Summit Point weekend recap
11-08-2010, 10:26 PM
#1
Melting Slicks
Thread Starter
Summit Point weekend recap
So I completely outreached any sort of goal I set for myself this weekend...
Long story short, new gearbox and cold weather (with old tires), added up to me running a 1:16.72.. My previous best was a 1:17.7 in similar conditions. Best part is that the data shows theres a 1:15.high in there somewhere if I don't screw up.
Heres a plot of my rpm's w/ the new box (orange) vs/ the stock MN12 (blue). You can clearly see how much more time is spent up high in the rpm range, never dipping below 4k, all adding up to a higher average HP utilized.
Heres GPS MPH of a 1:16.7 (orange) vs. a 1:18.00 (blue) and the time differential (pink)
as you can see I'm giving up some in T4 and T5, and i missed 5th on the back straight... so I coasted to the finish for the 1:16.7
Also, my Left inner CV boot spewed grease everywhere, and I pretty much ran the entire weekend w/ it like that... Should I replace the axle or just put a new boot and grease on it?
Long story short, new gearbox and cold weather (with old tires), added up to me running a 1:16.72.. My previous best was a 1:17.7 in similar conditions. Best part is that the data shows theres a 1:15.high in there somewhere if I don't screw up.
Heres a plot of my rpm's w/ the new box (orange) vs/ the stock MN12 (blue). You can clearly see how much more time is spent up high in the rpm range, never dipping below 4k, all adding up to a higher average HP utilized.
Heres GPS MPH of a 1:16.7 (orange) vs. a 1:18.00 (blue) and the time differential (pink)
as you can see I'm giving up some in T4 and T5, and i missed 5th on the back straight... so I coasted to the finish for the 1:16.7
Also, my Left inner CV boot spewed grease everywhere, and I pretty much ran the entire weekend w/ it like that... Should I replace the axle or just put a new boot and grease on it?
11-09-2010, 07:14 AM
#2
Burning Brakes
Member Since: Nov 2008
Location: Gaithersburg MD
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Congrats on the lap time. I can only dream of a 1:16, still at 1:25 myself.
Looks like the new gears are significantly closer ratios. Specifically, the change in rpm when shifting 3 to 4 is much smaller than before. What are the ratios of the new box?
Looks like the new gears are significantly closer ratios. Specifically, the change in rpm when shifting 3 to 4 is much smaller than before. What are the ratios of the new box?
11-09-2010, 11:52 AM
#4
Safety Car
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Great time Wally --- It appears that the mods are producing results !!
On your half shaft, I would just get a rebuilt one and install. NAPA or other such store - they are not that expensive and want your old one for a core. It is a real PITA to disassemble the CV joint to install a new boot. About 30% of the time you can't get the joint apart due to wear and end up getting a rebuilt one anyway. Don't even think about a split boot or a stretchable one, they will NEVER hold up under your type of usage.
On your half shaft, I would just get a rebuilt one and install. NAPA or other such store - they are not that expensive and want your old one for a core. It is a real PITA to disassemble the CV joint to install a new boot. About 30% of the time you can't get the joint apart due to wear and end up getting a rebuilt one anyway. Don't even think about a split boot or a stretchable one, they will NEVER hold up under your type of usage.
11-09-2010, 02:21 PM
#5
Melting Slicks
Thread Starter
I had read somewhere that the rebuilt shafts have much thicker/more brittle boots and sticking w/ oem was the way to go. Anyone have input on that?
