Started by Ascari32, July 14, 2020, 09:40:13 PM
Quote from: sportiva on August 02, 2020, 07:28:27 PMwow! you can wear out tires/tyres in less than 3k Miles or 4.8k kilometers and you haven't been arrested you are very lucky.
Quote from: sportiva on August 03, 2020, 03:55:54 PM And to keep on topic at least the GM designed partially built? Holden V6 engine is of a 60° angle. not many V6's are 60° simply because most V6 cars over the decades were run down V8 production lines so a 90° V6 was just cheaper and easier to do. Even the Ferrari influenced V6 in the new Giulia is a 90° configuration.
Quote from: sportiva on August 02, 2020, 04:04:06 PMThe old AlfaSud plant were the last 159 was built is very close if not next door to the aviation division. I acknowledge and understand the history of the two plants and the radial engines alfa romeo built under the leader ship of Ugo Gobbarto were splendid examples of engineering.
Quote from: Ascari32 on August 25, 2020, 07:22:42 PMQuote from: sportiva on August 02, 2020, 04:04:06 PMThe old AlfaSud plant were the last 159 was built is very close if not next door to the aviation division. I acknowledge and understand the history of the two plants and the radial engines alfa romeo built under the leader ship of Ugo Gobbarto were splendid examples of engineering.The travails of this Enigmatic car continue! To be fair, it is not of Alfa's making - damn. It has more to do with the way I chose to modify my car. The manifold cats have gone. They are the metal type and clearly can withstand much higher temperatures. Although I knew the twin cats below the car are Ceramic and thus lower temperature, I felt as they are some distance away from the engine, they would probably cope ok. It was the output of the twin cats that appeared to be the problem as they form a "Clarinet Reed" for the gases exhausting into the central section where the resonator is. After my modifications, the higher power level was causing extreme droning @ ~ 2500 rpm. I fitted a Supersprint central section which has no resonator and sure enough, the drone disappeared. But this resulted in a cacophony of noise emanating from the rear boxes. Cue new rear boxes - a lot worse, although both the sound and acceleration from 3000 rpm is brilliant. But impossible to live with at below.My worst fears seemed to be confirmed - a new cat would be needed. And Supersprints is not cheap. So having bitten the bullet, I contacted Supersprint Technical Department. By this time, the Cat had been ordered, but I had the daunting prospect of having to buy yet another pair of rear boxes as the new ones seemed incapable of handling the power. I wanted Supersprints assurance theirs, which would complete my system once the cat is installed, would handle the extra power. I quoted a figure of 350hp as a target figure. I even picked up a brand new Alfa Nearside Box cheaply, fearing I would end up going back to theirs. It confused me, the Alfa boxes handle the lower revs well, but break up at higher revs, the new ones handle higher revs, but break up at lower ones. I needed Help.That's where S.S. tech dept. came in. I laid it out as baldly as I could and within the space of the weekend I had a comprehensive reply."It's not your rear silencers that are your problem, it's your cat". Brilliant, so at least I had a second opinion supporting my view about the Alfa Twin Cat".But not for the reason I believed. Quote:- "I would be very surprised if there are any cells left in them". They are 500 CPI (Cells per inch) and very restrictive.So to shorten a long story, having a spare twin cat in the garage - which I was intending to take to the dump - I got a garden chair to sit on, a 10mm. piece of stainless pipe, an eight pound club hammer and drove the pipe through the cat. Initially it was very reluctant but eventually smashed my way through. A quick check below and sure enough, there were pieces of the Ceramic Cat on the garage floor.I picked up, what clearly had been part of the outer matrix, which was very hard. The initial strength must have been this outer screen/matrix. However, along with it on the floor was part of the inner honeycombe. Inspecting that revealed it was almost of a dust consistency - extremely crumbly. One could rub a small lump between two fingers and it quickly fell to dust/coarse powder.So, full marks to the Supersprint tech guy for pointing me in this direction. I don't think the "Reed" helps, but if my twin cat has collapsed cells, it certainly would contribute to my problem.Funnily enough, after a quick blast to get out into mainstream traffic flow, from a junction yesterday, the exhaust system appears to have got a little less "Rackety". It's not the way it should be. But it seems a bit quieter. And although my doubts about my new rear boxes remain, the throttle response is such that, blipping the throttle a little on down shifts brings an exhaust note that reminds me of my old twin cam Berlina and her Dellorto carburettors.Funny - the tricks the mind can play on perceptions!!!!!!!
Quote from: Ascari32 on October 10, 2020, 09:42:10 PMThe Supersprint catalytic Converter has now been fitted to my 159 for about two - ish weeks. The Alfa boxes cope very well and it generally sounds very sweet, with no popping or farting on overrun. Just a good solid "Blat". But it still did not feel entirely right. At the same time as the cat going on, a failed rheostat was found and a replacement ordered. I thought I was faced with a very big bill for the climate control system; but no, the guys picked it up very quickly and temporarily the A/C is working. Although not quite feeling right, I believe when the rheostat is replaced, i will refit my new boxes again. I think that is only fair, before I consign them to the scrap heap/ebay. Prior to the S.S. cat going on, I was experimenting with different fuel grades, provoking management codes at will when swapping from RON 95 to 97. However, I had not cleared the codes when the cat was fitted. Subsequent to this, I disconnected the MAF, wondering if the slight lack may be due to the MAF, but no change. So I went and saw the guys and asked if they could just give the history file a once over and reset the alarms for me. There was a fairly substantial log to be cleared, all relating to Lambdas and MAF with a couple of cylinder misfires in the mix. Since the log has been reset however, that slight niggle about performance has evaporated. The engine is running beautifully. Silky smooth at low rpm and what is particularly noticeable is how smooth it is when pulling away and changing up. First and second have always been "Notchy" and not getting it right, the the revs would die off very quickly. Getting my timing right between first and second was crucial. But, because there is now so little drag on the engine - the engine gently dies - off the revs; as I dip the clutch, move from first to second and the re - engage. It really seems like a different car. Progressively it gets better 2nd to 3rd, 3rd to 4th. And fifth and sixth have never been a problem. Acceleration is strong, with no flat spots, revs rising very quickly, the car belying its weight. Exhaust, very throaty at low revs but I do miss the sound it makes with my new boxes over 3000 rpm. Not bad though and the Alfa boxes coping well. Noise levels are very acceptable - nothing like the original but acceptable. Tick - over solid but meaty. I cannot see that when the new boxes are refitted, it will be any quieter. So that mat be the sticking point. But it is worth a try. I shall have the front drivers side wheel bearing changed at the same time as the rheostat is done as that is the only untoward noise coming from the car. All in all, I love it. Next stop - heart in mouth - Dynamometer. But I will wait a couple of weeks, just building up the courage. That aside, what a fabulous car the 3.2JTS Q4 is - now!! P.s. The feeling of having lost a little at the bottom end has now gone, with good solid torque coming in, low down Always better than standard, it just seemed in the process of trying to resolve my exhaust/cat problems, a little was lost in the mix. Now, back to what it was - absolutely fine. Hope that feeling wasn't down to my new boxes. However, I will find that out when I refit them!!!
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