Corvette C3 of the Week

 

1981 Corvette C3

Frank writes:

Thank you for your efforts in showcasing the C3 Corvettes, still the best looking of them all.  I just finished my build this year and have won World of Wheels in my class and have an upcoming article in Vette Magazine.

I am not sure how to start the story of ‘Beauty and the Beast’.  The project did not start out the way it ended up, but I am sure many other restorations wind up the same way.  What started out as a nice street cruiser turned into a street beast.  The early corvettes are difficult to find in an unrestored condition needed for my project, so I decided on the last years of the C3 series and in my mind the last years the Corvette actually looked like a Corvette.

I found the body in St Pete, FL and hooked up my trailer and made a not stop 23 ½ hour round trip to pick it up.  Upon arrival I found a beautiful car that had meticulous body work and flawless PPG 3334 GM Corvette red paint.  It had a complete new interior, dash, door panels, carpet, seats, T-Tops and glass.  It was perfect and all I needed was the engine, transmission, and rear end to have my ride.

What started out to be a nice driver began to take on a life of its own.  Deciding on a 540 engine with 600+HP and 668 ft lbs torque that I had in my shop, this created a whole host of new issues to deal with. What transmission should I use to handle the HP and did I want to have an overdrive gear for highway cruising?  A Monster Transmission 700R won out over the 4L60 because of the control unit.  The Vette has a tiny dash and I already had plenty of new stuff to stick under it without another box to worry about.  The 4 speed 700R also required a change in the stock shifter so I chose the Hurst Competition Plus. It looks nice and performs well.

Now to the rear end assembly.  After some research on the wonderful WEB, I found RaceFab, the only company I know of who makes a unit especially for the C-3 Vette.  Gutting the rear suspension and rear end is not a task for the faint hearted but if you are a car guy and have a welder and a machine shop, it is a piece of cake.  However, a word to the wise, mock up is absolutely critical as there is NO room for error.  You will also need to be mindful of the small driveshaft tunnel in the Vette.  I chose a heavy duty GM 12 bolt truck rear end with Auburn Posi and Richmond 373 gears.  If you’re not headed to the track every weekend it will handle all you can put to it with street tires.   I topped it off with Baer brakes and slotted and drilled rotors.

After stuffing in the big block there was no way the hood was going back on without a whole lot of modifications.  I soon found out there were a few more things that needed to be done before things would fit.  First I had to remove a 4” section of the driver’s side firewall so the extra tall valve covers would fit.  If you remember, a big block did come in the C3 Vettes until  1974, but not with roller rockers, so they came with short valve covers.  Second was the cross member.  In a Vette it is forward and when you use a long water pump, have AC and alternator you will need a three belt crank shaft pulley.  Well, the only three belt pulley for a big block comes with an oversize outer drive that hits the cross member. No big problem, get out the torch, cut about 9” width and 3” deep notch in the cross member and get some ¼ steel plate and make a brace.  Once you get all the modifications done the ole’ big block drops right in.  Oops, forgot about the headers.  Thank goodness for Mack Jack on the west coast.

If you are using the rest of the original Corvette parts you are good to go, connect the wires, hook up the belts and hoses and your done.  However you may want to consider a heavy duty aluminum radiator.

II decided to make a few more minor changes, like rewiring the whole ignition to NASCAR switches and push start.  I also replaced all the gauges with AutoMeter Phantom.   I spent a month with a wiring diagram, a circuit tester, wire ties, heat shrink tubing, and multiple rolls of color coded wire.  I must say it turned out pretty cool.  The ignition switches are where the ash tray was and the headlight dimmer is a rocker switch on the console.

I won’t even get into the aftermarket AC system that they do not make for a late C3 Vette that I installed under my dash.  I told you it was crowed under there.

The Swoops front drive system is a must for a big motor in a Vette.  It keeps the components in front of the motor because space is limited on each side of the engine.  Only two things left to do.  One is the exhaust system.  Driving on the street I needed to have mufflers, but I also wanted to have some big ole’ 4” side pipes running down the side to give it some attitude.  If you have ever had a Vette with side pipes you know you do not want those things HOT all the time.  There has been many a curse word said when you get out of the car and touch the pipes.  So I decided to use electric cutouts for the side pipes.  I could close them off on the highway and open them up in town.  You should see the looks I get at the car shows when I fire up that big old motor and open the side pipes.  Wow!  That huge cam in the Barrett 540 also sounds awesome loping through the side pipes.  The second is the hood.  I know it would never go back on with the high rise intake and tall air cleaner so I decided to copy the Stinger hood from the 67 427 Vette.  Ecklers makes a stinger hood but it does not have the cowl look I wanted.  So I purchased another hood just in case I screwed it up and I did not want to match paint on another hood.  I took it all to the body shop.  We discussed what I wanted and a month later after extensive scoop modifications to widen and lengthen it, the hood was finished and what a nice addition.  It adds that little extra performance look that is not over kill.

It has been quite a project but all-in-all it has turned out better than my expectations.  It drives like a dream and by the way, I forgot to mention the Steeroids power rack and pinion steering.  The car cruises down the interstate at 70 mph at 2,000 rpms.

 

1981 Corvette C3

1981 Corvette C3