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Discussion Starter #201 (Edited)
You're courting trouble - you'll have Alfaitalia on your case, HaHa!

But I'm puzzling over this cat problem. I have found a Audi A8 (4.2) cat which rated at 360 bhp. My idea is to bin the Alfa twin cat for this single cat.

I could then combine the two flex - pipes from the Autodelta Manifolds, fabricating a nice "Y - Union" into the single A8 cat. On the output, fit the two lambda probes, either side of the pipe from the cat.

Looking at the way the Alfa one is designed, the Lambdas are virtually in same position in any case with just the "Clarinet Reed" separating them. I just need the dimensions of the A 8 cat. It could make a neat solution. and it should get up to temperature as both banks will be heating it.

P.S. - a bigger cat so it could reduce restrictions even more, which would be helpful.
 

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Nah....I used to have to have one of those "£100 MOTs" on my unsilenced, race tyred , no lights (not actually an MOT failure if used only in daylight hours) Suzuki GSXR......but he would never let anything safety related go through. The bigger issue is if you get stopped by a roadside check....all to bloody common around here....might be different on your patch. That would be a grand fine for no dpf or cat (depending on petrol or derv of course) I don't want to pay. Personal choice really.

PS.Is it just me that "cut and paste" doesn't work for since the forum "upgrade"?
 

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Discussion Starter #203
PS.Is it just me that "cut and paste" doesn't work for since the forum "upgrade"?

Just you, by the look of things - normally me!
 

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Discussion Starter #204
You're courting trouble - you'll have Alfaitalia on your case, HaHa!

But I'm puzzling over this cat problem. I have found a Audi A8 (4.2) cat which rated at 360 bhp. My idea is to bin the Alfa twin cat for this single cat.

I could then combine the two flex - pipes from the Autodelta Manifolds, fabricating a nice "Y - Union" into the single A8 cat. On the output, fit the two lambda probes, either side of the pipe from the cat.

Looking at the way the Alfa one is designed, the Lambdas are virtually in same position in any case with just the "Clarinet Reed" separating them. I just need the dimensions of the A 8 cat. It could make a neat solution. and it should get up to temperature as both banks will be heating it.

P.S. - a bigger cat so it could reduce restrictions even more, which would be helpful.

Found this 3 way Cat on the Web. I think this is an easier option than having my current Siamese Cat modified. It is rated for N/A engines up to 4.7 litre so I think it should be big enough. And If I screw it up - the damage at £97 isn't going to be too painful. But if it solves the problem of that damned drone - that will do me!

I still have my Man - Cats but I cant see them ever going back on the car. And I can't think there is a second hand market for them.

2.25" AP Exhaust Heavy Load Catalytic Converter True OBDII - 608215
 

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Discussion Starter #205
Just done a little more research on Cats as I am concerned that I may have bought one (TWC) which is more restrictive than the Alfa "Twins". However, it seems :-

Three-way[edit]
Three-way catalytic converters (TWC) have the additional advantage of controlling the emission of nitric oxide (NO) and nitrogen dioxide (NO2) (both together abbreviated with NO
x
and not to be confused with nitrous oxide (N2O)), which are precursors to acid rain and smog.[18]

Since 1981, "three-way" (oxidation-reduction) catalytic converters have been used in vehicle emission control systems in the United States and Canada; many other countries have also adopted stringent vehicle emission regulations that in effect require three-way converters on gasoline-powered vehicles. The reduction and oxidation catalysts are typically contained in a common housing; however, in some instances, they may be housed separately. A three-way catalytic converter has three simultaneous tasks:[18]

Reduction of nitrogen oxides to nitrogen (N2)

  • 2 CO + 2 NO → 2 CO2 + N2
  • hydrocarbon + NO → CO2 + H2O + N2
  • 2 H2 + 2 NO → 2 H2O + N2
Oxidation of carbon monoxide to carbon dioxide

  • 2 CO + O2 → 2 CO2
Oxidation of unburnt hydrocarbons (HC) to carbon dioxide and water, in addition to the above NO reaction

