I'm running right now a 91 camaro with an L03 tbi unit right now. I've got the edelbrock tbi intake with the 1-11/16 bores. I just picked up a holley 502-6 tbi unit with the 2" bores and I'm going to bore out the intake to accomodate. I believe the 502-6 has 65lb/hr injectors and i'm going to install the 255lph holley fuel pump. I'm going to do this on the l03 now (unless otherwise recommened) and plan to use this setup on my 383 buildup I'm currently working on. Am I making a mistake going to the tbi or should I go carb? This is going to be a street/show project but I'm still hoping for 350-400HP. I know the 383 can handle it, can the tbi?

Thanks

 

yes it can but, only if you can tune it. Tbi is tough to tune real wild cams and needs tuning for most every upgrade.

Only other problem i may for see is the 65lb hour injecters may bw a little small (might think about 80lb hour big block injecters).

Lastly you may look in to the walbro 255 pump, i'm sure it's much cheaper than the holley and most everyone has had good luck with them.

 

If you are keeping your LO3 fairly stock until your 383 is ready than hold off on the injectors and larger TBI unit. The larger unit will be needed on the 383 and you will more than likely need larger injectors. Your stock LO3 is bottlenecked by the exhaust and cam. The stock unit and injectors are enough to feed your motor. Changing them now, without chip work, will only cause you grief and leave you with a car that runs like poo.

 

Also your 383 will be much more efficient with a TBI than a carb...

 

Define efficient. The VE of the motor, is really going to be determined by MANY factors, the induction STYLE is the least of those.

 

By efficient I mean better throttle response and better gas mileage .

 

The throttle response, and milage, are determined by the person tuning the EFI or the Carb. In either case, it is only as good as the person tuning it. You can get carbs to be very efficient. At the same time, you can make TBI run like poop.

 

Yea youre probably right , I was talking more of stock applications like ''off the shelf'' .

 

Thanks for the input... I'm going to have to check into the tuning aspect. Being an L03 with the roller cam, do you not think that by installing the larger bore tbi unit now would be beneficial? Drop in the fuel pump and change the TB should only increase the airflow into the intake, will this require major tuning?

Thanks again.

 

I would suggest learning some tuning, before you start doing modifications. The big-bore TB really isn't need, until you are making a pretty good amount. I made 230rwhp with my motor, on the stock TB and stock injectors.

 

I've read some of the chip burning stickys but I'm curious about which unit to get. I've got a '91 camaro, l03 with removed smog and a/c. edelbrock tbi intake manifold and stock tb now. headers, shift kit, 3.23 posi and custom cold air intake. msd 6 with msg blaster coil and stock distributor. 6* advance (I believe) and running pretty good with jet chip purhased long before the mods. Which computer do I have and I'd like to get the eeprom chips that can be reprogrammed with different combos. Any suggestions on Wideband 02 vs stock 02 sensor? Should I do this first?

Lots to learn I know but I want to do this right.

Thanks again.