Maybe someone here will know the answer to this.

Reworking front end on FED. long story short I can now move few items more forward. Fuel tank 4.2 gallon filled to rim. Can be moved 6" towards axle. Battery(45 lbs) can be move forward of axle. Has been against axle now can move 6 to 7" more. Figure should act like more weight on axle while being same weight in actuality.

Quesion is. Will moving 45lb battery 7" past axle have same effect as more weight since kind of leverage against car lifting? If know how to figure the effect please do tell.

This message has been edited. Last edited by: wideopen231,

Ask Gemini or ChatGPT - the new LLMs are really good at math.

quote:

Originally posted by Brandon@BTE:
Ask Gemini or ChatGPT - the new LLMs are really good at math.

Thanks after running threw formula few different combo. Seems about 2:1 ratio of tq or effprt to lift it. Which I take it to mean the 45 acts like it is 90 lbs. If so gives bunch of chassis tunning combos fro where is to dbl effective weight with about 3 others between.

I have one more thing to check. Front has built in slip. Going to jack car up behind nose with it loose. measure how much lift vs wheel lift then move weight and measure. May or may not tell me anything. Will investigate tomorrow since 11 o clock and old a$$ has to do sleep crap sometime after 3 3AM bedtime nights.LOL

Dang. What I heard in my head is so more than enough weight and now know can run wire wheels which is huge weight loss, I think over 20 lbs total.Plus probably run aluminum spindles which has to to be 4 or 5 lbs. So for 1500 bucks can drop 24 to 25 lbs off car and few off butt because will not be able to afford food. LMAO

math done bit me in butt again.

Crazy drag racers...........

I think what he is asking here in original post is if you have a fuel cell and battery weight in the front and you move that weight forward some how much will it effect it? Maybe 95 Lbs 7 inches further forward?

The actual weight on front wheels may not change much but the further forward you move it harder it is to lift it. I am assuming he wants to move the weight forward to limit wheelies? Weight location is huge on a FED.

The last post was about removing 24 or 25 Lbs off the nose which would completely eliminate any benefits of moving the weight forward.

One other thing to think about is my FED liked the chassis stiff, a slip joint would have made my car worse. The thing is no two FED are the same. But if it is pulling the front wheels too much adding weight and or moving it forward will help. Removing weight up front will make it worse. Once again we are assuming you are moving weight forward to limit wheelies.

Quick note. Under full throttle there is very little weight on front wheels even at finish line. My car would not steer but by adding 20 Lbs made it drive like a Cadillac.

dIsagree.

If weight is haveing effect of being more than it is. Accoording to the math and it is just that and only that. Moving fuel cell almost zero effect since only up to axle. Moving battery has big effect. Raio is almost 2 to 1. So guessing 45 lb acts liuke its 90. In effect you added another 45 lbs. Agree? If that is true you could remove the 24 lbs at axle and have less real weight but chassis will still think it has lot more. If it thinks it has 45 more and you remove the 24 at axle it should at least think it hyas 21 more on it. Hopefully stated as to convey my point,not always my strong suit.

One side benifit should be I can remove weight while still having same effect on balance. Now that is win win if ever there was one.Alrerady removing 20 more at engine bay area with another idea I had and been wanting to do for while. Now have time to do. Will skip debate on that till done with it.

Now this is all just math and may differ in real world application. Will be month or so before I can test again due to cast on right foot in effort to keep toe attached and not cut off laying in hospital dumpster. yea giving me down time not good thing.Brain goes into what if mode and that always cost me.LOL

Just look at any fast JR fuel car or nostalgia class , motor is way forward full length glide or three speed ( some have a small driveshaft) battery and fuel forward too.
I’ve seen 40 lbs turn into almost a dime in et gain. Depends on what the car wants.

That is why enigne is 50" out on my car. Well thyat and Frank Parks said to do it that way.LOL

You know the old saying. In the air for show .On the ground for dough. Drives better that way too.

Perfect! He’s the guy!

I’ve been working with Rick Santos and he’s almost talked me into a fast FED TD!
God I miss my front engine days!!
But times a ticking here..

