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r_towle
Has anyone tried to build a flat 8 with two type 4 motors?

Theoretical questions.
Assumptions
2 motors each producing 100 HP and 100 Lb/ft of Torque

The motors are end to end, front to rear.
The cranks are fastened together either bolted or welded.

1) Would you get 200hp and 200 lb/ft or torque? or is there some multiplier...seems like you would produce more torque..

2) could it be done with a single ignition system available for sale off the shelf.

3) could you do it without two distributors? crank fired ignition system..I am thinking that there could be a wheel placed in between the motors to give you something to time from.

4) I am assuming either a nice FI system, or four carbs.

Has anyone done this?
I would like to see some articles or web pages if this has been done in the aircooled world...

Thanx in advance
Rich
Mueller
yep, a few have been done........I know I've posted pictures as a well as a few others....

for a 914 application, the motor wouldn't fit unless you moved the assembly back a few inches...even without the cooling fan, I don't think it would fit in the stock location

for the cost/time/ it would take to make one, there are a dozen better engine choices unless one just wants to do it for the novelty of doing it....

since it's already been done a few times, there is no novelty in it....nothing ground breaking....kinda boring IPB Image
sanman
I thought of it but I think it would be


too long to fit in a 914 and
you would loose 1 fan for cooling

now on the other hand If some one made a 6 case that took t4 or t1 P/C,rods, and heads it may work
but that just my thoughts

forget it! you would need a 6 crank, and cam
Just get a chevy v8 or a porsche 6 and be done IPB Image
r_towle
i was hoping you would answer...you always think outside the box...

So what about the torque numbers...is it simply double???

It just seems that is would be multiplied somehow..
and where would i find some pics....
Rich
andys
It's been done both ways. I saw a pic years ago of a specially cast block for 8 cylinders. Also, the Fittipaldi brothers raced a Bug in Brazil where they coupled two motors together similar to what you describe, in a mid-engined configuration. They were apparently very successful with this car. Interesting way that they ducted air to cool the motors: they slanted the windshield back into the driver compatment. Air was ducted over the driver, then down to the two motors.

Andy
r_towle
honestly cooling seems like a simple part of it ...
A custom horizontal system would work.

What are the numbers...in theory???

Rich
eeyore
Double displacement does not usually equal double torque or horsepower. Not sure why.

In WWII, Pratt & Whitney took 2 14 cylinder radials and joined them onto a single case, resulting in a 28 cylinder that made 50% more HP. In the '90s Honda simply upped the size of a 600cc four to 900cc and got 20% more power (50% more displacement). Granted, the stock T4 is restricted, so using a RAT 2270 as a basis, maybe 250 HP would come from a T4x2. Just guessing.
nebreitling
i would think that you could never get double the power. maybe 150%, 175% if lucky.

entropy's a bitch.
Jake Raby
Already have a print in with moldex on the crank.
Already dissected 4 engine cases to find the best mating points.... Just need time
machina
asked the same question a while back....

here's what I got.
eeyore
Hans Dahlbeck? Isn't he the brain donor in 'Young Frankenstein'? Seems fitting.
machina
QUOTE (Cloudbuster @ Jan 28 2005, 03:23 PM)
Hans Dahlbeck? Isn't he the brain donor in 'Young Frankenstein'? Seems fitting.

No, I think you mean Mr. Abby Normal IPB Image
BigD9146gt
You'd be better off starting with two early 2.0 911 engines. By cutting the center two cylinders out of one case and placing them in the center of the other case, you add two cyclinders to an already superior design. Having small cylinders to begine with (width wise) helps keep the lenth of the motor down too. Then a Scat crank and some custom cams, you have the better overhead cam design, better cooling, and better head flow. Plus with the early cases, they're all aluminum like the 914 case, making welding them together easier... and stronger.
Jake Raby
Nah.... Can't make a statement with a 911 engine!

Plus, they cost too damn much to play with at this level..

I'm using 964 heads though..

Engine will go in a mid engine 1961 VW Single cab truck, under the bed.....
r_towle
QUOTE (Jake Raby @ Jan 28 2005, 01:47 PM)
Nah.... Can't make a statement with a 911 engine!

Plus, they cost too damn much to play with at this level..

I'm using 964 heads though..

Engine will go in a mid engine 1961 VW Single cab truck, under the bed.....

