XB4 uk indoor setups?

[andys]

Anyone managed to get their XB4 running really well on uk indoor tracks - slippy floor / carpet etc?

Ran mine 3 times now and it's getting better but it still over rotates a touch and the back end feels loose. Can't push the car as hard as my 410 and running them back to back my lap times with the 410 were around 1sec a lap quicker.

Started with kit setup and now running the following changes.

Front - kit piston with 30wt
Rear - kit piston with 20wt

Rear - 4 degree toe - 2 degree anti squat (kit)

Running 2 x small strips of lead at sides of cells (this helped and I think I'll try more weight under each lipo next)

Front camber link on top hole.

All centre flex screws removed.

Car is much better like this - but I still want the rear to be more planted - not sure if altering anti squat would help - thinking ill just add the under lipo weight

Anyone got any 'top tips'

[atsang]

Currently on my 8th meeting on both polished wood and astro...

On polished wood im running the shocks as follows

Front - Middle on tower inside on arms 30wt (3 hole piston)

Rear - Middle on tower inside on arms 25wt (3 hole piston)

kit roll bars on both front and rear

front link short and up on tower

rear link long and down on tower

roll centre - outside hole on arms

rear inserts 0 all round

+.75 hubs on rear

10k front diff 5k rear diff

no limiters in the shocks (full droop)

Flex - Full flex no screws

dBoots nanobyte B compound with dBoots medium inserts

This is my current set up and it is quite aggressive where i have my D/R down to around 85% but works well on loose or low grip surfaces...

[andys]

Cheers astang

Pretty similar to me then.
What does the lower camber link on the rear give you?

Also - rear hubs, are they an option part ?
If so what's the rear toe you are running then ?

Cheers
Andy

[atsang]

Originally Posted by andys

Cheers astang

Pretty similar to me then.
What does the lower camber link on the rear give you?

Also - rear hubs, are they an option part ?
If so what's the rear toe you are running then ?

Cheers
Andy

Lowering the link allows the car to roll more in the rear so it means u are less likely to break traction where as when u raise the link then u are stiffening up the rear of the car and yea the hubs are an optional part just makes the rear wider and more settled and makes it feel like the rear has more grip... As for toe im guessin its 3 degrees of rear toe as the inserts im using are 0 all round and normally 3 degrees is standard...

[gwesty]

A lower rear link will give more initial grip , it will also transfer more weigh to the rear on acceleration allowing the car to square up earlier . Toe on the hub will add more tyre scrub . If your car is over rotating off power try a higher rear link or harder diff oil

[neallewis]

Andy, I discussed this topic with you sunday at Batley...
All the setups sheets are for either carpet or clay, not the indoor surfaces we run on in Yorkshire. I've only run once so far at Batley, once at York and once at Cullingworth. All slippy floor. I've improved mine, but it's still wanting to break away on the rear and rotate.

My last changes were:

Rear:
No rear anti roll bar, 25wt on kit 3 hole pistons, 1 dot (C=0.35) springs, lower shocks on the inner holes (This helped a lot at york both on crashmat bumps and rear end grip). Top link ball studs are lowest hole. diff oil 5000cst. -2deg camber, 4deg toe in with

chassis: no flex screws

Front:
kit antiroll bar, 35wt on kit 3 hole pistons, 2 mm limiters, progressive 2 stripe front springs. forward akerman holes on crank. everything else kit. 15000cst diff oil.


My next changes will be to run the 6deg C hubs left and right. kit (2 dot) front springs, and I want to run less anti squat on the rear. I may try the wider rear hexes too.

I've been running yellow mine spikes, but want to try minipins.



This might be of use:

Spring Chart
Front
Linear 1dot C=0.65 or 3.71lbs/inch
Linear 2 dot C=0.72 or 4.11lbs/inch
Progressive 2 stripes C=0.65-0.85 or 3.71-4.85lbs/inch

Rear
Linear 1dot C=0,35 or 1.99lbs/inch
Linear 2dot C=0,40 or 2.28lbs/inch
Linear 3dot C=0,45 or 2.57lbs/inch
Progressive 2 stripes C=0,35-0,45 or 1.99-2.57lbs/inch

[neallewis]

Originally Posted by gwesty

A lower rear link will give more initial grip , it will also transfer more weigh to the rear on acceleration allowing the car to square up earlier . Toe on the hub will add more tyre scrub . If your car is over rotating off power try a higher rear link or harder diff oil

It's over rotating on power.

Did you mean front or rear diff oil?

I've left my kit oil (5000cst) in the rear, and gone for 15000cst in the front. I think this has helped.
I did this as I'd heard that running lighter oils all round made the car not feel right. I'm new to tuning diff oils though.

