junkyard paintmarker on the flexplate. The story from the previous owner was that it had had "valve work," then was put back together, but wouldn't start. It was hooked up in the '67 with the HEI to the resistor wire (Doh!). It had clearly been apart, and had clean, crystal-clear oil in it.

Upon disassembly, the first thing I discovered was that my damper puller was at the other house. Grrrrrrr.
The next thing is that this is a '76 350 (36D170761) with 14cc pistons and #8 heads.
New fuel pump, water pump, and a carb from a '74 Pontiac.
Computer HEI distributor.
Plugs rusty outside, but new inside - no carbon, never fired.
Inside looks typically filthy.
Lifters, lobes, and rockers show good wear patterns.
Valves look untouched, but may have new seals (They're lighter in color) - haven't had a chance to pull them yet.
Rod bearings PlastiGage to 0.003", have 0.014-15" side play, and show wear, but no scoring.
Oil pump shows wear, but no significant scoring.
Main bearings not checked yet (see "Grrrrrrr" above).
Cylinders have no ridge, some very slight crosshatching still visible (no scoring), and seem to be well less than 0.001" away from spec. parallel to the pin, and average about 0.00175" bigger perpendicular to the pin than parallel.
Piston skirts look good, no scuffing (did not pull them out yet - waiting until I can pull the damper).
Looks to have a new timing chain, old sprockets.

Other important points:
The motor is at my father's house 350 miles away, because I've got no good place to work on it here. This means I can't just "run out and check something."
A friend of my old man's has an old, mostly disused, machine shop, and will happily do straightforward work for me and then try to refuse to take my money (no dagnabbed Serti machine, but I do have a complete old-style valve grinding outfit in the basement).

The plan:
My basic idea is to finish disassembling this beast,
check other appropriate measurements (ring gap, main bearing clearance, etc.),
clean out the block and heads real well, with appropriate bottle brushes for the galleries,
do some mild and obvious porting on the heads,
mill to a CC size of about 60cc, to be determined mathematically after I've got all necessary values, aiming for a CR of about 10:1 (like my '70 Cutlass used to have),
new standard Melling oil pump,
reassemble using a new cam and lifters from CutlassEFI,
use the intake from my '70, with the QuadraJet that was on it back then (from a '69 442),
use either the HEI distributor from my 260, or the points one from my '68 455, and tune with a spring kit.
For the foreseeable future, this motor would run through the stock single-into-dual exhaust that's on the car now (remember - low investment!), no headers,
and hook up to the stock TH375 and converter in the car (I do have a low-mile TH400 from a '68 98 as well, if need be).
I haven't jacked it up to check, but the car feels like it's got a rear in the 2's (2:56? 2:73?).

The questions (and remember, if it doesn't give good bang for the buck, I don't need it - I'm not looking to shave a tenth off my ET):
Bearing shells - Clearance is good, shells show wear. Replace with similar size range, or just leave 'em?
Rings - I'll leave 'em if the end gap is within spec. If it's just a bit wide, replace or just leave 'em?
Heads - I forget the rule of thumb for decking them. Was it 0.006" = 1cc, or am I way off? I've also got a set of 4A's (403 heads). Both sets are unknown quantities, the 4A's have slightly bigger valves, the 8's have a slightly smaller CC.
Cam - I'll ask the man when I'm closer to making a decision, but I'm looking for a slightly "improved" version of the stock 1970 cam (smooth idle, stock converter)
Pushrods - Change 'em?
Rockers - Change 'em?
Valve Springs - Will check heights. Don't have a pressure tester. Change 'em?
Timing Chain - It's a new stock replacement right now, on original sprockets. If the sprockets don't look worn, should I go for a duplex chain? Is it worth it to go for an adjustable sprocket?

Well, that about wraps it up. I don't expect to be making any purchases for a while, but thought I'd get this out there. If you read this far, I give you a lot of credit.

Thanks,

- Eric

captjim

Where to start??

If the end gap on the rings is too much, it means the bore is large, new rings will not change that.

Get a pair of older 350 heads, chamber will be 68 or so. Cr will be 8.5 to 1. You do not need 10 to 1 Cr for what you are doing. You need torque focus on that. It is not going to be a screamer with a 350.

MDchanic

Like I say, I'll have to get back to it to make the rest of the measurements. I was under the impression that both the rings and the bore wear, so that replacing rings could account for a reasonable amount of bore wear. Obviously, not equivalent to a full out rebore and rebuild, but a whole lot cheaper if maximum performance isn't necessary.