I had a funny feeling you would be looking at this at some point in your life...

I may try to get this done, just to see if it can be done smoothly, easily, and if it has benefit.

I am thinking why not use the heavy strong crank and push rods, lighter cylinders and pistons, and turbocharge the whole thing....
It would be a cool way to use parts that may be inferior for a hopped up T4 motor, but rugged enough for a T8 motor.

Rich
Mueller
QUOTE
I may try to get this done, just to see if it can be done smoothly, easily, and if it has benefit.


if it was even one of those choices above, you'd see more than a few running around IPB Image

it'll have all of the same problems or issues a /4 has, the only benifit is if you are trying to reach a certain hp level...if stock /4 has 100 and you want 175, then the /8 should be able to give you 175 horsepower easier than the /4

I'm betting that hp per liter would be the same and if anything, the /8 would be under more stress if you try to push it too hard.....
jwalters
IPB Image An aviation supplier / builder / design company called "Able Experimental" has done this with full success--albeit a T1 engine---Developed over 210 HP and almost 280 ftlb of TQ---key was 90.5mm P/C and a 80mm stroke---it was made for experimental aircraft--the same company makes the altimizer carburetor--this is an injected carburetor which automatically compensates the mixture for changes in air density--very popular carb in aviation.
Jake Raby
It won't cost a whole lot for me to do it, other than the crank and heads... The rest of it I have gobs of....


Its all in time and putting the imagination to work..

Its no fun if you don't push the envelope.... I'm sure I'd learn something beneficial to my other normal engines from doing it!
Mueller
QUOTE (jwalters @ Jan 28 2005, 05:06 PM)
IPB Image An aviation supplier / builder / design company called "Able Experimental" has done this with full success--albeit a T1 engine---Developed over 210 HP and almost 280 ftlb of TQ---key was 90.5mm P/C and a 80mm stroke---it was made for experimental aircraft--the same company makes the altimizer carburetor--this is an injected carburetor which automatically compensates the mixture for changes in air density--very popular carb in aviation.

considering thier 100 hp /4 motors cost $6000, I'd hate to see the price of that /8 motor IPB Image

they do have some cool stuff...
jwalters
IPB Image Yea they do---imagine there is allot of machining and welding up a crank and cam and MAGNESIUM case ( Can you say,,sparkler??) Those engines require even more prep than or = to Mr. Raby does to his to make them a viable high power aero engine If the balances of the entire assembly are off more than .10 inches per second the crank will grenade itself--even at the max rpm of 3600 these engines are rated for--and bye bye propellor--the cranks are rough prepped by CB's--they actually forge a crank just for this purpose---kool stuff indeed

Don't know ifn I would ever get into something like that, manufacturing wise--the liability factor is an ass pucker!!!

But it would be kool to see Jake the man do it---400+HP anybody???

I myself have a really doable engine make-up I am dreaming of---it uses the stock bottom end--but the cyl and up is off the shelf from a manufacturer that has been in business since 1908--

Not going to reveal it yet,,need to get measurements and geometric values looked at--plus I don't want to get sand bagged just yet! IPB Image IPB Image
Bleyseng
screw two motors! put four of them together!
redshift
QUOTE (Mueller @ Jan 28 2005, 08:13 PM)
considering thier 100 hp /4 motors cost $6000, I'd hate to see the price of that /8 motor IPB Image

they do have some cool stuff...

Uhh... excuse me, but doesn't everyone's /4 run about $6k?

IPB Image

Sounds CHEAP for FLYING.


M
Bleyseng
I am hoping to squeeze by with $5000,
buying that Passat stole the rest of my milk money!
Jake Raby
Here it cost 6K for a stock rebuild, but you can add 50HP for another 2500 in most cases.

5000 will go a long way really soon, especially in the beginning!
r_towle
how would you do oiling on the rear engine???

Seems like you would have to eliminate the oil pump on the rear engine and connect the two oiling systems in some way...

Rich
Brando
or connect them at the cranks...

if you're going that far, might as well go the route of merging two 911 cases...
SpecialK
Screw pistons...........someone stick a Huey Turbine in a 914 (hey...I saw an Allison V12 in a Opel GT once....."point and shoot" as someone put it)
BigD9146gt
QUOTE (Jake Raby @ Jan 28 2005, 01:47 PM)
Nah.... Can't make a statement with a 911 engine!

