I feel that we under use the term "butt-ometer" around here, I think that as a collective we ought all get behind it. Fully behind it.
Butt-ah-met-ur. That's how I say it, anyway. Fun fact: my dad would pronounce "speedometer" as "speed-oh-meter," and it would annoy the hell out of me. The first time I ever heard him say that, I thought he was joking, but he just kept doing it. I asked him why, and he said that he didn't know why, he'd just always done it that way.
Yes, we do. And you dumb fucks fine gentlemen south of the border probably call this "why why zeeee" But ZZ Top is and always will be Zee Zee Top
Why is it like that? I know exhaust length has a lot of impact on scavenging and engine performance and exhaust note... did they just need an extra 3 feet in there for some reason?
That's some pretty stupid analysis. If you're going 65 in 40, that's relevant. But, there isn't a posted speed limit where 198 is just a little over. That's like comparing the surface of the sun temperature to water's boiling point. "New instruments today show the sun is over 5300 degrees Kelvin hotter than boiling water." There has to be some relative scale worth comparing. "This is slightly faster than a passenger jet at takeoff." Or, "these are near the top of NASCAR race speeds."
Our top speed, going flat out at the 24 hrs of Daytona, down the back stretch, wide open throttle for 20 seconds, was 192 mph. In a full-on Porsche, purpose built race car. And that was the scariest fucking thing I've ever done. (Altitude really helps make aircraft speed much less scary than it is... if shit breaks, you can fall for a while before you pop a chute or hit something hard).
Because it was designed by some numb-nuts at Chrysler LLC. It's like the engineers got bored one afternoon, and started fucking around with stupid designs as a gag, but then forgot to revise it for production. Friday afternoon: "Can you imagine if we made it like this?! That would be soooo dumb! See you guys on Monday!" Two weeks later, in the technical supervisor's office: "Have a seat. I'd like to discuss your new design for this catalytic converter down pipe..." Nett, mark my words, there is no way in hell that loop was put there for any sort of scavenging effect. Here's what I think happened (for real, this time): This was a Jeep Liberty or Renegade (I don't remember) with the newish 3.6 V6. They were probably trying to find a way to use the existing intermediate y-pipe with the new engine and picked the least efficient way possible to do it. Mopar: the discount version of Ford and GM.
pretty much. the dodge 1500 with coil springs in the rear are not held in place except by the compression. if you unload the suspension you can just pull the coil springs out. and a bunch of other dumb stuff I cant remember.
Okay guys, I did a little research about that weird-ass exhaust loop yesterday, and I was wrong on two counts: 1) It was a 2014 Jeep Wrangler (I actually looked back on our reports from that day), and 2) That loop is there to equalize the lengths of the exhaust pipes before they merge (so Nett, it looks like you were right). There is A LOT of bickering about this on Jeep forums, some guys saying that it is crucial to performance of the 3.6 Pentastar V6*, others saying that is was just job security for the engineers. There are a few companies that make "loop delete" kits for the 2012-2018 Wranglers (and this loop is only found on the 4-door models, by the way), and there are plenty of guys who swear they gained power and mileage, but just as many that say it hurt performance and economy. Unfortunately, I couldn't find any back-to-back dyno tests of these claims. I will say this: I have not seen this on any other Mopar vehicle with a 3.6, be it Ram, Charger, Grand Caravan, etc. Perhaps the engineers found some minute benefit in this particular vehicle that justified its use; the prevailing sentiment among owners is that the 3.6 needs all the help it can get when it comes to making power. * AKA "Tickastar," AKA "Steaming pile of shit." Seriously, just google "tickastar"
When we would make custom exhaust manifolds/collectors and turbo plumbing we found that there is actually science behind it. (Who knew!) I dug through some racecar engineering textbooks and found some basic math that we had to follow in order to get shit working and sounding right. We had 2 manifolds that were almost identical for our race car. One worked and sounded awesome, the other was just “off”. Turns out two of the collector intakes were about 2” shorter than what they should have been, theoretically, and it was noticeable. It was a hell of an epiphany.
By the way, if anyone is interested in the engineering behind race cars, I've subscribed to a magazine called (go figure) Racecar Engineering for years. It's crazy informative. Sure, it focuses on higher end race cars (F1, Indy car) but it has some pretty interesting "this is how the tech behind X works" features. Makes for great bathroom reading, if you're into that kind of stuff. http://www.racecar-engineering.com/