About 24% if I’m inputting the right numbers. Still seems high but it’s definitely holding and im seeing a clear RPM drop between gears.
7875 + 5.9 + E85 + Megasquirt
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TT5.9mag
Two atmospheres are better than one
Thats VERY high.
Yeah. Beats the f$&@ out of me why it’s so high. Maybe the numbers would look better in the 1/4 but I’m crossing the line at 6000rpm in the 1/8 with a 3.23 gear and a 27.5” tall tire.
TT5.9mag
Two atmospheres are better than one
In 3rd gear?
Put some old school Super Tricks on.
Yup
TT5.9mag
Two atmospheres are better than one
With no slip I’m showing you should be 4578 rpm
Turbosmblk
Well-Known Member
You need gear, run it in the 1/4, or be willing to live with sacrifices. If it gets tight enough to pull less than 10% with your current setup it’s going to be so tight it won’t accelerate.
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It’s all about compromises, right? Street vs strip, big vs low budget, reliable vs not-so-reliable. And we can just throw MPG out the door. That ship sailed a long time ago. lol
Turbosmblk
Well-Known Member
No doubt. You could always put a 46re in it so you can up the gear. Non lockup input shaft and you can run your current converter too.
Yeah that would be great with that 0.69 overdrive and like a 3.91 in the rear.
Turbosmblk
Well-Known Member
Just reading over everything again I did some calculating. This is all through the Hughes converter slip calculator online. But with a 116mph trap at 6k and 3.23 gears my numbers show 30%. Previous numbers at 112 show 40%. Somewhere our numbers are off. Either way slip is still high. Another option would be run it like a glide in 1st and 2nd and leave high gear for cruising. If you have driveshaft rpm we could see what those numbers look like at the top of 2nd gear to determine efficiency if running an OD or putting gear in it isn’t an option. Also going this route you might could even take a bit of gear out of it and leave on more power with a brake to compensate the loss of SLR. which would make it more forgiving on the starting line.
Just thinking out loud as there are multiple different ways to get the outcome you desire.
Probably the most budget friendly test would be to run a shorter tire to mimic the effects of a taller gear. Thinking about OD and building a new third member with taller gears just makes my wallet sweat with anxiety. Lol
Well tonight’s tnt outing was a bit of a bust. Got 4 runs in, one decent time and one that was on track to be a new personal best but the tune went lean and the safety trigger killed the engine. I still have the shimmy in the rear and have a new problem. My fuel pumps are not keeping up with the demand. Fuel pressure nose dived on my first run when I turned it up to 23psi. That’s what leaned out the AFR and cut the engine. I coasted through the line at 93mph and still went a 6.79. So disappointing because it hooked good and was pulling really hard.
This was my first run where it cut out about half track.
I was talking to a guy at the track that owns and tunes a stable full of 1000+ HP cars and he also suggested my rear gear was too tall. He suggested something in the 3.7x range would be a better fit.
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