Plus, they cost too damn much to play with at this level..

I'm using 964 heads though..

Engine will go in a mid engine 1961 VW Single cab truck, under the bed.....

911's cost too much to play with at this level??? IPB Image IPB Image IPB Image IPB Image IPB Image

1) What would two used long blocks go for? $2000?... ya, possibly more, but my friend just picked up a complete 69 911E all original with minimal rust for $1000. Deals are out there if you keep your eyes open, and thats what we're talking about.

2) If you charge $6000 for your base motor, and i was paying you to build a flat 8, you would have to charge $50,000 to even think about braking even. Odds are, if someone is going to be making something of this magnitude, they would't be paying you or anyone else to do it, cause for that price lots of other things could be aquired.

3) Lets think about how the factory made larger motors. The 908 and 917's for example, have very close relations to the 901 engine being over head cams, single heads, etc. Porsche and his crew were very brite, and if they chose a design similar to the 901 for their larger motors, i'm gonna say it wasn't because they listed all the options on the table and played spin the bottle to choose? Think about whats already done? Dry sump, single heads-better flowing, overhead cams, stronger crank, just a better-overall design from the get-go.

4)This is a project for someone who can do all their own work (like you and me).

Jake, i respect your work, but stick to what you know. Last time you were on the 911 bird forum, you started out high and mighty, but had zero answers. If you actually worked with 6's, you wouldn't say what you do about them... and i wouldn't be typing right now.

Again, you are a phenominal VW aircooled 4 cylinder guru.
Air_Cooled_Nut
Yeah, deals are out there if you wanna WAIT for them and are constantly searching for them IPB Image Anyway...

After reading about the Ferrari's and Lambo's that have eight plus cylinders and how folks drool over the carbed versions of these engines I think it would be something neat. Heck, you wouldn't need monster big jugs, either, as these cars didn't, just lots o' cylinders. My initial guess would be getting two balanced STOCK engines and make sure the timing 'tween the two engines was spot on, then mate 'em IPB Image From what I read, the older Ferrari eight cylinders run like two, four cylinder engines mated together, which also contributes to their distinct sound. I'm guessing their cylinder firing order is different than American V8's.

Now, getting a vehicle to accept the engine is another issue. But from my point of view I think it'd be neat and who gives a crap if it's already been done before? If you were successfull and DOCUMENTED it so others could follow you could develope a cult following IPB Image
jwalters
IPB Image Just do like the fiero / lambo conversion guys---stretch that puppy and put a flat 12 lambo in it!!!

THAT would be kool to say the least---- IPB Image
r_towle
ok,

When if any was the earliest time that an overhaed cam was used on a /6 motor???

I have never taken one apart....yet...

Rich
DuckRyder
Thinking out loud:

Couldn't you slice one case disecting it between the bores (that would require an angle or zig zag) IPB Image

then slice the ends off of the other case to insert it in between the front and back of the other two halves. IPB Image

That make sense? IPB Image

IPB Image IPB Image
r_towle
QUOTE (DuckRyder @ Jan 30 2005, 04:18 PM)
Thinking out loud:

Couldn't you slice one case disecting it between the bores (that would require an angle or zig zag)  :sawzall:

then slice the ends off of the other case to insert it in between the front and back of the other two halves.  :welder:

That make sense?  :blink:

IPB Image  :burnout:

ok, ill bite, why would i do that versus cutting the back off one and the front off the other.......

BTW It looks like the oil galleys can line up if it is cut in the correct place.

I would go with a dry sump.

Rich
BigD9146gt
Rich, before i start in on Air Cool'd, the 901 (911) was an overhead cam from the get-go. They had some drawings for a single cam like the TIV, but it didn't prove itself like the overhead cams. The first 911 was in '65, but the project started in about '60. It wasn't set in stone till '63 or so, because Porsche wasn't sure if they wanted to go with a 356 looking car or not. Granted the 911 is close to the 356, they had other designs that they were looking at. Also, there was the 356 Carrera engine, which was the 4 cam motor back in the early '50s (550 spider). They the 901 had its first twin cam race engine in '67 for a few of the 911R's, which were 2.0L with around 200bhp.

QUOTE
Yeah, deals are out there if you wanna WAIT for them and are constantly searching for them IPB Image  Anyway...


Ok, whats your IPB Image point? Isn't that the point of a "good deal", or are we thinking like typical americans who want a good deal 365 days with no effert or quality?

