Guys,
I just can't help myself. I have to know. Now, if we were driving and talking about Dodge Vipers "up in here," then I might not have to know. But since our top speed is going to be in the 100 - 110 mph range, I can handle that.
This just cropped back up in my mind because last night I was watching a couple of Space Star / Mirage videos of them out on the Autobahn. In both cases, the cars were 5 speed (race)cars. One was the latest generation car, yeller in color. Sharp car. I could tell he had futzed with his exterior light bulbs because his blinkers were blinking way too fast.
Anywho - something occurred to me as I was watching the videos. They were hitting top speeds of about 160 to 165 kmh (102 - 105 mph). One time a little faster but it was slightly downhill so I neglected it. And also, at least the 78 hp yellow new one was only able to pull ~4,500 rpm in 5th, and ~5,500 rpm in 4th. And that's when it struck me!
I bet they're running that 3.55 differential ratio in those German cars! And, there's a sporting chance that our 'Merican cars might be faster than them fancy German cars!
While the 3.55 might (probably does) yield better mpg than the 4.055, I have a feeling the 3.55 may produce better top speed results.
A quick relative story. Back 100 years ago, I raced motorcycles. On racetracks and the street. One of the smart guys I rode with on the street suddenly made his bike faster than another guy's exact same bike. Nobody knew why. They would ride side-by-side at top speed just the weekend before. Those bikes wouldn't pull to redline in 6th gear. But Danny changed his rear sprocket and his would pull either to redline or a lot closer to it than Bud's, extracting a bit more hp ... resulting in 2 or 3 more mph over the indentical bike Bud had. Bud was fuming for hours about how Danny could pull away from him. This (fun) went on for hours while Bud tried to get it out of Danny what he was doing. Danny was all mum. Then I noticed Danny's shiny new rear sprocket, and pointed it out to Bud. It was all such a hoot and fun. But that quick easy little change put Danny ever so slightly ahead of Bud.
We may be in the same boat here with our 4.055 versus the 3.55. Our cars should be able to pull closer to redline in 5th. I think our cars can hit redline in 4th, or much closer to it that 5,500 rpm.
So, as a result of this curiousity of mine, I'm just going to have to find out. I'm going to have to set up an "experiment." I just hope I don't get caught "experimenting." I can't give a date yet. Only I want to get this done this spring. I'll have to set aside some time on a Saturday and drive down to I-16 in south GA. That interstate gets fairly desolate and empty the further you go east of Macon ... until you start getting close to the coast. And it's fairly flat too.
I'll take a day and find a level 3+ mile stretch with decent pavement. I run a dash cam with a GPS, so that should take care of the documentation. Oh, that reminds me. The German's autobahn Mirages / Space Stars were showing 160 kph to 165 kph, ON THE SPEEDOMETER. We all know there is error. At 100 mph, there's probably close to 5 mph optimistic error. Cause I know I get about 2 mph error at 70 mph. So, let's just say there's 3 mph error and that's safe. That means their cars were doing more like 99 mph to 102 mph (instead of 102 mph to 105 mph).
Am I crazy? Does anyone disagree with my numbers for their speed? I'm going to say their top speed is 102 mph. Does anyone (verbally / mentally) agree with my experiment?
Below are the rpm to gps corrected speeds I'll be working with (4.055 gearing). Meaning, if I can pull more than 6,254 rpm in 4th, or 5,173 rpm in 5th, then our cars are faster (because these speeds are gps corrected). However, my dash cam displays speed too. And the dash cam speed does say 70 mph with my speedo is about 71.5ish. So I trust the dash cam speed is the more accurate one.
7milesWAYoutTHERE