1980 FI - Best Bang for the buck on performance?

[JFreeman]

I would agree that IF you're using a stock Bosch FI system, then you're going to eventually run into some limitations with what you can do. Several years ago I literally spent months reworking my 1980 FI Spider - engine, tranny, suspension, brakes... the works. Overall I was pleased with everything except the engine and that element proved to be a disaster of sorts. Without a doubt, my downfall was the 8 mm domed pistons. Those puppies create some serious compression and the stock Bosch system just isn't set up to get enough fuel into a high compression motor to keep it from sounding like a ping ball machine. Bosch engineered the L-Jet to be economical and reliable, performance wasn't its strong suit. About a year later, I built up a second motor using 4 mm pistons, but other interests cropped up and it's still sitting on the engine stand awaiting the transplant. Oddly enough I actually had 4 mm and 8 mm pistons in hand at the time of first rebuild and in hindsight could shoot myself for not going with the 4 mm ones. But... the new motor will get a set of Marks cams when it goes in (hopefully later this spring) and those weren't available when I did the first rebuild.

Oddly enough since moving up to Franklin NC, (2500-4000 ft) the motor does much better than it when I lived in Athens GA. It pings much less readily especially if you can keep the revs above 2500. I'm assuming this has something to do with the lower ambient air pressure and the subsequent drop in compression.

[burgandy81]

Hi CLudwig,

I have a Megsquirt on my 81. It was done primarily to prepare for a turbo. My set up is MS II, custom fuel rail, large injectors, EDIS ignition with COP, Lancia Thema intake manifold with Alfa TB, custom wiring harness for all EFI and ignition. I did almost all of this at one time and have had a difficult time tuning. With a large number of changes (ignition, injectors, wiring etc) it is difficult to isolate issues.

My impression at this time is that MS is fairly good if you ease into it a little slower than I did. The new TunerStudio software is very good and should be reasonable to set up on a stock Spider.

My advice (if you go the MS route) would be to start by converting to fuel only with as close to stock system as possible. This will allow for MS tuning with the least number of variables. Once you have a running car again you are in a very good place to upgrade injectors, ignition, sensors, cams or almost anything you can imagine.

The best (most relevant to Spider) MS threads I have found are on Lancisti.net. The Scorpion section has its own sub-section for EFI conversions and several very well detailed threads are available.

I am a huge fan of Millers Mule parts if you go down the MS path. They make an excellent crank pulley with toothed wheel and sensor that is required to supply MS with and RPM signal.

At one time there was a few Suirted Spiders around but I have not seen much in the way of posts lately.

Best of luck,

Jordan

[vandor]

...Without a doubt, my downfall was the 8 mm domed pistons. Those puppies create some serious compression and the stock Bosch system just isn't set up to get enough fuel into a high compression motor to keep it from sounding like a ping ball machine.

Sorry, but high compression does not need more fuel. More fuel is needed if more air enters the engine.
The 8mm dome pistons create too high a compression for any amount of (pump gas type) fuel. For example, if one would run high octane racing fuel (100 octane, or somesuch) then there would be no problem with the Bosch FI and the 8mm dome piston combo.

[BEEK]

Csaba, the age of the cams has nothing to do with it. You had 9.8 compression, far more than stock. You of all people should be aware that higher compression is one of several items that make a 40/80 cam acceptable for the street

dynamic compression vs static compression, volumetric efficency, all play a great part in this equasion. remember you are trying to improve on a pretty good wheel, best not try and reinvent it, but massage it.

i have built 200+fwhp 2.0l fiats i have driven them on the street too. had to keep using race fuel or back down on ignition timing , and change cam timing to make them streetable on pump gas, but was easily done.

[CLudwig]

Thanks again for the great info!

Is it true that if I exceed 130HP or so that my Trans and rear end are going to need replacement too?
From what I've read, they are not designed to handle much more power than they had stock in the euro version.

