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Hi,
I am looking to add horsepower to my 1978 T/a. I know that stock it didnt
have much. It has the 400 engine. I have put new spark plugs in and new
wires. I dont have headers on there now, but i do have dual flowmaster
exhaust. Any suggestions on how to make it have more power?????
Anyone can e-mail me at REULER@gmail.com
Thanks
reuler
There are lots of things you can do, but first things first... what kind of
budget are you looking at. Just adding headers and exhaust will not do much
for a stock engine...
take a good look at the money you plan to spend and if you spend it
effeicently on the right combo of parts you can improve what you have. If
you spend it on the worng parts, you could just end up making things worse.
corbett_auto
Well, to be honest, it doesnt really matter the cost, but i would like to
keep the same enigine in there if possible.
reuler
Depends on how much horsepower you want to make. I'm not to savvy on this
particular engine (or most engines for that matter) but you may want to
look into getting a cam with a larger lope and/or boring out the cylinders.
These will net you some pretty big gains, so you'll have to at least do
some research to figure out if the other stock parts in the engine can take
it. These are also a good bit of work, probably best left to a pro if
you're a rookie.
For smaller gains things like headers, higher flowing carb (1978...guessing
it's still carburated), and gears will help. Also, if it's an automatic a
torque converter with a higher stall will keep you in your powerband more.
Keep in mind that many of these things are going to KILL your MPG.
giant016
Well, the carburetor is a 4bbl that needs to be replaced, so i might be
losing power through there. I would like to get maybe a 750cfm carb, but
would that add any horsepower? Well, when i bought the car i didnt buy it
for the gas mileage. And one more thing, i was told that when i bought the
car it was bored out from a 400 to a 455, is that even possible?
reuler
You are looking at this the wrong way. You can not just simply bolt on a
few items and boost horsepower... This is why I asked the budget. Also as
you increase power you also need to "beef-up" the weak links to keep them
from breaking....
Everything in (and on) the engine needs to work together as a team. Just
adding a 750CFM carb is not going to help if the engine is incapable of
handling the flow. Because of the year you are probably running low
compression/smog components. The first step would be to pull the engine,
disassemble it, bring it to a machine shop and have them insure it is solid
and strong enough to handle the HP number you are shooting for. Then either
swap out the heads or rework them to flow better, get a cam that will give
you power in the range you are looking for, match up a intake for the rpm
range, followed by a matching carb and so on......
With your current engine you have the potential to easily make 300 - 400 HP
(or more). But you might as well plan on a rebuild and spending $3500 -
$6000 in machine work, parts and labor. I am by no means an engine guru and
can not tell you which parts you need or giving specific advise....
Does this help any? It is hard to give you any specific advise until we
have an idea of what you are looking for or how much you want to invest
into it.
The potential is there, it just needs to be extracted.:2cents: :2cents:
corbett_auto
Yea, that helps, the problem is that im not sure what has been done to the
car, or what is already in the car. The technical name for my car is "fire
am" which i have looked online for it and have only found one website about
it. Im not sure if it is the same as the firebird trans am or if it is
different.
reuler
have you tried a hotbox. It will allow you up to 15° advance or retard
your spark and you know the rest, the better air to fuel ratio can mean the
world
mrblaackk
they made a world of difference, but I have 403 Olds try them USD50 is set.
But it's worth it to vacuum leaks, starve power also
mrblaackk
This might make me sound stupid, but is a hotbox?
reuler
I also have another question, i want to repaint the vavle covers. Will i
need to replace the gaskets after i take them off?
reuler
Even if they don't fall apart I'd replace the gaskets while you have access
to them..they're not too expensive and the car is 30 years old.
Don't feel bad, I don't know whata hotbox is either...or at least not in
reference to a car.:smoke:
giant016