I've got no problem with the idea of getting #5 or 6 heads, but I've already got a pair of #8's (and 4A's), and expect I can deck them for free, while buying others will cost money. Aside from the "hours vs dollars" question, is there an advantage to those over what I've got (remember, not a race engine)?

As far as CR, I've always been fond of compression - it gives you a snappier feel, and improves power, torque, and economy. It won't cost me more to get the CR I want, so I don't see a disadvantage. As far as octane - I already run nothing but 93 in both my bike and my DD, so would try for an engine that was happy on 92, "just in case." Seems high 9's to 10 would be about right for that with a bit of a cam.

- Eric

J-(Chicago)

I'd replace the rod bearings at least. The old ones tend to lose their crush over time, and once you jostle them, they are likely to walk away on you in the future. I'd just use stock replacements. Something simple and decent like ACL.

The rod side clearance seems a bit high for a stock motor. It may have been rebuilt at some point. Usually Olds motors are really tight, and you have to mill the rods down a hair to get that much.
.0030 on the rods is about as wide as I go personally. I shoot for .0025-0027, but that's just a personal preference. .0030 isn't bad.....better than too tight. Check all of your rods for roundness with the bore gauge. Again, olds specs are usually tighter in stock form.

I'd definitely replace the rockers, and pushrods.....your milling of the deck and intake of the head are going to force you to re-evaluate your valvetrain geometry.
Use the steel straps with separate pedestals, not the aluminum 1 piece ones.
The stockers are junk.

Springs and retainers will depend on your cam choice when you get to that point.

on the piston rings.... keep in mind, you're asking a lot of compression out of the ol' 8:1 junkers, and you'll never get them installed in the exact same place they all were carboned in place in the bores if you clean em up.

I understand Jim's point on the older heads, being a better CC starting point, but #8's are adequate for your plans.

defiant1

[quote=J-(Chicago);
I'd definitely replace the rockers, and pushrods.....your milling of the deck and intake of the head are going to force you to re-evaluate your valvetrain geometry.
Use the steel straps with separate pedestals, not the aluminum 1 piece ones.
The stockers are junk.
.[/quote]


Could you tell me what type (brand/manufacturer) you had in mind for the replacement rockers?

d1

J-(Chicago)

sealed power zr 856

http://www.summitracing.com/parts/SLP-R-856/

MDchanic

Summit says that these are 1:1.5 ratio, but if I recall Olds rockers are 1:1.6 - I assume it's a typo, as these look bone-stock, and a 1:1.5 ratio would reduce valve opening and reduce performance.

And thank you J and Jim for your answers so far. I consider all suggestions I get seriously, and I do appreciate them. I look forward to having a cheap, fun engine in a cheap, fun car, for as long as it lasts, and then walking away with no regrets, and an excellent bucks to kicks ratio.

- Eric

defiant1

These ones would work, wouldn't they?
http://www.summitracing.com/parts/CCA-1242-16/?rtype=10

d1

J-(Chicago)

Yes. Those will do the trick.

I'm not sure why the other one says 1.5 ratio

???

MDchanic

So the obvious question is, if the original pushrods and rockers are not bent or excessively worn (and I have seen situations where the pushrod wore right through a rocker, or where the rocker and pivot were badly scored and worn down), is it necessary or worthwhile to change them?
I mean, sure, we all want all the metal inside our engines to be new and shiny, and I have replaced things like this in the past, but if trying to only buy what I have to in order to make meaningful improvements or to prevent foreseeable problems, are these in that group?

Also, I thought of other questions to throw out there:
Oil pumps - Melling high volume or regular volume? I figured high volume if I'm leaving the oil clearances at 0.003", so as to be sure they get enough at low RPMs, but it this important or imaginary? Remember, this engine will never see the other side of 5,000 RPM, certainly not 5,500.

Timing chains - Prices range from $30.00 to $355.00 for a set of gears and a chain.
Is there any benefit in my application to a full double roller chain, as opposed to the cheaper factory-type ones that seemed to last 100,000 miles reliably? My motor's got a new factory-type chain on it, and I could replace the gears for an additional $12, or I could go for $30 or $60 or whatever for something better if there's a real payoff for it. Remember - no racing, factory converter, no revs over 5,000.

