1984 Chevy Z28 Pro Tourer

I once owned a 1984 Camaro Z28.  I’ve always had a thing for cars, ever since I was a kid and always wanted a Camaro.  I owned a 6 cylinder model before the Z28, the 6 was owned because my dad would not let me get an 8 cylinder car, but I still wanted a Camaro.  The 6 cylinder was not enough, I wanted the big dog and I finally found one.  It was such a steal, some lady divorced her husband and she got stuck with this car.  It had 69,000 miles on it in 1998 and I bought it from her for $2500!  You can’t get a decent Camaro for that price now!  This car really started my love affair with the Camaro and the art of driving.

Unfortunately I messed this car up!  It was a Z28 model with no paperwork with it.  I was still young and had not ventured into the “fix it myself” territory of enthusiast yet.  This was the car that made me start tinkering.  It was fast, and I wanted it to be faster!  If you look up the specs on a 1984 Z28 you will find that the engine that should have been installed was a 305 cubic inch V8.  So when I did tune-ups and modifications to it, I was putting parts that were to go on a 305 in it.  Only later did I find out that this particular car was a leftover police package car that actually had a High Output 350 in it! (Or had a 350 swapped into it at one point….)  I believe that most of the parts were similar enough that the engine didn’t suffer too many issues due to my lack of knowledge, but there were definitely issues do to me messing with it!

I used to dream about what I was going to do to that car and came up with a pretty detailed plan on what exactly I was going to do with it.  I was never really into drag racing so I wanted a car that could handle very well and sustain high speeds without an issue.  I wanted to build this car to run in the Silver State Classic race.  The goal was to build the car, drive it to the race, race it, and drive it home.  So I essentially planned a pro touring car before it was a cool thing to do!  Too bad I didn’t actually build it…..

This car was a 5-Speed car, and I was young and without too much money.  I ended up doing a lot of calculations to figure out what kind of horsepower I would need to approach the speeds needed to run the class that I wanted to run, which was the 180MPH class.  I wanted to maintain the 305 engine that was in the car, but modify it to produce the required horsepower.  That being said, I would have used some of the tools that are linked in this post.  These were not available then, but I am going to attempt to recreate my plan here.  I found that the drag coefficient for a 3rd Generation Camaro was .34 and it had a Frontal area of 21, I got this information from here.  These two numbers plus the weight of the car, I’m going with a rounded 3500 with driver, are needed to do the calculation for horsepower needed.  So according to the Wallace Racing website calculator, I would need to make at least 290HP (most likely at the wheels) to get to and sustain 180MPH.

My 1984 Z28 should have been equipped with an L69 5.0L engine producing 190HP.  So I had my work cut out for me.  I needed to make 290HP at the wheels, adjust for 25% drive train loss, and I would need 387HP to be produced out of that little 305 motor!  My plan was pretty simple back then, and would be the same today; I was going to put on a better flowing set of heads, most likely the L31 Vortec Heads.  According to Car Craft, these heads would need to be milled in order to not lose compression when in use on the 305, my plan was going to be to leave them the way they are for the lower compression.  I would install a hopped up camshaft, probably  the Comp Cams dual-pattern XT262H Xtreme Turbo unit, It appears to be similar to the one from the Car Craft build, but for a boosted application.  After that would have been the supercharger!  I was looking at a Weiland 142 Pro Street Supercharger kit for the Chevy 305/350.  This advertises between 25% and 40% increase in HP.  So If I were to get 290HP at the crank with the heads and the Camshaft, taking into consideration that I would lose some performance gain of the heads with the lower compression ratio, then pop 40% increase in HP from the supercharger, that would have gotten me to 406HP out of the 305!  Of course I would have to run the largest pulley that they had for the Weiland unit, but with the lower compression ration I should be ok.  That horsepower number may not be correct, I’m just bench racing at this point but I was hoping to be close!  I was going to top the whole thing off with a Holley 700CFM 4-barrel carburetor.

Now for the gearing, to get that car to 180MPH during the race and be able to drive it out there (from New Jersey!) without stopping every hour for gas was going to require some thought.  As stated earlier, my car was a 5-speed and I planned to keep it that way, and this was not going to be a drag car.  The gear ratio’s for the 5-Speed manual were as follows:

1st 1:2.953

2nd 1:1.938

3rd 1:1.337

4th 1:1

5th 1:.728

The stock vehicle had a rear drive gear of 3.15 and according to the Tremec website this should have gotten me to 168MPH.  This stock setup would have also put 75MPH in 5th gear at 2250 RPM’s.  Not too bad on gas, but not great.  I was going to swap out the rear gear to a Richmond 2.73 unit to get my top speed at 5000 RPM to be 193MPH and would have set the 75MPH cruising speed below 2000 RPM.

So the plan was pretty low budget, heads, cam, supercharger, and a rear gear.  So far the costs would be under $5000 (I already had the car).  To be able to run this race, I would definitely need a suspension, a stable car is definitely important at that speed.  The idea behind the suspension upgrades would be just to stiffen the car up.  Eibach Sportline springs and adjustable shocks at all corners, this would allow me a little bit of flexibility with the ride quality and the adjustability of the shocks to for different conditions.  The Sportline springs would have been stiff but they handle so well it would have been worth the trade off!   I would have also put in larger sway bars and sub frame connectors to make the car more stable in the corners and to help lessen body roll .

Today I know a little (a very little) more about cars and would attempt to pull a Vortec 5.3L from a truck and drop that into the 3rd Generation Camaro.  These engines put out decent horsepower from the factory, as stated in this post, and just bolting on a supercharger or even just a better intake manifold and Camshaft  would put me close to the horsepower numbers that would be required without spending anywhere near the same amount of money.  I believe that I could do the above setup today with a 5.3L, the suspension, and the rear gears for less than $3500.  That’s also sourcing a car!  We’ll see if I ever get this far if that budget number holds up!

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