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Riceburner

FJ20t gear ratios

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PPG/Pfitzner offer gearsets but they state on the website no warranty unless the sandwhich plate is modified to stop oil starvation on sr20 which is the same as rb20, is this a worthwhile mod (see pic)? I have it out so it's easy to do.

 

Here's the email I got back from them today.

"Reply from pfitzner PPG....

"Hello Gareth,

 

Any holes that can be blocked below the oil the level line should be; for drift application..

 

It is recommended to fill the box through the front (oil level filler plug) and the back (through the shifter), the oil will level out through the centre bearings which can take some time"

 

Sounds like a drift only requirement.

 

 

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I have a syncro question so may as well post it here too. I have new Kameari CR set and all new syncros. Do I need to lap in all syncros or only syncro on the used 4th and 5th gears?

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I can't answer your question sorry but did you get a gear set for the RB20 box or did you go a different route?

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Yeah i was just going to say the same thing, or a coating.

 

 

PMC just made me a similar setup Kameari 71C gear cluster but in 71B housings so it just bolts up.

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Here's what it looks like. I thought maybe it was to stop corrosion, but heat treatment sounds more likely.

 

Re syncros, I think I'll only have to lap the used gears as these will be the only ones that are worn/shiny.

 

EDIT. How did he fit the C gear sets into a B housing?

post-1489-144023722494_thumb.jpg

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Hi Gareth,

 

Can you explain how the bell housing is modified on r32 gtst gearbox to suit the l28?

 

 

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Hi Gareth,

 

Can you explain how the bell housing is modified on r32 gtst gearbox to suit the l28?

Unbolt r32 bellhousing,

Place in rubbish bin,

Replace with a L series bellhousing.

It needs a bit of drilling and machining to the holes in the middle.

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IIRC I plunge 1mm deep and 3.5" dia around the front lower bearing(on the inside of L series bell housing) it was also machined out to 63mm to accommodate the larger bearing. Top selector rod was machined out to 16mm.

 

Dat2kman was a wealth of knowledge on the mod and was constantly hounded with my questions. LOL. There's plenty of very knowledgeable people on this site who can help with pretty much anything.

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Hi Gareth and Dat2kman,

 

One more question, what is the advantage of the RB20 internals in the 260z box compared to the FJ20t which according to the forum bolts straight on?

 

 

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Hi Gareth and Dat2kman,

 

One more question, what is the advantage of the RB20 internals in the 260z box compared to the FJ20t which according to the forum bolts straight on?

Bigger wider better internals, more positive shifter mechanism.

Close ratio gearsets available for all types.

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Jason in Australia what are your SC rules like for gearboxes? IE are you allowed to run the 71C boxes or must the 71B cases be retained?

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Jason in Australia what are your SC rules like for gearboxes? IE are you allowed to run the 71C boxes or must the 71B cases be retained?

Rule says gearbox  internals are free.

Also, with engine, metal may be removed, stroke remains same, bore incresed by 60 thou.

Cars running injection must retain the original intake manifold and throttle body, metal may be removed from inside manifold and throttle body.

Cars running carburettor(s), the intake manifold is free

 

Yes, somewhat restricting, but, it is supposed to make it a "level" playing field. Do not start me, and the other Z guys on the disparity re Porsche & DeTomaso brakes!

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So basically the same as ours rules, but we can use fia brakes or other brakes sold ad used on the cars in period + we can use triples.

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Just opening this up again.

 

So I purchased 2 x FJ20T boxes and both had only 18mm gears not the 20mm other have stated. I have another FJ20 box here that I will pull soon to see if the last one of the 3 I have purchased as fj20t boxes actually are turbo boxes.

 

So questions for you ozzies. What cars do these 20mm fj20t gearboxes come from? The boxes I have sourced are from JDM R30 skylines. So maybe I need to find later fj20t powered cars to find one of these 20mm gearset boxes.

 

For now I have a few 71b boxes to break :)

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Mike, i've had Fj boxes from a S12 Gazelle, a dr30 skyline, and a third, nfi what, all were 3,32 first gear, ( normal comon ratios) the S12 Gazelle had 20 mm wide gears, but a mate who has three of the S12's only one has 20 mm, the other two are normal, except for the bellhousings.

Go figure!

I was peeved when two of the three were just plain old regular boxes, that i paid a bit more than normal for.

All had the 16 mm diameter 1st/2nd selector rod, regular 71B's have a 14mm diam selector top rod.

 

The 71 C gearsets are 20mm the 71B's are 18mm

There was mention on this site about wider fifth gear sprockets in a FJ-T box, 18 mm vs 16mm if i recall?

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