quote I got your answer. Two trannies, one for each wheel.

I seriously thought about that but each engine would have to put out the EXACT same amount of power/torque at the EXACT same RPM. Very unlikely. Plus if one engine had a failure--talk about torque steer...

quote I hope this thing makes it to the street with success.

Yeah, me too.

OK, I'm about to disagree with EVERYONE in this thread.

THERE WILL BE ABSOLUTELY NO PROBLEMS AT ALL with his initial drivetrain configuration.

What puts Busa power to the ground in the motorcycle? A chain. What is he proposing to link the two engines? A chain.

Anyone who says the engines need to be "synchronized" doesn't know what the hell he's talking about.

Just clutch and shift at the same time and you'll be fine. Sounds like you have that figured out as well... However, I wouldn't make it so easy to shift the transmissions independently from the cockpit. In fact, I think that the mere ability to shift them independently from the cockpit will give you MUCH more trouble than if you do it this way: Mount the engines solidly to each other and use a hard linkage between the transmissions. If one transmission somehow gets into a different gear than the other, then just take loose one end of that hard llink, get them back in the same gear and reattach.

I think that you're choice of FD's is what will need the most work. What chain ratio does a Busa typically use? I think you're going to need an FD well into the 4's to get the kind of acceleration that you want. If you can hit 60 in 1st with "only" 350 really peaky HP, your low speed acceleration (read: every day driving) is going to be sluggish.

For an interesting comparison see: http://dpcars.aprsworld.com/

He mentions using two engines sharing a common crank. Also, his car should be much lighter than what you are proposing.

2006 dpcars dp1 -- Projected first customer delivery February 2006

See the DESIGN LOG for the full story of the three-year long dp1 design process.

SPECIFICATIONS and PRICING:

All versions:

Wheelbase 80.5", Width 70", Length 113", Height 39" (top of rollbar), Ground Clearance 2.5"

Proprietary AWD system with Polychain GT2 belt drive and Quaife limited slip differentials

Wheels 13x8, Tires 225/45-13 R compound or 20x8 race slicks

dp1/s: $59K

Engine: Stock 1300cc Suzuki Hayabusa, 4cyl, 180hp.

Weight: 750lb. Power/weight 528 hp/ton (4.1 lb/hp)

dp1/t: $67K

Engine: Turbocharged 1300cc Suzuki Hayabusa, 4cyl, 265hp. Garrett GT28 ballbearing turbo 6psi

Weight: 775lb. Power/weight 752 hp/ton (2.9 lb/hp)

dp1/v: $85K

Engine: Custom 2600cc V8 based on two Suzuki Hayabusa motors on common crank, 360hp.

Weight: 850lb. Power/weight 931 hp/ton (2.4 lb/hp)

------------------
FierOmar

[This message has been edited by FierOmar (edited 08-06-2005).]

Impressive. Tossing you a positive for inovation.
Good luck.

quote I think that you're choice of FD's is what will need the most work. What chain ratio does a Busa typically use? I think you're going to need an FD well into the 4's to get the kind of acceleration that you want. If you can hit 60 in 1st with "only" 350 really peaky HP, your low speed acceleration (read: every day driving) is going to be sluggish.

Did you see the gear charts I posted? The S2K is not considered a slow car and my setup is lighter, has more power/torque at any given RPM and has the same overall 1st gear ratio (including tire diameter). The Busa has a primary reduction in the trans of 1.596. That combined with a 3.15 diff will yeild a 5.027 final drive.

The engines will be solid mounted and I thought of using a hard linkage between the shifter arms but if one mis-shifts then I am forced to stop and wrench on the car rather than just shift the stubborn trans into the correct gear.

Fiero owners are crazy...

but then, they come up with the most unusual and intersting ideas and modifications i have ever seen. this one being right up there. Good luck with this interesting project

268 GT
This is a great idea!
BTW I have seen a Website that has a Kit for this engines swap.

I can't remember where though... Keep the good work, and show more pics!

JG

Just curious. What front facia do you have on your car?

[This message has been edited by 86fierofun (edited 08-06-2005).]

quote What front facia do you have on your car?

It's the Artero fascia and front fenders from PISA.

That's crazy!

so is it done yet??

quote Originally posted by 268 GT: The engines will be solid mounted and I thought of using a hard linkage between the shifter arms but if one mis-shifts then I am forced to stop and wrench on the car rather than just shift the stubborn trans into the correct gear.

Is there a way to run a separate linkage that will work only one trans when needed?
Then you could get one to neutral and shift the other to match.
A sequenizing shifter so to speak. Or use a sliding connector that you can just disconnect one
trans from the shift linkage. From there it wouldn't be hard to get them reset.
If they have neutral indicator lights, I'd wire em both in to the dash. It wouldn't hurt to be able to
monitor engine vacuum for both either. If not two guages, then a balance guage indicator (vac). Then you would be
able to tell the load on each.
I don't think tuning would be much different than for multiple carbs.

All this reminds me of when we mounted 2 chain saw motors on a go cart, just no trans.
Youth has its moments.

