350 Chev to 400 Small Block

[Bruce Plecan]

-----Original Message-----
From: David Sagers <dsagers at ci.west-valley.ut.us>
To: DIY_EFI at efi332.eng.ohio-state.edu <DIY_EFI at efi332.eng.ohio-state.edu>
Date: Friday, October 30, 1998 7:02 PM
Subject: 350 Chev to 400 Small Block


>Looking for someone with experience modifying and setting up a TBI fuel
injection system.
>I am replacing the tired 350 engine in my ¡92 Suburban w/TBI.  Instead of
going back to the stock 350, I want to install a small block 400. I¢ll also
add a few extras like better flowing heads, a mild cam, headers and a free
flowing cat and exhaust system.
>
>This combination will require more fuel than the stock combination. Small
block 400 have been around for many years and I¢m sure someone has done all
this before, and since I don¢t want to re-invent the wheel, I¢m looking for
information about how to feed this engine and how to get the fuel mixture
correct so its not running rich or lean.
>
>Some of the options available are 1) Turbo City offers high flow throttle
bodies, high flow injectors and computer interfaces to make the speed
density system work with a cam that has longer duration than a stock cam.
Do I just add all their high flow stuff and hope it's close?
>
>2) Edelbrock sells a complete, tunable TPI system to replace the factory
TBI, cost is $1200.
>
>3) Several companies offer computers that intercept the computer signal and
modify the fuel and timing curve according to adjustable settings.
>
>Finally, 4) New chips for the factory computer are available from after
market performance companies to compensate for the bigger engine.
>
>Anyone out there been through this before? What works and what doesn¢t?
Thanks in advance.
>