  • hydrocarbon + O2 → H2O + CO2
These three reactions occur most efficiently when the catalytic converter receives exhaust from an engine running slightly above the stoichiometric point. For gasoline combustion, this ratio is between 14.6 and 14.8 parts air to one part fuel, by weight. The ratio for autogas (or liquefied petroleum gas LPG), natural gas, and ethanol fuels can be significantly different for each, notably so with oxygenated or alcohol based fuels, with e85 requiring approximately 34% more fuel to reach stoic, requiring modified fuel system tuning and components when using those fuels. In general, engines fitted with 3-way catalytic converters are equipped with a computerized closed-loop feedback fuel injection system using one or more oxygen sensors,[citation needed] though early in the deployment of three-way converters, carburetors equipped with feedback mixture control were used.

Three-way converters are effective when the engine is operated within a narrow band of air-fuel ratios near the stoichiometric point, such that the exhaust gas composition oscillates between rich (excess fuel) and lean (excess oxygen). Conversion efficiency falls very rapidly when the engine is operated outside of this band. Under lean engine operation, the exhaust contains excess oxygen, and the reduction of NO
x is not favored. Under rich conditions, the excess fuel consumes all of the available oxygen prior to the catalyst, leaving only oxygen stored in the catalyst available for the oxidation function.

Closed-loop engine control systems are necessary for effective operation of three-way catalytic converters because of the continuous balancing required for effective NO
x reduction and HC oxidation. The control system must prevent the NO
x reduction catalyst from becoming fully oxidized, yet replenish the oxygen storage material so that its function as an oxidation catalyst is maintained.

Three-way catalytic converters can store oxygen from the exhaust gas stream, usually when the air–fuel ratio goes lean.[19] When sufficient oxygen is not available from the exhaust stream, the stored oxygen is released and consumed (see cerium(IV) oxide). A lack of sufficient oxygen occurs either when oxygen derived from NO
x reduction is unavailable or when certain maneuvers such as hard acceleration enrich the mixture beyond the ability of the converter to supply oxygen.

Credit to Wikipedia for the above information.

However, in the full article it leads me to the conclusion that, given Lambda, when MOT -ed, was 1.004, 14.75:1 AFR, in closed loop conditions, perhaps the cat I have bought may be helpful in maintaining good emission control. I am still puzzled about the way Alfa placed the narrow band probes in the "Collector". Essentially, due to even the slightest back pressure from the silencer which follows, they are seemingly sharing the same pipe. So I may be over - anxious about having to physically place them in the single output of the replacement cat unit.
 

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Discussion Starter #206
I have Just delivered my old 3.2 JTS to Scholar Engines for stripping down and assessing any major problems with regard to a re - build. But this engine will be sold with the reground original, balanced crankshaft, or new balanced one, plus one new con rod. It is going whole or separate block and heads. Rings and pistons will be checked. If anyone is interested in it after cleaning and assessing then do let me know.

I would recommend Scholar for the rebuild as they do build competition engines, they do not charge the earth for their services and their knowledge and expertise is in my opinion second to none.

However, whilst waiting to organize the dynamometer run I have been doing some calculations on the work undertaken so far. I have been given some figures as to what to expect and on the basis of a median figure, these are the anticipated changes I expect from my modifications/Camshafts/Manifolds. Accepted this is a new engine, but I am basing it on my old one which failed at Bruntingthorpe.

RPM Original Power Revised Power Revised Power with Manifolds.
2250 92.1 BHP 105.92 BHP 113.92 BHP
2750 112.57 BHP 129.46 BHP 137.46 BHP
3500 143.2 BHP 164.70 BHP 172.70 BHP
4500 197.07 BHP 226.62 BHP 234.62 BHP
6000 251.33 BHP 289.03 BHP 297.03 BHP
6670 266.20 BHP 306.70 BHP 314.70 BHP

For those interested, the salient figure is a conservative 15% torque increase across the range and a quoted figure of recovered losses from the Autodelta Manifolds of 8 BHP. It remains to be seen what the Dynamometer results will bring however.
 

