B4 advice

[mpg200]

I'm about to have another go at 2WD, Ive got a B4 and planning on using a 10.5T motor running indoors. Now in the past I have used a 20T brushed in it and had some quite pleasent race evenings at york when I found it rewarding do drive. But the last time I drove it, it was a nasty hateful endswappy beast with not respect for who has the controller, and we fell out big time. So, what is a recommended setup for indoors so me and my B4 can be friends again, also how tight should the diff be? I dug it out last night and found it to be very tight, surely this cant help?

Thanks

Matt

[kayce]

For starters, I think you're going to find that the 10.5 BL is just going to exaggerate the endswapping problem you noted, as it's going to be way more powerful than the 20T brushed you were used to. Just curious, but how large of an indoor venue are you going to be racing at that made you choose the 10.5, because most people agree that a 8.5 is the largest mill they'd consider in 2wd buggy on a large outdoor track ??

[peetbee]

Er Kayce, I think you've got it mixed up. A 10.5 is slower than an 8.5 (whilst admittedly being a bit more powerful than the 20T)
A 10.5 should be perfect indoors.

mpg200 - I would follow the instructions for setting the diff in the manual and see how tight it feels then.
What's your current setup on the car?

[kayce]

Originally Posted by peetbee

Er Kayce, I think you've got it mixed up. A 10.5 is slower than an 8.5 (whilst admittedly being a bit more powerful than the 20T)
A 10.5 should be perfect indoors.

I'm well aware a 10.5 is a wee bit slower than a 8.5, but just saying that a 10.5 is a LOT faster than a 20T brushed. And thus my query on how large an indoor facility he was running, since most are quite a bit smaller than most outdoor tracks were a 10.5 would be a more appropriate choice. The OP was already making reference that the car was a handfull with a slower motor, and your advice ("should be perfect indoors") seems to compound the common newbie problem of "over-motoring" their car, IMHO.

[mpg200]

Front:
35wt blue springs
rear:
30wt silver springs

yellow mini spikes do have pins also both were awful last time
about 25g for weight in the rear bulkhead
trailing steering arms
cant remember the shock positions of anti squat or wheelbase, i'll check tonight.

I'm too used to lazy 4wd go where you point it
But like i said it has been pleasent and rewarding in the past, and i dont remember changing much except when it was slippy i tighten the diff which made it worse, then i threw it up the corner of the shed and didnt talk to it for 6 months

Cheers
Matt

[Steven Forster]

Originally Posted by mpg200

Front:
35wt blue springs
rear:
30wt silver springs

yellow mini spikes do have pins also both were awful last time
about 25g for weight in the rear bulkhead
trailing steering arms
cant remember the shock positions of anti squat or wheelbase, i'll check tonight.

I'm too used to lazy 4wd go where you point it
But like i said it has been pleasent and rewarding in the past, and i dont remember changing much except when it was slippy i tighten the diff which made it worse, then i threw it up the corner of the shed and didnt talk to it for 6 months

Cheers
Matt

Have you checked the slipper clutch setting ???

[mpg200]

Kayce: The venue is a large ish indoor sports hall
http://www.youtube.com/watch?v=25ALnMPEsCE
I run 10.5T in my B44 no problem, some guys are running 6.5 but that thats just silly indoors. as a comparison my B44 rear diff feels a lot looser than the B4 so i think that may be where the problem lies. It was 6 months ago when me and my B4 fell out and I feel ive got much better since then.

Dexter: I'll have a look at the whole gearbox, strip and rebuild as per manual then start over

Bradders setup for worksop should be a good starting point

[kayce]

Originally Posted by mpg200

Kayce: The venue is a large ish indoor sports hall
http://www.youtube.com/watch?v=25ALnMPEsCE
I run 10.5T in my B44 no problem, some guys are running 6.5 but that thats just silly indoors. as a comparison my B44 rear diff feels a lot looser than the B4 so i think that may be where the problem lies. It was 6 months ago when me and my B4 fell out and I feel ive got much better since then.

Exactly my point, a smallish gymnasium type of set-up, complete with slippery sections, where a fast motor isn't needed. But I'm sure you know 2wd and 4wd's have different power demands, and power handling, capabilities. Realistically, IMHO, I think you'd find that on that size of a layout that even a 17.5 would be plenty, and a 13.5 would be way more than needed. Still can't see that you'd ever have enough straightaway to use a 10.5, but pick your poison as you're the only one that has to live with it. Good luck.

[peetbee]

Originally Posted by kayce

I'm well aware a 10.5 is a wee bit slower than a 8.5, but just saying that a 10.5 is a LOT faster than a 20T brushed. And thus my query on how large an indoor facility he was running, since most are quite a bit smaller than most outdoor tracks were a 10.5 would be a more appropriate choice. The OP was already making reference that the car was a handfull with a slower motor, and your advice ("should be perfect indoors") seems to compound the common newbie problem of "over-motoring" their car, IMHO.

apologies, misread your post, thought you were saying that 10.5 was slower, on re reading can see that wasn't the case.
However, we race in a smaller hall than that and a 10.5 is perfect in the B4, having run it for the last year or so (previously ran a 7.5 cos I couldn't be bothered to change it from outdoors!)
I started racing in 1982 so hope I'm not classed as a newbie anymore!

