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Svt motor, gertrag trans, means no trans parts, no final drive options, and does it have a limited slip? Then which tire do u use to compute the ratio. And while the Svt loves to rev, like others have said, has he past the point where the tq is lost.
 

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Discussion Starter #22
I was told by a guy that did the math that i dont no i should run a tire size around 77" to78" diameter.. But that was to crank around 7000 rpm.. Ill go bigger diameter to less rpms and try it.
 

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7 grand is fine but you have to have rev room under that, the purpose of having a power BAND. You try to achieve lower rpm at the turn exit so that you have rpm to pull up through on the straight to try to hit max rpm 9but ONLY momentarily) at the end. If already close to max rpm you have nothing left to accelerate with.

Sperber is right, SVT is supposed to be a 6 speed unless somebody changed that, and even more of a reason to use 3rd gear. 2nd would be like an extended low gear and useless, you have no higher pullout speed, you are out of gear too.

Where are you going to get a 77" diameter tire? You're spouting with no thinking there, no insult intended of course. Maybe talking rollout or circumference.

You figure both tire sizes and the gear is the middle in between, the diff splits the rpm to both sides. Badly need a P-Trac there like said.
 

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Old Phart
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Use a calculator like this to help get in the ballpark where you can use tire calculators to find the size that gives you about the diameter required:https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=13&cad=rja&uact=8&ved=0ahUKEwiEisu69YXUAhXD4iYKHYIfBa8QFghdMAw&url=https://www.omnicalculator.com/math/circumference&usg=AFQjCNFC1Ii-f_eN7m5cKV1oiv_HwOgfxg&sig2=bC0ZyRvn1Vc6JkmyYvf7VQ

That's for conversion of circumference (the number you are referring to as diameter) to actual diameter numbers posted in tire calculators.

Circumference is the actual distance around the tire, as if you wrapped a string around it & measured the length.

That IS the measurement actually used for stagger calculations, since it's the most accurate number available for how far a tire will travel on each turn and it's easy to measure. Your 77" number yields a 24.5" diameter BTW, but there are odd digits in the thousandths as well to that conversion - an example of what I'm describing for accuracy.

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Try measuring the tires you are running now up front for actual circumference (measuring tape around them). That'll give you more info. on how they relate to that calculated number you mention & how they relate to each other.

I think you're going backwards for the stagger used, but without a limited slip it might even be helping you. Your use of a smaller width outside tire reduces traction a bit at the right corner, what I think you're feeling is how it can throw power to that same wheel as it's turning faster than the inner wheel. Might even 'trick' the differential to avoid inside wheel spin as a positive effect.

The usual idea for stagger is to have a larger outside tire, so while making your left turns both wheels turn at closer to the same RPM & power is more evenly split between them.

Throwing all the power & much of the cornering load to the right front CAN make the car 'tight', tending to understeer and move up the track as that corner loses traction. Before traction is lost though, it should try hard to turn left for you.

I can't guess at your corner entry speeds, or how much traction you manage to get out of the RF tire. What I'm imagining in theory is something that currently feels good at lower corner entry speed, dragging you nicely around the turn. Get faster on the straights, and you may find it washes out in the corner with a faster entry speed. Just keep that in mind as you experiment with what works for your setup.
 

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As long as I'm talking handling, FWD around a long turn (1 & 2, 3 & 4) is 'balanced' when you can round the turn at moderate throttle without moving up or down the track. Not loose OR tight.

Add throttle and it gets tight, moving up the track toward the wall. Reduce throttle & it loosens up, moving down the track (if you don't overdo it & spin from a sudden input).

FWD in general tends to be 'tight', and most handling adjustments are made to loosen it up.

Oh Sheet moment for me in solo testing at a local track that tightens up in turn 2 was from coming into #1 too fast. Drifting toward the #2 exit wall, just hoped to scrub off enough speed to avoid kissing it. Setup a bit tight, so couldn't get it as sideways as I wanted to scrub off speed. Neutral drift was all it would give me with no throttle at that point.
 

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Discussion Starter #26
Yes nicely put guys... This info will help me alot.. And yes the tire measured. 77 " around center of tire with tire pressure i was running as you said. Idk hiw guy come up with that but thats what u started at. Im the only one at track with a focus so most guys wont and cant help.. But my setup sat night was perfect.. I ran a 35 lap race and only tire that grew was right front by two pounds.. So at that point i took it as car was pretty balanced. I was acually a little lose is center of turn but it seemed to help the exit with out the (push)/ pulling to the wall on exit. But with the good explanation on the gear i will try to running 3rd gear as you said.. And guys i cant thank you enough for the help... I really appreciate all this info i can get
 

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I like this thread. [hihi] because I love short tracks. [hihi]

I'd really like to watch some videos if the OP's home track has a website.

Made me throw up in my mouth a little when the OP said he's getting beat by a cavalier?..I was like wtf?!?! [headbang]
 

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Discussion Starter #29
Yea the cavaliers thing makes me sick lol but these arnt normal cavys lol.. And for runing 35 laps and one yellow and only gaining two pounds in right front is not bad i dont think.
 

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Discussion Starter #31
Heres another question for you all... My kill switch has to shut car down. How do i hook the kill switch up so car will completely shut off when its turned off
 

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That is fun stuff, first review the instructions on the switch u r using, if it's a two post with a built in Circuit breaker or actually the one with four electrical posts, it's designed to take away the shock the electric system sees when switched off, it acts as a draw to prevent the alternator from continuing the circuit. Again it depends on which switch u have or are required to use in your rules package. These do fail over time and the diag of these are a pain, intermittent skipping from the motor acts like other stuff, we carry a spare and just replace at the end of the season as a precaution. Others have never had an issue but that one time will take forever to test out.
 

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Discussion Starter #33
I have a two prongs.. I tried doing negative to the batter but car still runs. Thats what the switch said to do. Then i tried runing from the alltinater and shutting that down.. And car still runs.. Idk what to do to get this car to just shutoff with switch
 

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Your alternator is still energized, your switch u say has two poles, are they just for the battery cables, if so you may not be able to use that switch, the switch I am thinking of has two poles for battery cables and four electric spades to remove power from the system without shocking the alternator. Which switch do you have?
 

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Moved this to Road Racing & Rally last night, best fit we have for Circle Track to post. System went down before my message to that effect posted, along with comments on finding switch info. here or in MkI sections.

For battery disconnect switch that'll actually kill it for sure the Alternator protection types with the extra connections mentioned would be what to research. Without shutting that down properly you still have ignition turned on, and alternator can continue to power the car.
 

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Thats What She Said
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you need something like this...

https://www.summitracing.com/parts/lng-45782/overview/

you run the alternator directly to and through the switch to the battery as well as the battery to the switch to the distribution / fuse box.

4 posts:
Alternator > Switch > Battery
Battery > Switch > Distribution

Switch in off position brakes both connections.
 

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Discussion Starter #40
Okay iv got it now.. Hook batyrry to kill switch with ignetion to it also.. Once i switch it off now everything dies.. Thanks guys... And i would love to have a sticker to put on this car.
 
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