My brother and I picked up a couple rollers and have started our builds. The plan is to put supercharged Hayabusa engines in them, upgrade the suspension and brakes and get them on the road (safely) before working on anything cosmetic.

We picked them up from Keith down in Nepoleon, OH and he recommended I document the build here.

My brother is working now on the fab for the engine cradle and sourcing the transfer case to drive the rear axles. My job at present is to beef up the suspension and brakes to handle the planned 300+HP.

Mine is the black 74 which will probably end up with steel GT flares. My brother's is the primed and glassed out 72.

Let the fun begin!

(If anyone has 5-lug / brake upgrade parts available, please PM me)

This is going to be fun.....imagine all kinds of 914's powered by who's knows what? Don't quote me on this....(in Topanga, Calif. thursday is little friday)...but a few small batteries and a itty bitty tiny electric motor could be really exciting....the way things are going...$4 regular is starting to bug me....
gg

100 ftlb of torque at 8000rpm doesn't sound like fun in a 2000+ lbs car ...

,not even worth going there.

Sounds like a fun build! Looking forward to seeing the progress. I have concerns on in town driveability but I can't imagine it would be any worse than an old bug, but with 5x the top end..

The busa engine is a rocket in something like a Seven but in a 914 with twice the weight I'm more sceptical. Curious but sceptical.

Its what they use on the cars at Disney for the stunts show.. They rip pretty good.

It's all about tractive force, not engine torque. Geared correctly it's a much different picture. In any case, 300 hp @ 10k is 157 ft*lbs of engine torque so not too bad. Hypothetically [to equate to a traditional car engine] with gearing to bring the input engine speed into a conventional transmission back down to normal, you'd be the equivalent of a 314 ft*lb torque at the input shaft. Not too shabby.

Interested to see some progress!

So are you making a shaft adapter to replace the sprocket? Or going with a chain drive differential like you'd see in a formula car. I made a shaft once on a dyno and it worked out pretty nicely.

You guys never cease to amaze me, on both sides of the argument.

I have a project car that is motorcycle powered. It's a tube chassis Nash Metropolitan and I'm using a Honda ST1300 V4.

Just my $0.02:
The only real issue I'm worried about is how the stock motorcycle clutch will hold up to the added wright. I'm targeting 2x the ST1300 weight which gives me ~ 1300 lbs as my target.

In a 914, that Hyabusa engine is going to be asked to deal with somewhere upwards of ~ 3x the weight (Hyabusa weighs about 475 lbs).

I know they get upwards of 450 hp out of the turbo 'Busas so I'm sure there are uprated clutches available. I'd be focused on looking into this as an initial design item.

Best of luck w/the builds and remember: We LOVE, LOVE, LOVE pics!

Have you ever driven a 914 with a high reving engine with comparatively low torque?

I have, and unless you are driving around a race track where you are near the rev limit for 95% of the time, those kinds of engines are the exact *opposite* of "fun to drive".

Bikes weigh less than cars. I hope you get that first. I mean really get it. Some physics education might be helpful. The first time you want to impress your friends and drop the clutch hard.... All of that stuff laying around the street will be your blinging reward.

Forgot - Reverse is always fun with motorcycle powered cars. Here's what I did:
This is a Transworks MiniDif. It's a cut down VW transaxle with all but one forward gear and reverse removed. There's a lever that lets you switch between forward and reverse.

Pics are of my ST engine and then one with an inline 4 motor, like you're running.

So yes, with a motorcycle engine, you get just as many reverse gears as forward!

There are a few other options for reverse but I like this one since it allows for more ways to solve the grearing issues that tend to come when you move from motorcycle sized tires to car sized. At least unless you're running larger diameter tires.

Feel free to PM me, if I can help in any way.
Chris

Chris, I love how you always bring it to another level.

If you can turn down the music, this can be an interesting watch... (you may have to skip a lot to get to the good stuff..)

https://youtu.be/s5Q_rGllPVs

Perhaps one might consider the Honda Gold Wing 1800 engine/trans; has a reverse. While HP numbers are not real impressive, it is a flat 6, so it should sound like a Porsche.
Andys

obviously it'll need a turbo


https://www.engineswapdepot.com/?p=19545&

I'd like to know more about tractive force vs. torque. Possibly we can see this explained in "layman's terms" for us non-engineer's. Maybe a different thread so as to not hi-jack this thread.

obviously it'll need a turbo


https://www.engineswapdepot.com/?p=19545&

Reverse Gearbox for Motorcycle Powered Cars from Roadstercycle

https://thekneeslider.com/reverse-gearbox-f...-roadstercycle/

One of these Hayabusa motors would be a ton of fun!!!

http://www.h1v8.com/maxi-v8---specs.html

Click to view attachment

Interesting. According to one dyno graph I've seen, the torque rating of the 'Busa engine is 50 lb-ft at 2000 RPM. That's not too bad, actually!



