How about putting a 454 TB on a EFI port injection aluminum intake manifold.

Bob Dunahugh

New member
Sep 17, 2012
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I have an aluminum port injection manifold with all related parts on it. So strip it down. Some modifications. And put the 454 TB on it. Any thoughts?

Bob Dunahugh 78 403
 
> I have an aluminum port injection manifold with all related parts on it. So strip it down. Some modifications. And put the 454 TB on it. Any thoughts?
>
> Bob Dunahugh 78 403
> _______________________________________________

Sounds like weeks of work and then you have to hope the fuel map works
reasonably well on a 12,000 motorhome.

Kelvin
'73 23' in Eugene, OR with most of a FiTech TB installed in 10 hours...
 
Sounds like a great experiment if you have the time to futz around with it and don't need to take any long trips in the GMC anytime soon. Tuning that
setup could be instant gratification or a nightmare that lasts and lasts. Why not try your 454 throttle body injector on the stock manifold to see
how well your pump/throttle body/engine combo works together. Or sell that manifold to a hot rodder that wants a port setup before you have to make
any irreversible changes to it and apply the funds to the FiTech setup. Several GMCers will have plenty of installation advice :)
--
Terry Kelpien

ASE Master Technician

73 Glacier 260

Smithfield, Va.
 
> I have an aluminum port injection manifold with all related parts on it. So strip it down. Some modifications. And put the 454 TB on it. Any
> thoughts?
>
> Bob Dunahugh 78 403
> _______________________________________________
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If I remember the factory 403 port injection manifold was a very open design with no runners like a tbi or carb manifold has. They didn't have to try
and get equal fuel distribution as the injectors at each port took care of that. No provision for manifold heat either. That said why not go
multiport? EBL would control that in batch fire and tune itself. You could still use 454 TB as an air valve and use its idle air control and throttle
position sensor, just omit the injectors.
--
Wally Anderson
Omaha NE
75 Glenbrook
Megasquirt III injection
Bob Stone hydroBOOOOST
Manny reaction arm system
Branscombe Kelsey Hayes park brake
http://wallyandsue.blogspot.com/
 
Well it seems that no one has tried it. And there are air/fuel issues. So it seems that putting that 573lbs iron intake manifold back in place is what I need to do. Or is it 673lbs of iron?

Bob Dunahugh 78 403
 
I'm putting a 76 iron intake and large bore throttle body on my 77 403. It will be controlled by a FAST multiport controller with dual sync
distributor. It's been in process for a while but I hope to have done next year. The intake and throttle body came off a 76 seville. The throttle
body is identical to the cadillac 500.
--
Jerrod Winter
1977 Palm Beach
Green Jelly Bean
Twin Cities, Minnesota
 
So you have the port injection manifold, correct?
Put in a 3.70 final drive and it should perform well.

> I'm putting a 76 iron intake and large bore throttle body on my 77 403.
> It will be controlled by a FAST multiport controller with dual sync
> distributor. It's been in process for a while but I hope to have done
> next year. The intake and throttle body came off a 76 seville. The
> throttle
> body is identical to the cadillac 500.
> --
> Jerrod Winter
> 1977 Palm Beach
> Green Jelly Bean
> Twin Cities, Minnesota
>
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> GMCnet mailing list
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--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk
http://www.appliedgmc.com
1-800-752-7502