Question about Howell conversion.

[esc]

>If your talking about wanting to run a 4 barrel TBI, the only gm ecm I know
>of to do that properly is the 1227749 wired as used in a 87 Sunbird Turbo.
>  In some testing that I did, I was unhappy with the results of firing
>injectors wired, in series parrarel.
>  If you want to run a 4 barrel TBI, my suggestion is to run, a TBI ecm and
>then make an injector driver board external to the ecm, to actually fire the
>injectors.

Sounds like a can of worms I'de rather not open.

>  From what I've heard all the 4 barrels use the same butterflies, but
>different injector sizes from rating to rating.   So the idea of selling
>them by CFM is silly, when they all flow about the same CFM, and the actual
>difference is gals/hour....

Mine is the 900CFM..uh, 4 85 lb/hour injectors.  Holley claims it is good
for 500 HP at 15 PSI.

>  Next item, 4 ninety gal/hr injectors would support about 700 HP.
>  I run 13s in a 3000#/350 CID car, with 2 two inch butterflies, if you
>really need that much air (4-2" butterflies), I'd look further than a TBI...

I want to use my TBI because I put a lot of effort into the ram-air system
on the car.  If I go with a port injection system (most anyway) I would
have to scrap my ram-air, and maybe my hood.

>  If your needing that much air, then you have a bunch of cam, and might do
>well using a 747 where you can go open loop at idle.

I do have a lot of cam 255 at 0.50 and 0.600 lift.  Would I need the
external driver board you mentioned earlier to use the 747?

>Cheers
>Bruce

Eric
esc at firstnethou.com
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