Is Santos going to build a SBC for a FED for you. If so it would be bad SOB. Heck lite wieght FED with Santos power should be easy ticket to fast TD. Now get a Parks car with his lite weight stuff and he has a ton and that combo would be rocket.

Do you have any timeslips or data to know if your're moving in the right direction on the car?

Few decent 60' times. Had a steering issue last few times dwon. Not weight related more fabricator f up. Was working on correcting that and found some info on rules that I can use to my advantage. that led me to thinking about how much I could move battery and then how much would it effect chassis.

So correcting front end steering got me to question physics of something that also led me to seeing how one can lead to removing actual weight off car w/o hurting balance. See not working due to need to keep weight off foot is costing me work and money.LOL

If you do not learn something new everyday you wasted a day of your life.If you do not question things you never learn a thing.Plus oncfe I have idea I am going to try it or bust hell wideopen.

I figure if can pick up 60' at all and car drives smooth I am going right way.If not Slide battery back,leave fuel cell up and hammer it. If new weight loss 9Not wheels and tires)does not break and kill me all will be good. LOL

what you are looking for is the "moment" that the weight causes at the centerline of the rear axle.

The Moment of a force is a measure of its tendency to cause a body to rotate about a specific point or axis. Moment = Force x Distance or M = (F)(d)

If you want to compare movement of some things that are different distances from your pivot point (rear axle) multiply the weight of said object vs. the distance from the pivot point. Whichever is the bigger number will result in more downward force or resistance to lifting the front end.

Now if you want to verify all of that go get 4 scales, move your fuel tank and battery then compare.

Using Triple Nickel's formula and making a wild assumption that your front and rear axles are exactly 15 feet apart, moving 45 pounds 7" forward of the front axle would have the same effect as leaving the weight on the axle but adding 1.75 pounds to it.

Roughly speaking, you moved the weight about 4% further from the rear axle and increased the effect of the weight by the same 4%.

Using that I moved the weight forward of front axle which would be where leverage is changed at since it is levarging off front acle when at rest. Yes rotation is at rear axle and using that. wouldn't total weight need to be part of clculations or ratio of battery to total wight? My front axle is 18.75' and battery is now 14" to center of mass from there. Not to mention chassis and my ass conter weight leveraging back down which would help in picking front end up. Just saying lots of parts to real answer. Car. weighs 1786 with me in it, 220 plus cage, seat chgute and wheelie bar are behind axle rest is infront of rear axle/ Incase figuring from rear axle.

Another point on the leverage thing. **** LaHaie said weight above rear end was dead weight, but weight behind rearend was weight transfer and why not make it work for you if carring it down the track.

I am thinking only way to know real change is to pick chassis up with some sort of scale reading how much more effort it takes to lift front to a pint lets say 3". Now where to pick it up at. My thinking is at front axle.Going to try next week or so when get scales.

I talked another FED racer that said he added 30 lbs to keep from lifting front end. HAd some work done and moved the weight foward 12" and then pulled wieght till lifted front end. He pulled 18 of the 30 off. Not back to back by any means.
I know another guys car moving engine 3/4" made same front axle weight as 20 lbs in front of axle. Nothing realy to compare to but example of how little makes big difference.

So basically getting different results that all show a little can be alot. Expecgted different replys.

This message has been edited. Last edited by: wideopen231,

Not saying Tripple Nickle is wrong about reading in scales. That would tell difference on wheels balance wise. Not sure that would tell what it takes to lift it when concidering the leverage effect. Kind of like examp0le I used in a physics class about race cars and physics.

Try to curl a weight in palm then move it back to behind wrist. You can curl more behind wrist because leverage is not working against you. Learned this in muscle and fitness. A short arm guy can curl more than long arm guy assuming same force generated by bicept.

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Side note. Is Kind of fun having debate on subject w/o bunch of name calling and insults. Thanks SL.

Damn now wondering what effect driver position behind rear axle has on whole thing. Not that I can change. Hey news max gets boring after while and trying to stay off the foot.

Yea I was that kid that asked questions, but he11 just wanted to know why it worked so can make better.LOL

Maybe ask o9n speed talk lots of engimanures and phusics guys there.

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