1978 T/a

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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

posted by  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.

posted by  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.

posted by  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.

posted by  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?

posted by  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:

posted by  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.

posted by  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

posted by  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

posted by  mrblaackk

This might make me sound stupid, but is a hotbox?

posted by  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?

posted by  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:

posted by  giant016

I have not heard of that exact product, but I assume he is talking about something similar to an MSD box. While it may help you some, it would be like anything else that you just bolt on....... Your engine will never live up to its full potential until you know that everything is working at maximum efficiency. Which means starting from the inside and working your way out. the other way (from the outside in) will only cause you more grief and money.

And yes always replace a gasket under anything you take off. You would save time and money, by just waiting and painting the whole engine after the rebuild. If the valve covers need painting it may be a safe bet to assume you need to rebuild the engine. In most cases an engine will be painted during the rebuild process.... if enough time has passed that the paint on the valve covers is bad..... I would assume a rebuild is needed.

posted by  corbett_auto

Has anyone heard of amsoil power foam? If so what do you think.

posted by  reuler

We use to be an Amsoil dealer years ago. At one time they were one of the few manufacturers of a full line of synthetic fluids..... good stuff in general, but sometimes pricey......

Power foam is it some form of cleaner or are you refering to their air filter (which is foam)...... If you are asking about a cleaner I personally think "Sea Foam" is great. You can use it everywhere: in the fuel tank, in the crank case, pour it down the throat of the carb, etc...... and it lives up to the claims on the bottle. As always be sure to read the directions.

posted by  corbett_auto

Does anyone know if a throttle body spacer add any horsepower, or would it be a waste of money?

posted by  reuler

Well, they'll make your walllet lighter, so I suppose you might gain some performance if you normally only carry change. If you can't pick up on what I'm saying; no, the TB spacers do nothing to help performance...they're snakeoil. Same goes for the "chips" sold on ebay, the tornado/vortex crap, and especially those gas magnetizer deals sold on late night infomercials.

posted by  giant016

Do you really want to add HP?

As a helpful tip your car does not have a throttle body. :banghead:

posted by  corbett_auto

Yes, i am looking to add HP. I am just looking for a fairly easy way to do it.

posted by  reuler

Honestly, there are very few cars that you can add a substantial amount of HP easily. And the few that I can think of are either turbo or supercharged, often those just call for upping the boost or swapping a pulley. A naturally aspiriated 1978 T/A can be built up, but if you want noticable gains there is no magic word. Cars from that era were choked by emissions junk as well as (somewhat) high gas prices. If you want to build this car, than build it, you have to stop looking at thinks like TB spacers for a quick fix...not gonna happen.

posted by  giant016

just face it, you are going to have to pull the engine. and have it gone through. therre is no such thing (as corbett said) bolt on power adders for that car. its old school, not a honda.

posted by  glagon1979

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