FS-DE and a 10,000 red line... How?

[Yello-MP3]

I have been reading alot and i am wondering how it could be done. I know to start we need to go through the whole drive train and pretty much any moving part has to be replaced with very light replacements. Starting with rods and pistons would probably need to be atleast aluminum if not titanium or some carbon type composite metel. I think we would need to have dual valve springs and retainers with very stiff springs. Next would be either a shaved, knife edged, or even totally knew crank shaft... also being aluminum or titanium. Next would be the cam shafts themselves and furthermore the valves also be aluminum or titanium..... Thats a start, what else would we need?
Thanks in advance and i think this will prove to be a very informative thread
Peace,
Zane
( In search of a high reving beast )

 

[Dimitrios]

Well, almost anything is possible with enough time/money.

You also need to bring up the issue of providing enough spark and fuel at 10-grand.....

But my primary question is: why would you want to wind up to 10k in the first place?

 

[blynzoo]

Look at the power curve of the FS-DE on a dyno. By the time you get to about 6200 the #'s start to fall. At 10K, without boost, you would just be thrashing your motor without any significant gains. Sure, you could do the 1/4 mile in 2nd gear, but other than that....

Honda has designed the S2000 motor (and fuel and timing) to not just meet the requirements of 10k, but to benefit from it (although the '04 version has a lower redline and is much more streetable). FS-DE's powerbands do not match a 10k redline.

Just a thought, best of luck to you.

 

[Yello-MP3]

hey

Thanks for the replys. No the only reason the fs-de engine falls is because just that, the lack of fuel and timing and the major reason being the ecu letting up for safty matters. Any engine no matter what company it happens to be made by can be made to rev out and have large gains from it. Of cousre the differnces are the size of the engines and therefore balance of such. If correct fuel and timing were assessed the fs-de engine could be very strong from mid rpms all the way up and further more proper tuning could get you a pretty stought set up from lower rpms all the way to redline. Just a btw i am not speaking of a NA set up this is for a turbo application. Hit me back with anything else and we need more folks input on this subject.
Peace,
Zane

 

[jred321]

talk to tri point or one of the shops that has a full drag protege, see what they have to say

you're going to need to do some heavy head and manifold work too to make sure everything flows enough

 

[njaremka]

also take alook at piston speeds. I haven't done the calculations, but they gotta be HUGE at that rpm.

 

[122 Vega]

The single biggest problem you will run into is oil pump cavitation. direct crank driven oil pumps are prone to cavitation. I have a Cosworth Vega motor in my race car that will turn 10,000, but the power does not come on until about 5800. you only have one cam profile to work with. The VTECs can spin higher because of the changing cam profile.

You could build the motor to do it, but the question is why?

Britt

Add: You would have to drysump the oil system. You really could not drive this car on the street. The cams would limit torque so much at low rpms you couldn't drive it confortably. The price to build this engine would far outweigh the results. look at $10-12,000 to build this reliably. remember that most race engines are torn down every few runs. I tear mine down every 15 hours of use, and most people tear them down at 2 hours of use.

 

[jaymode]

basically you want to turn a mazda motor with torque into a honda motor without torque that has lots of horsepower high in the rpms? I dunno if it was me I would rather have a lower redline with a engine that has better torque and a more linear powerband.

 

[twilightprotege]

the problem is the much larger crank size compaired to the piston size.

if you want that rpm move down to atleast the 1.8L crank or even lower

anyway, you wont make any more power. power is limited to the piston size. there are no if's or but's about it. the easiest way to think about it is if you have an engine, dont change anything but the crank size and stroke the engine, it will create the same power just at a lower rpm. if you de-stroke an engine it will create the same power just at a higher rpm.

 

[Installshield 2]

The VTECs can spin higher because of the changing cam profile.

This is a common misconseption...Honda's VTEC system has very little to do with the engine's ability to rev higher "physically"...The larger cams allow the breathing needed, but that is irrelevant...The purpose of the system is to allow the small displacement engine to have the cam profiles needed for street drivin lowend torque...The engine very well could spin that high without the system, but if it had only the big cam profiles, it would virtually be undrivable on the street...But the design and balance of the engine's internal layout is what allows the high revs...If you could bolt a B18C5 VTEC head on an FS block, you still couldn't rev to 8700rpm...