Thanks,

- Eric

Tony72Cutlass'S'

Hey Eric,

I was reading a book this past week (from motorbooks workshop) called V-8 Horsepower i believe, it's actually a pretty good series all the way from painting tips and engine tips and spruce ups.

The author made a couple suggestions in terms of what's the best equipment to buy for your money, and he kept pretty adiment about certain types of rockers, pushrods, valves and lifters. I have the book at home (as i'm at work right now) but this is what i remember, and i can check later to make sure it's right.

-Stainless steel valves are best
- Roller rockers are darn good at following a more agressive cam (depending what you'd like your cam and head/flow situation to be) i found one like he suggested
http://www.summitracing.com/parts/CCA-1442-16/
-in terms of lifters, he suggested roller type lifters again if you'd like to follow a more agressive cam

So these were his suggestions for valvetrain, in terms of brands, i'm looking at re-doing my valvetrain myself so maybe you guys could make some suggestions on which brands are the best, (edelbrock, comp cams?)

Cheers,

Tony

MDchanic

I was wondering how to "bump" this thread, and how to say this without ranting, and you've given me my chance, Tony.

First, let me say to Tony, and to J, and to Jim that I really do appreciate your feedback, and your suggestions, and your effort, and that I do not want this to sound like I am being critical of you guys in any way, especially since you were the guys who took the trouble to make suggestions to me.

[rant]

I took the time to open this thread with a fairly long and very specific post.
I did this because I have very specific questions that are not well answered elsewhere, that require a bit of experience with these motors to answer well, and that may be useful to others in the future.

My questions revolve around practicality and economy.
This is a minimal investment motor in a minimal investment car. I've got the motor apart, it shows minimal wear, and I want to be sure that any changes I make are worth the time and money. I am looking for maybe a slight improvement over stock 1970 350 performance, but nothing more. I do not want to change any parts that still work well, or that will not improve performance in the idle-to-5,000 (or, realistically, maybe idle-to-4,500 with the stock TH400) range.
I am not putting roller rockers in this sub-5,000 rpm motor.
I am not replacing factory rockers that show no signs of wear.

I understand what is "best" for a motor - I'm just not looking for what's "best" here. I'm looking for what works and is cheap. The factory didn't use what was best, and these motors routinely go over 100,000 miles with minimal maintenance in factory form. I could spend $5,000 on this motor, but I'm planning to spend maybe a couple hundred. I just want to know what things will actually make a difference, and which ones are overkill for me, (though they might help in a more "hot rod" application).

Look, there's a guy on here who got 41 replies to a question about how to make his exhaust louder! There are threads comparing $1,500 aluminum heads to iron heads with extensive porting, and how to make Chubby pistons and rods fit your motor. I'm just looking for practical, down-to-earth information about some simple stuff, and I feel like the the guy standing on the NYC streetcorner in rush hour asking passersby what time it is and getting the cold shoulder.
I know it's not sexy or esoteric, but I'd bet a lot of people could actually use information like this.
It's not like I can't do this without help, either. I've built Porsche engines for chrissake. I can make my own judgements, and they'll probably be fine. I just thought I'd ask the folks with experience, and I'm watching the tumbleweeds roll by.

[/rant]

- Eric

J-(Chicago)

If it ran fine, and shows minimal signs of wear..... Leave it as it is.
BUT Once you removed the heads your compression dropped a point, and you'll be looking at milling to get it back.
It's too late to stuff a nice cam and lifters into it, and call it a day. It has lousy compression.
You have to come up with $5-600 bucks I'd say. Cam, lifters, gaskets, and machine work.

You can shim the oil pump for more pressure, and a single roller timing set is fine. I've run a 12 dollar melling set to 104 mph the last 3 years at the track.

MDchanic

I expect it would have run fine, now that I've been inside it, but I bought it as a "guy I bought it from said he did some head work on it and then couldn't start it" non-running motor, so, for the $50, it was a crapshoot, and had to be opened up. If I'd had any idea how good it would look inside, I would never have bothered taking it apart, but, now that it's apart, I "mightaswell..."

Now that's practical information. If I can run a cheap timing set in a car in which I will seldom even floor the accelerator (well, kinda seldom ), then why waste money on anything "better?"

- Eric

71supreme

Hey Eric,

I wish I could add something. I just wanted to say I have been following this thread for the exact reason you've outlined.