[peetbee]

Originally Posted by mpg200

then i threw it up the corner of the shed and didnt talk to it for 6 months

LOL!
The setup sounds good, if you're really struggling for rear grip then something I found that helped was an extra .5 degree rear toe in.
Part no 7487 rear suspension mounts - cheaper than hubs!
Are the top of the rear shocks on the innermost hole?
also try setting the spacers on the rear hub so you are running the longest wheelbase setting

[kayce]

Originally Posted by peetbee

apologies, misread your post, thought you were saying that 10.5 was slower, on re reading can see that wasn't the case.
However, we race in a smaller hall than that and a 10.5 is perfect in the B4, having run it for the last year or so (previously ran a 7.5 cos I couldn't be bothered to change it from outdoors!)
I started racing in 1982 so hope I'm not classed as a newbie anymore!

When the OP posted the car as "a nasty hateful endswappy beast," and considering how small a venue he's planning to run, your theory (especially applied to him) still doesn't hold much water. Please do explain your rationale.
I won't attest having your length of experience, but I would have thought you'd have learned against over-motoring decades ago.

[peetbee]

I guess that's where we differ, I see the issue with Matt's "nasty hateful endswappy beast" as being solved with the correct setup, for example by not having an overtight diff or by setting the slipper differently or by increasing the level of the rear grip available, rather than just slowing it right down until it doesn't swap ends.

However, there's a chance that we could both be right :

[mpg200]

Ok thanks for all the input guys, I’ve formulated a plan.
1. Leave the 20T Saturn in and sort out the diff and slipper, get back to being pleasant and rewarding again. (new mini pins will also help)
2. Then once we are friends again put a 10.5 in and turn down the EPA to something sensible.
3. As I get better at 2WD open up the EPA to release the power.
Thanks guys

Matt

[peetbee]

Sounds like a good plan

[kayce]

Originally Posted by mpg200

Ok thanks for all the input guys, I’ve formulated a plan.
1. Leave the 20T Saturn in and sort out the diff and slipper, get back to being pleasant and rewarding again. (new mini pins will also help)
2. Then once we are friends again put a 10.5 in and turn down the EPA to something sensible.
3. As I get better at 2WD open up the EPA to release the power.
Thanks guys

Matt

Good idea, at least that way you'll have a baseline of something more managable for comparison purposes when you do make the change over. All I was trying to point out was that, considering the slippery sections on your track coupled with the smallish size of the layout, I didn't really see that you would have room to use the power of the 10.5. I just see too many instances of guys with too much motor, and besides not being able to use what they have all they end up doing is buzzing the rear tires and increasing their tire bill. But turning the EPA back to about 70% (or maybe less) would tame it down to a more usable level. Have fun

[westie]

Originally Posted by mpg200

Front:
35wt blue springs
rear:
30wt silver springs

yellow mini spikes do have pins also both were awful last time
about 25g for weight in the rear bulkhead
trailing steering arms
cant remember the shock positions of anti squat or wheelbase, i'll check tonight.

I'm too used to lazy 4wd go where you point it
But like i said it has been pleasent and rewarding in the past, and i dont remember changing much except when it was slippy i tighten the diff which made it worse, then i threw it up the corner of the shed and didnt talk to it for 6 months

Cheers
Matt

sounds like a good setup to me, check your diff for tightness.

[Col]

Originally Posted by mpg200

Leave the 20T Saturn in

Puff.

Stick the 10 in. Most 2wd's are running around that at York.

I think this is a better clip to show size: http://www.youtube.com/watch?v=C2Am2...eature=related

Was one of my altime fav tracks!

(yes, I run a 6.5 in 4wd)

[mpg200]

I remember that track. It was great fun. I was running my cat 2000 that night and I did quite well for a 20T

[mpg200]

Ok so here is a report on how it went.
Me and my monkey (Alasdair) both decided to go for 2WD fun despite my earlier thoughts of leaving the 20T in, I threw caution to the wind and put a 10.5T in each car (both B4s). Results were surprising,
Me first:
1st heat, minipins. It took a few laps for my brain to adjust the lines to take and the breaking points. But OK it was fun.
2nd Heat: mini spikes MUCH better, still a bit twitchy on throttle.
3Rd Heat: Stick with the minispikes slacken the slipper and turn down the breaks. Loads better we are friends again.
Final: fell of the jump on first lap marshal didn’t see me for a while… race ruined, but hey once I got going it was fun.

Alasdair: (he’s 11) First time with 2WD
1st Heat: Faster laps than me but finished behind me, he was a getting used to it.
2nd Heat: minispikes, sorted now, getting faster,
3rd Heat: slacken the slipper a tiny amount, He made a sub 20second lap and gets in the top 10 fastest laps
Final: Qualified 4th Finished 3rd and was chasing Steven Butterfield hard.

Overall
So much better than my last 2wd nightmare, and I’m really proud of Alasdair he just got on with it, no fuss. Coming to a podium near you, soon.

[Steven Forster]

Originally Posted by mpg200

Me and my monkey (Alasdair)

...........quality