4x100 BG/BA hub brake upgrades

[GTXWGN]

hey guys

i have a question regaridng the 5 stud conversions and keeping 4x100 studs etc. i made this thread after reading the 5 stud conversion thread but decided id make a new thread to keep it on topic.

heres the scenario

say i wanted to go to 4x100 on my mazda wagon (which i am ) i have currently BF mazda hubs in 4x114.3 with the same spline as the BG/BA axles(custom made) , i run 266mm vr4 24mm slotted rotors and the v22 14 calipers from a BG astina with bendix pads..

now i was looking at getting the BG complete hub assembly from any bg in the 4x100 , i dont care wat size discs it has etc and mounts as i was going to make adapters to fix XX calipers( series 4 rx7 or 2 pot somethings).

i was going to swap complete shocks and use the BF tops on the bg struts etc for better handling aswell.

now what i dont get is why all this fuss over the v6 hubs and calipers, how come none of you havent just gotten the v6 discs and redrilled them to 4x100 or another cars larger rotor, and made custom brackets for whatever caliper you want (such as the 2 pot subaru ones mentioned? surely these sort of brakets are not hard to make up by any sort of fabricator..and u can keep the 4x100 hubs as i know v6 astina ones are hard to source , you can also go to a larger disc of say 300+

now i realise some of you want the 5 studs, but this aside wouldnt this be a better way to go for those wanting 4 stud. i know u can get the 5 stud v6 hubs and fit the 4x100 centres/bearings to get the result.

i have been thinking myself i could get the v6 front setup with struts and just fit the bg 4x100 centres to them and use these, however i want larger calipers aswell for track racing etc , so wouldnt the sohc BG $20 a side from any wrecker hubs assembly be the go?

also the offset of the rx7 caliper hitting the rims , couldnt u just get a disc with an offest making the disc further in making the centreline in further allowing u to custom mount the rx7 calipers ok?

sorry about all the questions etc and i hope its not too off topic but i just saw a few holes in the way some things were being done and was wondering if theres a reason

[GTXWGN]

just a little update after going thru the DBA catalog.

i have found the specs on the stock BG/BA 4x100 hub assembly to be

257mm rotor - 45.5mm offset on disc hat, 22mm thick rotor , 55mm centre hole

now i have found what would appear to be a direct fit with no drilling in the following (all 4x100 of various cars) the only issue is the centre hole is larger on all except the sportivo. the offsets arent a huge problem if u are making custom brackets , they are all deeper than stock which helps caliper clearance too. note redrilled v6 274 rotors have a 72mm hole anyway. the hole is used to centre the disc on the hub/knockle.

possible rotors -mostly available in slotted only.

honda euro V6 - 282mm rotor, 47mm offset, 28mm thick, 64mm centre DBA2514

honda legend 1987-91 - 282mm rotor, 51mm offest, 21mm thick, 64 centre DBA185

prelude Vtec - 282mm rotor, 47 offset, 23mm thick, 64 centre DBA200 - available in all models of DBA discs

2003 sportivo ZZE123 - 275mm rotor, 50mm offset, 25mm thick, 55 centre DBA759

mazda mx5 - 270mm rotor, 46mm offset, 22mm thick, 74? centre

of course u can redrill almost any disc to suit , however it looks to me , for someone after a 4x100 disc with no mods , with the right centre hole and all the rest, the sportivo disc is great and 25mm thick aswell, plus the 50 offset makes the rotor a few mm in further aswell for clearance.... otherwise for a filthy thick 28mm rotor the accord euro v6 seems to be a winner , i also found some kia models with mazda running gear also have 2 pot calipers that could be used with custom brackets...

any thoughts on these ideas?

[chicaboo]

Ross: Are you only after a front brake upgrade? As the puny 222mm rears on my KE Turbo bug the nuts off me. I would like a complete upgrade, so if you ran BG SP rears in 4x100 with the Sportivo fronts on BG SP hubs, you might be onto a winner. :)

Check your PMs! :p
Gav.

[project.r.racing]

i'd be looking at mx5 rotors, someone already has these fitted to a astina using FC3S front calipers. but you could prolly use the original 22V calipers with a simple mod.

other option is rav4 rotors with R33 calipers. both fit perfectly together and only need adaptor for calipers. dude here on sunshine coast does them for various cars.

ryan

[bourbon]

hmmm...i wanna look at larger brakes...as now ive got plenty of room to do it :p hahaha but dont want to goto 5stud now...

