Single cylinder engines

[nvpF1crazy]

I was going through the FSAE West event handbook and results and noticed that quite a few of the top running teams have used single cylinder Yamaha WR450F and Honda CRF450X engines. Apart from the weight reduction and packaging advantages, don't the cars feel less power?

Also do any issues come up in turbocharging single cylinder engines?

[nvpF1crazy]

I was going through the FSAE West event handbook and results and noticed that quite a few of the top running teams have used single cylinder Yamaha WR450F and Honda CRF450X engines. Apart from the weight reduction and packaging advantages, don't the cars feel less power?

Also do any issues come up in turbocharging single cylinder engines?

[nvpF1crazy]

Especially after the 20mm restrictor.

[Big Bird]

Yes, they do have less power. The question you have to answer is, how important is power?

[nvpF1crazy]

I think except for endurance, there are no real opportunities to use all the 100+hp on the 600cc engines. Plus where I live there is no market for these bikes so getting an engine, spare parts, service, etc. is difficult and costly.

I wonder if there are any 4 stroke Briggs and Stratton engines in FSAE. Or maybe a Honda CBR250R or Ninja 250. Will help a lot in fuel economy and the latter 2 engines even have a wider torque range.

[Hector]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by nvpF1crazy:
I think except for endurance, there are no real opportunities to use all the 100+hp on the 600cc engines. </div></BLOCKQUOTE>

After the mandatory 20 mm restrictor, no one is making 100+ HP.

Our 600 cc car showed around 65 HP on the dyno at comp a couple years ago. We spent only 20% of our time power limited during endurance. Take what you want from that.

[Mbirt]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by nvpF1crazy:
I wonder if there are any 4 stroke Briggs and Stratton engines in FSAE. Or maybe a Honda CBR250R or Ninja 250. Will help a lot in fuel economy and the latter 2 engines even have a wider torque range. </div></BLOCKQUOTE>UM Dearborn and UB have both run v-twin B&S motors coupled to a CVT and placed well with the setup. You have to reduce the displacement of the v-twin to get it under 610cc. The (single-cylinder) CBR250R is too new, but might be a good option for Indian teams to get their hands on something higher-tech than what is usually available to them. The Ninja/EX-250 is prohibitively heavy for the power it makes.

Not a whole lot has changed since this thread, except for the addition of several more teams to the list to have excelled with singles after RMIT and Delft:http://fsae.com/eve/forums/a/t...48/m/94810786121/p/6 (http://fsae.com/eve/forums/a/tpc/f/125607348/m/94810786121/p/6)

ETS won accel at FSAE California 2011 and claimed 58 hp from the WR450 motor in their 335 lb. car. Bob Paasch has gone on record stating that GFR's "endurance tune" is good for 42 hp. An n/a single can be developed to make more power than the less-developed 4-cylinder packages and blown singles have made 85+ hp. But, to echo Geoff's remarks, was the team with the 85 hp turbo single faster than the 58 or 42 hp n/a singles?

[Bcohen5055]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Hector:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by nvpF1crazy:
I think except for endurance, there are no real opportunities to use all the 100+hp on the 600cc engines. </div></BLOCKQUOTE>

After the mandatory 20 mm restrictor, no one is making 100+ HP.

Our 600 cc car showed around 65 HP on the dyno at comp a couple years ago. We spent only 20% of our time power limited during endurance. Take what you want from that. </div></BLOCKQUOTE>

Someone is
http://www.youtube.com/watch?v...youtube_gdata_player (http://www.youtube.com/watch?v=KxiGZyzIJJY&feature=youtube_gdata_player)

[Ben K]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by nvpF1crazy:
I think except for endurance, there are no real opportunities to use all the 100+hp on the 600cc engines. Plus where I live there is no market for these bikes so getting an engine, spare parts, service, etc. is difficult and costly.

I wonder if there are any 4 stroke Briggs and Stratton engines in FSAE. Or maybe a Honda CBR250R or Ninja 250. Will help a lot in fuel economy and the latter 2 engines even have a wider torque range. </div></BLOCKQUOTE>

I think UTA ran a 250 with a turbo a few years back. It sounded like a blender having a heart attack. Also known as awesome.

