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PostPosted: Fri Oct 23, 2009 2:12 pm 
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Traditional non-turbo tuning is fun, but bloomin' expensive. I don't even want to think about how much I was spending to get 5bhp extra here and there out of my Saab 96 rally project. In the end it was making pretty nearly 140BHP from an engine that originally only had about 70. So good results, but my god what a lot of work, stress and money. :)

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PostPosted: Fri Oct 23, 2009 11:12 pm 
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Dave will be along with graphs later as he says however power on Wayne's rollers where it was mapped was 166.6 bhp. No torque figures other than a guess from Wayne as his rpm pickup was broken yet again.

A back to back test for reference purposes at Dastek's rollers in Chorley gave 162/163 bhp which was still actually climbing where the test stopped revving to (6450 rpm) and 140 ft lbs. Longer trumpets brought the torque in 500 rpm earlier and with a wider spread at the expense of a couple of bhp at the very top. Overall though they look like the way to go and Dave will change over to them later after a bit of welding so they can be used with the air filter.

Would have been nice to crack 170 bhp but the tubular exhaust manifold with the same diameter secondaries as primaries is definitely a bit odd and maybe not helping much. Nor I suspect are the tractor engine weight internal bits. However she pulls hard from 2250 (105 ft lbs) which is lower than I dared to hope for with what's essentially a rally cam and will drive around quite happily on part throttle right down to almost idle. It's the same profile as I use in 1905cc XU Peugeots for road rally use and pulls from about 3k in those. Clearly the Saab has a bit more engine capacity which will drop the rpm points and is maybe also being affected by the odd pulse tuning of the exhaust. Peak power on the long trumpets is at about 6400 and torque is fairly flat all the way from 4500 to 6500. She should definitely power round to 6800 or 6900 quite happily but the standard valve springs and heavy buckets might not like that and it wasn't tried on the rollers.

So basically now we just need to find out how the "proper" engine goes. This road engine's head has 44mm inlet valves (42mm standard). The proper engine has ultra big 46mm valves on big inserts, bigger exhaust valves, a bigger cam but still only rally spec, much lighter buckets, uprated valve springs and more compression ratio. Basically more track oriented than road although it should still be perfectly road driveable. Valve train should be fine to 7500 rpm or even more. In fact I think with hindsight (and actual power curves) we could have got away with even more cam to be honest but it's usually best to be conservative with cam choice and get a nice wide spread of power rather than something peaky and undriveable. I think we could also have gone up a bit on compression ratio but the last thing I wanted was for any detonation to rear its head. It's going to be on standard unleaded most of the time and also both engines only have the OE cast pistons.

However I guess 160/165 bhp at the first attempt in something which drives almost like a standard road car and pulls from 2250 to nearly 7k is ok to be getting on with. I remember back in the day watching fairly comparable 2 litre Ford Pinto rally engines coming in to the local rollers for setup and most of them wouldn't pull below 3k at all and few of them had more than 150 bhp. Too much cam and not enough attention to cylinder head flow basically. The head is always the heart of the engine. We're way past 145 bhp Saab turbo figures anyway. I'd like to see 175 bhp from the UBV head engine though.

Might be fun to do a proper race one. Forged pistons, lighter internals, race cam, big CR, high octane fuel, maybe a bit of time on the flow bench instead of just my best guess at port shapes. 200 bhp should be there or thereabouts.


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PostPosted: Sat Oct 24, 2009 7:05 am 
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Quality :D

And remeber folks this 8v "tractor" engine design started as a 1700cc design in the mid 60's.

Not too shoddy ;)


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PostPosted: Sat Oct 24, 2009 7:21 am 
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The BMW 6-pot is really old. That comes from some time like the 1930's or somewhere around then. Obviously BMW will have changed a lot since the original design... but the H engine isn't the first version of the trimumph engine either.

ejenner wrote:
217bhp at 8500rpm... agreed... not an H engine... but still... hows that for a target!

Image

sonett wrote:
Horses for courses, that engine would really only be any good for what it was made for, racing. As for the claimed bhp figure, i am not too sure.
B or H engine, there really isn't much difference as to what power they could produce.
Pumaracing wrote:
Might be fun to do a proper race one. Forged pistons, lighter internals, race cam, big CR, high octane fuel, maybe a bit of time on the flow bench instead of just my best guess at port shapes. 200 bhp should be there or thereabouts.
Maybe if you take the revs up far enough then you will get this output!?

This is the original manifold design for the 8v. There is another type of cast manifold but I don't think that would be worth bothering with.