[GTXWGN]

thanks for the imput , the raav 4 discs are exactly the same as the sportivo but 5 stud and larger centre so it would be pointless to use them over them, however i think u can basically use any disc u want by the looks, at this stage for ease i think ill use the 4x100 sportivo slotted disc, and if for some reason 25mm is too wide for the larger calipers ill go to the 282mm/23mm prelude disc which u can get in the 4000 series aswell.

does anyone know how wide the discs can be in the rx7 calipers? i know they are 22mm stock on the rx7 but anyone tried it?


the vr4 24mm discs work with stock v22 14's

[project.r.racing]

thanks for the imput , the raav 4 discs are exactly the same as the sportivo but 5 stud and larger centre so it would be pointless to use them over themum? buy them undrilled and drill 4x100 holes into the rotors.

but if are the same, then just use sportivo rotors with R33 calipers.

the vr4 24mm discs work with stock v22 14'syes they do - as my rotors are 24mm wide also.

ryan

[project.r.racing]

i have been thinking myself i could get the v6 front setup with struts and just fit the bg 4x100 centres to them and use these, however i want larger calipers aswell for track racing etcdone before also.

so wouldnt the sohc BG $20 a side from any wrecker hubs assembly be the go?
smallers brake on SOHC.

[GTXWGN]

has anyone had a problem changing to 4 pots or 2 pots from stock and not chaning anything else and effecting the brake bias
does it make the rear lock up earlier than the front ?

reason is my car has all the brake bias built into the stupid master cylinder so i cant really change any of that , if its an issue ill have to look into something else for calipers..

[GTXWGN]

done before also.

smallers brake on SOHC.


yeah cheers i realise that , but it wouldnt matter if u were changing to larger discs and making caliper brackets would it? it would prolly be easier to make the brackets off the sohc hub as u would have more room to play with

[project.r.racing]

true i think???
but the sohc hub assembly my actually be smaller and that might (dunno if will) cause some issues. as the caliper bolts are in different spots that 22V bolts.
but will plates etc being used, prolly wont be an issue???

[jaimo99]

HI i got a BA Hardtop i was reading and you sound like you know a bit so i was just wondering....

What car are the 2 pot suburu callipers off ? and would these just bolt straight on to my brackets. Using original disk rotors.???

Thanks

[Cosmo Dude]

There are two types of Subie twin spot calipers, a 1 bolt type and a two bolt type. The ones I have are the one bolt type and are off a '92-'94 WRX and are also found on various Liberty/Legacy models.
They fit straight onto GD 626 brackets which bolt straigt onto the V6 Astina hub. The GD disk is 264mm diameter with a 64mm center hole and the V6 Astina disk is 274mm diameter with a 72mm center hole. The bracket doesn't fit over the disk (close but no cigar). Next trick is to buy some GD slotted rotors and have the center hole enlarged to fit the Astina before I try again. This will have to wait as it's too far from pay day and it's been an expensive month.

[RedLineResident]

cosmo that sounds to be the go, let us know of the benefits when its all done. I may just be interested in following in your steps later down the track.

[GTXWGN]

well all i can say is nothing beats getting the parts and trying!

i have some sohc 4x100 BG hub assemblies on my car now , it actually bolts on all perfect using the BG tie rod end , and a slot in the shock hole as they are slightly close together otherwise its a direct fit which is great , however i have some s4 rx7 calipers and theres no way in hell they are going to bolt up , theres no room for any brackets at all sohc or dohc or whatever the bolt holes on the calipers are just right in the way of the actual hub body and it fouls miserably and i wont fit 15's on the car either as it would hit the spoke.

i can however make an educated guess that if u had the sohc 4x100 hubs and say some 330mm discs then it would all fit and not foul if u had 17's , however i have to have 15's for the strip.

so there ya go , i have basically found im going to have to buy the 5 stud astina hubs and use the 4x100 centres on them , and do the subaru caliper and 265mm disc as you nice fellows have found .

thanks for all your help....

one last question , does the BA astina have different shock mounting bolt holes? or do they bolt onto the 1.8 struts ok? and if not why - are they thicker or just hole spacing?

and cosmo, u are using the GD disc as it i also 5 stud correct? do u think for 4 stud a 4x100 mx5 270mm rotor will fit? i know 274 wont but would it scrape in ?

cheers

[Cosmo Dude]

There is no reason someone couldn't use everything as I am with the exception of putting a 4x100 hub into the V6 knuckle and having the disk drilled to suit 4x100 ;)

[GTXWGN]

exactly , reason i ask about the mx5 270mm rotor is it is already 4x100 and has the 55mm centre like the 4x100 does. its a direct fit. its only 22mm tho not 24mm how much difference does that really make?

