Increase Performance?

[airforce89]

I own a 1976 Fiat and am looking to increase the horse power, torque etc... I an also thinking about maybe turbo charging it. But I am unsure what to use. Any ideas or suggestions on what works best and what not to use?

[Mathew26]

To get some torque easily just put in higher compression pistons.
For the HP's you want you be looking at better carbs, hot cams, big valve/high flow head, & open exhaust.

As for Turbo - eh I don't go there.

Hope this helps.

Matt

[kmead]

So there are two basic approaches:

Build up a normally aspirated engine with hot cams, higher compression and either twin downdraft carbs or an aftermarket injection system like Megasquirt

Build up a strong motor with lower compression, a K04 turbo and either pressurized carbs (not suggested) or Megasquirt injection. Additionally I would also want to have an intercooler, an oil cooler and a larger and deeper radiator.

Either approach will be fairly expensive and they will create a very different character in the car.

One would also need to upgrade the brakes as well as they are really not up to the job of stopping a car that can go much faster.

[So Cal Mark]

first questions are how much is your budget and what are your expectations?

[airforce89]

Honestly I don't really have a budget being in the military I always have plenty of money so there isn't really a budget. As for my expectations I don't really know this is my first project car and I'm not sure what you mean by expectations.

[So Cal Mark]

wow, an unlimited budget
as for expectations, how do you expect the car to perform? How will it be used and driven? For instance, if it will be used for touring with the occassional high speed fling on a curvy road you will want to keep driveability good. If it will be a track-day car you may want a motor that is ragged to drive on the street but will have good performance for racing or autocross.
If you stay with a normally-aspirated motor, driveability will be sacrificed as you increase performance

[baltobernie]

There's also the question of where you live. Several US states require emissions inspection on 1976 cars.

There are a couple "rules of thumb" about increasing HP, the best one I remember is that the last 10 HP costs way more than the first 10. So if your smogged '76 isn't running very well, say 80 HP or so, getting it to 100 will really be noticeable and not too much money. Maybe just de-smogged with a performance carb, recurved dizzy, good exhaust ... under a grand (if the internals are in good order). Achieving 120 might cost several thousand dollars; 140 an arm and three legs.

As others have said, too much beyond 100 or so you're outrunning the OE brakes, suspension, etc. so the costs really begin spiralling.

[airforce89]

My expectations are i want it to be fast and powerful. The car will be a car that I will drive every day. What do you mean if I keep it normally aspirated it will affect driveability? And what do I do to fix it?

[baltobernie]

If you want a fast and powerful car, buy a used Z3 or a 2006+ Miata with 170 HP. Either would be a lot less expensive than trying to build a 1976 Spider with that level of performance.

[So Cal Mark]

without turbo or supercharging, your engine will have to be pretty radical to make anything more than 140hp or so. Radical enough that it wouldn't be enjoyable as a daily driver if you have the challenges of rush hour traffic or city driving.
We have several customers with cars in the 120-140 range that drive nearly every day and those cars are a blast to drive. They may not be as fast as a 911 or other high-priced sports cars, but they are fast enough to be lots of fun

[airforce89]

That sounds like what I want to do. What parts would you suggest I use to get my Fiat up in that range?

[fiatfactory]

.

[BEEK]

static compression vs dynamic compression. thats the big problem to solve, most people over cam thier engines for the street. stock cams will do much better that most performance cams on the street.

[So Cal Mark]

I agree about overcamming. Most of the cams I sell perform really well in the midrange and that's what I usually recommend unless you're building a race motor

[baltobernie]

It would be great if you could drive a modified Spider to determine if 120-140hp fills your need. I guess it really depends on your frame of reference. My 120-125hp 1973 is a lot of fun to drive, but the average minivan will blow it away from a standing start. A buddy of mine who drove my car for the first time said that he had a great time in the car, but his son's Solstice felt like a Corvette in comparison. The Spider was a very advanced car for its day, but the advances in technology since the seventies are staggering. I remember a Top Gear episode where the Stig in an econobox did a better lap time than a restored sports car of the Spider's era.