I know that maybe this question have been up earlier, but I am unable to find a good answer on this. I have a 454 engine, which I plan to rebuild with ovalport head and are aiming for ~500 hp. I have an idea to use Edelbrock manifold for dual 4bbl but instead run dual TBI 2BBL units. The modification that I wonder about is to use dual TBI. I have noticed that Dynamic EFI can add "The 4 injector driver upgrade" to my box and I will then be able to run 2 TBI units. Do you think that this will work? Is this a good idea or should I instead go for Performer RPM Pro-Flo EFI # 3551? Anybody which are running big-block with modified TBI according to Dynamic EFI and can tell me if this is a good idea?

I say go for it man, that sounds awesome to me. Sounds like fun and it's quite an interesting idea. It'll work but it will take a lot of tuning to get it right. Jump in man! If you have the original 454 TBI and plan on using something else, let me know. I think I could give it a good home!

If you 496 your 454, you should reach ~500 hp at a reasonable rpm.

Single TBI may have difficulty with narrow pulse widths at idle unless you use a cam with a wide LSA (with low overlap) so your vac ref fpr will have a wider range from idle to WOT.

I would say the dual TBI would work great.

Do it!

Thanks for your encouraging words. I really think that this is a good idea.
I can keep original ECM and the car should work as pretty stock.

But the main question is:
Is it possible today to run with dual TBI?
Before Dynamic EFI is have not been possible, to my knowledge, but I need someone who have tested this and can testify to me that this is what the modification of the ECM that Dynamic EFI is doing.

Because if it is -> we are home safe.

The streetracers here (in Sweden) are telling me that it is a peace of cake to get +500 hp from a pretty plain 454 if you chose the correct cylinderheads and the correct cam.

It is possible you just have to add either a transistor with higher amperage capacity to the injector driver circuit or build an "piggy back" peak and hold injector driver. Talk to HaulinA$$, he was running a 4 bbl Holley TBI unit on his stroker engine with nearly that much power.

Mercury Marine had a 2 TBI big block a few years ago that made something close to 600 HP with a blower IIRC.

No, it has been done before. The schematic for altering the ECM with a 2nd set of drivers has been posted on TGO before.... and there is at least one vendor that sold it commercially... as well as the marine big block that used 2 GM TBI units atop a blower (500 shaft hp, very conservative set up). Do an advanced search on this forum.

NOW with Dynamic EFI, you can do it more easily, and more easy to tune. You need to read the threads on ECM PROM to get familiar with it.

I wouldn't say that (pretty plain) because it's still over 1 hp per cubic inch. I'd say a moderate cam plus slightly ported heads + excellent tuning. AFAIK no one has yet used it on a bbc.

BTW you either must know, or should get to know, Anders (aka Bostic on the Impala SS forums) given the car you have and where he's located:

http://www.blackout.nu/

He's also in Sweden.