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Discussion Starter #207 (Edited)
I have Just delivered my old 3.2 JTS to Scholar Engines for stripping down and assessing any major problems with regard to a re - build. But this engine will be sold with the reground original, balanced crankshaft, or new balanced one, plus one new con rod. It is going whole or separate block and heads. Rings and pistons will be checked. If anyone is interested in it after cleaning and assessing then do let me know.

I would recommend Scholar for the rebuild as they do build competition engines, they do not charge the earth for their services and their knowledge and expertise is in my opinion second to none.

However, whilst waiting to organize the dynamometer run I have been doing some calculations on the work undertaken so far. I have been given some figures as to what to expect and on the basis of a median figure, these are the anticipated changes I expect from my modifications/Camshafts/Manifolds. Accepted this is a new engine, but I am basing it on my old one which failed at Bruntingthorpe.

RPM Original Power Revised Power Revised Power with Manifolds.
2250 92.1 BHP 105.92 BHP 113.92 BHP
2750 112.57 BHP 129.46 BHP 137.46 BHP
3500 143.2 BHP 164.70 BHP 172.70 BHP
4500 197.07 BHP 226.62 BHP 234.62 BHP
6000 251.33 BHP 289.03 BHP 297.03 BHP
6670 266.20 BHP 306.70 BHP 314.70 BHP

For those interested, the salient figure is a conservative 15% torque increase across the range and a quoted figure of recovered losses from the Autodelta Manifolds of 8 BHP. It remains to be seen what the Dynamometer results will bring however.
Popped up to engine builders, after telephone call informing me, they have a list of parts needed for my 159, 3.2 JTS engine.

New crankshaft and bearings - got them.

Two Con - Rods spun; replacements needed, got one but at £200 a pop - ouch!

Six new gudgeon pins needed - where the hell do I get those?

Set of new rings - pistons and bores ok apparently. Rings £900 + vat from ALFA.

Head overhaul kit, £180 per bank, but that seems good value as it includes valve seals, gaskets, etc, etc.

New oil pump - Mace best on market, price and quality wise.

Front and rear oil seals, gallery plugs and at least two cam roller followers.

Bearing cap bolts and head bolts.

Block checked for alignment - good. Heads checked for distortion -,good.

Decision needed soon. Some serious thinking needed.
 

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Maybe ask Mace about the piston rings. Or your engine builders might have a catalogue where they can order them in based on size alone, rather than ordering them from Alfa. You could also try Total Seal piston rings, we've used them before on Bussos, and affectionately called them Total B*stard piston rings! But they are good.
 

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"Six new gudgeon pins needed - where the hell do I get those?"

I've only ever bought gudgeon pins with pistons.....I thought they may be matched to them for clearance?????
 

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Discussion Starter #210
Maybe ask Mace about the piston rings. Or your engine builders might have a catalogue where they can order them in based on size alone, rather than ordering them from Alfa. You could also try Total Seal piston rings, we've used them before on Bussos, and affectionately called them Total B*stard piston rings! But they are good.
Thanks for that. Early days but found a new Brera/159 Con Rod on E bay last night - £69 -00p. I feel like a winner already - !!!!!!????
 

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Discussion Starter #211
"Six new gudgeon pins needed - where the hell do I get those?"

I've only ever bought gudgeon pins with pistons.....I thought they may be matched to them for clearance?????

I couldn't say. But Scholar give a comprehensive warranty to any engine they rebuild and when I spoke to them yesterday they said they always change the rings and pins. If I ask them to re - check for me, and I choose to re - use, the risk is then down to me. But I shall pursue the replace route in the hope that something turns up - just like the con rod.

However, I will have the pistons and con rods "shaved" again for balance. I have heard so many people say manufacturing tolerances are so good, there is no need for balancing. However, I think that is untrue. This will be the third time I have had everything matched and there is a tangible difference, not just at high revs. Second harmonic amplitude exists and there is little one can do about them. But by balancing everything, it ensures their amplitude is equal on all cylinders so the engine sounds sweeter, at all revs.

