alfa 33 identification

[gti_rsi]

well thats a slight disappointment but never the less im still very happy with it!

[81Sprint]

Post 84 all the twin carb Australian 1.5 boxers Ive had have been the 105 hp engine.
Clayton105 is right they didn't produce the claimed 105hp, I think mostly because of pollution control measures.

As far as I can see what is causing this is
1: Slightly retarded timing.
2: The mess of re breathing/crank case ventilation piping that runs around everywhere pumping unburnt fuel and oil mist back into the carburettors.
3: Part of the antipollution system is a series of pipes running down into the exhaust headers if youve ever taken your headers off you'll notice that these pipes must cause significant exhaust flow problems.

My advice would be to find a set of earlier twin carb headers, or remove the pipes on yours and get the holes welded up.
Get a proper dyno tune.
Be "creative" with the rest of the anti pollution stuff, whilst keeping it legal looking.

[oz3litre]

Both my first 33, a 1988 1.5, and our current one, a 1988 1.7 carby model, crackle when lifting off. I always understood that it was normal for these cars. My Alfa mechanic has never said anything about it. I have also heard some people say they like it because it is a characteristic of the boxer engine with Webers. I would be interested to know if anyone has actually gotten rid of it and, indeed, whether there is any need to bother trying.

[gti_rsi]

its not so much the exhaust popping a crackling, i like that, but it does seem to me like it could be unburnt fuel being ignited in the exhaust, but i could be rong, unless unburnt fuel igniting sounds like a spark plug sparking up inside the engine bay. i will try and get a video of it to make it easier for you guys to hear and diagnose.

on the other hand ive discovered today i dont have a proper air filter! all it has is this sheet of fine material (looks like some kind of window mesh) just free to move around in there and it serves no real purpose filtering air because its not even sealed so its just moving around in there. so i dont feel safe driving it with that poor excuse of a filter. is there any other alternative rather than chasing down another filter or buying aftermarket ones? im flat broke atm and i need it to be fixed, i was thinking of getting some kind of breathable material and clamping it directly onto the carb for now. or is it fine to drive without a filter? seeing as most people put trumpets on them and dont seem to use filters at all?

cheers guys

[oz3litre]

Don't drive it without a filter! It will suck dirt in. Try and get an original from the wreckers. I wouldn't bother with anything else. Our local UPullit always has a 33 or two. I got one there. Alfa went to considerable trouble to put efficient filters on the cars and they breathe very well in my opinion. New paper elements for them are not hard to get or expensive. Don't put one of those cone filters on it. The factory one is designed to draw in cold air from the front of the car.

[oz3litre]

Oops! I just realized you have got a factory filter on it. Just track down a paper element for it. One of the members from your area should be able to tell you the best place to buy Alfa spares.

[77SudTi]

yes do use a proper paper filter.

The noise your describing could be caused by your ignition timing being too far advanced / lean fueling, technical term for the noise is pinging and can cause a metallic sound that you are describing but is heard on acceleration not deceleration...
Doubt it would be big ends as that sounds like someone hitting an anvil with a hammer wrapped in cloth, but can be more audible on deceleration than acceleration.

I'd say your motor needs a thorough service...oil change, plugs, tappet clearances, new ignition leads, fuel filter, ignition timing check with a timing light etc

The exhaust crackle is caused by valve overlap (which also gives that gruff sound) and lets some unburnt fuel into the exhaust on each cycle. I have noticed it can be increased and decreased with ignition timing changes. I also find that a properly tuned engine will not crackle and pop a great deal on deceleration, and with an unrestricted exhaust lets out a few big pops on gear shifts / deceleration.

[baldy]

When i lived in sydney 8 years ago i owned a 33 ti mk1 95bhp, the same car in england was called the 33 cloverleaf 105bhp both cars looked identicle i didnt know my self untill i had a drive in it, i thought it was underpowerd at first untill the guy who changed the cambelts in fivedock sydney told me it was 95bhp. i must have been the poshest backpacker in aus. hows this for a drive sydney all the way to cairns across to the norhern teratery down to adelaide across the great ocean road to melbourrn then the capital and back to sydney top drive took 10 weeks and the alfa never let me down once

[gti_rsi]

far out big drive indeed!

77sudti: i doubt its running lean, it smells rich on idle and blows a bit of black smoke on full throttle.

i would say the motor and carbs do need a tune up tho, it idles quite low at 650rpm.

i think the ignition has been retarded 3 degrees for the use of premium unleaded but i cant be too sure as the previous owner said that the motor had been converted to unleaded.

about the air filter, i will chase one up soon but the problem is i dont even have $1 to my name and im currently unemployed and seeking work, thus im asking if there is any alternative that i could use as a temporary filter, for example a piece of light breathable fabric/sponge (tightly clamped on of course) etc. i know it sounds silly but at least it would be a viable solution until i can afford to buy the proper sock filters. plus the sound of exposed carbs are just music to my ears.

