Right now I'm running two 2200kv motors with 34/40 gearing and the motors are barely warm. I have a feeling when I drop in my 36/35 setup they will get hot and I'll max out around 110mph.

I've learned you need torque to run taller gearing, the 1717's have that which means I can push taller gearing and go faster. My issue then becomes radio range and gearing.

My worry is the effective gearing you're able to run may not be enough to make up for the loss of kV.

Well I'll be the first to tell you idk much about BL. It's not as simple to just drop this and that setup in. Stuff is expensive, unlike my nitros. To go twin 1717's with new lipos I'm lookin at $950. Thats why I like nitro, $300 and I got a sick motor lol

I need to max out the 2200's and then figure out the next move. I could easily get one 2028 combo for $360 and run on 6s or 8s. Which is the route I may end up going cause it's much much cheaper but honestly all these routes sound amazing lol

I may be out of line here and not understanding something but, I thought gearing was as tall as it gets at 1:1. Once you start going, in your case, 36/35, doesn't that start lowering the gearing?

Whats the difference in having a 60t spur and 20t pinion or a 20t spur and a 60t pinion. Won't the vehicle go the same speed?

As for your motor selection, you can find Leopard 92mm cans with almost 1800kv. I don't think they are made new anymore but when I was looking for my 1492kv 4092 motor I saw a couple. I can't however tell you whether they can handle 8s however, I have had great luck and moderate experience over volting motors with no ill effect.... except on a 15t brushed motor.

No.

For example a 25p/50s is a 2:1 ratio, 50p/50s is a 1:1 ratio, 50p/25s is a 1:2 ratio.

So, for every 2 turns on the pinion, spur turns once @ 2:1. For every 1 turn of the pinion, the spur turns 1 time @ 1:1. For every 1 turn of the pinion, the spur turns 2 times @ 1:2

I've successfully ran 0.9:1 gearing on my nitro savage to 65mph. I believe my attempt to run the same on my twin I should reach 110mph. Now I'm trying to figure out how to reach 120mph and all my options lead to lower kv motors cause they have more torque.

Here's a question, my twin flux weighs 15lbs as it sits with batteries installed. What about trying two 2650kv motors, don't they have more rpm than the 2200kv? I know they have less torque. Or what about trying the actual castle 1515 which has 10000 more rpm?

2650kv on 8S ? what motor is that ?

Oh sorry, I would run the 2650 on 6s, some have done it without any issues.

The 1515 designation Castle uses is borrowed from Neu and indicates motor size. Neu produces 1515's in a variety of kv's. Castle only makes the 1515 in 2200kv and the HPI motor is basically the same. The Castle 2650kv is actually a 1512 size which is slightly shorter than the 1515. The 1512 2650kv on 6s has been done plenty of times by buggy guys for speed runs.

Idk what else your current setup may have left in it as I'm not there. I would be tempted to cut the rear wing down like the top speed buggy guys do. They usually cut the horizontal parts out to reduce drag but leave the vertical sides as stabilizers.

If it was my truck I'm not sure if bother with dual motors unless I kept the current esc's limiting it to 6s. I haven't done the math but you may be losing too much rpm goin lower kv and may not be able to make it up with gearing alone, may have to go 8s. If that's the case then I'd go XL2 esc and one of the Leopard 56mm diameter motors with the highest kv I could get. The Castle 2028 is 750kv and there's a few Leopard 56mm over 1000kv.

How tall are the wheels you're running? I'll do some calculations later after work as you got me curious now.

I know what your talking about with the rear vert stabs. I may try that :)

The wheels are 105.5mm tall but I'm sure with the wear they have received there around 102-103mm however I do have a brand new set that I'll be running next time, so those are 105.5mm.

I was reading last night that the castle versions from the 1512-1717 are rated to 5-6hp. Something tells me that would be the 1717 with that figure but idk. I've always guessed that I'm running between 6-7 hp in my setup.

Those numbers sounds a little optimistic (as usual on the web). A 1/8 scale 6S system, like the Mamba Monster 2200kv combo, typically puts out around 2000 watts (2.7hp). The 1717 about 30% more (3.5 hp).
Your guess is just about right though. A twin setup would theoretically give you 5.4hp then.

Ever considered running the twin 2200's on 8s each? would require 2 xl2 but they aren't expensive and do datalogging. I run one in my speed run rail.

Can the hpi flux torque motor handle 8s?

If that's the case then one 2028 which is rated at 10hp should be more than enough to reach 120mph if I can have gearing made for it. But it falls back to distance to run and the radio

I'm going to say no. 8s fully charged will spin a 2200kv to 74,000rpm, well over the 60,000rpm limit. But over revving the motors could be avoided. I'm not sure if you can avoid them melting down though.