You are correct though that oiling would become a major issue with these high of speeds...My bet goes towards the piston speeds though for 10,000rpm...The long stroke and low rod ratio will create such huge piston speeds that entire recpricating assembly would do a backflip out of the block, no matter what internals you used...Maybe you could do it with the stock specs, but at most for no more than 10 runs...

So you would have to basically change out the entire internal layout...and bring in more rev happy specs for the parts...Weight actually wouldn't have as much to do with how fast the engine could physically spin...but it would effect total output...and "usually" heavier internals tend to have less flectures and tolerate higher speeds better than lightweight internals...mega expensive exotic lightwieght internals, such as those used in some F1 engines would be best...But probably you would be able to get a new BMW M3 before you could afford 4 con rods made of these materials...

it very well could be done...But the engine would be so far from stock, it could hardly be referred to as an FS at all...The block is up in the air to me, it probably would tolerate it...But i don't know much about the crank mounting journals, or strength of supporting areas in relation to the crank...

Someone mentioned...It very well would be easier to get a FP to rev that high, if you had to use the stock specs...the lower stroke and higher rod ratios would tolerate it better...But by sourcing the right parts it could be done...Tripoint and Sunbelt are running something like 8800 rpm from what I remember....and through the SCCA rules they are forced to have almost stock specs as far as crank diameters and rod length...But about $17,000 worth of parts and labor goes into each one of those engines...

 

[Installshield 2]

the problem is the much larger crank size compaired to the piston size.

if you want that rpm move down to atleast the 1.8L crank or even lower

anyway, you wont make any more power. power is limited to the piston size. there are no if's or but's about it. the easiest way to think about it is if you have an engine, dont change anything but the crank size and stroke the engine, it will create the same power just at a lower rpm. if you de-stroke an engine it will create the same power just at a higher rpm.

Andy the "stroker" theory mostly only applies to the FS and FP...A lot of stroked engines will flat out create more power overall, at a higher peak hp, and more lowend torque than any of their "destroked" counterparts...That isn't the case though with the FS and FP...

But if you stroke an engine, but decrease its bore...and do not overall increase displacement...Your theory is fairly accurate...

But the power being related to piston size confuses me...Power is related to revs very closely...If you get the same sized piston to move faster, and have adequate breathing and tuning changes to handle the increased revs...You will always make more power...If you do all the stuff to physically get the FS to sping that high, but keep the stock cams and stock ECU (except get rid of the rev limiter)...the engine would just stall...It couldn't pull anywhere near enough air to handle those speeds...

 

[122 Vega]

quote:
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Originally posted by 122 Vega
The VTECs can spin higher because of the changing cam profile.

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



This is a common misconseption...Honda's VTEC system has very little to do with the engine's ability to rev higher "physically"...The larger cams allow the breathing needed, but that is irrelevant...The purpose of the system is to allow the small displacement engine to have the cam profiles needed for street drivin lowend torque...The engine very well could spin that high without the system, but if it had only the big cam profiles, it would virtually be undrivable on the street...But the design and balance of the engine's internal layout is what allows the high revs...If you could bolt a B18C5 VTEC head on an FS block, you still couldn't rev to 8700rpm...

I was misunderstood. What I mean is not that the cam profile somehow physically is the reason the engine spins higher. What I mean is a basic fluid dynamics issue. Without air/fuel/volumetric efficiency at a given rpm, the motor will cease to accelerate and maintain a given rpm. The main thing that allows a motor to spin at a higher rpm is the availability of air/fuel and ignition. Any motor will continue to accelerate until it's internal physical destruction when given the proper air/fuel. Granted, the VTEC motors may be more durable, but just because you build a durible motor does not mean that it will go 10k.
Pretend you can take a VTEC head and put it on a FS and it will spin to the 8k redline or whatever the VTECs do now, provided that it does not have a mechanical failure (spun rod bearings are the most likely culprit with the size of the FS rods).
Like I said before, my race motor turns 10k if I want it to, but it makes no torque below about 4000. If I had the ability to put a VTEC type valvetrain on it, it would then produce the torque down low due to the increase in VE in a given rpm.
Let's pretend again that you have a VTEC motor and you disable the high rpm cam profile. This motor will not then turn high rpm. It simply cannot flow enough air to allow high rpm operation. This is what I am saying. The FS motor cannot turn high rpm due to its production type cam grind.
I agree that "if" you could flow enough air for the FS to reach 10k, you would then have to consider longevity of the internals. I have seen spun rod breaings, thrown rods out the block (break at the wrist pin), broken valve train components and actual block failure issues (horizontal seperation). I have also sheared off the back of a crank with the flywheel and clutch assy attatched.

