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It's been done and rather nicely. I don't remember the the member's name but maybe someone who does will chime in.
But it sticks out of the hood, ruins the look of the car, and ruins the weight balance.

You could try to hide a hot rod aluminum Montreal V8 under the hood like this project...
http://www.alfabb.com/bb/forums/spider-105-115-series-1966-1994/74007-spider-improvement-effort.html

You could hide a hot rod South African 3.7 Busso V6 under the hood like this project...
http://www.alfabb.com/bb/forums/engine-conversions/31782-one-demon-possessed-91-s4.html
 

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But it sticks out of the hood, ruins the look of the car, and ruins the weight balance.

You could try to hide a hot rod aluminum Montreal V8 under the hood like this project...
http://www.alfabb.com/bb/forums/spider-105-115-series-1966-1994/74007-spider-improvement-effort.html

You could hide a hot rod South African 3.7 Busso V6 under the hood like this project...
http://www.alfabb.com/bb/forums/engine-conversions/31782-one-demon-possessed-91-s4.html
Chevy LS would fit under the hood and isn’t much heavier. Not that I am advocating such a thing. Bigger problem is the rear end. To go beefier you have to add a lot of weight unless you are doing a full IRS conversion. All the stronger rear ends from old American cars are super heavy. At that point you are just building a new car under a spider shell.
 

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Discussion Starter #45
Nealric, I've learned the hard way in the past about exceeding a vehicle's design limits. One... don't turn up the boost on a Maserati Biturbo. It equals a blown head gasket and burned/cracked valves. As you said, beefing up an engine too much will force you to replace other components, which can become among other things, economically unwise. Last night looking at how supercharger kits were engineered/installed on other vehicles I sure was envious of the cast metal parts they were just able to bolt on and motor away with. It made a $4000 kit seem like a real bargain!
 

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Discussion Starter #50 (Edited)
u gotta b crazy! Leave the poor car alone. Or buy a Cobra!
This is the only reply I will make to people who are somehow offended by what I have the right to do to my own car.

"Leave the poor car alone." The poor car who gets to kick its rubber up & rest in my temperature controlled garage? The poor car who may never get rained on for as long as I own it? The poor car who has an owner fully capable of fixing almost any problem? The poor car which has already had all the scratches and parking "whoops!" polished out of its pretty facade? The poor car who its previous owners couldn't be bothered to fix mechanical problems until the car refused to run? That poor car has been rescued. That poor car has never known it so good. That poor car won the lottery with me.

To those who just can't picture a blown Alfa I say this:
1) What about the 75 Turbo? Is it less of an Alfa than the normally aspirated version? Go look at the prices people ask for the turbo verses the NA version. That will tell you the answer.
2) Fiat Spider Turbo
3) Fiat Spider Volumex
4) Which are the most valuable Fiat Spiders? The two above.

Cars are malleable. Look at all the versions of the 911 Porsche has been able to turn out over the decades. Heck, look at the Alfa 105 itself. Alfa could very easily have developed it further. They were very conservative. I don't think anyone would argue that. If they'd continued to produce it it would almost assuredly have been upgraded to the TS, a more powerful engine. When I am done you will not know from the outside that the car has been touched. However if I wanted to paint it pink and call it Polly, that is what the concept of personal property is all about.
 

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Interesting thread. I have been thinking about a turbo setup in my '83 because it's 9:1, I have it (it's just sitting there, and it's not too nice), and well, I love turbos. They're nifty. Programming your own fuel maps is nifty as well, although I might try to get the L-tronic to work. There is a lot of room in the bay for goodies.

I have been working toward getting a welding setup so I can make the exhaust manifold. I didn't realize there were manifolds out there. Are these hard to find?
 

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You All Underestimate the Capabilities of the Alfa Engine

Only those who’ve driven a turbo spider can understand >:)

By the way, a Cobra was an AC ace with a motor swap. Not really too different from a Spider.
Here are rear wheel power and torque curves from a 2 liter Nord with over 60K miles on the build. The dual traces show the effects of intake cam timing. This is a high end build.

On the other end of the scale was the Grassroots Motorsports Challenge car. Stock (cast) pistons were machined to reduce the compression ratio ... otherwise all internal parts were stock. We even reused the original bearing shells to save money. The whole car was built for less than $2000 (not including our labor). With the help of some race gas, we ran that engine at 18 psi boost and 8000 RPM. It was never dyno'd and the engine was removed soon after the event, but the bearings still looked good and the major parts went into a high end NA race engine.

Head gaskets are not a problem IF the liners are level and o-ringed and have the correct projection. And 70 lb-ft of torque on the head nuts is not recommended or needed. All that does is distort the valve seats.