[oz3litre]

I strongly advise sticking to the factory filter system. Sponge, sock, cone etc filters have been proven to be less efficient in air flow and much less effective in filtering out dust than paper ones. You will also definitely lose performance as a result of them sucking hot air from around the engine. My brother, who is a mechanic, has a neighbour who had a Holden V8 with an open K & N filter on it and he told the guy that the performance would improve of he put the factory one back on. He didn't believe my brother but decided to try it anyway, and was stunned as to how much better it was. Save your money for something else that needs doing to the car. Those engines with the Webers sound wonderful stock. My Alfa mechanic once put K & Ns on his Sprint and he said that the extra noise drove him mad after a while. Very few engines sound as nice as a stock Alfa boxer.

[Clayton105]

Its all in the cams. Some of you will know that the Ex-PM, big Mal Fraser was an Italian car fan. He brought a black Sud green cloverleaf in to Aus from the UK with the proper 105 bhp engine(this car was on Ebay about a year ago up in QLD). A colleague of mine at the last place I worked as a mech said that he used to service this car at Gulson's in Canberra. Said it went like a cut cat compared to the Aus ones. Everything was the same except the cams.

The air injection into the exhaust (by reed valves) causes very little reduction in power. I welded up these in my 33 4x4 thinking it would make it go better. The before and after power output was virtually identical. All it does is introduce air into the exhaust to ignite the unburnt fuel on the overun from the idle jets. The other tubes and hoses running from the bottom of the carbs to the top of the carbs are part of the crankcase ventilation system.... once again, no power lost here.

In fact, the quoted power for the 4x4 33 was 95 bhp, but surprise surprise, on the dyno yeilded the same as the TI: 58-ish kW. Convert this to bhp = 78, correct for losses (~ 78 x 1.2 = 93.6). Pretty close to the 95 bhp I said.

Running these engines without the air filter or just trumpets (without rejetting) results in a reduction in power. Once again, proved by experimentation on the dyno.

I had an '81 Sud that I put some 40mm IDFs on, ported the heads, nice seat job and put the Ti engine pipes on: 70 kW at the wheels. Man it was a fun little car. When I sold it these dudes turned up and started bagging it out: I gave them the keys and said go for a drive.... They could not give me the money fast enough when they got back.

P.S. If you are that broke: you should not buy an old Alfa!

[oz3litre]

Quote:

Originally Posted by Clayton105 In fact, the quoted power for the 4x4 33 was 95 bhp, but surprise surprise, on the dyno yeilded the same as the TI: 58-ish kW. Convert this to bhp = 78, correct for losses (~ 78 x 1.2 = 93.6). Pretty close to the 95 bhp I said. Running these engines without the air filter or just trumpets (without rejetting) results in a reduction in power. Once again, proved by experimentation on the dyno. I had an '81 Sud that I put some 40mm IDFs on, ported the heads, nice seat job and put the Ti engine pipes on: 70 kW at the wheels. Man it was a fun little car. When I sold it these dudes turned up and started bagging it out: I gave them the keys and said go for a drive.... They could not give me the money fast enough when they got back. P.S. If you are that broke: you should not buy an old Alfa!

[keith_h]

Yours is the TI referred to in the user manual as QV, Quadrfoglio Verde. It can be identified by the interior and the Speedline telephone dial wheels. I thought they came with a leather wheel as standard but the wooden tiller you have there looks the business.

You need to check the front suspension for cracks as a 33 of this vintage will almost certainly have them. The cracks needs to be repaired so you can fully enjoy the handling otherwise they do handle poorly and sometimes quite dangerously. Check the subframe as well above the driveshafts. Remove the washer bottle and have a good look as well and check at the bottom of the bonnet stay. PM me if you want the name of someone who can properly do any repairs if they are required.

Own an S1 33 - time to check for cracks

There are two options for the noise you describe. One is pinging. If you use regular unleaded your car will ping and this can damage the engine. Caltex Vortex has enough octane to stop the pinging and the car will run better. Get that sorted promptly. The other option is the exhaust backfiring on the over run which is the characteristic popping sound. It is supposed to do that.

It does sound like it needs a tune. There is no need to retard the timing for premium unleaded. That makes no sense. This car looks to be in nice shape, so find yourself a good Alfa mechanic, get the car checked and spend any money required to sort out any gremlins up front and enjoy.

Regarding which is best, we have both types here and they are both very good in different ways. Neither is really better than the other although the wagon (which has Ti trim, modified suspension and bigger engine) is the one I would pick for a serious drive anywhere.

[greku]

Quote:

Originally Posted by roban I wouldn't be to concerned about the big end bearings, if one of them is damaged you will hear a noise through out the rev range.

[keith_h]

Here in Australia regular unleaded causes pinging. Using premium unleaded which has more octane stops it. Maybe that could also be your problem.