[reg]

Take a look at the setups on petit,the worksop one sime46,it sound abit like what your run on,
still not tried mine yet but will be starting on it

[gwesty]

A harder / tighter rear diff will help stop over steer / rotation off power .

[neallewis]

Originally Posted by reg

Take a look at the setups on petit,the worksop one sime46,it sound abit like what your run on,
still not tried mine yet but will be starting on it

I did look, when it was out, but it was pretty much kit setup, other than lower roll centres, which i'll look at again.

[Pedros20]

I have to say Sime's car & setup was spot on this weekend at West Bridgeford.
He finished 3rd overall with some really good drivers there.
I was so impressed I went out & bought an XB4 after driving his car!
It was awesome!

[andys]

Originally Posted by Pedros20

I have to say Sime's car & setup was spot on this weekend at West Bridgeford.
He finished 3rd overall with some really good drivers there.
I was so impressed I went out & bought an XB4 after driving his car!
It was awesome!

Had a look at the setup sheet and I don't understand it - I think it's wrong re the values for rear toe

Looking at the manual and the setup sheet - the car is running running 2 degrees rear toe - not 4 as on the setup sheet?
Looks like he is running 3 degree anti squat - kit is 2?

Front bushing placement makes no sense to me either ?
Manual shows 3 positions for track width, and how it's set, - +1.5 at front and -1.5 at front/rear seems a bit odd and pointless as effectively you may as well run kit 0 front and 0 front/rear when using the centre height position to get the same track width.

Confused !!!!

[Pedros20]

Not looked on Petit, I'll have a word with him, see if he can clarify what he's put is actually what he's running.
But when I build mine I shall be building it the same as his.

[brooksy]

How different to the zx-5 do you think it is Pete?(having only a few laps with it).
I'm thinking of getting one eventually,hopefully for the outdoor season.

[andys]

Originally Posted by Pedros20

Not looked on Petit, I'll have a word with him, see if he can clarify what he's put is actually what he's running.
But when I build mine I shall be building it the same as his.

Cheers fella - those eccentric bushings are quite confusing, took me a while to figure it all out

I know i'm running 4 degree rear toe, and that did seem to help.

It's tricky to get your head around it all though, for example if you wanted to run widest rear track / width, you then can only go the the max kit setting of 3 degrees rear toe as you are putting the wishbones to the widest position and to get more toe, you have to pull them back in using the rear/front bushings.....

[andys]

Had a few very helpfull messages / emails from Sime.

Basically the setup sheet has gone wrong with the dots !

Rear he's running 3 degree (kit toe) but high roll centre.
Front - again kit but wide track (+1.5)

Makes much more sense and I'm hopeful it will lock the back end in.
Hudy setup book says high roll centre at rear =

More on power traction
Use to avoid traction rolling at corner entry
Use in low grip conditions

So - fingers crossed.

I also re filled the rear diff with 10k - surprisingly it was empty - no oil after just 3 meeting.

[reg]

Glad you got it sorted,hope it goes well,keep us posted

[neallewis]

Originally Posted by andys

Had a few very helpfull messages / emails from Sime.

Basically the setup sheet has gone wrong with the dots !

Rear he's running 3 degree (kit toe) but high roll centre.
Front - again kit but wide track (+1.5)

so where are the dots meant to be on the sheet? I take it you mean the lower arm roll centre, not the upper link roll centre?
so he's used the inserts to widen the front track? adding the 1 insert in outer location ff and fr?
How does widening the front track help lock in the rear?
I was going to get the wide Hexes to widen the rear track.

Originally Posted by andys

Makes much more sense and I'm hopeful it will lock the back end in.
Hudy setup book says high roll centre at rear =

More on power traction
Use to avoid traction rolling at corner entry
Use in low grip conditions

So - fingers crossed.

I also re filled the rear diff with 10k - surprisingly it was empty - no oil after just 3 meeting.

My front diff was almost empty as well, when I checked. American forums recon its being absorbed by the composite gears ;-) I'd say it was leaving through the outdrives.

Why have you got to 10k on rear? what's the thinking behind it?

cheers

[sime46]

Sorry. Not had chance to amend my setup sheet. Basically this is how I'm running mine right now. It locked in the rear end which had been a little free and easy. Sorry for the poor quality. Ill get a proper sheet up ASAP. As said prior, it's wide track front(takes a little grip away from the front and high rear pin which improves rear stability and traction loads. Give it a go. It's an easy thing to adjust.

[sime46]

10k in the rear diff sounds very thick. I'm 10k front/5k rear. I'm gonna try 5k/2k at Worksop during the day just to see how it feels with significantly lighter oils on that surface.