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What gearbox is this?

Started by ven33m · 25 July 2006 · 27 replies

Preserved from CalaisTurbo. Original authors and dates are shown; archived members are not current Holdcom accounts.

ven33mArchived member
This gearbox is meant to be a RB20det. I bought and rb20det box the other day and it's very simalar to the mf5. This one looks nothing like an mf5. Did rb20s come out with 2 different boxes? It looks to me like it could be a R33 bellhousing with a VL turbo extension housing, anyone got an idea? here's another pic Some original photos have not been recovered yet.
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StockyMcStockArchived member
looks too big to be an MF5 or RB20 box. could have got lucky and scored an R33 box man! anyway if you can pick it up easily, it's not an R33 box. the body size and webbing make it look like an R33 box to me.
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ven33mArchived member
yeah i kno its not a mf5. did the silver tops hav these gearbox's i wonder and the red tops had mf5s
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VLHEROArchived member
Quote: Originally Posted by ven33m yeah i kno its not a mf5. did the silver tops hav these gearbox's i wonder and the red tops had mf5s Nah mate the Silvertop box was pretty much identical to the MF5.
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ven33mArchived member
wtf is is then
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BTArchived member
take it to a trans place and ask them or go to your nearest import wreckers and ask problem fixed Some original photos have not been recovered yet.
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ven33mArchived member
been there done that. theres no importers where i live
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ICUL8RArchived member
looks a bit like an mx7
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RB30-POWERArchived member
Its an R32 RB20DET box, similar is size to MF5, but identifiable from the extra ribbing. The R33 RB25DET box has alot of ribbing like that as well excepts its like alot bigger, comparable in size to MX7. If you have a claimed RB20DET box that looks like MF5, its probably from a Red Top RB20DET R31 Import model. Almost identicle to MF5.
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ven33mArchived member
thanks heaps mate thats wot i needed to kno buying this tomorrow n needed to kno wot it was for sure
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StockyMcStockArchived member
the extra ribbing means it's a jap box (ie NOT an MX7 or MF5) but the sheer size of it makes me think it's an R33 box? does it not look larger than an RB20 box to you guys?
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RB30-POWERArchived member
nah, nah, ill put a pic up now of R33 box. see the slope down in the bellhousing how steep it is, droping down to a narrow box centre. the r33 box doesn't drop to much its almost flat the guts is that big! pic will be up in a couple of minutes of the r33 box, just to make life a little easier in deciding.
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ven33mArchived member
Quote: Originally Posted by StockyMcStock the extra ribbing means it's a jap box (ie NOT an MX7 or MF5) but the sheer size of it makes me think it's an R33 box? does it not look larger than an RB20 box to you guys? thats why i initially thought it was a r33 bellhousing with a mx7 extension housing
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RB30-POWERArchived member
here is a pic of r33 (in front) vx vl turbo MX7 (behind) ill see if ive got a better r33 box pic as well. Some original photos have not been recovered yet.
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ven33mArchived member
so do u kno if the internals are much different on the RB20det silver top box to the mf5 box
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RB30-POWERArchived member
Hey StockyMcStock, if you want to know something you didn't know earlier today, the R34 RB25DET GTT gearbox has shotpeened gears on first, second, third and fifth from factory plus an extra, so now twin syncros on first instead of just 2nd and third in the R33 GTST gearbox.
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ven33mArchived member
any more info on the internals will be most helpful aswell
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RB30-POWERArchived member
I believe that the RB20DET box has double syncros on the first couple of gears, should be a much nicer box then the older MF5 style boxes.
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ven33mArchived member
would the cogs be any stronger/bigger?
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RB30-POWERArchived member
i would say not really. only advantage may be that the box could be newer, maybe done less km's and less fatigue from that point of view, compared to a older VL box. there isn't the space to make the gearset any bigger. if you actually compare the guts of a RB20/MF5 to a VL Turbo or R33 box, the physical size difference is massive. RB20/MF5 typically last well up to 200rwkw, or until you put a beefy clutch and LSD into the car and give it a hard time. If you have clutch slip or wheel sping it real helps take the shock loading of the smaller gearbox.
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