Ben

[wagemd]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Ben Kolodner:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by nvpF1crazy:
I think except for endurance, there are no real opportunities to use all the 100+hp on the 600cc engines. Plus where I live there is no market for these bikes so getting an engine, spare parts, service, etc. is difficult and costly.

I wonder if there are any 4 stroke Briggs and Stratton engines in FSAE. Or maybe a Honda CBR250R or Ninja 250. Will help a lot in fuel economy and the latter 2 engines even have a wider torque range. </div></BLOCKQUOTE>

I think UTA ran a 250 with a turbo a few years back. It sounded like a blender having a heart attack. Also known as awesome.

Ben </div></BLOCKQUOTE>

UC Irvine ran some sort of supercharged Briggs V-Twin (from a generator if I remember correctly) at West two years ago and it was probably one of the best sounding FSAE cars I've ever heard. I kept swearing there was a straight pipe Ducati running around in the paddocks...

[Pete Marsh]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> Someone is
http://www.youtube.com/watch?v...youtube_gdata_player </div></BLOCKQUOTE>


What's with this output being so high? Is this with a correction to show engine power?
The highest output I ever saw on the MIS dyno was 86hp. (Cornell turbo).

Pete

[Spetsnazos]

Our current team says they can't do well without forced induction. I lol'd hard and just moved on.

[nvpF1crazy]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Mbirt:
The (single-cylinder) CBR250R is too new, but might be a good option for Indian teams to get their hands on something higher-tech than what is usually available to them. The Ninja/EX-250 is prohibitively heavy for the power it makes.
</div></BLOCKQUOTE>

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Hector:
Our 600 cc car showed around 65 HP on the dyno at comp a couple years ago. </div></BLOCKQUOTE>

Going by Hector, will the 250cc engines have enough peak power left after the restritor?
I looked up the CBR250R engine and its fantastic. Host of innovations for a single and a wide torque band. But for FSAE I don't know.

[Demon Of Speed]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by nvpF1crazy:
Going by Hector, will the 250cc engines have enough peak power left after the restritor?
I looked up the CBR250R engine and its fantastic. Host of innovations for a single and a wide torque band. But for FSAE I don't know. </div></BLOCKQUOTE>

An engine guy please fill in more here/correct what I have wrong.

The 600cc engine are air restricted to around 11000 rpm, the 450cc are air restricted to 14000 rpm, and the 250cc are air restricted to like 22000 rpm (someone please check my memory here). The point is that the smaller engines are not really air restricted per say. The single cylinder engines have a higher variance in restricter velocity, which is why you will see the with larger plenum volumes per displacement that multi-cylinder engines to help reduce this fact. In fact we found our 19mm 'ethanol' restricter had no differance from the 20mm restrictor on our 450cc engine.

[Bcohen5055]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Pete Marsh:

What's with this output being so high? Is this with a correction to show engine power?
The highest output I ever saw on the MIS dyno was 86hp. (Cornell turbo).

Pete </div></BLOCKQUOTE>

It's uncorrected 108 at the wheels, I'll try to post the dyno plot tomorrow if I have a chance

[Kirk Feldkamp]

There are two different CBR250R engine configurations now, so be careful which one you're referencing. The older ones had a double-o-bad 4 cylinder that revved to 19000rpm and had lots of tiny little internals. This is what the UTA cars used. The new bike looks cooler, but has a single. Arguably cool too, but not nearly as cool as the older models.

Whatever you decide to choose for your first engine, it's actually much more important that your engine is easy for your drivers to use, and doesn't have any major tuning/starting issues. It matters *much* more that your drivers actually get to practice in the car a bunch before they're asked to compete. This approach will net you a lot more points at comp than worrying about which engine is "the best" for you right now. Get something made in the last 10 years that won't break the bank, and get it running as quickly as possible.

-Kirk

[TMichaels]

We had a dyno in 2008 at FSG.
The results can be found here:
http://www.formulastudent.de/f...G08_Dyno_Results.xls (http://www.formulastudent.de/fileadmin/user_upload/all/2008/Results/FSG08_Dyno_Results.xls)

The given values were measured at the wheels and were corrected for air temperature and barometric pressure.

