I own a 1963 Corvette Convertible with a 327 – 300bhp motor

Goss’ Garage

By Pat Goss

Q. I own a 1963 Corvette Convertible with a 327 – 300bhp motor.

Since it is an early 63 it has the Borg-Warner transmission in it.  The transmission needs to be repaired as it keeps coming out of gear.  I can’t seem to find any place to aquire a complete rebuild kit or anywhere to get a Borg-Warner transmission with the linkage to put into my car. Any or all information concerning this matter would be very helpful to receive.

A. I’m surprised you’re having such problems. Ten minutes on the Internet and I had too many options to make a choice. One kit comes from Eckler’s and seems to have everything you should typically need to do an overhaul.

 

1963 Corvette Borg Warner T10 4-Speed Transmission Rebuild Kit

$259.99kit

  • Includes All Major & Minor Overhaul Parts
  • All Parts Meet or Exceed O.E.M. Specs
  • Kits Include Hard-To-Find Parts

Super rebuild kit includes the following parts: synchro rings, counter shaft, needle bearings, thrust washers, snap rings, main drive nut, front & rear main bearings, springs and all necessary gaskets and seals.
1963 (C2) Borg Warner T10 4-Speed Transmission Rebuild Kit

Q. I have a 1990 Corvette 5.7 L-98 with auto. It has 25,000 miles. It has a new water pump, thermostat and sensors for the temp gauge. The primary fan is not working. The A/C fan is. If I drive in traffic I have to turn on the A/C. That fan keeps the temperature gauge out of the “danger zone”. Of course without the primary fan working it still runs a bit hot. What am I missing here? I have been told it is not the “main black box” I need to get the primary fan operational. I have been advised to hot wire the primary fan to the ignition. That sounds a bit chancy, but what the hell, nothing else is working!

A. The most common problem we find is the primary cooling fan relay so that’s where I would begin my test. Following is a copy of the wiring schematic for your Vette which will give you more information on testing.

Q. I have a ’87 C4 Coupe that I have owned for some 27+ years. Over the years I have made a few performance enhancements. Recently the car had begun to idle roughly and chalk up a “SES” light. With high mileage on the car I decided to make some maintenance parts service and upgrades. I installed a new IAC (Idle Air Control) unit, a Granatelli Adjustable MAF sensor, DUI Performance distributor, double roller timing chain, new spark plugs, and last but not least, Accel 24-lb Injectors. (I think 21or 22-lb were standard.) The car has had a Hypertech G2 early series power chip and Vortex air intake system with K&N filter on it for years.

I still get a little rough idle and worst yet is when I shower down on it underload it seems have a pre-detonation or other misfiring sound and hesitation going on. Wondering if the early series power chip is not cut to work right with the new higher injector flow rate. Is there a later edition chip that would be recommended for the new injectors or what?

A. I doubt that the chip would be your answer although it might be but that does beg the question of why you would install bigger injectors without making the necessary modifications to handle the extra fuel. In your case I would not drive the vehicle until you get the injectors dialed in. The first step is to determine if our engine is running too rich (too much fuel) or too lean (too little fuel). One way to check this is to remove the spark plugs and examine the electrodes and porcelain surrounding the center electrode. Toor rich should show as black and sooty while too lean could look extremely white and just right should be a light tan coloration.

If you have either too lean or too rich you might be able to compensate by altering fuel pressure. You can do that by installing an adjustable fuel pressure regulator which may have to be followed by a larger throttle body. If the engine is running too rich, reduce the fuel pressure and conversely if it is running lean increase fuel pressure.

A rich running condition can dilute cylinder lubrication leading to cylinder wall damage or piston and or ring damage. With an adjustable regulator you can dial down the pressure to reduce the amount of fuel delivered to the cylinders or in some cases by adding a bigger throttle body, you will be able to introduce more air to balance the mixture with the added fuel. But, with a bigger throttle body you will probably have to remap the ECU to make everything work together.

Another concern is the resistance of the new injectors which must match the resistance of the old injectors. This is important because if the resistance isn’t very near what the originals were you could have a situation where the injectors don’t open far enough and you could actually be running lean. This is a distinct possibility because you mention noise that suggests detonation under hard acceleration. A lean mixture causing detonation can knock the tops out of your pistons if ignored.

Injector resistance is an important factor in how injectors work. Injectors are nothing more than electromagnets that move their pintles when the electromagnet is turned on and off. The action is relative to the amount of current passing through the magnet’s windings. A proper amount of current flow through the windings fully opens the injector but should something reduce the current flow through the windings the injector won’t fully open.

Because resistance opposes current flow, higher resistance in the injector windings will reduce current flow which will prevent the injector from fully opening. When injectors don’t fully open the amount of fuel passing through the injectors is reduced and the engine runs lean. This can often be seen on a scan tool by extended injector on-times.

In the case of bigger injectors remember that like Goldilocks, bigger is not better, smaller is not better, just right is just perfect. Just perfect means that the injectors are nicely matched to your engine modifications. Bigger injectors by themselves do not mean more power but usually mean less power and often lead to engine damage. In this case you have added things to your engine that do not by themselves increase horsepower in any measurable way and do not offset or require bigger injectors.

A low restriction air filter does not make the engine take in more air (except perhaps at wide open throttle) because engines only take in the air necessary not the air that is made available. So, to get more power you have to make the engine take in more air then make that usable extra air available to the engine not the other way around. If more available air to an engine made it make more power then all you would have to do is remove the air filter and tubing before the throttle body and you would have no restriction which would allow access to every cubic foot of air on the planet and the horsepower increase would be immeasurable. But that just doesn’t work.

The amount of air an engine can ingest is determined by a number of things including its displacement, throttle body size, intake runner size, port size, port configuration, cylinder head flow, combustion chamber design, valve size, valve opening, valve opening duration, exhaust system flow, etc., etc. Much more complicated than the glitzy ads make it sound.

Not that these add-ons don’t work just that they need things to work with. In other words a complete system of modifications.

 

Q. On my 1967 327/350 I recently upgraded from original points distributor to new direct replacement electronic with matching coil. Alternator is correct brand new 63 amp replacement from Corvette supplier. Now when running, ammeter indicates charging rate pegged at 40+ amps which I’m sure is incorrect. Do I need a specific voltage regulator for the electronic distributor or can the regulator be adjusted accordingly? Voltage regulator is relatively new also but appeared to function normally with the original distributor.

A. The distributor should have nothing to do with the alternator unless you did something really tail-end foremost with your wiring. I would look for constant current flow on the field “F” terminal at the back of the alternator. That wire comes from the F terminal of the regulator and should be blue in color. The regulator senses the need for power out of the alternator on the battery “B” (large bolted-on wire, usually red) and sends a signal down the blue “F” wire to the alternator. A higher input on the blue “F” terminal means a higher amperage out of the alternator on the red “B” post back to the battery. If the “F” input from the regulator is constantly high the output will also be constantly high.

 

1990 Corvette Coolant Fans (Except ZR1 Models)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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