QUOTE
After reading about the Ferrari's and Lambo's that have eight plus cylinders and how folks drool over the carbed versions of these engines I think it would be something neat.  Heck, you wouldn't need monster big jugs, either, as these cars didn't, just lots o' cylinders.  My initial guess would be getting two balanced STOCK engines and make sure the timing 'tween the two engines was spot on, then mate 'em IPB Image   From what I read, the older Ferrari eight cylinders run like two, four cylinder engines mated together, which also contributes to their distinct sound.  I'm guessing their cylinder firing order is different than American V8's.


Ya, its called a 944 and a 928... The only difference is the crank and block. Same heads, pistons, rods, etc. But just because it has half the cylinders doesn't make it easy to make over. I too don;t know what the firing order is, but a 6/8 cylinder engine is WAY more naturally balanced than a 4 cylinder engine. In fact, the 6/8/12 cylinder engines are the the best for being balanced.

QUOTE
Now, getting a vehicle to accept the engine is another issue.  But from my point of view I think it'd be neat and who gives a crap if it's already been done before?  If you were successfull and DOCUMENTED it so others could follow you could develope a cult following IPB Image


Cults are for those who like Coolaid. If a project like this ever made it to production, there would be very few who would undertake it. Just like Mr. Polopulus (sp), the guy who took the 901 and chopped two cylinders off and made a 4 cylinder for the 356 croud. The motor is around $15000, but that croud spends more money than the 914 croud.

I'm not by any means saying use the 901 because its expesive, but to the same measure, don't use a TIV because its cheap. Your going to be spending money either way you look at it, so why not start with a better designed engine and parts?
DuckRyder
QUOTE (r_towle @ Jan 30 2005, 08:37 PM)
QUOTE (DuckRyder @ Jan 30 2005, 04:18 PM)
Thinking out loud:

Couldn't you slice one case disecting it between the bores (that would require an angle or zig zag)  :sawzall:

then slice the ends off of the other case to insert it in between the front and back of the other two halves.  :welder:

That make sense?  :blink:

IPB Image  :burnout:

ok, ill bite, why would i do that versus cutting the back off one and the front off the other.......

BTW It looks like the oil galleys can line up if it is cut in the correct place.

I would go with a dry sump.

Rich

Hey, I said I was thinking out loud. IPB Image

I thought that it would match up better that way - possibly.

It has been a while (thank god) since I've seen one bare though.
URY914
Here's what you need...
redshift
QUOTE (Special_K @ Jan 29 2005, 07:18 AM)
Screw pistons...........someone stick a Huey Turbine in a 914 (hey...I saw an Allison V12 in a Opel GT once....."point and shoot" as someone put it)

That car was on Ebay..

LOL Paul! Is that your new class ride?



M
r_towle
QUOTE (URY914 @ Jan 30 2005, 06:09 PM)
Here's what you need...

looks kinda heavy to me.

I know you looked at it and said, hey he could make it lighter if he did this and this and this....

Rich
URY914
QUOTE (r_towle @ Jan 30 2005, 06:14 PM)
QUOTE (URY914 @ Jan 30 2005, 06:09 PM)
Here's what you need...

looks kinda heavy to me.

I know you looked at it and said, hey he could make it lighter if he did this and this and this....

Rich

I've been working like crazy on my car. I gotta get it back together enough to take it to Sebring in two weeks to get it weighed. My day job and family keep getting in the way IPB Image

Paul
Air_Cooled_Nut
QUOTE
Ya, its called a 944 and a 928... The only difference is the crank and block. Same heads, pistons, rods, etc. But just because it has half the cylinders doesn't make it easy to make over. I too don;t know what the firing order is, but a 6/8 cylinder engine is WAY more naturally balanced than a 4 cylinder engine. In fact, the 6/8/12 cylinder engines are the the best for being balanced.

IPB Image Okay, ya lost me. What's yer point? My bit on the Ferrari wasn't a suggestion of how to fire it but as to a contribution to its sound.

QUOTE
Cults are for those who like Coolaid[sic]. If a project like this ever made it to production, there would be very few who would undertake it.

I meant it like people doing it themselves for fun, not to actually make a production engine that people would buy.

QUOTE
Your going to be spending money either way you look at it, so why not start with a better designed engine and parts?

