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Converting 2 bbl carbarator to throttle body

  
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Converting 2 bbl carbarator to throttle body

 
Xcarguy08 Xcarguy08
New User | Posts: 1 | Joined: 02/12
Posted: 02/20/12
09:31 PM

i have 1977 GMC Sierra with 305 V8 and a Rodchester 2bbl. It runs very cold and with 3speed on tree it requires more downshifting that normal to maintain RPM's. I want to covert to throttle body, but which one. I presume the Tbilisi on 1987 305 V8 would be closest match, but just guessing. Any ideas as to how to proceed?  

460-BBF-Turbo-In-CC 460-BBF-Turbo-In-CC
Guru | Posts: 1163 | Joined: 10/03
Posted: 02/21/12
08:09 AM

Head to the u-serve salvage and start measuring throttle bodies.  There used to be a company called "Turbo City" that sold a lot of conversion parts.

A while back, Hot Rod put TBI off of a Mopar on a Maverick 6 and then blew the whole thing up with N20. So it's mostly a matter of getting a good used TBI and rigging up the lines and electric pump.

An '80s TPI system would probably be a better swap though, if you can find one on an old F-Body or Corvette.  The longer runners will pump out more torque than a TBI system  
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460_BBF_Turbo-in-CC (formerly Dr511scj) "This guy has no life other than posting endlessly on carcraft.com." -- Car Craft, July 2005
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October 1, 2003: " I'm thinking a couple of...turbos, blowing through an old Powerstroke intercooler...on a Super Cobra Jet-head 460 would be mad cheap and make sick power."
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waynep7122 waynep7122
Enthusiast | Posts: 594 | Joined: 08/09
Posted: 02/21/12
09:55 PM

305 TBI will work..

there are adaptors to mount the 305 throttle body on the early intake...

there is things that you might need to know...

the TBI intake is different in that there is a BIG coolant passage under the plenum .. to warm the incoming air and fuel to stop it from puddling..

you might get along with a straight conversion..   and it will probably work just fine...

be sure that you check the small Cap HEI distributer..  for cracks in the layer under the reluctor.. that will give you headaches..  reman small cap HEI distributers are available and work far better than a worn out original..  cleaner signal to the module..  

please.. plan on installing the oxygen sensor .. as these systems DO NOT WORK WITHOUT an oxygen sensor to feedback during closed loop operation to fine tune the fuel mixture..

TBI and TPI intakes are also usually equipped with a slightly different intake bolt pattern...

where the first two and the last two intake bolts are at the same angle and location.. the center two.. on either side of the exhaust crossover are angled upward slightly...

there are also a BUNCH of new self tuning fuel injection systems available now..