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Discussion Starter · #1 ·
Will someone please list the options (and relative costs) for all known performance upgrades on 1750 & 2000 GTV engines? Pros and cons would be helpful too. This newbie greatly appreciates your help!

Thanks!!!
 

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Go to the engine rebuilding forum and find "Rolling Road Results! 2 Litre NORD" for starters.

The bb has a wealth of information concerning engine mods which car be easily found using the site's search engine.
 

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For either one, a fully ported and polished head will do wonders. An efficient exhaust system will also help. Carbs and cams round out the list. The head is by far the most important part of building a hot engine. The down side is that its expensive. You also need the compression to work with the big cams, however a lesser cam on a fully prepped head will go a long way. You might also find your mileage is better, the car is more fun to drive and unless you go crazy with the cams, there really isn't a downside aside from a lighter wallet. You can bump the compression up with the 2L, but that doesn't give you much aside from the need to run premium gas with a detuned engine (so it won't ping.) Clean up the head, and keep the stock compression (or bump a little if its on the low side stock, less than 9.5:1. Above about 10:1 you can start running into issues.) Lighten the valves, flywheel and con-rods, make sure everything is balanced as well. The light flywheel will give you a really crisp throttle response, lighter valves allow more rpm (to a degree) as the springs don't have to work as hard.

There isn't a lot of power to be made out of these engines. The design of the head isn't very good, it doesn't flow well. A fully race prepped 2l engine only makes about 200 hp at really high rpm and the power band is very narrow. Not much good for a street driven engine. I think about the most you can make with a street engine is around 150 hp at the wheels. That will be a pretty high strung engine as well. If done right, it should be reliable for a long time however.

just my $.02,
Will
 

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Richard Jemison
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Experts?

There isn't a lot of power to be made out of these engines. The design of the head isn't very good, it doesn't flow well. A fully race prepped 2l engine only makes about 200 hp at really high rpm and the power band is very narrow. Not much good for a street driven engine. I think about the most you can make with a street engine is around 150 hp at the wheels. That will be a pretty high strung engine as well. If done right, it should be reliable for a long time however.
Will, Why don`t you share with us how many of these motors you`ve built?:rolleyes:
 

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Discussion Starter · #5 ·
Richard,

Maybe you have something valuable to add to this post?
 

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Richard,

I haven't built any. That said, I am interested in doing so, and from what I have read on the subject, this is what I have found. I know for a fact that you know far more than I do on the subject, and would like to hear what you have to say. I know that you are not a big fan of the book by Jim K, however there isn't much else printed that I can find on the subject. I have built an engine, I have hammered on it for the past 50K miles, and it runs like an Omega watch. No its not an american v8 or honda. It is a 40 year old 8 valve SOHC 2L that no one makes parts for, and it puts down 150+ hp at the wheels. I know what that head flows, and from what I have found with published dyno pulls on full race engines, they seem to be limited to a little over 200hp at what looks to be a rather high rpm. I'm trying not to compare apples to oranges here, but I would expect the 2 to make about the same power based on displacement, but they don't. At least not in a street driven form. I know many other factors come into play, but I can't see a Nord 1750 or 2L being very streetable making big hp. If it can be done, I'll take notes, and gather the parts to do so. I'm not trying to spread bad info here.

I guess the real answer to the original post is how big is your bank account? Cubic $$ = hp.

Will
 

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It is lots of fun to have 200 hp on this engine and it is lots of hp for a non-turbo engine.

I know I enjoy mine:

 

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Hi fangio,

I think you could buy about 3 books, then spend a few hours with a race mechanic and still not have all the answers to your seemingly simple question. You are asking to know everything about everything.:)

Maybe if you gave more information since a full win-at-all-costs race application will be different to a fun daily driver which will be different to a long distance tourer. Even then it would be hard to answer the question besides saying give it to the best mechanic you can with lots of cash because they won't give away all their secrets.

