C4 Corvette Project Cars - Disco Dread

The Accel SuperRam manifold... 

   

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The Accel SuperRam manifold is a bolt-on for any Corvette TPI engine and pushes the peak horsepower point closer to 5,500 rpm, where you can make some power. When combined with good heads, a cam, and exhaust, this emissions-legal manifold can support more than 500 hp.

Brakes are the other big modification you can make, although even the lowliest '84 C4 came with 12-inch front rotors (11.5-inch rear) and a decent PBR caliper. You could also step up to a Vette Brakes & Products C5 conversion that bumps the rotors to 13 inches and C5 calipers, but this will also require 17-inch wheels, which isn't a bad idea anyway. In fact, that 17-inch wheel and tire upgrade should also be a requirement if you plan on attacking the local road course with this package. And why wouldn't you?

LS Motor Swaps
Here's where it gets fun. Sure, you can bolt a hot Gen I small-block into a C4 and go fast--that's been done. Let's talk about boosting the C4 into the 21st century with an LS-series engine. The swap isn't that difficult, and there are a couple of companies that offer parts. This is a great idea whose time has come. Consider an all-aluminum LS1 or LS2 engine with 500 hp that's also going to pull 150 pounds off the nose of a car that is already at 3,000 pounds. Combine that with a TKO-600 five-speed trans that is durable and light and you have a killer combination in a car that now weighs around 2,900 pounds (minus driver). That's an easy 12-flat car on the dragstrip at around 117 mph. Think about dusting some clown in a C6 who thinks he has the baddest act in town. He'd have to call for an emergency meeting with his therapist.

We talked to Dave Emanuel, who swapped an iron 5.3L LS engine into an '87 C4 Vette he bought for $3,000. This entire conversion is detailed in a series of stories in our sister magazine Corvette Fever. Emanuel also installed a Tremec TKO-600 five-speed, retaining the C4's stock hydraulic master cylinder. You can peruse this series online at corvettefever.com. Speed Hound Performance in Georgia offers both custom engine mounts and a set of Melrose-coated headers for this conversion that combined will run about $900. You'll also need a Corvette-style accessory drive to clear the steering on the C4. These accessory drives can be expensive, but you can also go with a Kwik Performance conversion for just the alternator and power steering for $287. We outlined this kit in a previous LS-series engine accessory drives story ("LSx Accessory Drive Swap Guide," May '09). You might also want to get rid of that cheesy digital dash that the early C4s came with. A company called VettAid is marketing a nice analog gauge package that plugs right into the stock C4 wiring harness.

For a killer road rocket,...        read full caption For a killer road rocket, the best swap is to bolt in a Tremec TKO-600 trans. You can piece together the parts yourself, or Keisler offers a complete swap kit, including hydraulic clutch parts to convert over from an automatic. This will save a ton of grief.	You can find complete, used...        read full caption You can find complete, used Dana 44 rear axle assemblies if you search long enough. We found this seller at the Pomona swap meet. The Dana 36 can be upgraded to work, but it's not nearly as strong as the Dana 44. The stronger 44 can be identified by its two cover bolts at the top of the centersection instead of one bolt for the 36 model.	The stock Corvette comes with...        read full caption The stock Corvette comes with forged-aluminum control arms and a camber curve intended for spirited driving and competition. Combine this with at least a 275/40R17 tire on all four corners and you have the makings of a car that can pull some serous lateral g's.
Factory C4 12-inch discs are...        read full caption Factory C4 12-inch discs are plenty good for most applications, but if you're going to take on the road course, upgrades such as this Wilwood kit or even a 13-inch rotor C5 conversion would be a wise investment.	Swapping an LS-series engine...        read full caption Swapping an LS-series engine into a C4 Corvette will require motor mounts and headers but otherwise is a relatively straightforward swap. The C4 digital dash does not require a C4 computer, so that's not a deal breaker. Imagine an all-aluminum LS engine making 500 hp under that clamshell hood, and a gold-chainer C4 suddenly becomes a road course rocket.	These are the Melrose-coated...        read full caption These are the Melrose-coated headers and the engine mount plates that take a Napa motor mount PN 602-1147.
We found this '03 iron 6.0L...        read full caption We found this '03 iron 6.0L engine and 4L80E automatic at the swap meet. Combine this $2,500 deal with another two large for an '85 C4 and you have the two big ingredients to build a killer supercar.