92RS_Ttop

iTrader: (3)

Ok, so this is my first time rebuilding a SBC 350 and I'm almost to the point where I am ready to start it up and break it in. I've been reading and searching and searching and reading on here and Google since I started rebuilding the engine and I'm still not 100% on some things.

1 - For the initial break-in, I was planning on using regular 10w30 oil with the STP additive. Is this ok, or should I hunt down the GM EOS? From what I've read, the STP and the EOS are basically the same thing.

2 - Should I set the timing during the 20-30 minute break-in period, or should I get it close, run it, and then set the timing after that period?

3 - Same question for the carb(Holley 600CFM, vac secondaries)? Set it up during the initial run, or get it close and then set it up afterwards?

4 - After the 20-30 minute break-in run, it will be around 2-3 weeks till I will have the rest of the car together enough to be able to actually drive it to seat the rings. Is this going to be a problem, or will it be ok? I don't want to put the car completely back together just to have to take it all apart to remove the engine because something goes wrong during break-in.

5 - Not engine related, but part of the build. I just rebuilt my T5 as well. Is there any break-in procedure for this, or is it just a rebuild-and-drive-it kind of thing?


The engine:

It's a basically stock 350 from an 70-72 El Camino, 2 bolt mains, stock dished pistons with 305 heads(14014416 castings) that I've ported and installed new springs and valves into. I'm using new Lunati hydraulic flat tappet lifters with a slightly(3K miles) used cam. I used the Comp Cams Assembly grease on the cam/lilfters, PN# CCA-102.



And the really stupid bonus question:

I noticed after I got the heads on that the driver's side head has 3 mounting holes in the front and 1 in the back, while the passenger's side head is the opposite. It has 3 mounting holes in the back and 1 in the front. Is it possible I got 2 driver's side heads or am I just overthinking things?? They were given to me as a matched set by a friend who was a mechanic for years and has rebuilt many SBC's over the years so I really didn't think to look at them.

Atilla the Fun

Check the timing as soon as possible after it first fires, because if it's not advanced enough you'll have your exhaust manifolds glowing (never break in an engine with headers) and too far advanced is risking a carburetor fire.

92RS_Ttop

iTrader: (3)

Why use exhaust manifolds over headers? I've never heard of that one before.

rgarcia63

Hmm, my GMPP fast burn alum heads have 3 holes all around. I think the stock ones did too. DTC is fine for the 20 minute break-in, if it's a roller cam just startup set the timing, change the oil and go.

Saculia

iTrader: (1)

New engines run very hot. You don't want to break the engine in with new headers since the coating on the headers will get damaged. You can use a set of old headers, and preferably the stock cast iron manifolds. After the initial break in you can install the new headers. The coating on new headers needs to cure properly, which can't be achieved at the high temperatures that new engines run.

92RS_Ttop

iTrader: (3)

That makes sense, I hadn't thought of it damaging the headers. I'm mainly concerned with making sure I don't damage the engine. I'm bought a cheap set of used headers for this build and plan on upgrading to larger ones once I get the rest of the exhaust system upgraded. They just have black paint on them so if the paint peels from the heat, it's no big deal to me.

five7kid

iTrader: (14)

If you switched them side-to-side, you'd find that the driver's side head would now have 3 mounting holes in the front and 1 in the back, and the passenger side would now have 3 mounting holes in the back and 1 in the front.

TPI

Wish you the best with the build, Im on a couple dozen thousand miles
into my build similar to yours, mild cammed TPI 350 with 081's. Should be
a cool ride with a carb on top, my TPI car is very fun to drive around town,
and she has some thunder under the hood!

I broke my car in with headers, break-in's arent so much a threat
with a hyd. roller, but I still let her settle. I didnt really have a choice,
I dont even know where my stock ext. manifolds are! Hehe.

and, I have no idea what to say about the cyl. head question, lol!

92RS_Ttop

iTrader: (3)

57 - Thanks, I got that much . I checked all the coolant passages before I put them on and everything lined up so I assumed it wasn't a big deal. So if I needed the extra holes on the other side I could just swap sides. Good to know.


TPI - Thanks! I'm hoping the engine will last. I'll have to baby it probably since I still have the T5 in the car. At least until I can find a T56 cheap enough.

five7kid

iTrader: (14)

No, if you switched them side-to-side, the holes would be exactly as they are now.

neglectedz28

the bolt holes in the heads are normal make sure you check the mounting for your accesory brackets to make sure you have the correct # of holes on the correct side.

92RS_Ttop

iTrader: (3)

Yeah, you're right. Don't know what I was thinking there.

92RS_Ttop

iTrader: (3)

That's on the to-do list for this weekend. I'm only gonna be running a power steering pump and an alternator for accessories so I'm not too worried about it though. IIRC, the alternator bracket bolts to the water pump and possibly to the intake manifold, not to the head.

neglectedz28

if i remember correctly the lower alt bolt goes in the head.are you running a vbelt set-up or serp belt.because i am just going by memory from my 85

92RS_Ttop

iTrader: (3)

V-belt. Sorry, I forgot to include that in the description of my setup. The driver's head has a bolt hole in the lower outside corner of the head I believe. If I have to fab a custom bracket, its not a big deal.

92RS_Ttop

iTrader: (3)

Thanks for all the help, I finally got it started up last week to find out my return line was leaking from the fitting I used to adapt it to the regulator. The engine ran for all of 5 minutes before it started spraying fuel. After a lot of searching, I found one that fits better and doesn't leak.

I also found out why painted headers aren't recommended for break-in. When the paint started burning off, it filled my entire garage with such dense smoke I couldn't see my wife in the driver's seat while standing in front of the car.

