A work of pure genius! - Brilliant "Revetec" Engine

[3yearsharehold]

Orbital don't hold any shares in Revetec , please tell us you didn't give them shares for services years ago for helping with your fuel injection
If they have any interest in rvc it couldn't be classed as independent testing ! You will need to find someone else.
I do hope I am wrong!

[revetec]

Hightower99: You have to really ride the trike to understand the performance and characteristics. At light throttle and low revs we are achieving incredible torque. The best thing is for you to contact GTM trike's Director Shane Subloo and ask him what it was like to drive. He went back after the test and drove his father's 220hp trike to get a fresh benchmark and he said to me on the phone that at 25% throttle we out accelerated it. It's a kind of thing you have to drive to comprehend it. When I drove it for the first time I opened the throttle to 10% it accelerated that hard and I did 1 wheelstand which scared me. I rang Shane and he didn't believe me, so Shane and Gordon flew here to drive it. After their first ride they were blown away at the performance, especially at light throttle and low revs. Again...contact Shane or Gordon at GTM trikes and ask them. They are potential clients and will give an honest evaluation.

I know it's my baby and I'll shout how good it is till the cows come home, but we have had 7 people on the test trike now and they have all been blown away by the performance, especially in the 5-10 throttle acceleration. On the dyno at 10% throttle opening we were producing 125Nm@1,500-2,000rpm.

3yearsharhold: Orbital doesn't have shares in Revetec. Of course the test results wouldn't be independent if they did. Cheers

[hightower99]

Originally Posted by revetec

You have to really ride the trike to understand the performance and characteristics. At light throttle and low revs we are achieving incredible torque.

Unfortunately I don't think I will be able to come down to Australia and try one out in the near future (although I have always wanted to go to Australia )

Originally Posted by revetec

The best thing is for you to contact GTM trike's Director Shane Subloo and ask him what it was like to drive.

I guess I will have to see if he can give me some actual numbers and not just subjective feelings...?

Originally Posted by revetec

He went back after the test and drove his father's 220hp trike to get a fresh benchmark and he said to me on the phone that at 25% throttle we out accelerated it.

You need to be alittle more specific here. Your engine makes less than 95HP at WOT so it is generating alot less power at 25% throttle (which I am assuming is % of WOT angle and not just throttle handle position?). There is alot of missing info like: what speeds are you measureing the acceleration from and to? (i.e. 0-100km/h? 80-120km/h?) How exactly was it determined that one "accelerated" faster than the other? That statement could be interpreted to mean that the revetec powered trike can out accelerate a 220HP trike by only using 25% throttle angle... (which is patently ridiculous as your engine makes <95HP at WOT). I think that maybe the revetec gives a harder initial kick in the pants even at low RPM compared to the 220HP trike (which will need to rev higher and dump the clutch to give as much of a kick), but 220HP>95HP so you can't win.

Originally Posted by revetec

On the dyno at 10% throttle opening we were producing 125Nm@1,500-2,000rpm.

Do you really think I am going to believe that? That means your engine should be easily able to pump out 700Nm+ (which it doesn't). How can that possibly be true? 10% doesn't open the airway much at all so if you are making 125Nm at 10% you should be making alot more than 202Nm at WOT.

[revetec]

Our engine doesn't apply torque in the same manor than a conventional engine. You have to change your thinking here. Having such high torque at low revs and throttle response is a direct link to higher mechanical transfer earlier in the stroke. This is why the performance experienced on testing the engine on the day was so impressive. Light throttle, low revs, high torque, harder acceleration equals less fuel usage. On the road, Shane was throttling around 5-10% which was all that was needed to provide a good acceleration. At 1,500rpm and 10% throttle, because the revs are low, the volumetric efficiency is high due to the low revs. At 3,000rpm the throttle opening needs to be about double to breathe the same amount of volumetric efficiency, but of course, power is increased. Why this is a significant gain is that we transfer the torque with greater efficiency when an early peak pressure occurs, such as low RPM. This provides better acceleration in the lower rev range. We definitely experienced the effect of this during our first test day. Minimal throttle response was need to accelerate away from a standing start. A normal take off uses about 5% throttle. Check out the video "Driving in traffic 2" and you will see Shane wrist throttle on from a standing start. He said he consciously had to remember to throttle less than normally.

