So I decided to build an engine

[Horseplay]

Decided to go ahead and put an engine together for my car. It's not the monster I originally planned or expect to stay in forever but it will be enough to make driving fun and it will get it back on the road.

It all started with a deal too good to pass up. Ran across the opportunity to snatch up a stalled engine project. All the major machine work having already been completed.

1971 Mexican 302 block. Bored .040 over. Reworked stock rods and crank. 1969 small chambered 302 heads (no humps!). Bigger valves installed, 1.94 intake/1.6 exhaust.

Since this was an unplanned build, I decided to go old school and see what could be had from the old iron heads. I'll save the bad boy aluminum ones for the next build. I would go ahead and fire up the die grinder and open these up a bit. The biggest gains on an old SBF head start by opening up the exhaust ports. They are SMALL. And irregular. And full of casting marks, etc. I matched them to the exhaust gasket size and opened the width and height of the runner considerably. I took the time to take lots of measurements at various depths and positions to make sure all were the same size when I put the grinder down.
On the intake side I also port matched to the gasket and raised the roof on the port runner. You can't open up the width much here as the push rod tubes are quite large and "bump" into the ports. I flattened the sides as much as I dared not wanting to risk breaking through. Again, lots of measurements to make sure things stayed consistent, port to port and head to head.

 

[Horseplay]

I didn't take a lot of pics of the short block assembly. The guy from whom I bought it had already done a pre-assembly and checked all the tolerances. Being the way I am, I went ahead and did it all again. Just to be sure. Everything was right so I wasted a lot of effort but at least now when I wind it up I won't be wondering if it will...you know... :mark.

Pistons are not forged but rather hypereutetic. Again, not my first choice but perfect for this engine's purpose. They have a -5cc slight done to them so with the small chambered heads, thin head gasket and near zero deck height it should give a final compression ratio in the 10.5:1 range, if not a touch higher.

As an older engine, this uses a two piece rear main seal. Make sure to offset the ends and use a dab of silicone at each side where the cap meets the block to be sure to prevent oil leaks.

The entire engine is held together with ARP hardware. Lots of engine assembly lube too. Just be careful you don't get any behind those bearings!

As a note to any guys out there thinking of putting their first engine together. Make sure to mark all your caps and rod pieces to keep them straight. I put an arrow on mine to make sure I orient things to the front correctly as well.

 

[Horseplay]

After cleaning, and then cleaning a few more times, it was time to reassemble the heads. As they had already been assembled prior to my attaining them, it was just a matter of keeping the spring shims and the rest of the valve train in order so that when I went to put it all back together there were no surprises. I took the time to check installed spring heights anyway. Just because that is how I am. :ns

I went with 7/16" screw in rocker studs because...well why not. You never know I may just wind this thing up really high one day. Be sure to put sealer on the threads as the studs do touch the coolant.

Next I bolted a head on to check for piston to valve clearance. I picked up a couple solid lifters (it will have a hydraulic cam) for this purpose. A little Play-Doh and a light coat of oil on the number one piston showed all was good.

Next I had to figure out my push rod length. Luckily I took this step because I found a 6.9" rod gave me perfect roller tip alignment where the standard 6.8" left me a bit behind center on the valve tip. I knew '69 was a weird year for the 302 in this area but I didn't know if it was because of the block or heads or both. Turns out in my case I needed the rare extra length.

 

[Horseplay]

After I got the valve train all sorted out I went back and did the final assembly of the cam and timing gear assembly. I ended up installing a grind with a moderate profile at a 268 duration. It's enough cam to sound serious but not the lopey monsters I had run in the past. I guess I've finally realized that my cars spend 98% of their time on the street and very rarely are they wide open tearing down a dragstrip.

This engine will be a low end torque beast on the street and should be a blast for the occasional stop light scuffle.

The cam was installed coated in assembly lube. You can't have too much lubrication when you crank up a hydraulic cam for the first time. It's also critical that you have the right oil and additives flowing as well but that can be covered later when I fire it up for the break-in.