Image


You can also get an aluminium flywheel for these engines.

Image


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PostPosted: Sat Oct 24, 2009 7:19 pm 
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Location: REMAINING UNFAITHFUL TO FACTORY STANDARD SPECIFICATIONS SINCE 1988
Car Model: OLD SAABS....NUMEROUS
HELLO DAVE(PUMA) AND DAVE (SONETT)......

AS THERE IS NO TUNING MANUAL FOR THE SAAB ENGINE,YOU HAVE BEEN ABLE TO APPLY A SIMILAR THOUGHT PROCESS,INCORPORATING FACTORS FROM THE PEUGEOT ENGINE.......

THE END RESULT SPEAKS FOR ITSELF.......SOME 10/15 BHP THEREABOUTS,UP ON MY RALLY ENGINE (ON TWIN DELLORTO 45'S),AND AROUND 10LB/FT MORE TORQUE.........THE BENEFITS OF ECU'S,THROTTLE BODIES,LARGER VALVES ETC

BEAR IN MIND,I AM ON STANDARD VALVE SIZES .....WITH POINTS AND A DIZZY.ALL COST ORIENTATED......
I HAVE GIVEN THE MATTER SOME THOUGHT,WITH DAVE(SONNET) AS TO WHETHER I SHOULD GO TO TWIN 48'S........BUT I THINK PERSONALLY,I WILL LOSE OUT ON SOME MID RANGE TORQUE,FOR THE BENEFIT OF A FEW EXTRA BHP,AT THE TOP END....

FOR THE 48'S TO REALLY BENEFIT MY ENGINE,I THINK LARGER VALVES SHOULD BE CONSIDERED.....?


I DO THINK,YOU ARE QUITE RIGHT IN BEING CAUTIOUS REVVING IT ABOVE 6500 RPM,WITH A HIGH LIFT CAM AND STANDARD VALVEGEAR :lol:

IT IS GREAT DAVE,THAT YOU FINALLY HAVE IT RUNNING ......... :wink:

CAN'T WAIT FOR THE RESULT FROM THE ''BIG VALVE HEAD''


CAN YOU STOP, MIDERING ME NOW.......... :lol:



AINTREE BECKONS,APRIL 2010.......IS IT REALLY A TURBO KILLER....?

INTRESTING STUFF,WATCH THIS SPACE.........


Attachments:
CAN THE THROTTLE BODIES KILL THE TURBO.......JPG
CAN THE THROTTLE BODIES KILL THE TURBO.......JPG [ 134.06 KiB | Viewed 1922 times ]
RALLY ENGINE ON TWIN DELLORTO 45.JPG
RALLY ENGINE ON TWIN DELLORTO 45.JPG [ 97.71 KiB | Viewed 1922 times ]
NATURALLY ASPIRATED TUNED ENGINES.........SETTING THEM UP TAKES THE TIME.JPG
NATURALLY ASPIRATED TUNED ENGINES.........SETTING THEM UP TAKES THE TIME.JPG [ 107.96 KiB | Viewed 1922 times ]

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PostPosted: Sat Oct 24, 2009 7:40 pm 
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ejenner wrote:

This is the original manifold design for the 8v. There is another type of cast manifold but I don't think that would be worth bothering with.

Image



EMMETT,DAVE HAS THIS TYPE OF FOUR BRANCH MANIFOLD FITTED(SIMILAR TO MINE)IN THE LAST PHOTOGRAPH....BUT HIS IS CERAMIC COATED

IT IS NOT A SAAB,STANDARD ITEM......

SOME TUNERS PREFER WEBERS TO DELLORTOS....YOU DON'T NEED TO CUT A HOLE IN THE BONNET FOR WEBERS...

THE SAAB RALLY 16V ENGINE HAD A SIMILAR EXHAUST MANIFOLD DESIGN......


Attachments:
1976 SAAB 16V RALLY ENGINE EXHAUST MANIFOLD.JPG
1976 SAAB 16V RALLY ENGINE EXHAUST MANIFOLD.JPG [ 51.76 KiB | Viewed 1919 times ]
carbsetup B ENGINE TWIN 45 WEBER.jpg
carbsetup B ENGINE TWIN 45 WEBER.jpg [ 56.38 KiB | Viewed 1919 times ]
FOUR BRANCH MANIFOLD OFF THE 99 RALLY...NOTE THE V PIECE WELDED ON TO PROTECT THE FLANGE JOINT FROM ROCKS.JPG
FOUR BRANCH MANIFOLD OFF THE 99 RALLY...NOTE THE V PIECE WELDED ON TO PROTECT THE FLANGE JOINT FROM ROCKS.JPG [ 47.7 KiB | Viewed 1919 times ]

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PostPosted: Sat Oct 24, 2009 9:07 pm 
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I thought he had a custom manifold actually. But I'll take a correction if not.


