FJR powered car

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robertwa

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It's been a while since I posted, but thought I would give a quick update. Mounted the radiator (civic aluminum one), and rigged up a paddle shifter on the dash. Got nice aluminum body coilovers for all 4 corners. Next steps are wiring and welding up a header. Anyone got any idea of where to find a single muffler big enough for the FJR? (not silly money). It will be mounted down the passenger side of car so must look nice. What is best for all round power - a 4 into 2 into 1 header, or a 4 into 1?

Paddle shift

wheel_shifter.JPG


Engine and rad

4radiator.JPG


Oh - I am on the lookout for another engine to play with a turbo setup if anyone has one reasonable please let me know

Thanks

Rob

 
I thought someone was making a 4-into-1 for the FJR, or maybe it was wishful thinking on somebody's part. Perhaps someone on the Euro site cold help.

Could you modify the "connector pipes" on the stock exhaust and run 2 connectors into a Flowmaster? How about a couple of "SuperTrapps"? :blink:

 
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Yea, I have seen a 4 into 1 header on ebay. However, no header designed to fit a bike will fit my setup. Looking at the model below, you can see what I have designed - the header will come out the side. My sump will be low enough as it is without pipes underneath! I'm just interested in where to get a large single can. Did any large cc bike come with a single can as standard?

Thanks

Rob

screenshot.JPG


 
I'm just interested in where to get a large single can. Did any large cc bike come with a single can as standard?
Yamaha Warrior comes with a single HUGE single side can, but I think they're a 2 into 1. They should be fairly easy to come by, since it seems that new pipes is the first thing anyone does to a Warrior.

 
Looks like a modern LOTUS 7 or Caterham. How have you set up the drive train?

Regarding Turbo. Wait for a crashed ZX14. 180 plus HP reliably!

 
Forget bike muffs. Try a Flowmaster or Supertrapp. Come in any size to suit, will work and sound great.

 
I like the Supertrapp idea, with adjustable discs. That way you can be as noisy or as quiet as you like and change your mind whenever.

 
Thanks for the suggestions. Maybe a supertrapp is the go, I want it to sound nice, but also want to be able to be within dB limits for auto-crosing.

The car is a replica of the lotus seven or caterham. It will be street legal (pending California DMV approval) and I am aiming for sub 1000 lbs weight without driver. As for reverse - well it won't have one to begin with and I'll see how much of a pain it is. I have seen electric reverses built on these cars using a starter motor, and there are also mechanical boxes you mount inline with the driveshaft, althugh they rob power and are a bit clunky.

I found a driveshaft UJ from an older yamaha on ebay, half of which I mated with half of (the engine side) the UJ from the FJR. It left me with a 4 bolt flange onto which I have bolted a toyota driveshaft, running down to the toyota rear end. Unfortunately the bike output spins opposite to a car, so I have to run my diff upside down to get forward motion. Hopefully it will all stay together.

Here is a quick clip of a R1 engined lotus replica in england. The R1 is a popular choice. I figured the FJR would be better in a car cos it has extra torque

Video clip of R1 engined car

 
Has anyone seen "Lights, Motors, Action" at Disney's MGM Studios. They use 1300 cc engines; I think Yamaha, but not sure if FJR derived. They put them in Opel Corsicas (I think) and do have reverse. I don't think Disney shares much, but maybe they might, if you could get in contact with them. (getting in contact would also probably be not to easy but I thought I would throw out the idea)

 
If power matters you are going to have a little work to do when bringing the pipes out the side. You really want to have the tubes going to the collector(s) be the same length. Most small blocks have available aftermarket snake pit type headers to keep them equal length. This would be the best solution if you can find someone that could fab them for you. Example:

b_headers.jpg


What probably would work best for you is 4/2/1 to help manage the equal lengths. You will also need to try to match the overall header length to the stock system to keep up Volumetric Efficiency, else you will have to modify the intake runner length.

As always, price vs performance will balance the equation.

 
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Turbo application? Check all of the turbos from company's such as Bender that make 'em for Yamaha's four-stroke sleds. The R1 engine is used in sleds as is a variant of the FJR engine. That engine is a triple but with a slightly different bore (I think) and is 1 litre.

John.

 
I found a driveshaft UJ from an older yamaha on ebay, half of which I mated with half of (the engine side) the UJ from the FJR. It left me with a 4 bolt flange onto which I have bolted a toyota driveshaft, running down to the toyota rear end. Unfortunately the bike output spins opposite to a car, so I have to run my diff upside down to get forward motion. Hopefully it will all stay together.
Looks good so far !!

I'm sure you've researched flipping the rear end and the potential for oiling problems?? I know some rear ends can't be flipped, like the Ford 9" without bearing / oiling issues. Gear rotation usually slings oil upward, now it's slinging down ? I seen a few "flips" done on the 4WD boards I've hung out on but never heard of a Toyota being flipped. Just though I'd throw that out there, case in may be a problem.

I also agree with a Supertrapp for ease of noise adjustability and tuning.

 
Highlander,

I agree with you on the flipped axle thing, I spent a long time trying to figure it out. I have mounted the axle upside down, and lookng inside the 3rd member it didn't loko like it would oil properly so I tapped a hole in the oilway above the pinion and am going to use a small electric pump to circulate the oil. It will be similar to what the Nascar guys do when running a diff cooler. It is more for peace of mind rather than anything else. A seized rear end would be no fun. The pump is a small 2gpm flojet self priming pump.

My alternative, which would be way better would be to reverse the oputput of the FJR. I was thinking of moving the driven gear from the middle gear assembly to the left hand side of the picture below - this would switch the direction of the output.

3gear.JPG


Of course I'd have to make up a new shaft and I don't know if there is enough room there for it. Anyone got any ideas?

Does anyone know what the losses are in the system using a rightangle gearbox and shaft drive instead of a chain setup as on other bikes? Early in my plan I was considering ditching the bevel gears and taking a drive straight of the gearbox output shaft instead, with the engine mounted longtitudinally but figured it would be too hard to make a cover with an oil seal. It would have left me with the correct rotation and probably more power...

Rob

 
Typically a right-angle drive with a drive shaft looses ~5-8% more power than a chain drive. Depending on which dyno numbers you use, the FJR looses between 13-16% through the final drive (crank hp vs rear wheel hp). With a chain drive the loss would typically be in the 7% loss range.

 
Been a while since I visited here but progress has been coming along well in the last few months. The car is almost ready for registration, with a hood and windshield left to do. Oh and to mount my front fenders.

CIMG1790.jpg


CIMG1820.jpg


I took it for a 3 mile drive on the street last month during a house move and was very pleased with how well it drove. It took a bit of getting used to the 1" of pedal movement with the clutch pedal!!

 
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