BigBuckORamma

Same part numbers at the B6.4

91983 - Bellcranks
91984 - Steering Rack

Be careful, on dirt/clay the aluminum steering rack makes the car very nervous in uneven surfaces.

MrLean

iTrader: (17)

It also appears hes running 1.9 front pistons with 37 weight oil...pretty genius how he writes it right on the chassis, I've never seen that.

andrewcoley

i’m going to start writing piston/oil on my lipo weight. Less visible and easy to clean off 👍 Will please my OCD tendencies more too 😂

I might even write it on the underside of it!

andrewcoley

Our indoor carpet season is done at my local club, 1066 Racing, Overall I really like the B7, it’s a weapon. Boring debrief for you all:

I haven’t quite got the B7 as dialled as my 6.2 was, but that had the short chassis and all the many carpet specific mods developed over the years of the B6 range.

I’ve only broken one ball cup, and I’ve crashed heavily a fair few times 😂 Seen plenty of people do the idler gears, but nothing else on the car is a major worry to me. Will probably go aftermarket for those next indoor season.

Due to work schedules I’ve only had 3 club meetings and a BRCA regional with the car so I’m not too concerned it’s not bang on yet, haven’t had it long enough.

Last club night I won both legs of the B final, the regional I qualified 15th from 40 then had awful finals, just the way it goes sometimes! A little ahead of where I felt I'd be with the 6.2 in terms of results.

Outdoor season incoming, bought a B74.2CE and I’m excited to build it. Our club has worked super hard this winter and we’ve found the funds to go astroturf instead of grass outdoors, so hopefully no more Thursday night mowing parties 😂

On a side note, saw all the Willspeed parts for the car at the regional, as always really nice stuff, will deffo be getting some. Heard a rumour they’ll be doing idler gears and some other very interesting stuff soon 😉

AmiSMB

There is also another shot showing he used 2mm holes with 30w for the rear too
https://site.petitrc.com/setup/assoc...4/RW104607.jpg

Piles

….and 2.0 with 30wt in the rear.
Im on exactly the same on bumpy astro and its very good.

RogerM

I don't know the mass of the Willspeed bulkhead but ideally you would want to keep the mass as centred as possible to keep the car agile, especially in fast direction changes. That said a little additional mass in the front can help numb the reaction of a twitchy car and pick up a bit of mid corner steering.


Absolutely. We have tried adding a little weight to the front but most have agreed that about 15g extra in line with the front axle is about the most you would want outdoors (maybe a little more id possible on carpet)




Tungsten putty is a good shout for tuning, you can put around 15g in the front bulkhead and there is room for about 5g either side of the servo mount.


That is a prototype steel bulkhead on Neil's car, several others had them too, I am expecting them to be available on the CENTRO brand soon. They weigh 14g more than the kit aluminium bulkhead.
Steering rack is lower as he is using a low front axle height and a reasonable amount of total castor and it is always preferable to lower the rack than use lots of spacers under the outboard ball stud due to the way the forces transfer through the steering tie rod to the chassis.

As a collective we have been trying to build setups without lots of additional weight in the front of the car to preserve the primary benefit of the B7, the fact that it carries fantastic corner speed.
It does seem like we are having to move towards adding weight around the front though as the Schumacher tyres seem to demand it. Remember what I have always said about not being able to substitute static vertical loading with geometry changes and that setup being all about giving the specific tyre what it needs .... well yeah, sadly we seem to be stuck with the LP cut stagger for a while longer :'(

drumondo

I've been struggling for acceleration and top speed with my B7, suggestions seem to be that this is the case due to the extra friction with the 5-gear transmission. Running in 17.5T stock with 33/72 gearing. Pulling the pinion tooth count back to 30 didn't seem to make much of a difference in punch, and had the downside of being even slower down the long back straight at my local track. Focussing on corner speed got me down to a 30.3 second lap at my local track, I really need to get into the 29's to be in the game with the fastest guys running 28's as hot laps.

I've pulled my motor timing back from 55 to 42, hoping to gain some torque to overcome the friction and gone back to the 33T pinion and will test again later this week.

Any other suggestions?

Alexv2024

iTrader: (2)

Why the huge swings in pinion size? Try a 32t or 31t pinion. Lower timing is what you needed, and maybe lower drive frequency on the esc. Maybe try a trinity thin aluminum pinion or the polypro or similar plastic pinion. Maybe a slipper eliminator.

Personally I'm going to get some narrowed cut gears (or maybe cut them myself I have a lathe now) and some ceramic bearings for my stock build. Yeah the 5 gear has more drive line drag but its not THAT bad.

drumondo

It's what I had on hand and my local store didn't have anything between 30 and 33.

I've pulled back the drive frequency, hasn't really given me what I needed. Timing seems like the last game in town (before I pull apart the transmission and rebuild), will test this afternoon.

elnitro

iTrader: (1)

So I've decided to run this instead of the Mugen. Unfortunately, kits are nowhere to be found especially the dirt version. Any leads in the US? Thanks

brian cox

iTrader: (90)

Hobbytown Hobbyplex in Omaha, NE Had one on the shelf this weekend

Alexv2024

iTrader: (2)

Ironically I bet Hoosier RC hobbyplex in Indiana also has some for sale. They usually have a big stock of everything as its quite a big hobby store and a big track.

Biz73

iTrader: (24)

NIB B7D

dr_hfuhuhurr

iTrader: (95)

RCMadness had some in stock (shows on the site as in-stock still) https://rcmadness.com/product/rc10b7-team-kit/