I agree with this logic. But I guess my message was too subtle as I was thinking about the SOUND of a multi-cylinder, carbed air-cooled engine.

I'm not denying that a 901 engine is likely a better candidate from an engineering standpoint so here, this one's on me IPB Image IPB Image
jwalters
Wonder how the T4 would respond with a crank that has throws at 90 degrees at each other--instead of the 180 degree config---this and change the firing order to reflect a burn event on one side of the engine at a time--like : 1, 3, 2, 4

Instead of one side-followed by two same side, then last one side again---: 1, 4, 3, 2---

There would have to be a radically ground cam for this--


Ala Ducati--if the Duc had four cylinders.......
bondo
QUOTE (jwalters @ Jan 31 2005, 01:47 PM)
Wonder how the T4 would respond with a crank that has throws at 90 degrees at each other--instead of the 180 degree config---this and change the firing order to reflect a burn event on one side of the engine at a time--like : 1, 3, 2, 4

Instead of one side-followed by two same side, then last one side again---: 1, 4, 3, 2---

There would have to be a radically ground cam for this--


Ala Ducati--if the Duc had four cylinders.......

I don't think you could grind a cam THAT radically, as 2 lifters are riding on each lobe, one for each side of the engine. By design it has to be 180 degrees apart.
r_towle
yes, but what if you welded up the two motors to be in the 90 degree position???

That is what I was thinking....

Rich
DuckRyder
QUOTE (jwalters @ Jan 31 2005, 04:47 PM)
Ala Ducati--if the Duc had four cylinders.......

Trying to make a desmo valve system work without overhead cams would be ... probably impossible.

Once you've adjusted the valves on one, you won't ever try to convert something TO Desmo.

And there is a 4 cylinder Ducati, the DesmoDeci (vs DesmoDue)

IPB Image

IPB Image

DuckRyder IPB Image
jwalters
Very nice pic of a Duc!!! I am spanking to it right now----always wanted one--900SS super light was the one that I lusted for--

I did not mean use the valvetrain--no--I was thinking of the inherent smoothness of a 90 crank--but because the cylinders are still 180 deg. the extra two throws would balance out like it was a 90 deg. crank in a 90 deg. cylinder layout-

And yes-those cam lobes would have to be whittled down in width quite a bit--but it could be done......
DuckRyder
QUOTE (jwalters @ Jan 31 2005, 07:52 PM)
Very nice pic of a Duc!!! I am spanking to it right now----always wanted one--900SS super light was the one that I lusted for--

God, I wish I had never sold my 96 900 SuperSport SP! IPB Image

Back to your regularly sceduled thread... IPB Image
JmuRiz
I know were're getting off topic here, but mmmmmmm Desmosedici = very nice. Man are they fast in testing this year too, wow. Looks like another fun MotoGP year.
BigD9146gt
Nathan, I second that! MotoGP sould be great this year!

Duck, good point!!! Even though the Desmo is an awsome working system, the adjustments that are required to keep them up to spec are extreamly time consuming.

Its like the early 356 Carrera 4 cam motors... book time is 40hours!! I'm not kidding. They figured it would take you 3 times to get it right... Its all bevel gears and shafts, first you adjust the exhaust cam, then the intake cam. Pro's know how to compensate so that once they tighten the intake cam gear, the exhaust doesn't move. The good thing is once the adjustment is done, you never have to adjust it again solong as nothing breaks!
Al Meredith
I was out at Chuck Beck house (he lives outside Atlanta now) last fall and the first thing I saw was a 4 cylinder 911 engine he built. I can't remember when he did it but I would say early 80's. I also have an old HOT VW's Mag from the "energy crisis" days where they built a 2 cylinder Ty1. I think there is an aero ty 1 engine that runs 2 cylinders on the same side.
Mueller
QUOTE (Al Meredith @ Feb 27 2006, 05:34 PM)
I was out at Chuck Beck house (he lives outside Atlanta now) last fall and the first thing I saw was a 4 cylinder 911 engine he built. I can't remember when he did it but I would say early 80's. I also have an old HOT VW's Mag from the "energy crisis" days where they built a 2 cylinder Ty1. I think there is an aero ty 1 engine that runs 2 cylinders on the same side.



you can buy a 2/3 911 engine brand new now.....bring money, I want to say just the bare block casting (new) is $10K or something crazy like that....
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