More later, I'm at work...

Britt

 

[bjdesire]

isnt this all kinda like the rotary engines mazda makes, they are hi reving, but they make almost no tourque at low rpms, and they need to be driven at high rpms. although rotary was designed for this, and i dont think regular piston engines were because it will just destroy them.

 

[twilightprotege]

install - yeah the reason i say piston size is directly related to power is a bit hard to explain, but i'll try... it is all to do with the amount of air the combustion chamber can hold. these are just figures i've made up...

at 8000rpm, our engine will pump out 1000cc per cylinder (8000/4 cylinders*0.5L) for an engine will less stroke (say the 1.8L) to get the same amount of cc per cylinder you have an equation of
1000cc * 4 cylinders / 0.4L = 10000rpm.

so since power is a direct relation of air and fuel, with all else being equal it is also a relation ot piston size and stroke.

does that make sense?

 

[Stealth5]

yeah, to make revving it that high effective, youd have to totally re-engineer and retune the motor

 

[Stealth5]

install - yeah the reason i say piston size is directly related to power is a bit hard to explain, but i'll try... it is all to do with the amount of air the combustion chamber can hold. these are just figures i've made up...

at 8000rpm, our engine will pump out 1000cc per cylinder (8000/4 cylinders*0.5L) for an engine will less stroke (say the 1.8L) to get the same amount of cc per cylinder you have an equation of
1000cc * 4 cylinders / 0.4L = 10000rpm.

so since power is a direct relation of air and fuel, with all else being equal it is also a relation ot piston size and stroke.

does that make sense?

no replacement for displacement

 

[Installshield 2]

quote:
--------------------------------------------------------------------------------


I was misunderstood. What I mean is not that the cam profile somehow physically is the reason the engine spins higher. What I mean is a basic fluid dynamics issue. Without air/fuel/volumetric efficiency at a given rpm, the motor will cease to accelerate and maintain a given rpm. The main thing that allows a motor to spin at a higher rpm is the availability of air/fuel and ignition. Any motor will continue to accelerate until it's internal physical destruction when given the proper air/fuel. Granted, the VTEC motors may be more durable, but just because you build a durible motor does not mean that it will go 10k.
Pretend you can take a VTEC head and put it on a FS and it will spin to the 8k redline or whatever the VTECs do now, provided that it does not have a mechanical failure (spun rod bearings are the most likely culprit with the size of the FS rods).
Like I said before, my race motor turns 10k if I want it to, but it makes no torque below about 4000. If I had the ability to put a VTEC type valvetrain on it, it would then produce the torque down low due to the increase in VE in a given rpm.
Let's pretend again that you have a VTEC motor and you disable the high rpm cam profile. This motor will not then turn high rpm. It simply cannot flow enough air to allow high rpm operation. This is what I am saying. The FS motor cannot turn high rpm due to its production type cam grind.
I agree that "if" you could flow enough air for the FS to reach 10k, you would then have to consider longevity of the internals. I have seen spun rod breaings, thrown rods out the block (break at the wrist pin), broken valve train components and actual block failure issues (horizontal seperation). I have also sheared off the back of a crank with the flywheel and clutch assy attatched.

More later, I'm at work...

Britt

Very good points...and I did misunderstand your first post...I just assumed you meant the ability to physically spin that high...and nothing related to making power that high through terms of breathing and tuning...

But yeah, what I mean is that you can do whatever you have to to get the engine to breath at that high of an rpm...But it will not hold together at that high of rpm...It physically will not handle the stress of that high of operation with stock spec'd pieces...