For the absolute best performance everything has to be integrated to work as a whole. You can't buy bits and pieces and stick them together and hope they work (unless you want to end up spending twice as much as giving it to someone who has already done that).
 

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Discussion Starter · #10 ·
AndrewO,

Good point. I appreciate the light you've shed on my post. When I originally wrote it I should have specified that I was asking from the position of either "fun daily driver" or "long distance tourer". I'd be interested in how those two set-ups vary (other than gearing), what's involved and associated expenses. Full race was never my intent.

Fangio
 

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AndrewO,

Good point. I appreciate the light you've shed on my post. When I originally wrote it I should have specified that I was asking from the position of either "fun daily driver" or "long distance tourer". I'd be interested in how those two set-ups vary (other than gearing), what's involved and associated expenses. Full race was never my intent.

Fangio
Fangio,

I kinda figured you were after a street engine. If it were me, I'd be looking for as much hp as I could get, and still have it live for a long time. That said, I'd go for lightweight internals, a really well done head and a set of good cams. I'd also stay away from really high compression (easier to find gas, and its easier on the internals as well.) I'd say 10.5:1 compression is as high as I'd want to go. Modern thinking, and materials can make things work better than they were ever thought to perform. The biggest bang for your buck would be found in doing the head, and a lightweight flywheel.

just my $.02

Will
 

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It is lots of fun to have 200 hp on this engine and it is lots of hp for a non-turbo engine.

I know I enjoy mine:

YouTube - Alfa Romeo Giulia Super Beautiful and Fast
Reuven,

What did you do to build that? Is it a 2L or 1750? That thing gets on it. If I had to guess you drive it all over the place and its great. I did notice the idle is pretty high however.

It seems very streetable, lets hear the secret.

Will
 

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Fangio,

For me and my tastes a fun daily driver is quick revving (light internals and flywheel) and power up high so you can feel (and hear) the change as it comes on song, but not too high to make it idle badly or wear out and be unreliable. A long distance tourer is set up for low down torque and smoothness so you can be in any gear at any revs and still keep going strong. I guess they are subtle differences in tuning and components but what I meant when I said it all has to match with the same goal in mind.

I'd agree with blpltGTV but add that to make it effective you need to get the air in and air out. Depending on the tune that means new internals for the 40DCOE's (most likely for non-race) or a move up to 45's (or whatever you do to injection over in the US), and an exhaust system that can get rid of all the gases. I'm not really qualified to go into all individual prices or pro's and con's of each mod.

Expense.... The only correct answer is "More than your think."

I'm heading down the path of an engine rebuild and have a budget (always changing) of about $16,000 in mind for new carbs, head work, high compression pistons and liners, new rods and bearings, balanced crank and everything else that can be balanced, aluminium flywheel, race cluth, water and oil pump while there. I already have the headers and totally new exhaust so that isn't included. The extras like ingnition, oil cooler, thermatic fans are on top of that. I can't afford the gearbox so I'm gentle. That is probably considered doing it cheaply but should see me mid-field on the track (if I was good enough) but with the right components should see a good street engine. If I wanted to be at the front then maybe double the number.

Bear in mind this is what I want to do, not what I've already done so I'm happy to hear others points of view.
 

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Reuven: Your car is awesome. It's obviously very fast and does a great job of showing how a well built Alfa twin cam can run.

fangio8c: Your question is just too broad in scope for anyone to answer in an automotive forum. I suggest you buy and read Jim Kartalamakis' book, as well as the Braden Bible. These two will give you a good idea of what's realistically involved for various upgrades.

I have only recently started playing with the 4cyl Alfa engine. Most of my experience is with the V6. However I am impressed with the 4cyl and I think it's highly under rated. My 4cyl power results should be ready in a couple months. Hopefully they will be impressive.

Greg Gordon,
hiperformancestore.com
 

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Reuven,

What did you do to build that? Is it a 2L or 1750? That thing gets on it. If I had to guess you drive it all over the place and its great. I did notice the idle is pretty high however.

It seems very streetable, lets hear the secret.