My engine is still behaving impeccably - well it threw another lambda code yesterday. But oil remains clean as a whistle.

I keep listening to the videos of 939's Brera Exhaust and the Special Camshafts Video and I am not sure if I should pursue this publicly any more. I am still trying to figure out how to record a video and perhaps I shouldn't. Because, there is such a difference between those two cars and mine. I have already told C.B. I think that video does them no credit because of the "Clatter". And I am convinced it is due to the engine inertia overwhelming the chain tensioners -particularly the primary one. But it doesn't matter as that affects both banks equally.

I have studied the timing chain system over many, many months, even been shown modifications to Ford Tensioners for the very same reason. Spoken to authoritative individuals who also state they cannot work the way they are intended. If you drive like a Granny, yes. But who the hell owns an Alfa to drive like that? I wonder if the timing chain system holds up better on auto boxes than on manuals?

Anyhow, I am grateful to Ken and 939 as it is now clear the drone is caused by the poor union at the output of the twin cat and the "Clarinet Reed". But mine is much more pronounced now than it was when I first got the car. But despite this, it sound like a completely different engine. Ignoring the drone - is it what I wanted - what I expected?

I suppose, I could be trying to justify the cost by saying yes! And believe me, given what it has cost me, it would be a bitter pill to swallow, if that were true. But, that I am contemplating rebuilding a second engine - my old 159 engine - should say something.

Driving normally, away from 2500 rpm, one can have a normal conversation and the engine doesn't intrude - difficult to notice it is there. The Busso, is always present - puts a smile on the face where ever it is on the rev range. Not this! Docile! Unobtrusive - pedestrian even! But powerful in the lower regions - urban speeds. It is so quiet, one may choose to listen for the usual aches and pains a 14 year old car should have. One could hear a pin drop, in the boot!

But I am still cautious about higher revs - just yet. But it keeps inviting them. Its bloody lovely! And, beyond 2500 rpm, the exhaust note is intoxicating.

It is better than the Busso! There is no need to change gear with either engine. But with the Busso, ultimately it starts to fade at the top end. This beast does not! If it was possible to shorten the stroke of this engine, to something like the 2.5 Busso, I swear it would rev to 11 - 12 k. The justification for these comments are based on Bruntingthorpe, with the original 159 engine. The driver at the time said it just did not want to stop. And the Dynamometer plot showed the torque dipped a little at the top end and was recovering by the end of the run. The slight dip; Auto-delta said, was probably not due to a slight miss - fire, but a resonance in the inlet track - Jano knows his stuff!

And this was before I fitted the C.B.'s and the Auto-delta manifolds. All I wanted to do was get the engine temperature down!!!!!!! Oil remains like new and temperature is still well down.

And still I think there is room for improvement. So I need to think hard about where I go with this engine now - the 159 that is. The VVT's are still not quick enough for me - not that anyone would notice. But I have long thought of how to isolate the VVT system from the rest of the lubrication system. So I may be forced - to satisfy my curiosity and go ahead with the rebuild regardless - just to "lay another ghost".

It is difficult - no - nigh on impossible to provide for every function that requires lubrication, hydraulic pressure and flow rate (VVT System), from a single source. Even BMW recognised that with separate pumps for each half of their V's by way of high pressure pumps, for the VVT System. That is why I bought a couple of Vanos pumps from one of their V10's. But how to do it with the Holden Engine? I'm not calling it an Alfa any more.

Well the idea is to provide oil, under constant/regulated pressure, via the front bearing cap - into the inlet VVT Solenoid, down to the head NRV's, having removed them and up to the exhaust VVT Solenoid. The feeds to the NRV's, from the block, will be blanked off - one less job for the engine oil pump to perform. If the drilling, which exists at the moment, also carries the feed to the camshaft bearing caps and the hydraulic tappets, then the Vanos pump can serve them as well. So there is even less work to do for the engine oil pump fitted to the crankshaft.