--DD

But why aren't you using two hybusas motors for a v8

Then you would have something

This from the guy who always wanted to do a 914 /honda goldwing conversion and was told on this site it was (hands down a dumb f☆☆kn idea)

I love this place

Your the man , beat me to it

go for it.

To me its like making a bunch off engineering issues for little result/advantage,things don't pan out on this one as there is WAY better other repowers .

That is actually a great idea! The motor is shaft drive and it already has a reverse system using the starter.

LOVE the idea!

Build IT! Just build IT!, we can sit here an postulate all day long, Build IT and lets see the outcome.

I have my theories, I also have my theories on a Desiel build. I would also have my theories if you said, Miata, Chevy v6, Ford V8, Chevy V8, LS engine, S2000, Honda K, Honda V6, Nissan V6, Ford /
Yamaha SHO, Corvair, and lets not forgot the Subaru crowd. And now your seeing the idea of Tesla drives.

Build IT, just Build it.

Then drive it like you stole it. If you don't like it you have the skills to drop something else into them, and make a go at it again.

If that happens I have always wanted to build a hybus shifter cart. Can't race it anywhere except in X class, but Damn it would be fun, and a set of rear tires for each run.

I still like the idea of a V8 hybusa, but that is just me thinking about a slightly large lighter cart style car. And Atom V8 clone, Thanks Muller for finding that one.

Those v8 bike based motors are just so compelling from an engineering standpoint - brilliant. Just not sure what you do with them.

As to original poster - Build it man, looks like big fun on a number of plains!!

Well said!

I’ve always wanted to do a hyabusa 914. To handle the weight and help with reliability I was thinking of 2 hyabusas, sitting laterally oppossed with some counter rotating mechanism to get the power to a diff. No matter which way you decide to go, lots of ways to do it, and the one off factor is what it is all about. Good luck.

Maybe a little off topic, but does anyone know if the 901 trans can handle high RPMs?

I know everyone says torque is what kills these transmissions, but can the input shaft spin to 8 or 10k safely? I know with the early RX7's, they limited them to 7k RPM not because of the limit of the engine, but of the transmission. And the transmission would send pieces of shrapnel into the engine bay when they went, so the racecars' solution was a flak jacket around the transmission, hehe.

In any case, I know that 914's were often swapped with rotaries, I'm sure if there was an issue with the trans, someone would know.

Do those links work for anybody? Too many redirects?

This was the Bike Engine Conversion I had always pictured... didnt the original 2L-6 make about that much power anyways? most of the fun with a fraction of the cost of a "correct" -6

The 7 must be a handful. The high rpm scream is something else. What do you think the $ number is on one of those engines?

The build is proceeding slowly. Mostly still stripping the chassis and build a rotisserie to do the needed body work. Going to replace a few pans, reinforce the longs, and modify the front tub for a sway bar, etc. I'll try to post some pictures soon.

Anyone who has a donor body or pieces of one, ping me there are some specific sections I'd like to fix up and patching from another car would save a ton of fabrication work.

Don't forget those cars have been gutted and weight very little.

Update - after much too long. I'll post pictures soon. I was out for 4 months due to illness right after getting the car but I've been back at it recent and working to get the car stripped down to its bare body.

And of course, uncovering TONS of issues along the way and since my brother has been dragging his feet on working on the powertrain idea, I'm stepping back to build up the chassis/suspension first and I'll decide on powertrain later. I must say, however, I'm thinking more along the lines of a 3.0/3.2L Porsche 6 at this point if for no other reason than driveability.

I'll try to get some more pictures up soon and may even start a new thread since it's really a new work in progress.

There's a busa powered 914 for sale here in CA

I built SCCA formula cars with M/C engines and thought about doing the same in a 914.
Dump the 914 transaxle and rear suspension.
Build out a tube frame structure attached at the firewall corners.
Make a box out of 3/8 aluminum plate.
Attach that box to the engine mount throughbolts.
Get a limited slip diff for MC conversions.
Run a-arms from that box to the uprights.
The diff goes inside that box I mentioned.
Slot that box at the diff mounts to move diff for chain tension.

I have pictures of my formula cars if needed. You'll need different rear uprights. A 928 rear uprights can be made to work.

More M/C-powered eye and ear candy...

https://www.youtube.com/watch?v=5LyrsadjpK4

https://bringatrailer.com/listing/1971-honda-n600-6/

As always, ...hope these links work.

Well that was a soundgasam