| Author | Message | ||
     Wet4uracing |
I am in the process of doing a twin carb(cv)conversion on my s1wl.Has anyone here done this before? If not ,why not?..............stu | ||
| Kahuna |
Question to those with the force on an X1. I read over at ATC that you need to grind the IAT sensor when installing it? I've finally decided to get it, and want to know what's involved during install. Also, has anyone relocated their horn to behind the windscreen? how? pictures? Thanks everyone for all you help  | ||
| Skulley |
While were on the Force intake thread, has anyone polished the inside of it? Car intakes are polished for a claimed improvement. | ||
| Shooter |
 polishing a force... I have heard that a little turbulance is good for the air, but would love to hear the opinion of some of the more learned folk on this topic...I have thought the same thing, but at the velocity vs the area I am not sure there would be any noticible delta...would sure look cool though.  | ||
| Blake |
Turbulence inside the combustion chamber is good. Turbulence within the intake tract is bad. At WOT you probably won't see a difference. But, things are cumulative and every little bit helps. I understand cleaning up the intake manifold even "porting" it so to speak is a worthwhile undertaking.  | ||
| Pammy |
polishing the intake is not necessary... porting and blending is good though. There is a boundary layer of air that acts as a "smooth surface" in the intake. | ||
| Pammy |
I should say a "smooth, insulating surface". If the intake surface were too smooth(polished) it would create friction which in turn would create heat(however minimal) which would warm intake air which is bad for performance. | ||
| Ara |
The rougher the surface the thicker the boundry layer and the narrower the effective opening. Fluid dynamics. | ||
| Blake |
Pammy, I agree, polishing won't get you anything, but you are reaching on the friction thing. Don't make me whip out my big book on fluid dynamics. | ||
| Road_Thing |
Pammy! Hush!! Don't start him to figurin', he makes my nose bleed! r-t | ||
| Chrism |
Not being versed in fluid dynamics, I can only speak from practicle experience. Having a polised surface in the intake tract creates a thicker boundry layer. The first layer of air actually sticks to the port walls. The next layer has a difficult time moving over the first and so on until eventually one sees top velocity. What we have found is a rough intake port will actually make the first layer of air tumble allowing the next layer to slide over it at maximum velocity. Similar to the roller tracks at Service Merchandice. Try pushing a flat box on a linolium floor, then try it with your kids pick up sticks lined up underneath. Much easier. The exhaust port does benefit from being polished. Only because carbon has a harder time sticking to a smooth surface. I belive that were there no contaminates in the flow, a slightly rough port would have the same effect as the intake. Only my personal observations, but NASCAR doesn't Extrude hone their intake ports either. | ||
| Pammy |
Blake, I added "(however minimal)" but it is there. If you have ever been involved with serious racers and seen some of the bizarre things they do to overcome the "minimal" losses you would understand why we do some of the things we do. It's all a package, you know a 'big picture'. Replace a footpeg or some other frame part because the new one weighs 2oz lighter. Take all the oil out of your crankcase save a few ounces to reduce that parasitic loss. I have even know of one well-known racer who put nitrous or ppo (I can't remember exactly now) in his crankcase and then vented the breather back into his intake. They don't do oil checks in racing, only fuel checks. My point being the fact that racers take every nuance of physics, chemistry, etc...to it's very extreme, so the heat(however minimal) would be an issue. So, whip it out if you must. I stand by my statement...(keep in mind that I am B.L.O.N.D.E.) | ||
| V2win |
Blake, if you "whip it out", let me know in advance. I dont want to be around when Pammy starts laughing. | ||
| Sarodude |
The 'too smooth' intake thing is much discussed in many areas. I'm fairly certain that I buy off on it. However (I know I'm going to regret this), what's the proper roughness? I mean, if we were going to do something silly like line the intake with sandpaper, what grit should it be? Are we so lucky as to have the ideal grain already in there? -Saro | ||
| Ara |
My understanding is that a certain amount of surface texture is good everywhere downstream of where the gas is introduced into the airstream. If the surface is too smooth, the gas can actually bead up on the surface. But upstream of that, I would think that the smoother the better. Blake, you'd better whip our your fluid dynamics text, because some authoritative input is quickly becoming a necessity here! Russ | ||