So, can all the expense incurred to date be justified? At 73 and with my health, not really. But, is it justifiable to right - off a huge chunk of money on a new Giulia, simply because a company provides the funds to do so, knocking it on when time is right to get yet another? Is that what being an enthusiast means now? My brother in law has a huge allowance or a car, being a director of a successful company. But he owns a van and provides three cars for his wife, daughter and son in law. And drives a Ford SUV, whatever it's name is. And has a bit left over for something he loves. Those cars will come an go, but he will always find money for what he really loves. It doesn't have to be a Brera. It could be an MG or a Ford Escort. But there has to be something worth devoting a little money and effort too! Without having an eye to a profit all the time.

"There is no Profit, in a life without the love of something or someone along the way".

When the Giulia goes; is replaced or is simply the last Alfa, who then will keep them going? Some talk so affectionately about the Brera, the 159, the Giulietta's and Mito's as a means to retain as much value in them for when they come to sell, yet have little or no interest in what Alfa's really are all about. There is Giulia V6 engine on E bay for about £4500, with very low mileage. I suspect that will be there forever - no one will want to take that on. Not even a group of individuals with presumed genuine interest would stretch their devotion to the Marque that far!
 

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However, I will have the pistons and con rods "shaved" again for balance. I have heard so many people say manufacturing tolerances are so good, there is no need for balancing. However, I think that is untrue. This will be the third time I have had everything matched and there is a tangible difference, not just at high revs. Second harmonic amplitude exists and there is little one can do about them. But by balancing everything, it ensures their amplitude is equal on all cylinders so the engine sounds sweeter, at all revs.
I've got two rebuilt Bussos, one 3.0 lightened & balanced with GTA cams, and the other a 3.2 which has just been balanced. On both occasions the full rotating assembies were span up to 10,000rpm and the out-of-balance factor was reduced by over 90%. Both engines feel very smooth compared to a stock Busso and I can only think it will give the bearings a much easier life.
 

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Discussion Starter #213 (Edited)
Encore!

First attempt at a video and it is long and pretty boring. But not as long as it took to get the engine back in and running.

However, I wanted to demonstrate it from cold start. people can make their own minds up about it. But she is as clean as a whistle and absolutely no hiccups whatsoever from the off. Took her to approaching 7 thousand. I am very pleased with the way it has gone so far - will pop down to have this alarm checked - think it is another Lambda code. It was heavy rain and misty yesterday and see from the mot the AFR is within spec, but close to the limit. so wonder if the damp - threw the code after starting and slowly reversing up the drive - has something to do with it?

Anyhow, hope this video has been attached properly.
Nope - that didn't work - back to the drawing board.
 

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Discussion Starter #214
Encore!

First attempt at a video and it is long and pretty boring. But not as long as it took to get the engine back in and running.

However, I wanted to demonstrate it from cold start. people can make their own minds up about it. But she is as clean as a whistle and absolutely no hiccups whatsoever from the off. Took her to approaching 7 thousand. I am very pleased with the way it has gone so far - will pop down to have this alarm checked - think it is another Lambda code. It was heavy rain and misty yesterday and see from the mot the AFR is within spec, but close to the limit. so wonder if the damp - threw the code after starting and slowly reversing up the drive - has something to do with it?

Anyhow, hope this video has been attached properly.
Nope - that didn't work - back to the drawing board.
This is getting worrying! since last posting, I have found a set of Brera pistons, with rings and gudgeon pins, 22,000 miles of wear for a sensible price. It now seems, the only things outstanding are peripherals - bolts, gaskets and oil pump. There is a bit of wear on the rocker arms/rollers, but I have also found a set of those at a sensible price.

Could it be, that those that hold stock and hitherto charged a fortune for parts, realise, so many cars have been scrapped that they will end up with parts no one wants? I hope so - the greedy bastards.

So the prospect of rebuilding my 159 engine is becoming a lot more financially viable than I when I first set out to re - build my Brera engine!