The differential will be the weak link. My pinion bearings have been replaced a couple times. I'll be adding a cooler for the track. For street use, the cooler is not needed

2_liter_turbo_HP.jpg

2_liter_turbo_Torque.jpg
 

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Discussion Starter #53
Interesting thread. I have been thinking about a turbo setup in my '83 because it's 9:1, I have it (it's just sitting there, and it's not too nice), and well, I love turbos. They're nifty. Programming your own fuel maps is nifty as well, although I might try to get the L-tronic to work. There is a lot of room in the bay for goodies.

I have been working toward getting a welding setup so I can make the exhaust manifold. I didn't realize there were manifolds out there. Are these hard to find?
This is a picture of the exhaust manifold from an Alfa Romeo 75 Turbo EVOLUTION, Alfa part number 60535032. Everything I've read leads me to believe they'll bolt to a Spider engine, but please don't take my word for it. The outlet is a T3 flange, so any turbocharger with a T3 inlet on the turbine side will bolt to this exhaust manifold... and that's a lot of turbos! The 75 Turbo was never sold in the USA, so you'll have to source one from overseas. If you find where to get them let me know.
 

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Discussion Starter #54

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Head gaskets are not a problem IF the liners are level and o-ringed and have the correct projection. And 70 lb-ft of torque on the head nuts is not recommended or needed. All that does is distort the valve seats.
Nice to see you posting! The 70ft-lb hot torque is Richard Jemison's recommendation for race motors. Curious what you've used for your motors. 65?
 

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Nice to see you posting! The 70ft-lb hot torque is Richard Jemison's recommendation for race motors. Curious what you've used for your motors. 65?
With the Reinz gaskets I use 55 lb-ft on NA engines using Dow Molykote. On the turbos I'll go up to 60.

It's extremely important that the tops of all the liners are even. The gasket will be more likely to fail at a low cylinder. But the most common cause is a bad tuneup ... the pressure spike from detonation can be twice as high as normal combustion.
 

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Having been down this decision-making road before, I'll add my $0.02 (be careful, you get what you pay for..).

If you have the capability, tuning know-how, and know someone who can make a custom exhaust manifold, a turbo setup seems to be the most straightforward way to more power.

Supercharger would be better from a driveability point of view, considering the automatic, and cheaper to implement, but personally I hate the racket those things make. The Spider does not have a ton of sound-proofing, so it's not like a Mercedes where you can barely hear the engine. A small turbo would be better than a large in this case, so that it spools up quickly. If you're not looking for mega-power (250hp +), a G25 should suffice, and wind up pretty quick.

A 200-225hp Spider should be well within reach with a small turbo, new manifold, 8.5 or 8.0 pistons on a fresh rebuild, and programmable EFI.

Sure, you can get similar from a well-built NA engine, but the low end torque will never be the same as in a boosted car.

Having said all that, here is another option:

You already have 10:1 pistons in this thing. A nice set of cams made for low end power (RJR can likely help you here), along with programmable EFI and a better flowing exhaust may make enough power to put a smile on your face. 150-160hp (with a nice broad torque curve) is certainly in reach, and this is a heck of a lot cheaper option. If it's not enough, you already have purchased, wired and programmed the EFI, so 'upgrading' to a turbo setup could be a next step and you wouldn't have to toss any of the new parts you just bought.

This is where I landed with my Alfetta. No reason to re-invent the wheel here: these cars are great stock, and you really don't need a ton of extra power to enjoy them. It's a classic Alfa, after all. If I want to blow the doors off everything else, I'll just hop in the Giulia Q :)
 

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Bulgaria is to Western Europe as Mexico is to North America. A lot of tooling and manufacturing ends up there because of the low labor rate. But yeah, also sometimes sketch I suppose. Poverty is as poverty does. That manifold looks awesome, though.

Part of the journey for me would be buying a tig welder and welding up a titanium exhaust manifold. For no good reason except I want to do it. Well, because I can afford a box of titanium parts and it seems to be the most forgiving material as far as warping goes. If I had the welder already I would try it, but I don't have it yet, and I doubt I'll buy it in the next couple of years. But when I do I'll come back and post pics of my horrible manifold!

I'll keep an eye out for a 75 turbo manifold, but now that you've shown me a shiny stainless manifold I'm kind of convinced that's what I want to make!
 

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Regarding head gaskets I run 7-8 PSI boost (older Eaton m-65) with a Rienz gasket on a stock compression 86 2.0L with no problems in 2500 miles. I used an air to air inter-cooler from a 75 turbo because I had it and later added alcohol injection to address pinging. if I were doing it again i would skip the inter-cooler and go with the alcohol only.

Greg Gordon's book is quite helpful and practical. I haven't dynoed it but guess its around 180-200 hp which is a blast to drive. Lots more low end torque. the rest of the car is stock and handles the power well.

Good luck,

TD
 

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