[Gmecm] TBI conversion

[Jake Tucker]

Bob,
	Just a few other tidbits I've learned from several conversions
(two TBI's, one TPI, and two vortec's, also two Holly Pro-jections :( ).
	You can use the stock intake instead of an adapter, but the
middle intake holes are at the wrong angle, and require a bit of work
with a grinder.  It doesn't look pretty, but it will work.  You're
better off using the adapter as stated in earlier e-mails.  Also, the
stock intake is known to crack.
	The painless harnesses are definitely easier.  However, they are
not for the budget conscious, and if you have a wiring diagram for the
TBI system, it's not too hard to convert a stock harness with a little
time and effort.
	Make sure you have an adequate alternator.  The stock ones from
a '69 vette don't provide enough juice, and it's best to upgrade to a
newer system.  The best choice is to get the entire serpentine setup off
a late model truck.  In fact, I have a friend with a complete serpentine
system off a '95 Chevy Truck including A/C.  We replaced that motor with
a vortec one.  He has the '95 harness, but it doesn't use the 747
computer, and the stock '95 computer was fried.  The '95 harness is
pretty stand-alone also, and would be nice for a retrofit since it has
an under-hood fuse and relay box.
	In my opinion, the biggest pain is the fuel system.  You will
need a return line to your tank, and provide a high pressure fuel pump.
I prefer to use a stock injected fuel tank, with the stock in-tank pump.
You can use an external pump, which is considerably easier, but they're
also more expensive, and noisier.  You will then have to work with fuel
lines.  The throttle body will have brass colored adapters that connect
to a special flare nut that I've only seen on GM fuel lines.  Some early
Cadillacs, which use the same throttle body, have a brass colored
adapter that connects to a standard inverted flare.  I don't know which
year, I just know that I found one in a junkyard once, and grabbed it
before I knew how rare it was.  On the fuel pump side, it will use the
same GM fuel line flare.  The supply line will be 3/8", and the return
will be 5/16".  From the throttle body to the frame rail, you can get
the stock unit, which will have the proper bends to drop the fuel lines
from the throttle body to the frame rail.  From there, you can use a
chunk of stock fuel line and cut it off and use a compression fitting to
connect it to some standard 3/8" line.  Remember to use a high pressure
fuel filter on the supply side at this point.  On the fuel tank side, if
you are using a stock tank, you can get some flexible fuel lines to
connect to the tank, then use some stubs from a stock fuel line and
compression fittings to get to the frame rail area above.  Most GM
vehicles used the same fittings in the late 80's and early 90's, so just
look for two rubber hoses (one of each size) that are long enough for
your installation.
	With the TBI system, the cam may be a slight issure, but if you
have a good idle at 800 RPM, it should be O.K.  You'll definitely need
to do some tuning, but there is a lot of expertise for that in this
forum.

Jake Tucker

-----Original Message-----
From: gmecm-bounces at diy-efi.org [mailto:gmecm-bounces at diy-efi.org] On
Behalf Of BNRVL at aol.com
Sent: Thursday, November 30, 2006 7:43 AM
To: gmecm at diy-efi.org
Subject: [Gmecm] TBI conversion



  Hello , I have a print of an  article from  January 1994 issue of
Street 
Rod , written by Doc Frohmader who  outlines some details for  a Low
Budget 
Injection system for Mike Moeller's 1939 Chevy Sedan .

 The parts are from a 1988-92 Chevy Truck , salvage yard variety . I
want to 
follw this recepie for my 1933 Dodge Pickem-up Truck .It has a 1969
Corvette 
350 CI engine ,Sig Erson can, numbers unknown but a nice  smooth
800-1000 rpm 
idle , factory alum intake ,  Carter 4 Bbl. carb. 350 automatic trans..
and at 
3500 rpm it will jump one lane when opened up to 4200 rpm , so I do not
need 
any more speed for a daily driver , just improved gas mileage which now
is 15 
mpg highway .

 Ihave not been able to locate an email for Mr. Frohmader nor Mr.
Moeller , 
so a follow up for current info on the project is not possible as of
today .

  Can any one help me  ?, in  that I am ready  to begin  a parts list
and 
begin to accumilate  pieces for this endeavor  now. 

 Thank you

 Bob Norville
  Memphis,Tn. area
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