John king 2011-01-30 11:28:58
What are my options on performance upgrades with the TBI setup?
I have a ’94 Siverado 4X4….. do they make aftermarket headers for these?
And if I install a cam or maybe even a set of decent heads, will the TBI
system deal with these mods ok? What about the computer?
Anyone have any history with modifications to this setup?
\doc\ 2011-01-30 11:29:51
Lots of experience with modding this engine/EFI combo. First step is
headers; there are a TON of them on the market, so pick a pair of
full-length (NOT shorties) headers and get a decent high-flow cat and
muffler combo. ECM (computer) will not have a problem with this at all.
You’ll find an extra 20HP here.
Next step up would be a set of cast iron Vortec Heads ($259 each brand
spankin’ new) and a GMPP TBI intake manifold (another $250) to fit the new
heads and TBI unit. That combo will net you 20-40HP, and might require a
PROM reflash for the newer heads.
A cam would be great at the same time you did the heads, and will also
require a PROM reflash. Doc
John king 2011-01-30 11:30:19
Good deal DOC, thanks….. I’ve been checking out some headers online but
have only run across “shorties”. Any idea where to look for a set of “Full
lengths”? And do they make a dual conversion kit? I heard that Flowmaster
made one for the CK series pick-up but haven’t seen them yet…….
I’m also considering maybe just buying a stock 5.7 crate motor and adding
about a 480 lift cam (maybe not quite that big)
Bret chase 2011-01-30 11:30:21
Flowtech Afterburners… they’re under $200 for non ceramic coated
headers, an additional $100 for the Y pipe. you can get them from
Jegs, summit, JC whitney.
not one that’s legal for on road use as the TBI motors all had a
I heard that Flowmaster
a true dual or a split after-cat system? if you’re just looking for a
split system, everyone and their brother makes one.
John king 2011-01-30 11:30:39
a true dual or a split after-cat system?
True dual…….not cat-back.
Cabopeter 2011-01-30 17:50:22
I have done a lot of research on the TBI COMPUTER match, I have put
in a Comp Cam made for TBI , shorty headers, years ago a HyperChip,
free flow exhaust. I am very happy with these mods, there have been no
problems at all. I am going to the Edelbrock Aluminum heads and intake
next. The rings never seated in, so a good reason to put in the new
parts. I am hoping with all these mods to increase the HP from stock
by about 60 to 70 HP. The tranny has a shift kit and the rear end now
has a new posi.
I still have not got a yes or no from the group, on whether I will
have to do a chip change again. I will keep you posted, on that
subject. I am hoping that these are not to drastic of mods for the
computer to keep up with. If I need more fuel, may work on the stock
If any one has done these mods and have had to change the chip please
let me know.Also do a search on this site on “TBI-computer” and you
will find about 30 posting on your questions.