Once the cam was slid home I held it in with the thrust plate. Make sure to install this piece correctly. The oil slot goes to the rear (engine side) as labeled. Easy to do backward. Pay attention. Red Locktite on the bolts. They only torque to 12 pounds. You don't want them coming loose.

Then comes the timing gear and fuel pump eccentric. Even if you are going with an electric fuel pump...put the eccentric in. It doesn't hurt anything and if you ever decide to run a mechanical pump you are good to go without tearing the front of your engine off. There's one catch here. Make sure to use the correct dowel pin to match your timing gear and eccentric. Later model 302s that use a two piece eccentric use a shorter pin. When assembled the pin needs to be flush with the face of your eccentric as seen in the pic.

Last bit of advice. Slip your timing cover on and look into through the fuel pump opening. You can get a good look at the clearance between the face of the eccentric and the cover. I had to file some material off the face of mine to gain adequate space. Last thing you need is it grinding against the cover and filling your oil with aluminum shavings.

 

[Horseplay]

So now things get interesting. How many times have you installed a new intake? Ever take the time to really look at how it installs in relation to the rest of the engine. In particular, the intake ports on the cylinder heads? If you think using studs to guide the placement takes care of everything take a minute to read this and look at the pics.

Lightly bolting the heads to the block, I laid the intake gaskets in place, allowing the tabs on the head gaskets to locate them. I found they could be shifted forward and backward almost 1/8". I also saw that they sat a bit lower than optimal based on port location. I placed masking tape on the heads and gaskets so that i could make pencil marks showing where the center of the intake ports were on the head and alignment marks on the gaskets to have them in the proper position to match the head ports. Next I placed the intake manifold on the engine and made reference marks on it to those on the head.

After removing the intake, I could then take measurements off the reference marks and determine how the manifold ports matched up to those in the head. Remember, I am port matching the heads and intake to the gaskets so to take full advantage of that work I needed the intake ports to line up exactly. There is A LOT of play in the bolt holes of an aluminum intake. I made new marks on the manifold that when aligned with the lines on the head would result in the two ports matching up perfectly.

It took a bit of time to do all this but if I hadn't, in my situation at least, the ports could have been up to 1/8" misaligned. Given the size of the ports themselves this is a HUGE volume loss. Which means a lot of missing power.

Once all that was worked out, I pulled the heads and finished up the port work. I then bolted them back on and did final valve adjustments.

 

[Horseplay]

Next came the front cover, dampner and water pump. Nothing too tricky here. I bought a new cover rather than take the old one off the original 289 sitting in my garage. For $40 it seemed a whole lot better a way to go. This meant I had to install a new front seal. I know a lot of guys just seat them by tapping around with a hammer. It works but I found a better way. Not having a socket that large, i rummaged through my tool box and came across my steering wheel puller. Taking the hardware off, the 1/4" thick round piece of metal was a tad wider than the bearing and allowed me to drive it in evenly as it should be done. As a tip, give the seal OD a quick finger swipe with a little oil before you drive it in. Also wet both inner seal lips with oil when you install the cover so the damper doesn't scratch it when it gets put on.

I don't use silicone on the cover gasket accept a thin smear around the water passages.

I splurged a bit on the water pump. I had a brand new one on hand but decided to spend a few bucks and get a Flowcooler unit. Look 'em up. Having battled hot running small blocks most of my life I figured this was the way to go. It is a VERY nice unit. Supposed to flow 30% more at idle. Since I am going with a pulley set-up that is under-driven it only made more sense to go this way.

The balancer is the stock unit that was balanced with the rotating assembly. A quick shot of black spray paint and she was good to go. A new ARP balancer bolt locked it in place.

 

[Horseplay]

Turning it over, it was time to button up the bottom but before I could do that I had to install the oil pump. Nothing exotic here. Just a tried and true Melling pump and new pick-up. I do recommend spending a few extra bucks and getting a hardened pump drive shaft. Again, cheap insurance against something going wrong and having to tear things apart later.

