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T

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Discussion Starter #1
There have been a couple of threads on this forum about supercharging.

I was having a sort out of old books today, and came across a book entitled: "Turbocharging & Supercharging" by Alan Allard. The book is dated 1986, but I don't suppose much has changed since then.

Anyway, if any of you guys are seriously trying out a supercharging project and would like the book, you are welcome to it - First come, first served.

I can post it in the UK.
 
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Discussion Starter #2
There's a guy here who turbocharged his 8v- which is unusual since most people would (and have) chuck the TS engine and lumped something turbocharged and Japanese in the engine bay.

Don't know how well a high compression TS engine would take to turbocharging though...... how did they drop the compression ratio?

Might be worth a look.

Cheers

Amir
 
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Discussion Starter #3
Supercharging is really a waste of time, especially on four cyl motors-

My friend had a centrifugal sprintex blower with the reduction gearing forcing 18psi into a 1.8T Nord motor (75 factory motor but in an Alfetta GT- http://www.hitman.hm/alfablown.htm- my mechanic's old V6 Sedan is there too if you look around- I now own the motor in it).

This has since been returboed, and the jump in power at the same boost level is huge.
OK OK Sure it now runs a Motec ECU, and has had the piping redone, and also, the turbo is quite large for a small four cylinder (its a Garret GT25 with .84 front ARs on it), but the difference @ 18psi is 100hp @ the wheels.... a full 70kw of power.

Its not especially hard to turbo any motor, its just not cheap- the right way is to get custom pistons made up- Cosworth make blanks, which I can get here for around $1200AUD made into any compression ratio I want- I have an 8v TS that I wanted to start building on the side, with 7.5:1 pistons and O Ringed liners.... but I want to do something a little different.
 
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Discussion Starter #4
Ralf's Garden Shed book of Motah's says:

"Steal your sister's new Clairol hairdryer and rig it up so that it blows cold air into the inlet when the ignition's on. The ECU will sort out the fuelling. Ideally she will have chosen a hairdryer with a variable speed setting, so you can dial in more boost for those tricky "Saxo" moments".

Ralf S.
 
T

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Discussion Starter #5
I haven't got a 13A socket in my 155 for the hairdryer. Was this a factory fitted option? :D
 
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Discussion Starter #6
Mac OSX- Because making UNIX user-friendly is easier than debugging Windows
Slowhand, this from Computer Shopper this month:

From Computer Shopper:

--------------------------------------------------------------------
CHIP OFF THE BLOCK

Time to put on a tie and read the Apple News.

There isn't much and what there is is gloomy. Adobe Systems, maker of
Photoshop, Illustrator and InDesign, has stunned the Mac community by
revealing (some would
say trumpeting) that in lab tests the fastest Pentia and Athlonae are
blowing the fastest Macs out of the water. This from a company whose entire
reputation was made writing applications for the Mac, in the long ago when
Intel boxes just couldn't do that wild graphic stuff.

Apple is fuming about ingratitude and biased tests, but there's no reason to
doubt Adobe's integiity. What is open to question is its motive. Is Adobe
cutting adrift? Not likely: 25 percent of allAdobe sales go to the Mac
community. Or is it a warning shot across the bows? Face it, old pal, you're
falling behind. Never mind the crap about caching – you're on your ass in
the speed stakes, so deal with it or die.

Apple is raging because it knows this is true. If proof were needed,Apple's
latest effort – some flavour of G4 PowerMac – is the fastest Mac yet. Its
clock speed is 1.45GHz, up a whole 0.2GHz from the last fastest Mac yet.
Quick, my heart pills! Even the Mac magazines are shuffling their feet with
embarrassment over this one.

What's wanted from Apple right now are 2.5 gigs, not 1.5, yet I doubt
whether the rumoured new wave of Macs due in September will even approach
this. I will go further: if the September Macs bust two gigs, I'll eat my
keyboard.
 
A

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Discussion Starter #7
You can get 12-240v inverters real cheap these days, I got one last year for about £20.

Now where did the wife put that hairdrier?

:D
 
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Discussion Starter #8
I emailed a guy(can,t remember the company)about fitting a saab 9000 turbo the the 155 8 valve,he said the alfa 8 valve engine is a strong one and would take it without too high a boost no problem.
Regards
Shug
ps.wayne was his name
 
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Discussion Starter #9
--------------------------------------------------------------------
CHIP OFF THE BLOCK

Time to put on a tie and read the Apple News.

There isn't much and what there is is gloomy. Adobe Systems, maker of
Photoshop, Illustrator and InDesign, has stunned the Mac community by
revealing (some would
say trumpeting) that in lab tests the fastest Pentia and Athlonae are
blowing the fastest Macs out of the water. This from a company whose entire
reputation was made writing applications for the Mac, in the long ago when
Intel boxes just couldn't do that wild graphic stuff.

