BUGA Community
Technical => Driveline => Topic started by: vuuup on July 29, 2014, 04:12:42 PM
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hi all, looking for some help with my DUAL WHEEL LWB beddy. finally tackling the gearbox and diff but have issues with finding parts for the diff and getting a bit lost in ratios. have tried searching lots of posts but unable to find specific info on my set up.
my main problem at the moment is that have opened the diff to find out that all tho is has a chev 12 bolt center the axel splines remain bedford, trying to install a lsd but my diff guy is having trouble finding parts to fit the splines. anyone had experience working this one out? and yes i really want a lsd as i am on dirt and muddy roads a bit with a heavy long wheel base.
also anyone got any recommendations for this next job??
my set up: 186 holden red engine with performance head, aussie 4 speed m22 gearbox, chev 12 bolt 3.55 diff with bedford duel wheel hubs, tyres 195 R 14 C 106/104N
issue with set up: 1st gear has not much power (engine may need some fine tuning) and 4th revs to high on the highway.
new set up: toyota 5 speed (will find out model on thursday), diff 3.08 or 3.23 or stick with the 3.55 and putting in lsd, may put larger tyres on??
old m22 ratios:
1st 3.74:1
2nd 2.68:1
3rd 1.68:1
4th 1:1,
rev 3.74:1
toyota box:
1st 3.954:1 to 3.285:1 depending on model
5th 0.85:1 to 0.78:1 depending on model
probably work perfect with old 3.55 diff and tyres????
any help or recommendation would be greatly appreciated. i am having a talk with my drive line expert on thursday but some bedford specific info may save a lot of $$$
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if anyone has a similar set up can you please tell me how 1st gear is like for hill take offs and what revs 5th gear is at 100-120ks
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Hi Vannup,
Best place for ring gear etc is the usa-google chev 12 bolt gears. Lots of ratio options, but I have a 12 bolt 3.55:1 in mine with a 186 and trimatic, so 1:1 top.
I have done a spreadsheet on this. Bit of an excel wiz. If anybody wants a copy, pm me with an email address. Or is there a way to add to the site??
Now it depends on your tyre size- I have 195R14’s, which have a circumference of 213 mm….. the rest is easy- NOT. Answer is 1744.9 rpm = 60km/h (compared to my old diff of 2189) in top
This makes your current first gear do approx. 10 km/h per 1000 rpm and the new….. about 150 rpm extra/less per 10 km/h, depending on the gears
0.85 gear will give 2471 rpm @ 100 km/h - using my tyre size
0.78 will be 2268 rpm @ 100 - using my tyre size
I was looking at this as I was thinking of putting in a T700….. top is .6967 that would give me 2026 rpm @ 100, and I wonder if the engine would happily pull that load. After all, we are talking nearly 2000 kg. Any other thoughts?
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WOW!!! thank you rumax. great info in one post! will pm you my email if you can send that spreadsheet through that would be great.
from what you have said i will probable stay with the 3.55:1 ratio depending on which toyota gearbox i can get, and always have the option to change tyre sizes later.
not to sure about the t700 as have not seen one in a bedford
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if you get a celica box I'd highly recommend the 3.28 1st gear!
I've attached a few spreadsheets I've made in the past, now im not sure of the tyre size compared to yours, but it shows, 3.55 diff, and all three have the same tyre size, then there celica 5 speed one, trimatic (which will be the same as the 4 speed top gear) and a T700.
I've personally had a T700 in my Torana behind a 202 and it does loose some power from the larger box, so I would recommend the 5 speed for that reason...