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PostPosted: Sat Oct 24, 2009 9:21 pm 
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ejenner wrote:
I thought he had a custom manifold actually. But I'll take a correction if not.


The manifold on my engine is a 4-2-1 MSS from the states, it's the only one that is currently available and as Dave has already mentioned, it could and probably is hurting power, due to the fact that the primary and secondary pipes are the same diameter.
Em, the pic of the 'Saab' 4 branch is not the original 8v manifold, you rightly said there is a cast manifold and this was the first type. The 'Saab' 4 branch is for the 900 only because you would have to cut some of the floor away for it to fit the 99, so it's of no use anyway.
I already have an aluminium flywheel fitted, of course this has nothing to do with horsepower.

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PostPosted: Sat Oct 24, 2009 9:47 pm 
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Really glad to hear some development of this thread and 162 bhp is a very respectable figure indeed! Moreso that, knowing Sonnet, this will be usable power. Forget the 99 Turbo, 162 is more than some 900 16v turbo varients! Drivable off boost, no turbo lag, less heat, less weight, less plumbing. All good stuff!


I've got a 16v ITB manifold and a pair of Dollorto 45 I've been dithering with and have been telling myself I really need ITBs and an ECU; in this months "Retro Cars" there is a Talbot Subeam running twin 55 carbs on an 2.7ltr straight 4 pushing out 327bhp!!!

Ok - it may have a 500rpm usable powerband and is only driven at WOT but there is more to life than turning up the boost and a remap'ed fuel chip!

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PostPosted: Sat Oct 24, 2009 9:56 pm 
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BIRDIEMANGO wrote:
HELLO DAVE(PUMA) AND DAVE (SONETT)......

THE END RESULT SPEAKS FOR ITSELF.......SOME 10/15 BHP THEREABOUTS,UP ON MY RALLY ENGINE (ON TWIN DELLORTO 45'S),AND AROUND 10LB/FT MORE TORQUE.........THE BENEFITS OF ECU'S,THROTTLE BODIES,LARGER VALVES ETC

BEAR IN MIND,I AM ON STANDARD VALVE SIZES .....WITH POINTS AND A DIZZY.ALL COST ORIENTATED......
I HAVE GIVEN THE MATTER SOME THOUGHT,WITH DAVE(SONNET) AS TO WHETHER I SHOULD GO TO TWIN 48'S........BUT I THINK PERSONALLY,I WILL LOSE OUT ON SOME MID RANGE TORQUE,FOR THE BENEFIT OF A FEW EXTRA BHP,AT THE TOP END....

FOR THE 48'S TO REALLY BENEFIT MY ENGINE,I THINK LARGER VALVES SHOULD BE CONSIDERED.....?


I DO THINK,YOU ARE QUITE RIGHT IN BEING CAUTIOUS REVVING IT ABOVE 6500 RPM,WITH A HIGH LIFT CAM AND STANDARD VALVEGEAR :lol:

IT IS GREAT DAVE,THAT YOU FINALLY HAVE IT RUNNING ......... :wink:

CAN'T WAIT FOR THE RESULT FROM THE ''BIG VALVE HEAD''


CAN YOU STOP, MIDERING ME NOW.......... :lol:



AINTREE BECKONS,APRIL 2010.......IS IT REALLY A TURBO KILLER....?

INTRESTING STUFF,WATCH THIS SPACE.........


Mmmm 10/15 hp more, i suppose it depends which rollers you have picked, Waynes dyno put your twin dellorto engine at around 144 iirc, so that's over 20bhp, if you use the dastek dyno its 17bhp. Peak power is not the be all and end all, it's under the curve that matters, spread of power and driveability, this was very important for me because i wanted this car to be a fast road car that i could use everyday. When i get round to it i'll sort out the graphs and with your permission your graphs also.

As for it being a turbo killer........in terms of power then yes, compared to a standard 99 turbo, this was initially my target. You will be able to try it for yourself, hopefully tomorrow :wink: then you can post up what you think of it.