[Cosmo Dude]

The thicker disk will absorb heat more evenly. The pads will only contact as far as 264mm anyway so there is no need to go bigger.

[ROB-80E]

however i have some s4 rx7 calipers and theres no way in hell they are going to bolt up , theres no room for any brackets at all sohc or dohc or whatever the bolt holes on the calipers are just right in the way of the actual hub body and it fouls miserably and i wont fit 15's on the car either as it would hit the spoke.
http://img247.imageshack.us/my.php?image=dcp27842qb.jpg
I could have told you that...I had already tried it. However, you have more chance of making it work with a SOHC stub, compared to a DOHC one. However, i have read a few times that the RX7 caliper is a diret bolt up to the mounts on a GTR stub axel which is the same mounts on a BA V6 stub. There are a few pics floating around of the RX7 caliper being fitted to a GTX with custom brakets. You are still never going to fix the issue of how wide these calipers are, thus it'll be a major issue with wheel offsets and size. Engineering nightmare, as most of the mods required to make them fit will be illegal (street use) as you will have to change the track width of the vehicle.

The other thing with mentioned above is, why would you downsize your rotor diameter to fit the subaru calipers? The V6 rotors are bigger. Why dont you just use the whole BA v6 setup, change the hub and rotor and bob's ya uncle. Or is two spot calipers that important?
http://img64.imageshack.us/img64/2957/dcp30713px.jpg

[bourbon]

because he wants to stay 4 stud...i want to stay 4 stud now that ive found the rims i have and i dont want to change them...not everyone wants to goto 5stud...

[ROB-80E]

Huh? Was that answering for Ross in reference to my question?


If it was....did you look at the pic? BA v6 stub axel, calipers, 4 stud hub and rotor.

[bourbon]

you said why dont you swap over to the whole ba v6 assembly meaning 5 stud...

[ROB-80E]

Why dont you just use the whole BA v6 setup, change the hub and rotor and bob's ya uncle.
....

[bourbon]

i read it differently...

[Cosmo Dude]

The other thing with mentioned above is, why would you downsize your rotor diameter to fit the subaru calipers? The V6 rotors are bigger. Why dont you just use the whole BA v6 setup, change the hub and rotor and bob's ya uncle. Or is two spot calipers that important?


It's only when I assembled the calipers on the bracket and put them on the car that I found that the rotor was too big for them. As yet I havn't invested in rotors or pads. I have to compare the benefits of 2mm thicker, 10mm smaller diameter disks with twin piston calipers over the standard BA brakes.
So far I've invested a lot of time into this project and the GD rotors and pads will be cheaper than BA rotors alone.

[GTXWGN]

thanks for the imput , basically after all my mucking around , i have found the best thing to do exactly wat rob has done, i should have just asked him myself , i knew he had done it , i jsut wanted to see what i could fiddle around with its just how we do it haha..

anyway, the v6 rotors are a joke for a redrill when u can go the mx5 270 and they are a direct fit and have the 55mm centre hole , and as rob confirmed the pads still use all the disc with no overlap...

like u said the 2mm thicker disc might help a bit but im willing to sacrifice that.

i have already lined up and picking up this week 2 ba 5 stud hubs , while im there im going to go thru the caliper bin at mazda and see if there are any factory 2 pot calipers and compare them to the stock BA v6 , if all else fails im going to just use a complete stock ba v6 hub and caliper with the the 4x100 centre and mx5 discs like rob!..

i still have one unanswered query if someone could help.

are the shock mounts the same for the 4x100 and ba v6 where it bolts to the shock IE the 2 hole spacing and width of the knuckle bracket/support?

cheers again for the help,

as for the rears , im just redrilling the discs to 4x100 the disc themselves have the studs in them simple as. i looked at the astina 4x100 rears but i really cant be assed for a slightly large solid rotor with the same calipers

[Cosmo Dude]

u can go the mx5 270 and they are a direct fit and have the 55mm centre hole , and as rob confirmed the pads still use all the disc with no overlap...
What a load of crap! I have a V6 with the 274mm disks

like u said the 2mm thicker disc might help a bit but im willing to sacrifice that.
Your choice

as for the rears , im just redrilling the discs to 4x100 the disc themselves have the studs in them simple as. i looked at the astina 4x100 rears but i really cant be assed for a slightly large solid rotor with the same calipers
The BA V6 rear disks are identical to the I4 and NA Mx-5 rear, except that they are drilled for

[GTXWGN]