It is a tough economy, and If I'm going to through and replace gaskets etc anyway, it's good to have a little info on what performance improvements are worthwhile to the most stock of engines, and which are only necessary because of other upgrades.

In my case I am hoping to learn of things that would be good to do to a stock motor that future upgrades are planned for, and are good to do while your there with minimal extra effort or $.

hehehe, I guess my only point is I am eagerly listening too...

MDchanic

I haven't personally gotten in touch with him yet, but CutlassEFI grinds cams, and seems to be VERY knowledgeable on the subject, so I am planning to ask him to make one when I am ready (certain of CC volumes, etc.).

Do you have an opinion on regular vs high volume?
About how much does pressure increase with a 0.180" shim?

I didn't know you could interchange those. Got any more info or rationale for it? I had been planning to use the existing rings, provided the end gap isn't excessive, since they're broken in and the cylinders have little wear - any reason why I shouldn't?

That's a Ford 292 seal (BS6141) or a Jeep 258 seal, right?

Hmmmm... That's one of my little obsessions on this project - I really like compression. I find that I like the feel of a higher compression motor better. If at all possible, I plan to bump the compression from the present ~8:1 to closer to 10:1, just enough that 93 octane works great, but 92 is iffy on a hot day. Other Olds I've had have had 10.25:1 motors, which felt great but needed a bit too much octane.

Not on the outside. The wear points all look good, though - no scoring or galling, very smooth, I don't see the metal worn down at all.
I'll check them more closely, but will probably keep them.
Also, if I decide to change them later, it's an easy job.

Thanks for the advice! I do appreciate it.

Hey, Mike. Yeah, there are a lot of things that can grow down south that you just don't see up here -- I'm not sure what's growing down there now, but I can definitely say that there's no money growing on trees up here in Maine this year.

As the Kinks said:
"Cheap is small and not too steep
But best of all cheap is cheap"

- Eric

Warhead

Ok, I'll chime in.
Dingle hone, and cast rings, new bearings, new oil pump. Basic stuff.

Others can advise you on a camshaft.

New CHAIN. Get an advance button kit from Dick Miller, or Dave Smith. Drill the sprocket, put 6 degrees advance in it.

If you want compression, ditch the #8 heads. Get some 4,5,6, or 7's. You can't mill enough off of the #8's for what you want. Fact of life.
Have the heads re-built, fill the cross-overs with aluminum, run an electric choke. New guides, springs, positive seals, and big INTAKE valves. If you don't pop for intake valves, have the 1.88's back-cut, and contoured on the backside. Have a 45 cut on the chamber side of the intake valve, round the chamber side of the exhaust valve (it helps battle reversion).

Use the 260 HEI once you re-curve it all in by 3000rpm. Q-jet with some CH rods, and a A-G hanger if possible. Adjust the secondaries to come in mostly on the pull-off (light spring wrap pressure). Insulate the steel fuel line with multiple layers of anything that rejects heat, keep it away from heater hoses, or anything hot.

Stock valve gear.

JMO
im

Stattiolds69

For what you want out of this nearly stock motor, I would stick with a standard volume pump, no need for a high volume, especially if you're sticking with the factory 4qt. pan. I'll second the #5-7 heads, milling that much off of the #8's might cause intake port mismatch and other problems. Just my .02 cents

cutlassefi

For the most part X2. Let me know when you decide on your combination and you're ready for a cam, happy to help.

J-(Chicago)

Even if you used #2 heads and a corteco gasket, I think you'd get 9.2:1 at best.

2blu442

Eric I know very little about small blocks. The first car I rebuilt got a 455 and I've been hooked on them since. But that said, I've been collecting Oldsmobile stuff for years and have a bunch of 330 and 350 engines and parts. I'm on the left coast so shipping wouldn't get much higher, but if I can provide any used parts I try to give good prices to fellow CO members. I do have lots of early heads and I should have a couple aftermarket intakes. If I can help with anything let me know. John

MDchanic

Thanks for the offer, John, but I think I'll stay away from West Coast heads for now because of the shipping. I'm keeping my eyes open around here, though.
As for the intake, I've still got the intake and carb from a '70 Cutlass I had years ago, so I'm good there.

I'll keep you in mind if I need other stuff, though - I've seen you've got lots of cool rusty metal around your place .

Hope you're enjoying the Spring - by my recollection, it's just about to green up out there!

- Eric