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PostPosted: Sun Oct 25, 2009 9:50 am 
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:corn: :corn:





:corn:

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PostPosted: Sun Oct 25, 2009 11:03 am 
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Birdie has gone to look at some old cars somewhere, so his test drive will have to wait 'till next week.
Changing the ignition from disi to wasted spark was quite easy, once the toothed wheel and sensor had been fitted. With the disi removed this left a large hole at the end of the cam cover, i had a piece of square alloy plate that would cover the hole, i cut it to a rough shape and finished it off on the lathe. This then provided a good location for the coil pack.
I have since tidied up the wiring.
Image
Image

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PostPosted: Sun Oct 25, 2009 11:20 am 
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OK, time for some graphs. The first one is from Wayne Schofields dyno, his inductive pick up was not working so no torque graph, just a guess which was a bit on the high side. I did want to play around with the air filter and induction length at Waynes but we ran out of time.
Image

A few days later i took a trip to a dastek dyno in Chorley, i was then able to have a few power runs and make some changes.
Run No 3 was with the air filter and 40mm trumpets.
Run No 4 was with no air filter and 40mm trumpets.
Runs 5 and 6 with no air filter and 90mm trumpets.
At the expense of a few horsepower the 90mm trumpets gave the best allround performance, it brought peak torque in earlier by around 500rpm. To get the airfilter onto the longer trumpets requires the alloy filter base plate moving up and welding to the trumpets, i need to make sure i have enough space from the end of the trumpets to the back of the filter bar.
Image

Below is a graph of Birdies 99 EMS rally car, this was done at Waynes dyno, as you can see there is a nasty dip in torque at around 3600rpm. Waynes dyno appears to be ball park for power, the torque does seem to be high, it was the same with my Pug engine. When i see Birdie next i'll see if he still has the dyno chart from the dastek.
Image
Image

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PostPosted: Sun Oct 25, 2009 1:44 pm 
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I'm going to make a few comments on power and torque figures but firstly to Dave, is there any chance you could size your scans to no more than 800 pixels wide please? For people with antiquated old pcs like mine and 15" monitors everything scrolls off to the right of the screen, including the text, and to read anything I keep having to pan left and right which makes it a royal PITA.

Anyway, Wayne no doubt does a good job of setting engines up but the accuracy of his rollers proves to be suspect every time we check it. The power figures are not too far out but the torque ones are always massively overstated. On Dave's 1360cc Pug 106 built to an almost identical spec as another I did for a mate in Aberdeen Wayne gave it 145 bhp and 113 ft lbs. On the Dastek rollers in Aberdeen the other engine had 139 bhp and 99 ft lbs.

Same with the Saab on Wayne's rollers and Dastek ones. 156 ft lb at Waynes and 140 ft lbs at Dastek. Multiplying Wayne's torque figures by 0.9 puts you somewhere near an accurate figure. That would make the 148 ft lbs for the car above around a true 133.

I've been running some simulations of Dave's car's performance using the Dastek power curves on my vehicle performance simulation software. There are more details of how that works on my website for anyone that's interested. We have a few remaining uncertainties about exactly what the gearing is as there are some obvious errors in the Saab data sheets but it was checked at 18.4 mph per 1000 rpm in 4th at Dastek and I can work back from that to other gears.

One thing that became apparent is how the huge gulf between 1st and 2nd gear affects it. The rpm drop is so large that almost any tuned engine will fall out of its optimum torque band. That means you need to rev it way past peak power in 1st to try and minimise the rpm drop into 2nd. The other gears are closer together and the problem less acute.

Using 6800 as an rpm limit I get 0-60 in 8.9s, 0-100 in 25.8s and the 1/4 mile in 16.8s @ 85.7 mph. Top speed about 124 mph. I think that should give an 8v turbo a run for its money anyway. A closer ratio gearbox would really help this engine though. Using 6500 rpm as a limit loses a massive half a second in the 0-60 dash so you really do need to scream it to optimise the performance. It might even be worth fitting the uprated valve train for serious track work because the engine clearly wants to go past 7000 from the shape of the power curves.

Trying the prospective UBV head engine with an estimated 175 bhp and a 7800 rpm rev limit with the special valve train things change very radically and not just because of the few extra bhp. The much higher rev limit means it easily hits 60 in 2nd gear thus saving a gearchange and the rpm drop problem basically goes away too.

0-60 in 7.7s, 0-100 in 21.4s and the 1/4 mile in 16.2s @ 88.2 mph. Top speed 129 mph. That's into 16v turbo territory or not too far off it.


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PostPosted: Mon Oct 26, 2009 8:32 am 
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yeah, tractor-weight internals go with tractor-grade first gear ratio.

