b4 and lipo , weight ?

charles08 · #1 09-03-2009

Hi.
I am racing lipos next week end for the first time and won't have much time to practice since then .
So i am wondering if you guys can help me on where i should put the weights in the car knowing that the lipos i 'll run are 260 gr ( Corally 4200 30c).
I don't have the heavier front bulkhead and i'll race it on carpet .

Thanks to all !

Mike Hudson · #2 09-03-2009

standard nimh cells weigh around 450-470g so when you use lipo you need to add a fair bit seen as your losing around 200g! Get some thin roofing lead if you can (quite a few people on this forum have plenty to sell at low prices if you don't know where to get any and cut out a rectangle the same length and width as your lipo (you can cut it with scissors easily!) and put it underneath the lipo and all should be ok, maybe drop a spring rate front and rear on the car aswell

charles08 · #3 09-03-2009

Thanks mike !

I thought it was going to be something like adding 30 gr on top of the servo, 50 on the battery tray etc ...

Your solution looks very simple, i'll find some lead and cut it to get the 200gr back and put it underneath the lipo then.

Thanks again , cheers .

Mike Hudson · #4 10-03-2009

you won't get the full 200g back you'll only gain about 100g max but it's ok just drop down to a softer spring on the rear and maybe drop down to a softer spring on the front too or lighter oil and it should be ok,

V-Rossi · #5 10-03-2009

I fitted a lead plate under the battery of around 110gr and the car was planted with the standard Associated astroturf and carpet set-up.

Zipper · #6 10-03-2009

This is the latest set-up from the Associated website for a B4 running LiPo. I know they are trying to prefect a LiPo set-up without the need for adding lead. Maybe an ok starting point?

http://67.199.85.166/racing/setups/b...crcrc_2009.pdf

Mike Hudson · #7 10-03-2009

without adding weight the car is under the legal brca weight though

and that setup is for american dirt tracks so may not work so well here

Zipper · #8 10-03-2009

I ran almost the same set-up at the Petit RC (carpet), just with lead running down each side of the battery tray to get to the legal weight and blue front springs and was very happy with how the car performed.

charles08 · #9 10-03-2009

Thanks guys for all the infos,

I'll try that setup on a training day, but black springs/rear on a carpet track that must feel kinda weird ?...

Zipper · #10 10-03-2009

oh yeah... I also ran silver springs on the rear!

zaquiz · #11 11-03-2009

Quote:

Originally Posted by V-Rossi

I fitted a lead plate under the battery of around 110gr and the car was planted with the standard Associated astroturf and carpet set-up.

Where can I find lead plates that fit the B4 & B44?

RudeTony · #12 24-03-2009

Have a look at this!! - Made from Brass and has exact 60g weight. Perfect and no nasty weights showing everywhere - Also your name can be put on it. Cheap enough as well. David Burton former National winner and an engineer by trade makes them to order - 5 days and they can be with you. Anyone wanting one, let me know and I can arrange for you.....

Lee Martin · #13 24-03-2009

nice work DB, could your name not be cut out though? rather than stamped?

russmini · #14 24-03-2009

But then you'd Lose Weight....

Lee Martin · #15 24-03-2009

not a great deal though! and would look wayyyy cooler....or groove the name using a lathe etc?

RudeTony · #16 24-03-2009

Hi all - the name is engraved on the brass - it can also be cut out if you wish - in fact anything is possible. Some people even like logos etc etc....Brass is expensive as some of you may know and this unfortunately reflects in the price a little - the brace is £12 (plain) and £2 for your name - obviously plus a little for shipping - if you think about it, the weights are some £4-£5 alone! - Good luck with everyones racing by the way - Tony

RudeTony · #17 24-03-2009

Added another few pics to show the engraving and the thickness - hope this helps you.....

RudeTony · #18 31-03-2009

PM send to those relevant

Chris Green · #19 31-03-2009

I've put a sheet of stainless steel underneath my Lipo. My Complete B4 now weighs in at 1581g?

Is that too heavy?

without the stainless steel sheet, it is 1430g ish? what is the ideal weight?

Mike Hudson · #20 31-03-2009

for brca events legal minimum weight is 1474g (mine is around 1530g with minipins, minispikes are a little lighter) with 50g added around the front and rear of the car, run what weight you like, it's more down to how you like the car the to feel, less weight it's more agile and on the edge but with more weight it calms it down abit and keeps the car planted and abit easier to drive/more predictable