Started it up again yesterday morning to finish the break in process and set the timing/tune the carb and it fired right up on the 2nd revolution. It ran great till the valve cover gasket on the passenger head started leaking oil onto the center pipes of the header after it warmed up to about 220. At least that's what the gauge read when I noticed the oil leaking, the header had been smoking a bit before that, but I figured it was just the rest of the paint burning off. Oil pressure was only about 30 PSI at 2000RPM, but I figured that was due to having the wrong sending unit.

I also heard a weird sound coming from that head, about the area of the center 2 pipes of the header. It happened irregularly, not constantly. It was a pinging/ticking kind of sound, like metal makes as it cools down from being too hot. I'm wondering if I've got a detonation issue or if it was just the header "settling in" when hot? I've never heard an engine ping before so I'm not entirely sure what it sounds like. I also thought it would come from all cylinders, not just 1 or 2? It definitely was coming from the passenger side only. Is it possible it was because of the oil leaking on the headers? I'm only running about 9.2-9.6 SCR, but I have about 2 gallons of old gas from last November mixed with 5 gallons of fresh(2-3 weeks old) gas in the tank and thought that might contribute to the engine pinging/detonating. I haven't had a chance to set the timing yet so I don't know what it's at.

armdale

This is what I was taught by an old engine builder. He taught me when I worked in his body shop.

1] The timing should have been set up correctlly when you degreed in the cam to specifications. Only a final setting is needed after the distributor is installed. This is done after the engine fires and runs long enough to finish.
2] Check for oil and coolant leaks before start-up. Check levels. No thermastat untill after break in and the engine runs cool.
3] The person in the vehicle must monitor water temp. , oil pressure, {temporarily install one if the car doesnt have one, Hold it in your hand and run the plastic line around the door sill}
4] Start the engine for about 30 seconds no reving and then shut it off. Check for leaks again and for hot wire etc.
5] Start the engine again no reving just let the mechanic under the hood adjust a slow idle by hand. You will hear the engine become less taxed and the heat will probablly be rising a bit. Shut it down and change the oil and filter. Cheap oil untill later unless you care. Check the oil for water and the coolant for oil. If there is any go back to the rebuild you have a serious problem and the engine wont last.
6] If not problems start the engine again and this time the mechanic under the hood can accellerate the engine to 2500 rpms or so. After a few mins or when the temp rises shut down the engine and change the oil and filter, Check for leaks. Check for water in the oil--Oil in the coolant. Go back to rebuild if it is present.
7] Fill the oil this time with good oil and a good filter. NO SUPER LLOBES like z-max or the engine will not seat the rings. At this point the engine should have slowed down smoking and almost stopped.
8] Test drive it. Go about 1 mile under a normal rpm. Check for leaks!
Go for about 2 miles. I like to get a bit aggressive here as long as the heat doent go up. When I return I change the oil and filter and drive it for about 500 miles..Keeping a Check for leaks' I change the oil and filter oil and filters again and then its a normal schedule.

This guy rebuilt engines for several decades including high performance engines. He did this ritual so he didnt loose engines and made a steady profit. Changing all oil and filters might seem stupid but it saves new parts from metal flakes and the engine runs for a long time.
Hope this helps.

92RS_Ttop

iTrader: (3)

That's about the process I'm going through it seems like. I checked and rechecked for leaks before firing the engine the first time. I tested the fuel line fittings 3 times for leaks and had no problems. The fuel fittings didn't start leaking until after the engine had been running for about 5-6 minutes. No noticeable oil leaks the first time I ran it. Temp was good, oil pressure was steady.

Second startup, the temp was rising but not overheating. I had a large fan in front of the car(no bumper) blowing full speed and turned the radiator fan on manually at about 180-190*. The oil leak didn't start until the engine had ran for about 5-6 minutes. Simple fix, not a big leak, but I didn't want any chance running low on oil. It leaked maybe 3-4 spoonfuls of oil out before I shut it down. My wife is not a professional mechanic, but she's not a complete novice either. She would have shouted had the gauges been way off.

I bought the cam used so I don't have a degree card or any kind of spec card on it. I measured the lift and intake/exhaust centerlines to get an idea of what it will produce power-wise. I don't have a degree wheel, nor do I fully understand how to use one. I do know it's installed correctly following the generally accepte(Engine at #1 TDC, timing set installed dot to dot).

The oil is your basic Pennzoil 10w-30 "dino oil" with STP's Oil Treatment added for the necessary Zinc anti-wear additives.

After the first run, the oil level was good, not coolant in it. The coolant was a bit low which is typical of a fresh coolant fill. I topped it off, there was no oil in the coolant. I haven't had a chance to check them after the last run but I don't expect any problems.

92RS_Ttop

iTrader: (3)

So I checked the engine out last night again. The coolant was a bit low, topped it off. It looks good otherwise. Oil was good, haven't lost any noticeable amount on the dipstick, and its still nice and clear. Fixed the valve cover gasket, it looks like I used bolts that were too short to properly clamp the cork gasket and the pressure pushed it out. New gasket is on with longer bolts and new gasket adhesive to glue it to the cover. I think I also found the source of the noise on that side. I don't think I got the valves adjusted properly as the pushrods spin very easily on most of the cylinders on that side. On the #4 intake valve, I can even wiggle the pushrod up and down a bit. Do I have to go back and adjust all the valves, or can I just tighten the rocker nuts on the ones that are loose? Pretty sure I should do them all in order, but hoping I don't have to.

afremont

You should be able to turn the pushrods, but you shouldn't notice any up and down movement. Keep a close eye on that #4 intake rocker to see if it loosens up again.

92RS_Ttop

iTrader: (3)

Thanx, that's what I was thinking. I'm gonna pull that cover again and tighten it down since I forgot to do that last night. Hopefully I won't mess up the gasket in the process.