Will
Well it's not a big secret, just the usual things:
- High comp pistons
- High lift cams
- 45 Dellorto's
- Light weight flywheel
- GTA Exhaust
- All inside engine parts were lightened, polished, ported (this is the biggest secret), this was done by an expert in these engines
- 123 ignition

The idle is high due to the high lift cams.

Hope this answers.
Reuven
 

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Well it's not a big secret, just the usual things:
- High comp pistons
- High lift cams
- 45 Dellorto's
- Light weight flywheel
- GTA Exhaust
- All inside engine parts were lightened, polished, ported (this is the biggest secret), this was done by an expert in these engines
- 123 ignition

The idle is high due to the high lift cams.

Hope this answers.
Reuven
Reuven,
While you did answer the question, it was a little vague. How high is high compression, how large are the cams? Is it a 2L or 1750? I'm really curious as to how that engine is streetable based on the info I have gathered both from Jim Ks book and Pat Bradens books. I'm guessing your compression ratio is greater than 10.5:1. Here in the US, California in particular, I'd be going to the race track and paying $8 per gallon for race gas. Our 91 pump gas just doesn't cut it for old non computer controled high compression engines. I have to detune the heck out of my track car to get it to be happy on standard 91 pump gas, and that is only about 10.25:1 compression.

Will
 

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Reuven,
While you did answer the question, it was a little vague. How high is high compression, how large are the cams? Is it a 2L or 1750? I'm really curious as to how that engine is streetable based on the info I have gathered both from Jim Ks book and Pat Bradens books. I'm guessing your compression ratio is greater than 10.5:1. Here in the US, California in particular, I'd be going to the race track and paying $8 per gallon for race gas. Our 91 pump gas just doesn't cut it for old non computer controled high compression engines. I have to detune the heck out of my track car to get it to be happy on standard 91 pump gas, and that is only about 10.25:1 compression.

Will
It's a 2000 engine with 11.5:1 CPS pistons, the head is a bit lowered so I believe the comp ratio is 12:1. In Israel you can have 99 octane on the fuel pump, this is what I am using with a retard ignition.
$8 per galon is unfortunately our normal pump gas price ($9 to be more accurate). Cams are 11 mm high and about 300 deg duration.
 

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The price of gas doesn't bug me as much as the fact that there are only 3 race tracks in a 180 mile radius, one 150 miles south, one about 150 miles north, and one in my back yard. Finding anything but 91 anywhere in between is less than likely. Makes going any place farther than that a mute point unless you bring a gas can with you.:rolleyes:

Your numbers are completely believable with the compression ratio and cams. :D Its just not really possible to do here in the states with our lousy gas. Did you have your head flowbenched when it was built? I'd be interested in finding out what a well built Nord head will flow. In Jim Ks book it looks like its 120-130 cfm for a full race head. To compare apples to pears, the head on my Datsun 2000 (U20 engine) flows 212.4 on the intake and 172 on the exhaust. Granted its a wedge shaped combustion chamber, but its not a cross flow. It still only has 8 valves, and one cam. If I could build a Nord engine with the same hp that runs on 91, with the reliability that my U20 has, my Alfa would be my car of choice. I have 50K miles on the U20 since I built it back in 2004, and its never missed a beat. It gets raced at least once a month, sometimes more.

If I can get that out of my Alfa, I will be a happy camper.

Will
 

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fangio8c,

I'm surprised someone hasn't already supplied this information. Go to "msiert's black Spider" thread. Murray Siert has a S4 Spider with 167 HP at the rear wheels on U.S. pump gas. I have driven the car, and it is completely streetable with no bad habits. This is a full-out EFI engine, with SVT on both cams, and was developed with profesional assistance. He documented the entire process, as well as the cost (around $24,000 for all modifications including chassis, roll bar, race seats, etc)

Will someone please list the options (and relative costs) for all known performance upgrades on 1750 & 2000 GTV engines? Pros and cons would be helpful too. This newbie greatly appreciates your help!

Thanks!!!
 
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