I guess I should have mentioned back in the beginning. Before starting to assemble anything, I ran a tap down every hole in the block and heads. It's vital that the threads be clean and straight so that torque readings are accurate. Its also a very good idea to put a little engine oil or other lube on the bolt threads when installed.

Anyway, from here on out things get more cosmetic. My car has a lot of billet parts and the engine is no exception. Lots of polished aluminum. The oil pan, valve covers and air cleaner included. I wanted something old school looking but still not off the shelf. In my case that meant using paint to detail things. My car is painted black so I incorporated that color into the fins on stuff. Here are some pics of the oil pan getting painted. I did the valve covers the same way.

 

[Horseplay]

Once the pan was painted, it was time to seal up the bottom. Before I could do that though I broke out the Play-Doh one more time to make sure the pick-up was correctly positioned near the bottom of the pan. It only takes a minute to make sure that your pump can suck up the oil your engine needs properly.

After that was verified, I used a one piece silicone reinforced gasket to seal up the pan install. I used stainless fasteners to secure the pan. Use Locktite Blue on the pan bolts and do not over torque them. As with the manifold, work inside out and in steps. The pan I used has a fairly hefty flange plus there are thicker bosses where the bolts pass through. Stock pans can be easily warped by over tightening the bolts. By using the silicone reinforced gasket I did not need to worry about coming back and re-torquing. If you use a cork gasket (why would you unless concours) you may need to re-tighten the bolts later.

 

[Horseplay]

Now that the bottom is sealed I turned my attention back to the top. Namely, installing the intake. Nothing fancy here. I detailed how I determined it's final resting place earlier. All I had to do now was bolt it on.

I used Felpro intake gaskets that are of a more universal fit. Meaning in this case that the water passage cut outs are not exactly for this year 302. I needed to trim a piece out at the water passage openings. Once that was done I put a very small amount of gasket shellac in a few spots on the head surface of the gasket so that they would be securely located and held in the exact position my earlier marks indicated. In addition, I used a small bead of silicone sealer around the water passages on the cylinder heads and a much lighter "smear" coating of it on the intake side of those same passages.

After that, all I had to do was CAREFULLY lower the intake into position and torque it down. I used ARP stainless fasteners to do this one. As with any aluminum intake, I took care to follow proper torque sequence (inside out) and pulled it down to spec in four steps. I came back later and went one more round after the sealer had time to set.

I went ahead and screwed in some plugs, installed the fuel pump and set the carb and air cleaner and valve covers in place for now to seal it all up. I have the front pulley system, alternator and power steering pump on their way. Haven't quite decided on distributor yet.

 

[Horseplay]

I'm not sure why the engine color looks so orange in the pictures. It's actually a dark cherry-like red. It matches the metal dash in my car.

 

[msell66]

Nice write-up!


If you have such a chevy engine fetish, why not just build a SBC???

 

[Grabber70Mach]

Nice write-up, Thanks for taking the time to do it.

Sent from my VS980 4G using Tapatalk

 

[B67FSTB]

Nice write-up, Thanks for taking the time to do it.

and as soon as it runs , I would like to hear it !!!!!

 

[tarafied1]

that would look great in my 72 Chevy pick-up :hmm

 

[msell66]

that would look great in my 72 Chevy pick-up :hmm

Baaaaa hahahahahahahahahahaha






Told ya

 

[Horseplay]

It's not orange!

When I get back home I will open up the garage door and let some natural light in. I think the fluorescent lights are messing with the color in the pics.

 

[msell66]

It's not orange!

Yeah, yeah...and J's car isn't yellow!

 

[guruatbol]

I have been wanting to find a finned oil pan like that for a long long long time now.

Where did you find it?

I settled for chrome on the 67 because I couldn't find one like yours for it.

Mel

Sent from my DROID RAZR HD using Tapatalk 2

 

[70 StangMan]

I'm not sure why the engine color looks so orange in the pictures. It's actually a dark cherry-like red. It matches the metal dash in my car.

Sure looks err-ange. :dun

 

[Fast68back]

Nice write-up!


If you have such a chevy engine fetish, why not just build a SBC???

+1