Apple is fuming about ingratitude and biased tests, but there's no reason to
doubt Adobe's integiity. What is open to question is its motive. Is Adobe
cutting adrift? Not likely: 25 percent of allAdobe sales go to the Mac
community. Or is it a warning shot across the bows? Face it, old pal, you're
falling behind. Never mind the crap about caching ? you're on your ass in
the speed stakes, so deal with it or die.

Apple is raging because it knows this is true. If proof were needed,Apple's
latest effort ? some flavour of G4 PowerMac ? is the fastest Mac yet. Its
clock speed is 1.45GHz, up a whole 0.2GHz from the last fastest Mac yet.
Quick, my heart pills! Even the Mac magazines are shuffling their feet with
embarrassment over this one.

What's wanted from Apple right now are 2.5 gigs, not 1.5, yet I doubt
whether the rumoured new wave of Macs due in September will even approach
this. I will go further: if the September Macs bust two gigs, I'll eat my
keyboard.
[/QUOTE] [/QB][/QUOTE]

Let's just stick to the 155s for the time being mate. The clown who wrote this is trying to compare clock speeds on different processors. It's like saying a 155QV is better than a Boeing 747 and if Boeing starts putting twinspark engines in the 747 he'll eat his keyboard.

Macs hit supercomputer status 3 years ago with the 15 Gigaflop (billion floating point operations per second) PowerMac G4 (running at 500 Mhz). Intel are still years away from that.

We can go on forever with this- leave me a private message on here if you want more info on this point.

In the meantime, if anyone has any ideas (I'll consider anything- even forced induction) about spreading the torque curve on my 8v below 2500 rpm so I'm not left for dead by Renault Espaces if I'm caught in the wrong gear, I'm listening.

I'm a big fan of forced induction- my previous car was a Mitsubishi Cordia with a 2 litre 16v turbo (4G63 for the techies) engine putting out 220hp and some 235lbft of torque. Could leave most things for dead- in a straight line. My Une Cinque-Cinque will make it look pretty stupid in a corner tho. If I could have both the power/torque of the Mitsu and the handling of my Alfa I'll be one happy man.

Cheers lads

Amir "turbo 'em" Isa
 
T

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Discussion Starter #10
Let's just stick to the 155s for the time being mate.
LOL! I'm no expert on the subject, BTW, just found the article amusing.

I thought there was a good analogy with Alfa enthusiasts, though. I love my Alfas, espcially my 155, and wouldn't dream of buying a BMW for example, but I also am aware that on most counts the Alfa is the inferior product. So in a way I'm the Mac user of the car world.

I'll probably be bounced off the forum for that comment, but hey what price free speech? :D

I am interested in the subject though, as both sides of the PC/Mac debate seem to get very hot under the collar about it. I've left you a PM as you suggested.
 
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Discussion Starter #11
Back to the original subject (prior to the techie invasion - when did you last get out of your bedrooms guys?):

I was having a sort out of old books today, and came across a book entitled: "Turbocharging & Supercharging" by Alan Allard. The book is dated 1986, but I don't suppose much has changed since then.
Much has changed in the turbocharging of road cars since those days. Back then it was all big turbos and loads of lag all bagged up into a naff looking and built Ford hatchback with a penile size spoiler somehow balanced in the bootlid! Now it is such a refined art that you'd hardly know the turbo was there, other than the large kick in the back whjen the right foot goes down!
 
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Discussion Starter #12
Must admit i dont quite understand why supercharging is a waste on 4 cly engines, since all you are doing is increaseing the capacity of the engine, makes no odds how many cylinders it has. For road cars, ie ones that are not flying round tracks at 7000rpm, superchargers are a much simplier , reliable bolt on piece of equipment.
All depends what you want to do with the car i suppose and you right how much money you have to throw at the job
 
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Discussion Starter #13
Look at the difference in power between the 2.0litre NA engine and the Q4. A nice increase I would say. OK, the engines are different, but both 4 pot........

Marlon
 
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Discussion Starter #14
Actually I must admit that Malaysians are a bit of an authority on forced induction.

We have utterly ludicrous road tax rates out here which are pegged to the engine capacity of the car. Anything under 2 litres is pretty cheap- 2 litres cost about 400 Malaysian dollars a year (1 sterling = 6.39 malaysian) and it goes crazy after that.

The 3 litre 164 I'll be replacing my 155 with in about a month's time will cost me 2,200 malaysian a year.

A 6.75 litre Rolls costs about 18,000 malaysian a year.

So with this crazy road tax rate (AND a very expensive toll highway network), people like me have taken to turbocharging and superchargin in a big way- especially since the rally blokes thoughtfully produce lots of homologation 2 litre turbo engines.

I have to say that you get pretty good results out of even a 2 litre 4 pot- at least the Japanese seem to. 200 odd hp and lbft ain't half bad for a 2 litre rice burner. It's how it's done that counts. New high pressure low inertia turbines have helped keep boost and power levels up whilst keeping lag down- almost unnoticeable nowdays.

