Well how far down does the restrictor plate have to be? What does the restrictor plate have to be made out of? Could you say, put an orifice just above the intake valve that was 20mm in diameter but then smooth the intake runners before and after? Then everything except the fuel injector would be in front of the "restrictor plate" just like the rules state but the tuned length manifold would still work like it's supposed to.
Variable length intakes
- Thread starter 'blanshee'man
- Start date
It can be made out of anything (last year it was a custom carbon fiber intake, not tuned just made and thrown in) it just has to be measurable to ensure that it is indeed 20mm. It also can be put anywhere on the intake as long as it is last and it can be however long we deem appropriate. Yes, that would be perfectly legal sicivic
So this;
would be really cool then huh?
Red is the intake valve, silver is the alminum from the head, black is the manifold, yellow is the fuel injector, blue is the tuned butterfly, and green being the throttle butterfly. The peach colored arrows being your 20mm orifice.
would be really cool then huh?
Red is the intake valve, silver is the alminum from the head, black is the manifold, yellow is the fuel injector, blue is the tuned butterfly, and green being the throttle butterfly. The peach colored arrows being your 20mm orifice.
That's pretty cool that your a engineering student and working on engine R and D at the school... As you probably already know the factory bikes are very well thought out and developed.... I read your post and you are trying to bring up the front side of the curve and giving up peak power to a certain point does not matter to you.... My questions are you able to change engine hardware like pistons, epoxy the cylinder head, cam swap? If not can u retard or advance the stock cams..? Will they let u lengthen the stock headers to bring up the front side of the curve? I wonder if you just move back the intake runner a 1/2 inch how much that would bring up the front side of the curve... Anyway your project is interesting and having a dyno u will be able to see the changes that u make... Keep up the good work
I looked at some GXSR 600 bikes that I dyoned...
Here is a link
GXSR_600 | Flickr - Photo Sharing!
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i can basically alter anything i wish, the motor just needs to stay under 610cc's. if i had the time i would love to play different combos and such. but the most ill prolly be able to mess with intake and exhaust and maybe timing if im lucky.
Great points man... Pulling the cam timing out and adding compression will work for sure...
When u say timing is that cam or ignition timing?
Also u could slightly increase the exhaust back pressure to bring up the front side power..... Your lucky to have the facility to make changes and see the results, most people do not have that luxury...
Since U got a dyno to work with, did u already move the intake back 1/2 inch or so... I have seen many bikes fall flat by changing the air box on sport bikes, the OEM has done their homework... PM me or let us know what U have done so far.... Also can U provide dyno charts from the start of your project to what U got now.... I assume u are using a dynojet or land-and-sea dyno
Sorry cam timing. I know its 12:1 compression right now im not sure what stock is. And we are planning throwing the stock header back on which im told has a butterfly valve in it for that reason. We have not done any preliminary testing yet this year but i should be able to dig up what it made last year. Im actually not sure which kind of dyno it is, i havent seen it yet but ill ask around tomorrow.
If the school will allow picture taking, snap some shots on the dyno...
12:1 sounds like stock to me
Keep us posted man
Retard cam timing 4 degrees and bump up exhaust valve size. increase intake charge length as well. I have plenty of flow charts in solid works to back up velocity vs intake length and how it hits.
Shorter runners are always gonna net bigger high-end numbers and longer runners and shallower plenum is gonna give you better low end.
Bowel work in the head is gonna be a huge plus too if you can have that much time. I would not worry much about the low end of the things rather the flow end
This can be achieved with modulator rings like in a previous post i ave made here. Hook up a vacuum gauge and watch the vacuum drop down. This is gonna hamper other areas but you will get my drift once you do it.
That Renault f1 engine has been used in this discussion on many boards as well.
Loving the fact more and more tech discussion's are being posted here.
Shorter runners are always gonna net bigger high-end numbers and longer runners and shallower plenum is gonna give you better low end.
Bowel work in the head is gonna be a huge plus too if you can have that much time. I would not worry much about the low end of the things rather the flow end
This can be achieved with modulator rings like in a previous post i ave made here. Hook up a vacuum gauge and watch the vacuum drop down. This is gonna hamper other areas but you will get my drift once you do it.
That Renault f1 engine has been used in this discussion on many boards as well.
Loving the fact more and more tech discussion's are being posted here.
Dude solidworks flow charts would be sick if you could would send them to me maybe?
Ok so some updates and answers.
1.the group and i have decided we will not be using a butterfly valve. instead we will have some sort of oblong canister that will rotate and increase in length as RPMs increase. When i have a concrete picture or something ill post it up.
2. we have access to a land and sea but if we wanna travel a bit we can have access to a 60 horse electric dyno.
3. we are now looking for ANY exhaust for a sports bike in the 600 cc range
4. A task ive been charged with this week is figuring out the optimum finish on the inside of the intake. Like the dimpled golf ball theory i just have to figure out how much or how little is best...
Ok so some updates and answers.
1.the group and i have decided we will not be using a butterfly valve. instead we will have some sort of oblong canister that will rotate and increase in length as RPMs increase. When i have a concrete picture or something ill post it up.
2. we have access to a land and sea but if we wanna travel a bit we can have access to a 60 horse electric dyno.
3. we are now looking for ANY exhaust for a sports bike in the 600 cc range
4. A task ive been charged with this week is figuring out the optimum finish on the inside of the intake. Like the dimpled golf ball theory i just have to figure out how much or how little is best...
There is more than one team working on the car. My group has the engine and drive-train. There is a frame group, a suspension group, a controls and ergonomics group and a body group. There are also 8 events or just places to be judged in. Cost, design, marketing, acceleration, skidpad, auto-cross, endurance and fuel economy.
nope only five groups and each group has 4-6 people in it, still alot of people. It is alot of people but everything except for the engine needs to be made every year. You need to design and fab your frame and suspension aswell as making the carbon fiber body cover ourselves.
if i remember correctly harley davidson actually started this on there bikes. yamaha later bought this idea from them. i think it was first adapted to v-max. which was and engine designed by harley. lots of other manufacturers later followed. even some in cars. lexus 1uz uses this in there intake with 4 butterflys in the intake. it works off of vacuum. some systems work off servos.
generally longer for low rpm power shorter for high rpm power. some shop math is 132000/rpm= velocity stack tuned length inches. also play with a lil valve overlap. more overlap less low end and less overlap more low end. advance the intake cam a few degrees for some more overlap. ;-)
generally longer for low rpm power shorter for high rpm power. some shop math is 132000/rpm= velocity stack tuned length inches. also play with a lil valve overlap. more overlap less low end and less overlap more low end. advance the intake cam a few degrees for some more overlap. ;-)