| Sarodude |
OK... Let's make sure we're making destinctions between observed Dyno measurements, puddling, and flow... -Saro | ||
| Pammy |
Fluid dynamics is all about air flow! What makes a golf ball travel 200 yds(I'm not a golfer) rather than just 100 yds when smacked into the air? When golf balls were smooth, they didnt' go very far...add dimples and Voila! Tiger Woods! | ||
| Ara |
Yup, back in the '50s they designed fighter aircraft using a thing called "area rule." Aircraft designed in this way have a very characteristic "coke bottle" shape to the fuselage. The waist was essentially a big dimple. But Tiger Woods doesn't know anything about this. | ||
| Hans |
Dimples on golfballs make the counterspin more effectfull which helps them flying upward and stay high. (How should I know, I am not a golfer.) | ||
| Mikej |
Dimples on golf balls also allow for a wicked slice that can perfectly follow the contour of a small pond. I almost had that slice perfected.  oops, off topic, running and hiding, bye | ||
| Ara |
Does anybody know how I could dimple the interior surface of my airbox? | ||
| Reepicheep |
The dimples take the smooth flow and introduce small vortexes, and do in fact increase airflow... Or at least they did on a particular commercial jet engine nacelle in the 70's. Don't know why it never showed up in production, but it looked good in test. The term I heard thrown around was "non-laminar airflow". My assumption (and no doubt mental oversimplification) is that a air molecule being drug along the wall for the length of an intake slows down, but if you can introduce a bunch of little vortexes along a surface they can act like a whole bunch of little tiny "air bearings". Instead of dragging air through, you are sliding it along rollers.  Or maybe not... | ||
| Sarodude |
I don't think anyone is questioning the dimpling thing. However, WHAT'S THE RIGHT SIZED DIMPLE? Spacing? Pattern? What, no aerodynamicists lurking around here? Should we all heat our intakes to just under melting and roll a ceramic golf ball on 'em? -Saro | ||
| Blake |
The dimple size is relative to mach number. The turbulence does not act like little bearings, the turbulence prevents buildup of a thick boundary layer of laminar flow. A thick boundary layer in an intake would in effect reduce the diameter of the intake tract. Like I said, for a short intake, especially one with a 90o elbow, any smooth versus dimpled versus rough finish is negligible. You want a significant improvement in intake flow? Straighten out the intake tract. Now, when you talk about LARGE surfaces subjected to well developed flow like on an airplane wing or engine nacelle, intentionally instigating turbulence at the boundary layer can be VERY valuable in assisting desirable aerodynamic behavior. | ||
| Kahuna |
Mission Accomplished!! After 5 trips to the hardware store, I have finally installed the race intake from the S3 on my X1. Got some fuell line and routed the breather to all the way behind the lic. plate. All looks FANTASTIC! Now just have to order the tank accents from ASB, and I'm all set!  | ||
| Sportyeric |
I have dutifully searched to be sure I'm not being repetitious (this time) and I find that nobody here seems to have reported that the PITA intake manifold bolts can be replaced by 12 point bolts from Caterpiller, part number 1T-0416 or from ARP Bolts, part number 612-0750. (More trivia from the XL List) | ||
| Johnnybravo |
have you ever thought of rifle boring your intake to create a vortex in the combustion chamber. When i had my heads ported i had the exhaust side polished and my head guy put a fin on the intake side to push the air around the valve stem to create alot of unstable down ward air and fuel (more turbulance, better atomization, better burn) and because that worked so well i am going to buy an extra intake manifold and rifle port it to see what the advantage would be if any | ||
| S2pido |
Sounds just like a Turbolator! Great power and mileage addition to any HD intake stream. Just ask Aaron! | ||
| Archer |
 I have heard alot of different crap about the hyper charger. i think it lookd really cool but i don't want aomething that will perform like shit. I have also been told not to buy a forcewinder. What performs the best????? Any one found anything unusual???? | ||
| Johnnybravo |
alot of peole say the hyper charger works and that the effects dont show up on a dyno cause you have to be moving to get the "ram air" effect. Makes sense sort of. If you look at the bottom of a hyper charger you will see a slot for ideling purposes which looks like the "ram air" will go straight out the back  Force winder is a good one never used one personally but herd alot of good things, unless you ride in any weather thats when i becomes a problem. I put an old S2 air cleaner (slightly modified) works the same as a pro series. But it is all personal taste i guess.  |