Having said all that a blower is what my 155 ain't got and I sure miss the awesome torque spread I used to get out of the Mitsu. For the moment the pleasure of being able to chuck it thru most corners is making up for it somewhat.

I still reckon that 1986 book of Vish's will be worth a gander.

Cheers

Amir
 
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Discussion Starter #15
If it's any use to you, I can post it over.

There are weird tax regimes all over the world. It's getting that way here in the UK as well, but I remember years ago when I working near Milan seeing a Ferrari 208GTB turbo (as opposed to the 308GTB normally aspirated we had over here). Pretty much similar performance to the 308, but I don't know what the turbo lag was like.

It's interesting that you say the lag is almost unnoticeable, but how does the throttle response compare to a normally aspirated engine?

My only experience turbo engines is driving a Porsche Turbo (930 I think was the model number) and a Lancia Integrale. In both cases, I didn't like the lag at all. But these are both old cars, so as you say, things may well have improved.
 
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Discussion Starter #16
Supercharging is waste of time on four cyls for a few reasons-

How much torque does the average four cylinder produce?
Well it is obviously dependant on compression ratio and cam stats, but lets say under 200nm- around 180nm naturally aspirated- and probably running 10:1 compression.
So you have aircon, alternator, water pump and god knows what else sapping torque and hence, power and driveability from your motor, then you throw another belt on there in the hope of making more power, and your poor crank pulley has to spin it too! Belts are for holding your pants up!

It sounds great- forcing air into your motor, but with blowers youre losing torque to gain it- you will never match a turbo for torque. Or response.
I personaly believe lag is what happens when you incorrectly size a turbo for an application- my friends BMW 2002 Turbo has 6.5:1 compression and runs nearly 30psi boost. It will achieve 8psi boost in fifth gear @ 60km/h and around 1/8th throttle. Where is the lag in that?

And now while bolt on kit form is good because you dont want to spend much money, and you want a good result- kits like Those BMW ones are absolute shite- anyone about to tell you to put boost into a motor with 10:1 or even 11:1 static compression is a ********!

M3s with superchargers- its crap- they run 11.3:1 and you effectively turn it into a hand grenade- albeit safe because the factory knock sensor is so good, it takes the timing right back to stop the motor from destroying itself. Meanwhile the supercharger pumps boost in there and you get a little more power and torque from it, but not enough to risk blowing up your motor.

Anyway- Ive learnt to be scepitcal of the bolt on industry, and their ridiculous power claims- and unfortunately, the majority use superchargers as part of those claims because they are easy to fit.

Dont get sucked in.
 
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Discussion Starter #17
Well you obviosly know you engines, and proberly a lot more about forced induction than i do, but the graphs i have froma four pot motor with the sprintex eupercharger on are pretty impressive: -

the torque curve goes vertical at 1700rpm to 140 lb ft then peaks at 4200 rpm at 165 lb ft and stays at that level to 6800rpm ( like an over turned bath ), the power curve is very linear and peaks at 190 bhp at 6800 rpm. The engine is a 1600 ford crossflow, which would maybe make 70 bhp in standard form. The engien did have reduced compression ratio for the supercharing, but still , not half bad...

Most of my interest in foced induction came from a book i read by Alexander Graham Bell. At 450 pages long, he goes right through all the pros and cons of forced induction, both blowers and turbos, and how to build engines to suit them. But its very clear that for road cars (race cars are a very different matter) the blower has far more to offer, intstant response, torque at all revs, and so easy to control. Turbos on the other hand have none of these good points, but they do make lost of free power once there spinning at the right speed
 
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Discussion Starter #18
Mmmmmm seems he has a bee in his bonnet about something....from my own experiances a supercharger delivers power a lot smoother than a turbo ever can, lag or no lag..!!!!!
 
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Discussion Starter #19
Erm..... the point about the superchargers is true...... and no one will dispute that they're not as efficient as turbos in pressuring up the manifold. That's the tradeoff for the smoother power devlivery: You lose a little power to make a lot of power.

With turbos it's power all the way but you pay for it with lag. It's almost imperceptible now, but quite thrillingly noticeable especiallly with the older Mitsubishi rally engines which were long-stroke, low compression engines. The long stroke gave you enough low down torque that the car could respond well to throttle input at low revs anyway and keeps pulling well to where the turbo really spools up and gives you one heck of a mule's kick up the backside. Lots and lots of fun!!!

I'd love a look at your book, vish....... any idea what the postage will be or maybe you could sent it to my sister or one of my mates in Manchester and they'll send it over to me.

Cheers

Amir "blow 'em" Isa
 
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Discussion Starter #20
Don't worry about the postage. Send me a PM with your address and I'll get it off to you.

At least I know it's going to a good home :D -better than taking it down to the local charity shop, anyway. I don't suppose there are many old dears in Surbiton who are interested in supercharging their shopping trolleys.

Thanks for your PM about the Macs, BTW.
 
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