Our engine has a very unique characteristic which I hope one day, everyone can have the experience of driving it.

If you email me on brad@revetec.com I can give you Shane's contact details and you can ask him yourself how the engine performs and its driving characteristics. You can also talk to him on Skype.

[hightower99]

Originally Posted by revetec

Our engine doesn't apply torque in the same manor than a conventional engine. You have to change your thinking here.

How so? Is it not still a reciprocating piston surface in a cylinder that is being turned into rotary motion? Yes you have a novel way of making the transistion from reciprocating to rotary motion but the begining and end is still the same. I understand the characteristics of your design (it has longer lever length closer to TDC thus taking advantage of higher cylinder pressure and keeps a longer lever length over the whole stroke [at the expence of angular velocity]).

Originally Posted by revetec

Having such high torque at low revs and throttle response is a direct link to higher mechanical transfer earlier in the stroke. This is why the performance experienced on testing the engine on the day was so impressive.

I know you know how a throttle works. if your engine is generating 125Nm at 10% throttle it should be making way more than 500Nm at WOT. Unless of course that your engine is capable of max VE (not 100% but the maximum achieved) at low throttle angle. Maybe you have a mismatched throttle? That is one of the few explainations that would explain why you can make 125Nm at 10% but only 202Nm at WOT. I would make a quick guess that you can achieve maximum VE at only 25%-30%, which means what you think is 10% throttle is actually 33%-40% throttle.

Originally Posted by revetec

Light throttle, low revs, high torque, harder acceleration equals less fuel usage.

You actually want the throttle open as much as possible to achieve the greatest efficiency... But yes that would definitely mean less fuel compared to a conventional crank engine.

Originally Posted by revetec

at 1,500rpm and 10% throttle, because the revs are low, the volumetric efficiency is high due to the low revs. At 3,000rpm the throttle opening needs to be about double to breathe the same amount of volumetric efficiency, but of course, power is increased.

The VE should not be high at 10% throttle! It should be roughly an 8th to a 10th of what is achieved at WOT. Also low RPM should not be very good for VE for an engine that is trying to fill such oversquare cylinders (wide bore, very short stroke) combined with only breathing through a single intake valve, and no form of resonant supercharging optimisation. I can't remember but what is the timing between the output shaft and the pistons? is it like a conventional crank system (i.e. 1 revolution allows 2 strokes of the piston).

Originally Posted by revetec

Minimal throttle response was need to accelerate away from a standing start. A normal take off uses about 5% throttle.

I can take off in any normal car at idle... I can even change up a gear or two. Anyways I understand your point. I believe that you need less throttle to perform a normal start however I refuse to believe that a <95HP engine is able to out accelerate a 220HP engined vehicle when they are otherwise almost identicle. You are going to have to show actual numbers to convince me of that.

Originally Posted by revetec

Our engine has a very unique characteristic which I hope one day, everyone can have the experience of driving it.

To be honest I would love to drive something that is revetec powered just to feel what it is like and do some testing on it. But I also want to build my own engine and get that running

I sent you an email hopefully my email address doesn't get it sent to your junk box....

[Matra et Alpine]

ht, perhaps you woudl do best to understand how different engine types affect performance before questioning Brad so much when he's busy

For example .... Ducati Twin ( and the Honda SP-1 ) out accelerated their competition on the track despite being "equivalent power". Would perhaps allow you some insight into other possibilities existing beyond the bookwork.

[clutch-monkey]

heh, i want a go on that trike
...any chance on fitting one of those engines in a mini clubman..?

[revetec]

Check out this video of the X4v2 engine - Trike Wheelie and Powering On at 25% throttle

[CHOOK]

Originally Posted by revetec

Check out this video of the X4v2 engine - Trike Wheelie and Powering On at 25% throttle

Hi Brad - congratulations on this milestone. It all looks and sounds great.

Can you enlighten us on what Orbital will be doing exactly once they get the engine?
Will they be applying their technology on top of the Revetec engine before doing any testing as I am sure both companies technologies together would throw out some mind boggling figures. Have they provided a timeline as to when they will finalise the testing and expected details made public? Does the Government grant come with a deadline to have a final product?

Cheers

[revetec]

Thanks for the congrats. First step is independent certified testing. We will release the figures as soon as we have them.

