Although I feel port injection is the
> ultimate, the biggest draw back to me is justifying the cost vs. TBI and
its
> benefits
I've given this a little thought myself. 'Way back 25 or so years ago when I
first began seriously studying and restoring Corvettes, I was fascinated by
the Rochester RamJet fuel injection system that first appeared on the '57
Corvette and was available through the early '65 models. I well recall
reading interviews with Zora Arkus-Duntov, one of the developers of this
system and widely regarded as the "father of the Corvette." He stated that
their research indicated that a timed, port injected system had the
advantage of slightly better fuel economy, but that the constant flow
system, which the Rochester was, yielded slightly better performance. As I
recall, Mercedes was working on a mechanical timed system which saw
production, but I know nothing about it. The Rochester system, with which I
am very familiar, is a marvel of design; it is quite simply a mechanical
analog computer. It was extremely efficient and quite reliable if left
alone; unfortunately, hordes of tinkerers decided it was junk, so they
didn't have the reputation they deserved. Probably some parallels in the GMC
world.
Of course nowdays digital electronics has changed everything. What used to
be very hard to do with any precision is insanely easy...everything from
adding machines and typewriters to alarm clocks have benefitted or been
replaced. Fuel injection is no exception. But I wonder if the same
principles--that is, timed port versus constant flow--have changed? TBI
(Throttle Body Injection) is very easy to implement, since it is essentially
a replacement for the carburetor. Chevrolet even used an adaptor plate to
mate the two-barrel throttle body to the Quadrajet intake on the late 80's
454; this is readily available and would make it easy to put TBI on a GMC.
But there are also companies doing some pretty elegant retrofitting by
drilling the ports and installing mounting bosses for port injection.
I would like to see someone make a stab at researching this and reporting
the findings; frankly, it is completely out of my league time- and
money-wise these days. I would refer you to www.tpis.com and to
www.fuelinjection.com as both are very much into this. Fuelinjection.com has
several pages of interesting explanations of the components and
terminology...good reading for everyone.
Best regards,
Travis in Lubbock, Texas
> ultimate, the biggest draw back to me is justifying the cost vs. TBI and
its
> benefits
I've given this a little thought myself. 'Way back 25 or so years ago when I
first began seriously studying and restoring Corvettes, I was fascinated by
the Rochester RamJet fuel injection system that first appeared on the '57
Corvette and was available through the early '65 models. I well recall
reading interviews with Zora Arkus-Duntov, one of the developers of this
system and widely regarded as the "father of the Corvette." He stated that
their research indicated that a timed, port injected system had the
advantage of slightly better fuel economy, but that the constant flow
system, which the Rochester was, yielded slightly better performance. As I
recall, Mercedes was working on a mechanical timed system which saw
production, but I know nothing about it. The Rochester system, with which I
am very familiar, is a marvel of design; it is quite simply a mechanical
analog computer. It was extremely efficient and quite reliable if left
alone; unfortunately, hordes of tinkerers decided it was junk, so they
didn't have the reputation they deserved. Probably some parallels in the GMC
world.
Of course nowdays digital electronics has changed everything. What used to
be very hard to do with any precision is insanely easy...everything from
adding machines and typewriters to alarm clocks have benefitted or been
replaced. Fuel injection is no exception. But I wonder if the same
principles--that is, timed port versus constant flow--have changed? TBI
(Throttle Body Injection) is very easy to implement, since it is essentially
a replacement for the carburetor. Chevrolet even used an adaptor plate to
mate the two-barrel throttle body to the Quadrajet intake on the late 80's
454; this is readily available and would make it easy to put TBI on a GMC.
But there are also companies doing some pretty elegant retrofitting by
drilling the ports and installing mounting bosses for port injection.
I would like to see someone make a stab at researching this and reporting
the findings; frankly, it is completely out of my league time- and
money-wise these days. I would refer you to www.tpis.com and to
www.fuelinjection.com as both are very much into this. Fuelinjection.com has
several pages of interesting explanations of the components and
terminology...good reading for everyone.
Best regards,
Travis in Lubbock, Texas