No 250cc car competed at this event, but it may still help to figure out how much power a particular engine may deliver. You still need to figure out which team ran which engine though.

Regards,

Tobias

[Killer]

Hello, Nvp and I are in the same team. We have decided on the CBR 250 because getting spares and service will be a lot easier compared to the usual engines used in FSAE.There are no bikes from 250 to 650 cc being sold here(except enfield).
Our top priority is to finish the competition but it is hard to accept the fact that the car wouldn't be competitive in the dynamic events.

[Big Bird]

How uncompetitive do you think you might be?
- Will you be less competitive than any team with a 600/4 or 450 single? No, many of them fail to compete, and many more compete nowhere near their potential
- How much power do you need to win skid pad?
- You can throw away any chance of winning the acceleration event as long as you are competing against 85hp+ 600's - just like they are throwing away any chance of winning the fuel economy event as long as they are competing against you.
- You might be slower on the straights - but can you be faster around corners? Which gives a better points return?
- Which will be easier for your driver to wrestle around a 15 minute endurance leg - a mellow 250 or a fire-breathing 600?
- Cost event...

Don't talk yourself out of success. You can get top 10 with that engine. Finish it, test it, sort it, race it.

[Bemo]

Once again +1 to Geoff ;-)

I'd say your decision seems to be made based on quite decent facts. How should a 600/4 make you competitive if you're in trouble of getting spare parts and engines all the time?

No offense, but most Indian teams struggle a lot to make it through scrutineering and to take part in the dynamics at all. So you're on the right track in trying not to make your life harder as it has to be.

Build a simple car that works and that is rules compliant. If you manage to just finish all dynamic disciplines you will already beat quite a lot of teams with much more powerful engines.

[Mbirt]

It's definitely an intriguing engine: http://www.cbr250.org/forums/s...-250-R-Engine-Design (http://www.cbr250.org/forums/showthread.php?20-Honda-CBR-250-R-Engine-Design)

I wonder what the true driving factors for the DOHC design vs. their "Unicam" single-cam-over-bucket or a more traditional forked-rocker SOHC design were... Are ball bearings on the camshaft too expensive for a volume engine? Are valve buckets and machining for the bucket orifice too expensive? The new cast roller rockers at least *look* cheaper than shiny buckets and post-machined bucket bores.

[Big Bird]

That motor looks really interesting. Nice link, thanks Mbirt.

Killer, a favour to ask if I may. Please leave the engine standard. Please resist the temptation to "compensate" for its supposed lack of performance. You don't need to turn it into a horsepower monster, or make it into anything that it isn't already. It has the promise of being a simple, robust and easy to use engine as it is. Run it as standard as possible.

I am asking this because I want to see an Indian team finish top 10. I think you have made a very wise choice, and I think you can succeed where others have failed. A simple and reliable car, well driven, can easily score 600+ points. How many of your compatriots have managed that?

Good luck!

[Killer]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Big Bird:
That motor looks really interesting. Nice link, thanks Mbirt.

Killer, a favour to ask if I may. Please leave the engine standard. Please resist the temptation to "compensate" for its supposed lack of performance. You don't need to turn it into a horsepower monster, or make it into anything that it isn't already. It has the promise of being a simple, robust and easy to use engine as it is. Run it as standard as possible.

I am asking this because I want to see an Indian team finish top 10. I think you have made a very wise choice, and I think you can succeed where others have failed. A simple and reliable car, well driven, can easily score 600+ points. How many of your compatriots have managed that?

Good luck! </div></BLOCKQUOTE>

Thanks Geoff for words of encouragement.We will be doing ourselves a big favor by running it stock.
Our formula as of now is : CBR 250 + Direct acting suspension + Steel spaceframe + Indian parts wherever possible + prepare well for static events + 3 months testing time.

We will be participating in FS UK 2012. Since all classes are merged from 2012 , we have lost the clear advantage we had in fuel economy. We do have an upper hand in cost/sustainability by having a really cheap car but we will have to account each and every part and make a good report to exploit the advantage.

[Adambomb]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Killer:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Big Bird:
That motor looks really interesting. Nice link, thanks Mbirt.