Cheers
Brad

[hightower99]

Originally Posted by Matra et Alpine

For example .... Ducati Twin ( and the Honda SP-1 ) out accelerated their competition on the track despite being "equivalent power". Would perhaps allow you some insight into other possibilities existing beyond the bookwork.

That has more to do with there ability to smoothly power on through corners allowing the drivers to basically achieve longer "straights" (They could start accelerating sooner and therefore had the advantage going down the straights). It also has to do with the actual power curve the engines made. Whereas they could have "equivalent power" that is only taking peak power under consideration, they probably make more average power over the range used during in gear acceleration (i.e. if you redline at 10000RPM and drop down to 8500RPM when you shift up then the "in gear" rev range is from 8500RPM-10000RPM for the gear you changed up to [assuming you stay in it to redline]) . The point being that they could either apply the power for a longer period of time, or they had more average power.

This does not get close to explaining how a <95HP engined trike is capable of out accelerating a 220HP engined trike, in a straight line, from a standing start, with the <95HP engined trike only needing 25% throttle!

I think they are just being wowed by the large amount of torque at low revs which gives a bigger initial kick in the pants, but that doesn't mean that it will actually accelerate faster.

I just thought about something:

What transmission ratios are they using with the revetec powered trike (in relation to the 220HP trike)?

If they are using the same ratios then the revetec should be at a serious disadvantage when it comes to in gear speed and top speed (as it only goes up to 3000RPM). I would bet that if they actually timed any sort of acceleration runs they would find that the revetec is significantly slower because it would have to change up more often.

[Matra et Alpine]

ht, what you just explained in 6 paras is precilsy all the reasons WHY the DUc's pulled away in corners .. the torque was delivered in a more "usable fashion" and hence deliverd the necessary traction.

[hightower99]

Originally Posted by Matra et Alpine

ht, what you just explained in 6 paras is precilsy all the reasons WHY the DUc's pulled away in corners .. the torque was delivered in a more "usable fashion" and hence deliverd the necessary traction.

Actually I said that in the very first sentence

But how does that apply to a <95HP engined trike accelerating faster than a 220HP engined trike in a straight line from a standing start at only 25% throttle?

Do you not agree that that sounds highly unlikely?

[Matra et Alpine]

Originally Posted by hightower99

Actually I said that in the very first sentence

Based on having to have it pointed out to think about it in a much earlier post

But how does that apply to a <95HP engined trike accelerating faster than a 220HP engined trike in a straight line from a standing start at only 25% throttle?

Do you not agree that that sounds highly unlikely?

There are many possibilities true, including the psychometrics of expectation

But as you DID come around to realise the difference a V twin power delivery made over an I4 then is it just possible that the Revetec may do something similar ? After all you dont' have evidence to the contrary -- yet

[hightower99]

Originally Posted by Matra et Alpine

Based on having to have it pointed out to think about it in a much earlier post

Come on, you didn't teach anything you quickly mentioned that I should think about the different characteristics of different engines. I think that I posted an adequet response that showed that I know exactly what you are talking about and that I questioned how that should apply to this problem.

Originally Posted by Matra

There are many possibilities true, including the psychometrics of expectation

Well I think the psychometrics (never heard that word before I assume it means the mental expectations coupled with the sensory input?) has more to do with the percieved performance than what is actually happening.

Originally Posted by Matra

But as you DID come around to realise the difference a V twin power delivery made over an I4 then is it just possible that the Revetec may do something similar ? After all you dont' have evidence to the contrary -- yet

What do you mean "come around" did I not show that I knew what you where talking about even though you didn't explain???

Anyways the difference between the <95HP revetec engine and the 220HP engined trike are much greater than between "similarly powered" V-twins and I4s.

The stated info says that the revetec engine (that makes less than 95HP at WOT) is able to out-accelerate a 220HP engined trike just by using 25% throttle...

220HP>>>>95HP the revetec engined trike cannot accelerate harder and certainly not when using only 25% throttle.

Can it give a big initial kick in the bum and do wheelies? Certainly! No question about that, they have video evidence and I wouldn't question that for a second (it isn't surprising either as the revetec is a larger displacement engine which is designed for greater torque at low RPM).

Can it out-accelerate a 220HP trike? Not even close to a snowball's chance down under!