"84 CFI Project - Thread from Digital Corvettes

[Cartrax]

Here's a thread that may interest some. It's my thread, probably should have started it here instead but I wasn't aware of this special forum at the time. Kind of lengthy - the meat starts on page 4.

DigitalCorvettes.com - Times for a ~320 HP "84?

 

[nelson84]

I will be adding the renegade to my 84 vette also. I want to see your results with your setup. I have also read that DCS is going to be selling a cam to work with the new intake manifold. Don't listen to the negative comments by former crossfire owners for one, that dominic guy ran a cam that only worked in the low end of the rpm band and died at about 3500 rpm that is why he only got a 13.3 out of his crosfire, I think that with your cam and heads and the renegade you will do much better and if it isn't quick enough just add a 125 shot of NOS and put in some 3.75 rear gears, you will definately be in the 12's. Did you see that article of that crossfire that went 11.8 in the 1/4 with just NOS, roller rockers, rear gears and I think a stall converter.

 

[nelson84]

1984 Chevy Corvette - 11.8s For $2,000- Feature 1984 Corvette

John Wood's 1984 Corvette
By Tony Whatley
Photography by Tony Whatley


When people hear the word "Corvette," many thoughts and stereotypes immediately spring to mind. To some, memories of racing heritage and championship victories are how they define the Corvette; others see them as midlife-crisis status symbols driven by snobby elitists. Even within the Corvette community, there are models looked down upon by owners of other generation Corvettes. There was no '83 Corvette, and in 1984, enthusiasts were eager to see the latest rendition of their beloved two-seater. The '84 Corvette is the first model year of the C4 platform, which carried on through 1996. Although it grabbed the Motor Trend Car of the Year award in 1984, there was little competition in the domestic performance category at the time. From GM, the '84 Cross-Fire injection 5.7L Corvette came with a measly 205hp rating. Quarter-mile ET could be timed with a sundial by today's standards, resulting in mid-15 second passes, and magazine test reports showed a pathetic 7-second 0-60 mph time. Now even family cars with four-bangers could humble this performance vehicle, and many Corvette aficionados refer to the Cross-Fire as "Mis-Fire" because of its unpopular EFI setup, which was only produced for two model years. The more popular TPI and LT1 engines soon followed, starting in 1985, never giving the Cross-Fire much of a chance to shine.
In the July 2006 issue, we brought you four vehicles that ran impressive times on a tight budget. Those cars ran 11s cheaply, but they didn't start with a 15-second car as the platform. This latest installment will provide you with proof of how simple it is to make a V-8-powered sports car run 11s with minimal modifications.
John Wood III of Cypress, Texas, has owned this '84 Corvette for more than 15 years. It was originally his father's garage queen, and he was given the keys at age 16. The car was already 11 years old when John got behind the wheel for the first time, but it has been maintained immaculately its entire 78,000-mile life. Somewhere along the way, John decided the car needed to have performance to back its appearance. This was probably the result of him having 5.0 Mustang buddies back in the day who taunted him with their typical Flowmasters and 3.73 gears. Everyone thinks a Corvette is supposed to be fast, but these early C4 models definitely do not fit that stereotype in factory form. John, along with his father and friends, started tinkering with the Corvette, doing minor things to enhance its performance. The first mods were the addition of 1.6 ratio rocker arms, a homemade cold air intake, and drag radials. This setup produced timeslips in the 14.30 ET range. The addition of 3.73 gears finally got the car into the 13s, but that wasn't quick enough for John. The factory catalytic converter was replaced with a high-flow unit, and the mufflers were bypassed. Next came a NOS brand wet-nitrous kit, specifically made for the Cross-Fire (kit #5125, no longer produced), which was jetted to 125 hp. This combo got the "Mis-Fire" into the 12.50 ET range, and a little more custom-tuning and a man-sized 150hp nitrous jet netted the current best ET of 11.86 at 119 mph with an impressive 1.6 short time. As you might imagine, this car has seen its share of street encounters. Unsuspecting challengers smirk at this stock-looking '84 "Mis-Fire," but are then quickly embarrassed. Recently, the owner of a C5 Z06 was talking negatively about the engine at a car gathering, and was later humiliated by the Grand Daddy C4-in front of witnesses

Amazingly, this car's entire list of modifications costs less than $2,000. The Corvette runs a completely stock long-block (except for the rocker arms mentioned), and the factory fuel system is still in use. The original 700R4 transmission hasn't been touched in its 78,000 miles, and that includes the stock torque converter, suspension, everything.
Considering these '84 Corvettes currently sell in the $4,000-$10,000 price range, you could net an 11-second sports car for the price of a used Honda Civic. It's too bad so many young drivers don't fully realize the true potential of the V-8, and elect to roll around in stickered imports instead. Luckily for John, his father steered him in the right direction at an early age by introducing him to Chevrolet performance. He has since owned quite a few LSX-powered vehicles, but this Corvette has sentimental value, and will always be a part of the Wood family.

