After seeing a headline today regarding a rather special 4age, I'm curious what engines could be candidates for 5-digit rpm ranges. Let's say the parameters are:
1-production based, not some special race application
2-US market, not necessarily current.
3-availability of donors, aftermarket support.
4-Pistons!
What do y'all think?
Does it have to be from a car? My challenge car meets those requirements and does 16,500 rpm... ;)
It's (4) that's the problem .
A lot of motorcycle engines should qualify if you really wanted pistons,
How many seconds does it have to last?
Ford 4-cam is about the closest in current production. The flat-plane one does what, 8500?
MotoIQ just did a build series on building a 10k RPM K series motor 3 weeks ago.
DSport built a 10k Honda B series engine a decade ago.
https://dsportmag.com/the-cars/project/engine-tech-1000-whp-honda-b-series-build-part-2/
I hear you can get the Toyota 2zz-ge to 10k as well. But I don't have a reference for that one.
Both Honda motors are very well supported. The Toyota/Yamaha 2zz is semi-well supported, but parts are significantly less plentiful for a project like that.
The obvious ones are the Hondas (K, B, etc). People build drag race versions of those that do 10K.
I've heard of 10K RPM S54s, and the same probably exists for other engines that are over 8K stock although most of those are pretty expensive (Porsches, Ferraris, etc).
G10 from the lowly Geo Metro
G13 Swift GT engine
I don't believe claims of a built 10k engine until it's actually been used hard for the expected lifespan. The loads on the rods go up exponentially with engine speed, so 10k is a lot harder than 8k.
I've built an 8000 rpm 2.0 Miata engine. After 6k miles of very hard use (mostly track with some rally), we tore it down and found some very worn rod bearings. It did the job though.
The little Honda S600 roadster from the 60s maybe? Lexus LFA V10? Numerous liter bike engines, rotaries with ceramic apex seals, though you said pistons only *takes my ball and goes home.*
I think with most mass produced passenger car engines, even if your rotating assembly and valvetrain are up to the task of 10k, the water and oil pumps are likely to fail if you're sustaining that kind of rpm for more than a few moments. I'm told the 5.0 Coyote mustangs are good for at least 8k if you replace the factory oil pump, apparently they'll come apart if you're unlucky.
Keith Tanner said:
I've built an 8000 rpm 2.0 Miata engine. After 6k miles of very hard use (mostly track with some rally), we tore it down and found some very worn rod bearings. It did the job though.
That's about what I see for track use on my S54. I replace rod bearings after 100 track hours, and with an average speed of about 70 mph on track... :)
See, y'all are talking sense when what I was hoping for was a bunch of questionable recipes for potentially sending eBay pistons into orbit.
Bike engine in car is cool, but something about the recipe doesn't fill me with enthusiasm for a street vehicle. Of course this is all still very hypothetical. Most of the catalogs list cams that get up to 8k-ish so that seems like a more realistic expectation. So then it becomes, what is the cheapest way to have a fun car for street use that could see a modified rpm range for no other reason than laughs. I wonder about the longevity of a duratec 2.0, possibly with an extra atmosphere jammed up in it. Or two.
The best thing about bike engined cars is they also have sequential transmissions. They're very much not carlike but feel/sound like a formula car. But I'd hate to drive one on the street.
In reply to Keith Tanner :
What if the expected lifespan is one run?
In reply to Keith Tanner :
Also, street car needs reverse.
In reply to Appleseed :
Lifespan needs to be on the usable side. Not necessarily 50000 miles, but a couple years of hooning on weekends maybe?
In reply to dannyp84 :
S600/N600 does not rev. They look like bike motors, but aren't.
Getting a transmission to shift at that RPM is likely harder than getting the motor to spin that fast. I only say that because it sounds so much fun, but years of playing games in my head and I still don't have a transmission answer. Even in bike powered cars, the transmissions wear out much faster than the rest, and they aren't generally shifting with the input much over 8.5k, if even that high.
In reply to matthewmcl :
Sure. Throw more water on the fire.
Jk. Simply something I hadn't considered but realize is probably a reason this isn't a more common endeavor.
I wonder what a built 2zz could do in a xB... just idle curiosity.
In reply to matthewmcl :
do you mean cars running a bike engine into a normal car transmission? In my F600 i generally shift between 14-15k, and I don't have to touch the clutch after I get it moving :)
I've shown this before - if my wife leaves this world before I do I'm selling it all and giving OS Giken and Rebello Engines a large blank check to get this rolling my way.
I can easily live on beans and rice and the kids won't have to worry about some wicked step mother taking their inheritance because it'll all be spent on parts and high octane fuel. Surprise, surprise as the lady sings.
Appleseed said:
In reply to Keith Tanner :
What if the expected lifespan is one run?
That's why I did not specify a specific lifespan :)
Tom1200
PowerDork
1/2/24 11:21 p.m.
So the Datsun A-series engines will just do 10k.
They will do 9300 rpm on the stock bottom end.
I keep mine to 8600 becuase after that the rings start wearing quickly. At 10k you are going to get 4hrs out of the motor.
If one only occasionally reved above 9K you could probably get 5000 miles out of it.
LSx with a 4 cylinder tachometer. It'll show 10k+ on the dial, be fast and last a long time. LOL
In reply to tester (Forum Supporter) :
The ignition pulses on an LS already look like a 4 to a tach :)