Killer, a favour to ask if I may. Please leave the engine standard. Please resist the temptation to "compensate" for its supposed lack of performance. You don't need to turn it into a horsepower monster, or make it into anything that it isn't already. It has the promise of being a simple, robust and easy to use engine as it is. Run it as standard as possible.

I am asking this because I want to see an Indian team finish top 10. I think you have made a very wise choice, and I think you can succeed where others have failed. A simple and reliable car, well driven, can easily score 600+ points. How many of your compatriots have managed that?

Good luck! </div></BLOCKQUOTE>

Thanks Geoff for words of encouragement.We will be doing ourselves a big favor by running it stock.
Our formula as of now is : CBR 250 + Direct acting suspension + Steel spaceframe + Indian parts wherever possible + prepare well for static events + 3 months testing time. </div></BLOCKQUOTE>

Just have to give you a big +1 on that...that's the mistake we made the first year we ran a single. Went with a super-hot YFZ 450 bored and stroked to 565, high compression, custom cams, etc., etc. Totally underestimated how finicky the singles are. To our defense we did have a top-rate engine builder who was intimately familiar with the engine on the team, but the combination of the hot single with EFI, E85, and a restrictor ruined us. We still haven't fully recovered (although I do have high hope for this year, finally!). And, just as Geoff said, the motivation for that was to compensate, to convince the team that it wasn't a "huge step down" from the 4 we had run for years.

My opinion these days is almost the opposite. Given the absolute hell the restrictor plays with the big pulses from the single, a smaller displacement with a bit more rpm does sound intriguing. And that engine sounds like a great compromise: given its common bore/stroke with its big brother liter 4, it does sound like a really good bang for the buck engine that should give very good performance for its price and reliability.

[Big Bird]

I never got back to this.

" Thanks Geoff for words of encouragement.We will be doing ourselves a big favor by running it stock.
Our formula as of now is : CBR 250 + Direct acting suspension + Steel spaceframe + Indian parts wherever possible + prepare well for static events + 3 months testing time."

The above is the most sensible philosophy I've heard from a new team in years. Bravo! Nothing is a given in FSAE, but with a philosophy like that your have gone a long way towards minimizing your risk and banking a good result. And imagine what goodwill you will bring to your team when you knock off a few bigger teams with "only a 250".

Good luck, and please keep us posted.

Geoff

[vikram.]

if the 2 strokes were still there....

[cvargas]

This year FIT FSAE is running a Bombardier 450. It is taken from a Can Am DS450. I haven't seen anyone else using this engine before. Has any teams ever used this one?

[Mbirt]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by cvargas:
This year FIT FSAE is running a Bombardier 450. It is taken from a Can Am DS450. I haven't seen anyone else using this engine before. Has any teams ever used this one? </div></BLOCKQUOTE>Evansville, McGill, and UAS Graz are the only teams running the Rotax 450 that I know of.

[B Lewis @ PE Engine Management]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by cvargas:
This year FIT FSAE is running a Bombardier 450. It is taken from a Can Am DS450. I haven't seen anyone else using this engine before. Has any teams ever used this one? </div></BLOCKQUOTE>

I am sure that McGill was running this engine. They are running it with our EDGE ECU. We set up the stock crank trigger in the ECU for them. They were the first to use that engine with the EDGE.

[Jan_Dressler]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Mbirt:
Evansville, McGill, and UAS Graz are the only teams running the Rotax 450 that I know of. </div></BLOCKQUOTE>
In case of UAS Graz, there is not much left of the original Rotax 450 http://fsae.com/groupee_common/emoticons/icon_wink.gif

[Mbirt]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Jan_Dressler:
In case of UAS Graz, there is not much left of the original Rotax 450 http://fsae.com/groupee_common/emoticons/icon_wink.gif </div></BLOCKQUOTE>And none of it will remain at all next year, right? http://fsae.com/groupee_common/emoticons/icon_wink.gif

[Jan_Dressler]

I don't know http://fsae.com/groupee_common/emoticons/icon_smile.gif
Only talked to some of the guys from UAS Graz during the last few seasons, so I have an idea about what they had then...
I have no clue what they plan for the future. http://fsae.com/groupee_common/emoticons/icon_smile.gif