1028...EFI Question #2

Why do you like the analog efi better? Also, if it is analog how does it incorporate an O2 sensor and a CPU? I don't know aftermarket efi's only enough about the stock ones to diagnos and fix them. Thanks is advance.

The Pro-jection set up is a self supporting unit with it's own control computer. The newer ditigal ones actually work better but they are expensive and you need a laptop to set them up and make changes. The older analog ones are now cheaper ,because the racing guys want the new trick stuff, and they can be set up manually ( seat of the pants ). M1028

Thanks.

ahhhh BARRY is that a 4di? if so it's still digital but w/out all the tuneability of the laptop deals. You tune yours right from the CPU if I remember....
In my opinion guys like us don' t really need all that extra tuning anyway. I basically want a fuel injected carb that will just work. Tune it like a carb and leave it be lol... OH hey how's that working in the colder weather?

The added tuneability is something I think I need to keep in mind for the future. Going from a small engine to a large, um stupid engine may need some tuning that the analog won't be able to accomplish. Eh, we'll see.

The 4di is digital and you need a laptop. I use the older analog system that is tuneable as you drive . It does need adjusting from time to time. Especially after about a 20 degree change in temp. M1028

I've never been too impressed with the Holley ProJection. Tman was running it on his SBC and it seemed when it was adjusted perfectly for wide-open mid-rpm operation it would load up and hesitate at lower RPM & load situations. The simplified adjustments on the ProJection just don't give you enough "fine-tunability." They also make the assumption (like a carb does) that the engine's fuel needs are linearly proportional to RPM and load, which is usually not the case. That's why if you look at a fuel map for a OEM efi system (be it GM, Ford, whatever) you will see the map doesn't look like a smooth ramp up but has lots of little dips and valleys along the way.

I'm also not a fan of TBI at all. Suffers from the same poor atomization and uneven delivery as a carb. Only benifits over a carb are no float bowls and no jets/pumps to adjust. Multi-port is the way to go. Aside from better power AND fuel economy, you get the benefit of redundancy: if you lose one of the TBI injectors, odds are the engine will barely run or run so lean you damage things, but if you lose a multi-port injector you lose ONE cylinder (completely) and limping home on 7 of 8 is usually not a problem. Just my opinion. Incidentally, thats one of the main reasons I went with a 460 and not a 454 -- back then the 454s were TBI. I couldn't give a crap whether it was a Ford or Chevy.

While I'm at it, I would also recommend staying with an OE EFI setup if at all posible -- ie. GM, Ford, Mopar factory injection -- and having it retuned for your particular setup. If you are running a Ford motor, you can run the Mass Air setup from a 5.0 Mustang on just about any Ford V8 as long as you can get a TFI-IV distributor for the motor and can mount the injectors to the intake. The stock programming on the Mass Air 5.0 computers will usually adapt to the engine and work fine 99% of the time so long as the MAF (mass air flow) sensor, injector size and computer are properly matched. However, retuning those computers is easy, too, without having to burn chips using a product called a "twEECer."

I agree with you on the multi port being the way to go. I know of several guys that do have problems with the Pro-jection, But mine just seems to works great. Multiport is also alot more $$$. The 900 set up that I have on my mud truck (with closed loop ) I got for $450.00. That guy sold it to me because He could never get the truck to start !!! It was on a 460 Ford truck. M1028