[So Cal Mark]

it would mostly depend on how much you abuse the drivetrain. It's not hard to break the rear end with a stock motor if you try

[CLudwig]

it would mostly depend on how much you abuse the drivetrain. It's not hard to break the rear end with a stock motor if you try

I do try, my current motor must be very weak ; )

[vandor]

Is it true that if I exceed 130HP or so that my Trans and rear end are going to need replacement too?

It's more like 150 HP, and yes, greatly depends on how you drive. The Euro supercharged versions (Volumex) had 135 HP and a lot of torque.

[dantye]

It's worth noting that these cars have their limits. I mean, I won't get very far tweaking my old Buell motorcycles to try and make them perform like a new Yamaha Superbike racer. It's the same with your wonderful car from the early 1980's. Another way to put it is to enjoy the car for what it can do, and don't lament what it cannot perform. ...

Since I seem to be getting in over my head anyways.. I'm take your advice; thanks for that. Very well said by the way; you're 100% correct. I would still like to add more power, low end torque especially, but doing everything you mentioned above is probably my best bet on my limited budget and limited skill level.

It may also be worth noting that, in order to enjoy the results of your effort, make sure you are using the correct transmission, differential, and engine oil. You can learn a lot about that just by searching this board (not that everyone agrees!) But such cautions can save your car. For engine oils, with over 80K on mine, I have found Shell ROTELLA 15w40 to work well and it is not that expensive, but you will find MANY other suggestions here.
Even more important, KNOW how many miles are on your timing belt, and have it replaced if you can't confirm that it has under 35K miles on it. If it goes, there is a good chance you won't have an engine.

[babu2001]

I'm too also looking for the best performance for about 2500$ for my '83. The headers and exhaust line is my first though. (2 or 2 1/4 should I use?) Yes, porting the head, new valves and cams sound great (I'll do it in time) but does anybody have install a "universal" turbo kit like this one http://www.ebay.com/itm/Custom-Race-T3T ... es&vxp=mtr ? I've never got a turbo but allways wanted to try it. Isn't it a good bang for the bucks? Will it means changing the injectors, fuel pump, timing gear, etc? I just want to get to the 130 HP mark and still be using normal gas, not jet fuel...

[vandor]

There are a couple people who have put turbos on their Spider, their experience would be invaluable when making a custom system. One of them, James S., hangs out on the mirafiori.com Forum.

[So Cal Mark]

I doubt you can do a custom turbo install for $2500 and the 130hp target isn't too difficult for a normally aspirated motor

[narfire]

Dang... wish I had got my car to the dyno before the snow flew.I 'm going to "Guess" I might be around the 125 hp mark (hope) I love the power now it has been dialed in correctly and still have the original FI system.I'm just guessing with the knowledge the car was around 105hp stock. Another month or so before the gravel is off the roads.
Chris

[Turbofiat124]

Thanks again for the great info!

Is it true that if I exceed 130HP or so that my Trans and rear end are going to need replacement too?
From what I've read, they are not designed to handle much more power than they had stock in the euro version.

My turbocharged Spider dynoed 123hp at the wheels and I have broken nothing yet.

[Turbofiat124]

I doubt you can do a custom turbo install for $2500 and the 130hp target isn't too difficult for a normally aspirated motor

Here I am.

I have built three systems. Two for my Spider and one for my Yugo.

They are not that expensive to put together yourself. Kits are what costs you because your paying for someone else's R&R and a new turbo.

I would not buy a new turbo. There are lots of good used T25s and T3 out there. I would not pay more than $300 for a used turbo. I paid $50 for a T3 from a Volvo 240 and another $50 for a rebuilt kit.

The silicone hoses are excessively expensive though. I don't know why.

Use brass hose fittings and neoprene hose for the oil return instead of that Earl's braided crap with aluminum fittings that like to strip out.

If you did all the work yourself you could get by with around $500 to $700. Allot less than a reworked engine.

There have been a couple of people trying to recreate the PBS turbo manifold which I have on my Spider but nothing seems to have developed as of yet.

I've been wanting to build a system for my 131. I have most of the parts already, just not any time to do it! I have a plan to build a turbo exhaust manifold out of well pipe which I have used to make sections of downpipes out of. It's thick and heavy and won't burn out.