I bought a Holley 700cfm 4bbl TBI (with injector pod but no injectors) that I plan to use as a throttle body for mpfi. However, I may use it as it for a tbi if I can use stock type tbi injectors. I'm not sure what type of ecm I would use to control it though.

Can stock injectors be used in the pod? I believe I have the old style injectors that are top fed.

Thanks,
Chris

 

You can run the 4 injectors off the 2 controllers but they'll see half the voltage. Do a search on 4 bbl tbi and my post should show up from within the diy-eprom board.
The major problem is that with the 6 volts the injectors have a hard time holding open so you'll notice big problems with the injectors getting flaky above ~3000/4000rpm. You can still run it but it's best to build an add on injector control board. I doubt you're going to do it but if you want the schematic it's on the diy-efi.org webiste on the ftp server.

 

maybe some v6 injectors will work in there.

 

My biggest question is: will GM injectors work in the Holley 4bbl (top feed style) pod? I may have to ask Holley.

I did do a good bit of research and saw the extra injector driver board schematic. It's all greek to me, so when I go to use the 4 bbl tbi I'll most likely get a Holley 950 engine management kit. It will either be the 950-100 which converts the older ProJection tbi or the 950-109 to use the tbi unit (with a mpfi intake w/ injectors) as a throttle body. Doug did this using a converted intake (see the post "Single Plane EFI >$1000).

What I'm doing right now is converting my Malibu to a stock type tbi using the 454 tbi I just acquired. I'm doing this for better mpg and to learn about FI with the stock type system. So far I have the tbi, harness (needs to be repinned), two 7747 ecms, and the Holley adaptor. This weekend I'm going to pick up a FI type fuel tank with sender and pump.

Thanks for the input!
Chris

 

Chris, I can tell you now that the GM injectors won't fit in a holley pod be it 2 or 4. I can also tell you that the newer Holley injectors are actually GM units so that's good news. They aren't exact GM injectors, I think Delco or Delphi is the company, not sure, but they make the injectors for Holley. The older Holley in house injectors were crap but I believe for at least a year now they've all gotten the better injectors.
The 950 is an awesome system. I wish I could afford it .
Definatly spend the majority of your time over on the diy-eprom board. Grumpy, myself, and a few others are always the guys that reply to TBI tuning be it the 7747 or 8746 ecm.

 

Chris, I can tell you now that the GM injectors won't fit in a holley pod be it 2 or 4. I can also tell you that the newer Holley injectors are actually GM units so that's good news. They aren't exact GM injectors, I think Delco or Delphi is the company, not sure, but they make the injectors for Holley. The older Holley in house injectors were crap but I believe for at least a year now they've all gotten the better injectors.
The 950 is an awesome system. I wish I could afford it .
Definatly spend the majority of your time over on the diy-eprom board. Grumpy, myself, and a few others are always the guys that reply to TBI tuning be it the 7747 or 8746 ecm.