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thanks so much!!! get too lost when trying to work it out myself, so this is a massive help.
does anyone have any ideas or advice with my diff problem???? i have a dual wheel, 10 inch drum, 3.55 diff with chev 12 bolt center, and bedford 21 spline axles which i am trying to find a good LSD for. so far the only options if have been recommended is key cutting the gears to fit the splines?? apparently this is expensive (anyone know how much??) and not sure if this is the best way to go?? maybe there is LSD parts that fit bedford???
i do have a second single wheel open diff here with the same center which i am taking apart this weekend but probably not have the parts i need. also have a swb parts beddy which i think has a holden diff or something which might be worth checking?
have tried find info on here but i just go square eyes, sorry for starting yet another post on diffs.
also will update when my gearbox is up and running. on the box i just got is 1st 3.285:1 and 5th 0.78:1 which would be awesome on the high way but have an opportunity to swap it for 1st 3.954:1 and 5th 0.85:1 which will give some extra power for take offs.
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ford and holden centers fit the bedford axles, holden would probably suit your ratios needs. would mean changing your diff center though.
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is that cutting the casing or just the internals???
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new center, housing and all
machine the bedford axle housings to slide into the housing for a tight better than factory join, axles splines are the same but holden/ford is about a 1mm fatter so a quick wipe with die grinder fixes it without any damage. This way it runs bedford axles/brakes, holden/ford diff gears, or axles can be redrilled to holden pattern very easily
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not to sure if i am up to or have the tools to put a whole new center in, reckon broaching the LSD to fit might be easier and cheaper??? but finding a holden/ford LSD that can easily be made to fit sounds like a good option, but having trouble finding a holden or ford LSD with 21 splines.
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early commodores and falcons
ford usually 2:... and 4:... while holden around the 3:...
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2:... 4:... 3:... ? is this got to do with ratios?
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2= ratio 2.7 etc 4= 4.1 etc 3=3.5 etc... these will only fit the 9" diff...
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oh ok,cheers. would the 9" be what i have?
i dont really know what i am looking for so will talk with my drive line guy on monday and give him this info.
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Dual wheel, no you have a 10", 9" were on the SWB Mk 1 models, square shape backing plate, 10" round on Jumbo's single and Dual and Mk2 Bedford Vans (well standard, anyway)
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oh well looks like broaching or key cutting (whatever its called) the gears for lsd is my best option? anyone know much that costs?
looks like this diffs going to make me bankrupt (still paying my debts off from the van rebuild) as also need bearings and seals and possibly a pinon and crown :(
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If you want to keep the drual wheels, you have one other option to fit a 9" form the Ford Galaxie family, but post 1970 models as they had the bigger spline axles in them as per your 10" shaft on the Bedford, per 1970 they had the step down spline as per the 9" Bedford. I have seen this down in NZ and was told by the guy who did it it is a straight swap with the Dual axles only, but please check this out as it was a long time ago and can't remember all the details...
Does anyone know the spline count on the 9" and 10" axles, have both here but hard to get to at the moment...
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will check it out
this may help with axle spline count
http://www.buga.com.au/index.php?option=com_smf&Itemid=2&topic=1966.msg19587#msg19587 (http://www.buga.com.au/index.php?option=com_smf&Itemid=2&topic=1966.msg19587#msg19587)
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can only find ford galaxy 28 or 31 spline :(
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Yes this is correct, but know it was done, with out any machine work, may be the center was bolted into the dual wheel diff then bedford dual axles used, the diff width was the same. But all in all something is not right, because on the link they say that no axles fit the Holden centre but they use the Holden centre here with the Bedford axles, so what ever is changed to accommodate this may be what is used on the Galaxy swap... but stand by the fact is is inter-changeable..
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hang on a minute, but didn't you say you have a 3.5 :1 diff in there already? and chev 12 bolt..... that will mean it has been changed already to something different. if you could load a photo or two, someone here (baz, hint hint) may be able to tell you more.
I would hate you to cut a converted diff that someone would happily buy/swap and you cut up a standard diff.
Or am I being delusional again........
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yep some photos would probably help, will get some on monday.
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ok i have a plan!
sent the axle off to get a truetrac wire cut to fit, and getting the rest of the diff rebuild. should be a awesome when finished, but going to be very poor after this!
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here some photo