On the basis of how my 159 performs - is it worth it? Probably no! But there again - maybe. Would the rebuilt, modified 159 JTS go into my GTV????????

Now to overhaul the VVT Phasors/sprockets - again! Camshafts are shagged however! Besides, I wouldn't want to use them. Shyte is the best way of describing them!
 

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Discussion Starter #215
This is getting worrying! since last posting, I have found a set of Brera pistons, with rings and gudgeon pins, 22,000 miles of wear for a sensible price. It now seems, the only things outstanding are peripherals - bolts, gaskets and oil pump. There is a bit of wear on the rocker arms/rollers, but I have also found a set of those at a sensible price.

Could it be, that those that hold stock and hitherto charged a fortune for parts, realise, so many cars have been scrapped that they will end up with parts no one wants? I hope so - the greedy bastards.

So the prospect of rebuilding my 159 engine is becoming a lot more financially viable than I when I first set out to re - build my Brera engine!

On the basis of how my 159 performs - is it worth it? Probably no! But there again - maybe. Would the rebuilt, modified 159 JTS go into my GTV????????

Now to overhaul the VVT Phasors/sprockets - again! Camshafts are shagged however! Besides, I wouldn't want to use them. Shyte is the best way of describing them!

Just delivered new crankshaft, bearings and two new Connecting Rods to Scholar.

The engine is now stripped down and has been through hot washed/de-greasing. I have to pinch myself that this engine has done 112,000 miles. However, valve seats are pretty good, and all in all the heads look amazing. Except for some light scoring on the camshaft bearings.

The Block, mounted on an engine stand is unbelievable. The cross hatching on the bores is still clearly visible, with no discernible wear on any of the six cylinders.Pistons and rings are excellent.

But there is wear on gudgeon pins, with some slap. So they can't go back. No matter, I have found a further four New Connecting Rods for a good price. So this engine goes back together with a full pack of new parts - rings included, which I found at a sensible price. I intend to photograph the rebuild, to provide a record for any would be purchaser.

Given the new crank has already been balanced, it now requires pistons and Con Rods to be weighed and shaved. And she will "Sing like a Top", just as my rebuilt Brera does.

However, the crankshaft is beyond redemption and number one and two bearings and con rods are in a hell of a state. I expected it to be cylinders five or six. But no, the consensus of Scholar, who build and race engines is, oil starvation/surge! Unquestionably due to high revs on the Parabola at Bruntingthorpe. I will post some pictures of to illustrate the damage.

But the very first thing that sprung to our minds was - "Thank Christ the Brera Sump has now been baffled!" And the oil pick - up has been modified and lowered - which must be worth approaching a litre in sump level, before exposure.

I shall have the 159 sump modified and baffled as well. But this will be sold separate to the short block. The heads, I shall be retaining to further modify the oil feed to the VVT system, to increase their speed further.
 

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Discussion Starter #217 (Edited)
What sort of revs and what gear were you in whilst on the Parabola at Bruntingthorpe to cause the failure in the first place?
Er!!!! 7200/300 rpm - up and down between second and third. At those revs, the sump just empties, exacerbated by oil being forced away from the pick - up. Not good. But at least the engine did not explode. Bloody amazing the condition it is in, with the exception of the crankshaft and the con rods.

One of the big ends of either cylinder one or two,is actually worn oval. The other, the shell folded in upon itself. there is a couple of chunks taken out of the con rods where they interfered with the rotating crank - any more and it probably would have snagged, seized and pushed a rod through the side of the block.

I am going to be quite smug and say that when the oil pressure recovered - after starvation - it was sufficient to restore a little lubrication to the worn parts, such that they weren't completely dry. Then I think the engine management took over and killed the ignition.

Fabulous Block - unbelievably strong. And after my initial travails, a lot easier to rebuild than a Busso. Who needs cam locks, when everything is "Printed"on the Parts"?

"Any rev restriction?", says driver.

"No", says I, "What's she doing?"

"7200/7300 rpm". says he! "Doesn't want to stop".

Well it did!!!!
 
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