I spose it might be possible to find a different set of first cogs from one of the later or earlier gearboxes... or indeed a different set of second gear cogs so you can change that gap to the way you want it.

The Saab engine is baised towards slightly high revving with the oversquare setup. Could bore the cylinders and make it even further oversquare. Think 90mm is standard but this can go to 92mm. Saab did something similar when they created the 2.1 engine.


Can see here, my Saab 2.1 block... clearly larger diameter pistons over standard 2.0

Image


On my 99 turbo I have a similar problem with gear ratios where the engine will be off boost when changing between 2nd and 3rd... which is pretty poor really. I'm hoping to cure this by using the new ECU which I am acutally able to properly map compared with the Saab gear where I could only play with the fuel map. There are a number of other things I can do as well. For example, I can use a lower primary drive with an increased rev limit amongst other things. All good fun.


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PostPosted: Mon Oct 26, 2009 10:43 am 
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I did a bit of tinkering in the program to see how a close ratio box and higher final drive would affect things. A lot as I suspected. With the car geared for about 120 mph instead of 140, 1st and 2nd closer together and the rest spread more evenly the 0-60 came down to 8.2s, 0-100 in 24.6s and 1/4 mile in 16.5s.

That's still only revving it to 6800 so it would be quicker still with the special valve train.


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PostPosted: Mon Oct 26, 2009 10:59 am 
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Just for fun I put the car on a diet and removed 250 lbs of weight from it. I think that might be possible with no seats, sound deadening, spare wheel, maybe a bit of perspex and some drilling. I assumed the special valve train and let the computer decide where to change gear which it wanted to do at 7200 rpm.

Result was 0-60 in 7.5s, 0-100 in 21.6s and 1/4 mile in 15.9s. It's actually potentially a pretty quick car now other than the box and some spare flab. The UBV engine would be much quicker still.


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PostPosted: Mon Oct 26, 2009 11:16 am 
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ejenner wrote:
The Saab engine is baised towards slightly high revving with the oversquare setup. Could bore the cylinders and make it even further oversquare. Think 90mm is standard but this can go to 92mm. Saab did something similar when they created the 2.1 engine.


Whether an engine is oversquare or undersquare actually makes not a jot of difference to how it revs other than big bores let you fit big valves. All that actually matters is the airflow capability of the head. One of the "revviest" engine families you'll ever see, the Honda VTECs in the CRX and similar are quite undersquare - they just have very good 4v cylinder heads.

The concept that with a given cylinder head a long stroke engine has good low rpm torque and a short stroke one has good high rpm power is an old wive's tale based on fundamental misunderstandings of how engines really work.


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PostPosted: Mon Oct 26, 2009 1:48 pm 
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I am slightly ahead of the game with the box for the UBV head, i already knew the awkward spacing is not good. Original Saab competition gears have not been available for many years and second hand sets don't come up very often and those that do have seen better days, a company in Sweden offer a close ratio set for a few thousand pounds here is the link http://speedparts.se/index.html?/shop/p ... 9-93.shtml However, i have managed to put something together that will hopefully prove to be more usefull. I was fortunate enough to be offered a brand new competition spec 6:31 final drive for the 5-speed box, i will use the 1989-90 box (GM45612) but 5th gear intermediate will be changed from 14/34 to the 1981-88 15/34 gear. so the gears will be;
1st.....30/16
2nd....24/22
3rd.....20/28
4th.....16/31
5th.....15/34
Primaries 31:30.
Final drive 6:31

Basically this box will become a 4-speed box, because 1st gear will be quite useless, so 2nd becomes 1st etc, although i may have to alter the primaries to attain a higher top speed. There are 5 types of standard primary gears, each increasing or decreasing overall gearing by 6%.
Type 4 = 31:30
Type 5 = 30:27
Type 6 = 31:26
Type 7 = 32:25
Type 8 = 33:24

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PostPosted: Mon Oct 26, 2009 7:43 pm 
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...It's not an old wives tale... but the reason (which I'm sure you know) does not contradict your statement with regards flow through the combustion chamber... The difference is that a long throw stroke adds a lot more weight to the end of that piston as it flings to the end of its run around the crank. That's what creates the higher torque lower down. The oversquare engines rev better because the engine does not mind reving so high as the inertia is lower by design and not just the weight of the individual components.

Why would Saab bother making a 2.1 if it didn't make any difference? Valves were the same size. Intake manifold was larger. Dunno really. But food for thought.


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