Day 2 '68 Chevelle SS

[Derek69SS]

I'm a long-time lurker here, and finally signed up to share this Day 2 Chevelle I bought last summer. Previous owner bought it in 1974, and last drove it about 1985. He passed away recently, and I bought it from his brother.

68 SS396 Fathom Blue/Medium Teal
Originally bench seat 4spd, now has buckets.

Engine in it was an L78 out of a 69 Nova, JH suffix.
Trans is a numbers-matching M20, and has KF (3.55 posi) 12-bolt.
1111169 Distributor in the trunk likely original to the car as well.

It has some cool period speed stuff on it, such as Mr. Gasket Vertigate, traction bars, Steel bellhousing, a Fly Eye air cleaner (was in the trunk and warped from being burnt), L60-15s on 15x8 Corvette ralleys, Headers, Thrush glasspacks, etc.

I sent the VIN from the L78 block to Wes at "Lost Muscle Cars" and he found the car is registered in Pennsylvania! I'm now in contact with the owner, and might be able to reunite it with its original car, which he had no idea was really an L78 car! (but was known to be an SS 4spd car)

The one oddity of the stamp is the last digit being double stamped with an 8 over the top of a 7.

7 is lined up in the gang, and the 8 off center assumed to be a factory "fix" from someone forgetting to change the last digit in the gang holder, and stamping the previous car's VIN on it. Knowing the history of the engine, I have no other explanation for the double stamped digit.

[Derek69SS]

I decided to get the car roadworthy this summer, and drive it just the way it was in 1985 when it was last driven.

I cleaned the garage to host a Northstar Chevelle Club "work meeting" to have some help and motivation to try firing up the L78... honestly, I spent as much time cleaning as it would have taken me to just do it myself, but it was a good feeling to get this done, and made for a fun day with a bunch of great people tinkering on a cool old project.

Unfortunately, there were issues with the #1 cylinder. There was a stuck exhaust valve, so we had to dig deeper.

Any hope of firing it up was gone when this HUGE crack in the #1 cylinder wall was found.

[Derek69SS]

After everyone else went home, the kids and I got to work getting the L78 pulled out so we could drop this rat in its place. We'll break it in on a 4bbl, but eventually I want to put this Edelbrock TR2 on it and really lean into the car's "Day 2" flavor.

The engine is an unknown, acquired when I bought out a barn full of parts from an estate. It's a 1989 Marine (9XA suffix) 454. Forged crank, roller rockers, 074 "L88" aluminum heads, but never looked too deep into it yet. Borescope through the spark plug and drain plug revealed a few things about it. Pistons are 13cc dome, part number came back as 1971 LS5, so it will only be about 8.5:1 with the 118cc heads. 4-bolt mains and 7/16" dimple rods, and cam measured out to .525/.510 lift, so a lot milder than I expected from an engine with these heads. Everything looks fresh, heads never been run, pistons clean, and still has assembly lube on the cam. It already had a Chevelle pan on it, so we just dropped it in as-is.

Transmission VIN stamp confirmed to match the car once it came out. I could read the date before, but VIN was covered with grease.

[Bill Pritchard]

Nice looking Chevelle! Great to see your kids involved with the project Bet the guy with the Nova is bummed about that cracked block.

[big gear head]

A sleeve will fix that right up.

[Too Many Projects]

Originally Posted by big gear head

A sleeve will fix that right up.

Hey, Derek, good to see you posting..
The block is already .060 over. How much more can be removed for a sleeve and then have that bored to match the rest ? Wouldn't it need all the cylinders sleeved at that point and bring it all back to standard ?

[Zman1969]

Cool project Derek! so that low compression may make it run like a pig you may want to swap for some small chamber heads or get bigger domed pistons! my 69 is being built day two also I'll be following along on your journey
did you ever find rest of the valve? LOL

[Derek69SS]

Originally Posted by Zman1969

Cool project Derek! so that low compression may make it run like a pig you may want to swap for some small chamber heads or get bigger domed pistons! my 69 is being built day two also I'll be following along on your journey
did you ever find rest of the valve? LOL

I have a 427 sitting here that's supposed to be 12:1 with 840 heads, so swapping heads between the two would make both of them better. The goal for now is just to get the car running and driving on the cheap with stuff I have on hand. After throwing money at another car for years, this one is going to be fun to play with mostly used parts and stuff I have laying around.

We broke the valve on Saturday. The valve was stuck open, so when we set the lash, without realizing it wasn't closed, the rocker was tightened down enough to make it hit the piston. Whoops...

[L_e_e]

An important thing to remember when setting valve lash is to compare the thread reveal relative to the other valves, if one has more thread reveal compared to other valves then something is wrong.

[SuperNovaSS]

If the other cylinders are still nice, a sleeve can be put in that same cylinder and bored to match the piston if the piston is still OK. The block has to be bore a lot more that .060 to install the sleeve and the sleeve some smaller than standard so all is well.


Jason