TG

The idea is to not have to get out of the car, IE track days, auto-x, etc. The "T" handle will have a locking pin to hold them together that can be removed if necessary.

quote so is it done yet?

Not quite...

quote Originally posted by 268 GT: Did you see the gear charts I posted? The S2K is not considered a slow car and my setup is lighter, has more power/torque at any given RPM and has the same overall 1st gear ratio (including tire diameter). The Busa has a primary reduction in the trans of 1.596. That combined with a 3.15 diff will yeild a 5.027 final drive. The engines will be solid mounted and I thought of using a hard linkage between the shifter arms but if one mis-shifts then I am forced to stop and wrench on the car rather than just shift the stubborn trans into the correct gear.

Actually, I consider the S2K a slow car. It has more than 10# for every pony.

When I opened this thread, I thought it was another one of those "do you think it's possible" threads. Then I saw your pics!

I'm throwing a + your way for putting your idea into practice, and I too want to see the videos of the finished product!

Keep up the good work!

quote Originally posted by 268 GT: Id you see the gear charts I posted? The S2K is not considered a slow car and my setup is lighter, has more power/torque at any given RPM and has the same overall 1st gear ratio (including tire diameter). The Busa has a primary reduction in the trans of 1.596. That combined with a 3.15 diff will yeild a 5.027 final drive.

Wasn't aware of the inner workings of 'Busa transmissions. Got a link to a cutaway or something?
I still think you're going to want more gear.
What are the transmission ratios?
What chain ratio to Busa's run?

[This message has been edited by Will (edited 08-09-2005).]

10800 RPM redline

Gear Ratios:

1st-2.615
2nd-1.937
3rd-1.526
4th-1.285
5th-1.135
6th-1.043

Primary reduction-1.596

Secondary reduction (rear end)-2.35

[This message has been edited by 268 GT (edited 08-09-2005).]

Wish the 282's gears were that tightly spaced.

How many #/hp in the 'Busa? How many in your Fiero? I still think you're going to need a steeper rear end ratio.

Not trying to get in an argument here but how much TQ does the 2.8 put out? Isn't it ~170 or so? That would be a bit less than 150 WTQ correct? The twin busa setup will have 150 WTQ by 3500 RPM and hold it all the way to redline with a peak of 180 WTQ at 7500 RPM. The 2.8 has 140 HP which is about 105-110 WHP. The twin busa setup will have 110 WHP at 3500 RPM, 200 WHP at 5750, 250 WHP at 7000, 275 WHP at 7500, 300 WHP from 9-10,000.

I think it will do just fine. I could go with a higher numerical ratio but I want a hint of fuel economy on long trips to the track etc. This will put me at 5200 RPM at 75 MPH, right in the middle of the rev range.

Again, not trying to argue with you. I appreciate your input.

[This message has been edited by 268 GT (edited 08-11-2005).]

Here is a quick idea for the dash. Each piece is sized correctly relative to the 13" OD steering wheel. The speedo and tachs are 3 3/8", the oil pressure is 2 5/8" and the rest are 2 1/16".

from left to right:
volt meter
water temp
driver side engine tach
driver side gear position indicator
pass side gear position indicator
pass side engine tach
fuel level
speedometer
oil pressure
oil temp

[This message has been edited by 268 GT (edited 08-13-2005).]

You might want to look into a different set of tachs. as far as I know most bikes today have a redline of 12k-13k, and the one you are using goes around 11k I think

Man keep those pictures coming!

JG

10800 is the redline on the Busa engines. The needle should be able to swing past the "10" so it won't be a problem. The only tach I found that went to 11 was a Defi that was $200+ and you need to use the Defi Control Unit II that was ~$100 and i will need two of each so...

You'll be fine, this is a nice engine swap!

JG

just saw this and I will have to follow it!
did you ever consider making it AWD; one engine in front and one in back?
You could have your pick of drive systems I would guess; Eagle, subaru, etc etc

What is your goal; 1/4 mile or autoX?

just a thought

Keep up the posts!

The goal is to build a quick (25 mph to 150 mph)) great handling car for under $15K. It will probably only see one or two 1/4 passes just to say I did it. It's main focus will be twisty back roads and track days.

I considered the AWD idea but it won't allow for the balance/weight/budget I'm shooting for. Maybe that can be a project for the '88 4-cyl in the backyard.

Whats up? pretty cool swap you are doing there, I just noticed im from town too PM sent.
-Roy

------------------
Real Sports cars only have 2 seats....

Matching numbers GT
#17889 of 26,402 made in 1988, 1of 241 yellow GT's

STILL waiting for a reply from diffsonline.com with the measurements of the M3 diff. The rear anti-sway bar will need to be relocated (maybe under the subframe) to allow room for the rear end. Updates soon-hopefully.

Good to see somebody's finally doing it. My brother and I wanted to do this exact project in an '86 Fiero about a year and a half ago, but it never got far past the planning stage. We kept trying to figure out a way to hard-link the transmissions together rather than do anything chain-driven, and ended up shelving the idea, though every now and then it pops back up in "wouldn't it have been cool if" conversations. I hope you can work the kinks out.

