During the resto of my CFI 83 Z28, I want to keep the CFI setup and functional hood, but I want as much power as I can make while keeping a mostly stock appearance. Can anyone give me any suggestions? Here's what I thought of off the top of my head:

1) 350 based motor instead of the 305. Maybe a stroker?

2) port the intake and the heads. Aftermarket heads? Stock heads?

3) hotter cam, though I have no idea of the specs that would suit my needs.

4) custom chip for the ECM. Will the 305 ECM work on a 350 if I get a custom chip burned?

5) headers. I'd like to keep the emissions equipment in place to maintain a stock appearance, though. I can run without cats as the car isn't required to be emissions tested anymore.

What else? Anyone out there have any success stories? The car will be street driven, though I'll probably throw some stickies on it and take it down the strip a few times. I'd be comfortable with anywhere from 3:08 -3:73 gears and up to a 3,000 stall converter or so.

Thanks for the help.

 

Crossfire Injection Forum is the place to do some research.

I dont believe the heads are worth porting. World and Dart make some good inexpensive iron heads.

Dont think a custom chip is in your best interest. You will be better served doing the burns yourself. You will need to swap out the ECM to another. There is no support for your 5550 ECM. Also the new ECM will need to be adapted to your stock wire harness(speedtronics.net). The connectors are different.

 

Thank you. I'll check that out. Any idea what ECM I'll need?

 

Most common choice is a 7747. Or a 8746. But there are other choices as well. I chose an EBL (aftermarket ECU). See dynamicefi.com.

Before you dive in do a lot of research.

 

83 crossfire, I never seen one got any pics?

 

As Ronny suggested do a lot of research before you dive in - perfect expression. On porting the intake it would be in your best interest to get and extra base to be on the safe side. You will be removing a lot of metal just from the intake ports (if you've had your intake off or seen pictures you understand).

Another area to keep in mind is exhaust. You will want to use the exhaust intended for a L69/L98 as they are the best systems. And this is the same whether you use factory manifolds or headers. The TBI units can be bored ,the top plate ports are 52mm, but 50mm is really the most reasonable.

Check out the links below for further info.

Upgrading the intank pump to an '85 TPI pump will provide more consitant ,plus higher, fuel pressure. The factory states the system is happy with the 9-12psi the stock pump delivers but even a stock motor runs better at 14 to 18psi. The stock regulator can be made adjustable.
http://www.corvettefever.com/techart...ing/index.html
http://www.crossfireinjection.net/
http://web.telia.com/~u60113744/soft...dl/winaldl.htm
http://www.technovelocity.com/chevyh...rt_polish.html

http://www.x-ram.com/commonproblemsw...onsystems.html

 

This is in about 1989 or so...before I sold it.

 

Thank you for the awesome info.

Am I a fool for wanting to build up a CFI setup? The thing that hooked my dad on the car was the functional hood, and I really want to keep that. I'm not worried about having a pump gas, 10 second street car or anything. Just something that'll light the tires and be fun, yet reliable.

 

The main problem found on the crossfire injection systems are leaky throttle shafts. Yep same as our TBI setups... Fuel pressure below 14psi is an issue. I agree that CFI systems function better at or slightly above 14psi.

You can have the throttle bodies bored and re-bushed. Send your injectors off to have them ultrasonically cleaned and flow tested. Once you find the flow rate of each one it will be easier to determine if you want to spend the money on new injectors or not. Flow testing will allow you to determine what your horsepower capability will be with "stock" injectors and stock fuel pressure.

I'd upgrade the fuel pump for sure with ANY modifications that you do.

If you need the overhaul gasket/o-ring kits with the dual regulators let me know. I have plenty of them. I also have the IAC Valves and throttle position sensors.

Good luck and keep us informed

 

Crossfires were found in:

1982-1983 Camaro and Firebirds. 5.0L
1982 & 1984 Corvettes 5.7L

 

Any updates?

 

How is the build coming along?

 

How is the 350cfi build coming along?

 

That was 6 years ago, and he hasn't been online since 2011, that's almost another 5 years ago. I doubt it ever happened.