​

DATAFILE 1984 CORVETTECAR1984 CorvetteOWNERJohn Wood IIIBLOCKOEM cast iron L83 5.7LCOMPRESSION RATIOOEM 9.0:1HEADSOEM cast iron, unportedCAMOEM hydraulicPUSHRODSOEM ROCKER ARMSCrane 1.6 roller tipPISTONSOEM cast aluminumRINGSOEMCRANKSHAFTOEM 3.48-inch stroke, cast steelRODSOEMTHROTTLE BODYOEM dual TBI RochesterFUEL INJECTORSOEM dual Cross-Fire injectionFUEL PUMPOEM in-tank electricalIGNITIONOEM HEI with Mallory wiresENGINE MANAGEMENTOEM with custom chipPOWER ADDERNOS wet kit #5125JETTING150 hpEXHAUST SYSTEMY-pipe, muffler delete, high-flow catTRANSMISSIONOEM 700R4TORQUE CONVERTEROEM 3,000 rpm stallDRIVESHAFTOEM aluminumFRONT SUSPENSIONOEM mono leaf with upper/lower A-arms REAR SUSPENSIONOEM mono leaf with upper/lower A-armsREAR ENDOEM with 3.73 gearsBRAKESOEM 11-inch discs front/rearWHEELSOEM 16x9.5 front/rearFRONT TIRESFalken 255/50-16 radialsREAR TIRESBFG 255/50-16 drag radialsFUEL OCTANE93RACE WEIGHT3,267 lbs with driverBEST ET/MPH11.86 at 119 mphBEST 60-FT TIME1.60CURRENT MILEAGE78,000MILES DRIVEN WEEKLY30

 

[Cartrax]

Thanks man, I'll have to read all of this later when my wife isn't around. If she walks by and sees your avatar she'll think I'm on a porn site again.

 

[nelson84]

Thanks man, I'll have to read all of this later when my wife isn't around. If she walks by and sees your avatar she'll think I'm on a porn site again.

Geez, its just my wife in the avatar. You should have seen the old picture of her in my avatar, they made me change it, only thing covering them were her hands.

 

[Cartrax]

Geez, its just my wife in the avatar. You should have seen the old picture of her in my avatar, they made me change it, only thing covering them were her hands.

That's funny. Lucky you. Thanks for the information. Reading now - at work. (Actually, I think I did see that one.)

 

[Cartrax]

Read it, good article. Thanks. I agree - no reason why you can't have a hot CFI, especially if a carbed "84 can be hot. I'd rather have the CFI set-up. Mine should be pumping about 1,500 cfm when were done. Just need to make sure it gets consumed properly.

Actually, I found out it's about it's less than half of the 1,500 CFM for those of you who thought this was a bit off, you were right. I thought each TBI would be putting out about 750. I was told both combined may get you near 700.

 

[toobroketoretire]

CFI Throttle Bodies

DCS flow tested various bores of throttle bodies and published their results recently:

1.80" bores flowed 567 cfm

2.00" bores flowed 719 cfm

2.13" bores flowed 773 cfm

So the stock 1.80" bores will handle the air flow needs of most 350" street engines.

 

[Buccaneer]

DCS flow tested various bores of throttle bodies and published their results recently:

1.80" bores flowed 567 cfm

2.00" bores flowed 719 cfm

2.13" bores flowed 773 cfm

So the stock 1.80" bores will handle the air flow needs of most 350" street engines.

Actually we didn't "publish" these results. They were sent to pre-buy people for their own use for tuning purposes if needed, not for the general public as stated in the email we sent to you and everyone else. Again, you've lead the way. ad This stuff isn't free for us when we use a flow bench to get these results you know. Enjoy!

 

[VIN_#_00521__Z-51_C4]

Hey Whats up did you mount that emblem yet whats the progress on your renegade ?

 

[nelson84]

Hey Whats up did you mount that emblem yet whats the progress on your renegade ?

Are you talking to me? I have not mounted that emblem yet, will after I install my renegade.

 

[Cartrax]

Ditto, what Nelson said.