The new "stunt driver" attraction at Disney uses a few cars that have multiple motorcycle engines.

all i want to say is AMAZING, simply amazing... i think this is the 3rd thread im adding to my favs...

------------------

https://www.fiero.nl/forum/Forum1/HTML/050262.html "Ritalin"

Well I FINALLY heard back from Dan at diffsonline.com. Apparently he needs to update his used diffs page on his website because he says he doesn't have the 3.15:1 M3 diff for $495 shipped but he can sell me a 3.23:1 M3 diff for $745 shipped.

Looks like I am going to go with a 300ZX TT diff instead. The ratio will be much shorter (3.69:1) so the accelleration will be even better but my top speed will drop to 134mph VS 157mph with the 3.15:1 and the fuel economy along with it. I have seen them go for as low as $60 plus shipping so that is a plus.

It seems that many eager eyes are watching this unique project of yours. If you can get the vehicle to run correctly, there will be many, including myself that will be amazed.

------------------
87GT 3.4 Turbo- 0-60 5.2 seconds -Best
Engine Controls, ECM goodies, Chip
re-programming & odd electronics stuff

I have seen a similar project on tv. On comcast digi. cable. on demand there is a program called 5th gear, they had a Go cart type set up similar to a car, not as heavy though. that had 2 motorcycle engines, you could shift one engine at a time or both together. I will search and come back with my findings.

quote Originally posted by 268 GT: Reverse is not a high priority since this will not be a daily driver but I have thought about it. The current plan is to utilize a high torque starter (diesel truck?) that will mate with a ring gear on the short driveshaft between the left engine and the diff.

Reverse can be done with just that.. a one way bearing clutch (big) and a large DC motor like a starter..

It free-floats when the axles are going forward but when driven in reverse it locks to the shaft and backs the car up..

Its like leaving your std. Fiero in reverse and hitting the starter with the safety switch removed from the pedal.., Long as you can control the voltage its not a problem.. Seen it many times !

Rob

------------------

Rob's (BERKELUSA) 1986'se - 6" inch stretched - Ferarri Vented - Convertible Project (75+ pages)

Don't dis him. It's been done in the past. Franco Sbarro built a car called SuperTwelve back in the 80's.

Can you read French?
La lunette arrière n'a pas de montant, à la manière des Citroën AX. Une fois ouverte, on peut ôter le cache en cuir beige pour laisser apparaitre le bloc moteur : un superbe 12 cylindres en ligne placé en position transversale. La particularité de ce bloc inédit est d'être constitué de deux moteurs de moto 6 cylindres 1300 cm3 d'origine Kawasaki. Chacun a conservé sa boîte manuelle à cinq vitesses : il y a donc deux boîtes actionnées simultanément par un levier commun unique par l'intermédiaire de deux tringleries. Les deux moteurs entraînent chacun une roue arrière et sont simplement reliés par des courroies trapézoïdales qui stabilisent les variations de régime. La voiture peut éventuellement rouler avec un seul moteur en cas de problèmes mécaniques. La puissance s'élève à 240 chevaux pour 800 kg, soit un rapport poids/puissance de 3,3 kg/cheval (4,3 kg/cheval pour une Lamborghini Countach LP500 de la même époque !!). Les accélérations sont donc excellentes avec 5 secondes pour passer de 0 à 100 km/h. Pour cela la vitesse de pointe a été un peu sacrifiée (200 km/h tout de même !).
http://clcalvet.club.fr/sbarro/modelemois/super128-sept2001/super128.html
Now all you need to do is have the quick access like his VW Golf Turbo

Here's another thought: several new big bikes use the starter as a reverse. Yea, the extra weight of the car could put a big strain on the starter but it's a start.

quote Originally posted by netpro55: the dual motor cycle engines were mounted in a car similar to this. I still have not found it, but i will continue searching.

This was brought up on page 1 by MinneGreenGT...

quote Posted by MinneGreenGT: definitely an ambitious & intriguing project - I know there's a company in the UK (Radical Extreme Sports Cars) actually building a small (2.6L?) V8 from two Hayabusa motors... they're intended for use in a spec race car and are expected to run approx 372hp. - also mentioned were a larger 3.0L version expected to produce over 500hp!! Also of interest would probably the the Tiger Z100 (also also UK project) - it's basically a Caterham/Lotus 7 chassis running twin Suzuki (GXSR -1000) engine/gearboxes. But they split the power front & rear (so shifting the gearboxes independently changes the front/rear bias of the power distribution). They also use the mentioned "split T" style shifter. Check 'em out: www.tigerracing.com There are also discussions around the 'net of other cars (notably an Ultima GTR) being built utilizing a twin 'busa setup as well... it's definitely worth looking into (especially to see how others are mating the engines & drivetrains) - Best of luck to 'ya - as it'd be quite a screamer once you get it moving... you'll definitely want to look into a "weight loss" program to bring the car's weight down to a usable level! Keep us posted!