Installing Bosch fuel Injection for 1979 Fiat Spider

[aslives]

I've got a 1979/ 2000 and am looking for a bit more umph. Live in California so messing with webbers, etc... is not an option.

My mechanic was talking to me about installing a Bosch Fuel injection taken from a spider from the early 80's. Cost aside, and assuming he knows what he's doing, is there any major downside to this? Has anyone tried it?

I imagine the performance gain would be substantial. Love to hear from the pros.

thanks!

[BEEK]

i have injected carb'd spiders may times. it is truly a bolt on operation, very easy. just buy all the parts and go for it. the fuel tank is one thing most people dont think about. but i have used a carb tank and it will pull from the stock sending unit and work fine. long term, it may cause fuel pump issues. but have never had any to this point

[aslives]

Thanks for the rapid and positive reply! Can you speak to performance - is it a lot better? Would you expect any risk to reliability with this sort of modification?

[aslives]

Thanks for the rapid and positive reply! Can you speak to performance - is it a lot better? Would you expect any risk to reliability with this sort of modification?

[rebar1111]

According to the book, FI is like 20hp over stock carb. I have a near complete used FI package I could offer if you choose that route. PM me if interested.

[toyfiats]

Can you speak to performance - is it a lot better? Would you expect any risk to reliability with this sort of modification?

If you have a chance to drive an FI Spider, try and do so. Like was mentioned, it's about 15-20 hp difference, which may or may not sound like a lot, but it's hard to describe how different a stock '79 (or any carbed 124) compares to the later FI. FI is much smoother, but perhaps not as aurally pleasing. As to reliability, Bosch injection is pretty simple and usually VERY reliable. However, you are now at the mercy of more electric switches and a computer, but isn't something I would be too concerned about (having exclusively driven FI Spiders for 20+ years now).

I've never done the conversion, but have seen several, and it is relatively straightforward. However, depending on how creative and concerned for visual appearances you are, to my mind the biggest hurdle is determining how to support the AFM and airbox, since the stock mounts don't exist on your '79 (at least I'm pretty sure they don't - been years since I've seen a '79). Search on posts from member Fiatfreak for an example of a VERY clean conversion.

[Tobi]

We did several conversions on Opels, back in the 80th and 90th and that was very much the same thing, same Bosch fuel injection. In our case it was about a day or two of work and much more power for only pennys.

[MrJD]

the fuel tank is one thing most people dont think about. but i have used a carb tank and it will pull from the stock sending unit and work fine. long term, it may cause fuel pump issues. but have never had any to this point

Beek, could you not just install all the engine bay FI equipment, and run an in-line aftermarket fuel pump... leaving everything else stock? If you have a pressure regulator, it should work fine?

[wizard124]

i have injected carb'd spiders may times. it is truly a bolt on operation, very easy. just buy all the parts and go for it. the fuel tank is one thing most people dont think about. but i have used a carb tank and it will pull from the stock sending unit and work fine. long term, it may cause fuel pump issues. but have never had any to this point

Good questions to ask the mechanic, "Does he have everything needed and or what also needs to be bought? Does everything he have work properly? From a runnign car, or from a salvage and condition unknown?"

Assuming he has an operational FI system with AFM, air box, snorkel, intake manifold, injectors, ECU and wiring harness, etc.

You need a different coolant T to house the temp sensor. A different exhaust manifold for the O2 sensor. Its a 4-2-1 exhaust which may be different than what you have now. An electric fuel pump and filter with mounting brackets. Ask him about coil and electronic ignition (I think you have the same now although there will be new FI leads). There is an under dash mount for the ECU. Different throttle cable.

How is he going to run the harness? There is a thick bundled cable that runs from passenger to driver side along the firewall. I think it would be difficult to install with the head installed. I added a sheath, that you see in the photo. It may be hard to route this behind the cam boxes.


This pic shows the air box and AFM to give you an idea.


I am not trying to talk you out of the conversion, just playing Devil's advocate. Many details to cover and if you had to buy or replace faulty components, the cost add up quickly.

[divace73]

I'd say go for it, compared to what things cost here in Australia doing things in the US is much more economical.

Get everything from the donor car, including harness, dual relay, petrol tank, electric fuel pump, if your battery is already in the back (which I think it is) then that will also help with the placement of the AFM. See if you can get the AFM support/mounting bracket from the donor car as well and weld it in your car.

You will need to supply a thick cable for power from the battery to the relay if there isn't anything available.

Just be sure to put all new rubber bits in (Hoses on the injectors etc) and maybe get the injectors testes and cleaned.

You would want to make sure it all works well to start of with.

[vandor]

Yes, definitely a good performance improvement over th stock 2000 carb, and it's a lot smoother too.
On my personal page below the is a section that has some info on the conversion.

[Holshot]

I guess I'll throw my .02 in as well... I have both a '79 and an '82 And the diffference is noticeable. With that said, a well tuned upgraded carb on the '79 would also make a world of difference. I've had some seat time between the two recently and after driving the '82 and getting in the '79 it is night and day. Now my '79 is bone stock with all emissions bs and restrictive carb so opening it up would be quite an improvement over stock and make it as enjoyable as the '82 I bet.

Depending on how much power your trying to make I think it would be a toss up. I'm in the same boat you are in to a degree, I originally bought the '79 for my dad but he hasn't taken to it and while I LOVE the car being an all original 35k mile car I'm disappointed in the performance and if I keep it I would need to upgrade it but I'm torn to pop its cherry, lol. They are only original like this once. There's no point keeping both so I have to make a decision, keep the '79 and mod the heck out of it to make it more enjoyable or sell it and focus on the '82 which in its current state is more enjoyable.

The other dilemma is then choosing what you are more comfortable with in terms of wrenching on a car. Are you a guy who likes to turn your own wrenches or can diagnose issues when they arise? With a carb setup it's definitely a lot more simple especially if you ditch the stock '79 carb setup and upgrade to the one of the large selection of Webers and EMPI carbs that Mark sells to make up for the shortfall in power and will clean up that rats nest on the intake side. The FI route is not to bad but if you're anything like me electronics drive me crazy and diagnosing a rough running issue or a no start can be challeging as many things are dependent on other things for it to running properly. If you have to pay someone to chase electrical gremlins that can get pricey.

Bottom line, carbs in my opinion, are simple and "easier" to keep up with in my opinion but you may leave a few ponies on the table but again that may not even be the case with the right mods and at this level it's negligible possibly. Depending on your budget I would think a carb swap would be less expensive but if your saying in CA you can't do it then I suppose there's only one option for you if you want the extra power. I don't see how they would even know though considering how old the car is as I don't think that they would be able to tell the difference with an upgraded carb. Looks like both of us have some decisions to make, lol... Let us know what you end up doing, Good Luck!