What a load of crap! I have a V6 with the 274mm disks


Your choice


The BA V6 rear disks are identical to the I4 and NA Mx-5 rear, except that they are drilled for

im not sure where youre coming from ? or did i insult u? its not a load of crap basically all i have said is that the 270 mx5 disc is the same as the v6 disc and doesnt need redrilling and is 2mm shorter around the edge but the pad still covers it, it also has the 55mm hole the 4x100 has not 72mm like the v6 , so u dont need a spacer made up , also as u pointed out earlier yourself, theres no point having a larger disc if the pads are in the same spot , so the 270mm disc isnt going to make the package any worse off at all compared to your 274 disc... , thats my load of crap there my friend , im glad you have the 274mm disc and good for you but the 270mm mx5 disc works a treat and is less work to use when keeping 4x100 , obviously if u are 5 stud you would keep the v6 disc,before i would redrill the v6 disc tho i would find a 24-25mm disc near 274mm and redrill and use that

i didnt get your point there sorry.

as for the rear my BF hubs are a hub type disc in 4x114.3 with a small as diameter, i dont have any BA hubs to use etc. , they dont slot over the stub/studs like the rest of yours do , the disc is part of the actual hub with the studs...its severly gay and the trailing arm bolts to the shock not the knuckle....., so im leaving my BF spec 4x114.3 rears alone but redrilling them to 4x100 if that makes sense . i can understand what i wrote might have sounded like i was trying to use BA ones



can anyone confirm the front hub strut bolt holes 5 vs 4 stud? EG - do u have to change struts in the front to go 5 stud BA brakes




Ross

[project.r.racing]

they dont slot over the stub/studs like the rest of yours do , the disc is part of the actual hub with the studs...its severly gay and the trailing arm bolts to the shock not the knuckle....., so im leaving my BF spec 4x114.3 rears alone but redrilling them to 4x100 if that makes sense . i can understand what i wrote might have sounded like i was trying to use BA ones

can anyone confirm the front hub strut bolt holes 5 vs 4 stud? EG - do u have to change struts in the front to go 5 stud BA brakesum? rear brakes are same as any maxzda/ford setup in that era. suggest you go look at a set.

2nd Q - change from what struts? BF? BG? BA? BJ?

Ryan

[ROB-80E]

Rosco, the BA hubs are a direct bolt on in all sence of the words. So no mods required to the strut bottom. HOWEVER!!! when you get the v6 stub axel, make sure you get the ball joints on the bottom too. The ball joints aren't interchangeable to the stub axel, but the BA V6 ball joint lines up with the BG control arm. Tie rod end is the same.

One other thing to try with the rears is see if you can bolt on a BG rear hub. Just undo the center nut and the hub slides off...I put BA rear stub axels on my car and used the BG 4 stud hub. Again, simply interchangeable. Might work with the rears on your car too...as the front wheel bearings are the same throughout the range.

Cosmo...as for your absolute crap...would you like close up pictures? Would you like to see the original BA V6 rotor that i pulled off and see the outer egde of the rotor where there is NO pad ware. IE, it's just a rusted edge where the pad has never touched close to the outer 2mm of the rotor. Meaning that when I fitted my 270mm rotor, the pad goes all the way to the edge of the rotor, but has no overlap. Ask for a pic and I'll go take one to prove it...it's that simple.

[GTXWGN]

well that sums it all up - cheers guys!

rob as for the rears , i think i could swap the entire hub over i think but id need BG rear shocks , i can try the disc section alone like u said however the caliper backet wont reach anymore sorta like fitting 257mm discs on a sohc front hub, unless i make brackets for the rears?

ps - why did u go to the BA rears are the rear discs larger aswell?

[Cosmo Dude]

OK,
The V6 pads go to the very edge of the V6 disk. If the radius of the disk is 2mm smaller then the outside of the pads will over shoot the disk. The little left over will probably break away harmlessly but that will lap over the disk. So there will be overlap regardless.

Rob has critisised my plan to use the smaller 264mm GD disks in place of the 274mm BA disks, he then suggests the 270mm Mx-5 disks. Isn't that a little hypocritical? Any way it's your decision to make.

[GTXWGN]

rob is running the 270 and the pad doesnt overlap , maybe a different brand of pad who knows.

[jaimo99]

what is an easy front brake upgrade with an Astina BA Hardtop (4 stud) The suburu brakes only bolt onto the V6 bracket/hub ??? right or wrong So the 1.8ltr BA front wheel hub has a different gap between the threaded mounting holes ???? what is the problem with fitting the
V6 Hub/bracket to the 1.8ltr if it all lines up?????????????? ill be back Mon

[Cosmo Dude]

rob is running the 270 and the pad doesnt overlap , maybe a different brand of pad who knows.

Be sure!