performance upgrades

[howes maryjane]

It's time to do performance upgrades on my '77 GMC w/455 (92k on
probably original engine)equipped with thorley headers & jardine free
flow exh. system. I'm considering jacobs Ceramic 2000 plug wires along
with other ignition components from jacobs. Also thinking of replacing
original carb. with late model GM throttle body injection system as well
as serpentine belt conversion. Anyone have experience with above
upgrades or pitfalls to watch out for? Thanks for your time.

 

[thomas g. warner]

I have heard others wanting to go with the serpentine belt system but really
can not understand what you are going to gain for the money. Belts are
cheap and easy to replace. Have thought about fuel injection also but
wonder if it is an improvement over the rochester. The beauty of the 455 is
that it is bullet proof and simple to tune up and maintain, and can be
worked on anyplace. When one starts adding computers, proprietary belt
systems etc to an already simple engine, are you going to really gain
anything for the large expense, other than something more difficult to
maintain?

I just checked everything on my engine, shows 70,000 miles and do not know
if it is original or not. Compression still 165#, but ticking noises in
right cylinder head. I thought it was valve lifters, but fortunately talked
to a very experienced mechanic that used to work on 455's and he told me
that rocker pivots were worn. Replaced them ($16.00) installed new Felpro
valve cover gaskets. I opted for a remanufactured rochester carb ($234.) and
now runs like new, lots of power and very quiet. Also installed new Beldon
700241 wires ($46.00), AC Delco R46SX sparkplugs, all available from my
local parts dealer.

>It's time to do performance upgrades on my '77 GMC w/455 (92k on
>probably original engine)equipped with thorley headers & jardine free
>flow exh. system. I'm considering jacobs Ceramic 2000 plug wires along
>with other ignition components from jacobs. Also thinking of replacing
>original carb. with late model GM throttle body injection system as well
>as serpentine belt conversion. Anyone have experience with above
>upgrades or pitfalls to watch out for? Thanks for your time.
>
>

 

[robert m fukumoto]

- ---------
From: Thomas G. Warner
Sent: Monday, May 18, 1998 2:59 AM

. I opted for a remanufactured rochester carb ($234.) and
now runs like new, lots of power and very quiet.

Thomas

I bought a 76 Palm Beach that had a car carburator in it and
it resulted in a burned valve because it ran too lean. When
I looked into a rebuilt GMC motorhome carb it was really
expensive. I had all my engine work done by Darrell
Winterfeldt, a top notch mechanic, and he found me a used
motorhome carb and rebuilt it. I'd be real careful on the
carb that you bought for $234. Cinnebar was looking a
remanufacturing the motorhome carb and was talking in the
range of $1000.

Bob Fukumoto