Mazda Rotary Club

General => General Technical => Topic started by: Bucko on December 31, 2008, 10:53:23 AM

Title: gearbox rx8 into rx7
Post by: Bucko on December 31, 2008, 10:53:23 AM
hi
has anyone put a rx8 6 speed box into a rx7fd k reg is it a striaght forward swop i think the ratio are closer :burnout and not so long geared is this true i heard the gearstick moves farward a bit but do i need to use anything else ie flywheel ,driveshaft ,starter motor any info would be great , :cheers
Title: gearbox rx8 into rx7
Post by: BlitzBoy on December 31, 2008, 11:11:17 AM
Not so much of a straight swap.
You have to modify the powerplant frame and fiddle with the clutch slave cylinder and the clutch lines as well.
Chris Impey and a few guys have done this, contact Tim at RXmotors as they are the most familiar with the conversion
Title: gearbox rx8 into rx7
Post by: Bucko on December 31, 2008, 11:19:47 AM
by power plant frame is that the brace underneath
the clutch side of things am going to a pedal box set up so not sure if that makes things easier  or not
but does the box bolt striaght on
Title: gearbox rx8 into rx7
Post by: BlitzBoy on December 31, 2008, 11:24:01 AM
yes the brace that goes from the gearbox to the diff.
The box\\bellhousing has the same bolt pattern to mate it to the engine
Title: gearbox rx8 into rx7
Post by: nikp on December 31, 2008, 01:37:25 PM
But i do believe that it needs converting from a pull clutch mechanism to a push type that the 8 uses.
Title: gearbox rx8 into rx7
Post by: kbareham on December 31, 2008, 05:12:34 PM
I\'m trying to get one to fit in now - most of the problems have already been mentioned -

Power plant frame needs modifying. To get it to fit the box doesn\'t look too hard. To get it to fit at the right height so that the gearbox and engine stay at the same angle needs a bit more work. This means that all the engine pipework still fits and the prop angle is correct.

Clutch - needs a push type, but available off the shelf

Starter - the FD starter fits the bellhousing if you make up a 6mm spacer, although I haven\'t actually turned the engine over with it yet. That\'s mainly because Tim has the engine!

Gearlever - its a bit further forward. My dashboard is now in the loft!

Clutch slave nowhere near fits allthough a FC one might be modified to fit.

FD Prop looks like it might fit at a quick measure, but I have not tried it yet

The RX8 gearbox doesn\'t have as many electrical senders. It appears just to be speed and reverse lights. The FD has a neutral switch. I don\'t anticipate this being to much trouble for the PFC.


Those are the things that come to mind. There might be more as I get further into it.

Keith
Title: gearbox rx8 into rx7
Post by: Bucko on January 02, 2009, 09:01:50 PM
Hi Keith
could you let me know how your install  progresses am i right in saying the ratios are closer although more gears , are all rx8 boxes the same ?
did you use the original flywheel ,
any chance you could keep me informed on how the install goes
what do u use the car for !!
Title: gearbox rx8 into rx7
Post by: kbareham on January 03, 2009, 01:41:00 PM
I\'m not sure whether all RX8 6 speed gearboxes are the same. Mine was an ebay find from a crashed car. A bit of googling will get you the ratio\'s - they seem to be closer than the FD box because they have a direct 5th.

I have an OS Giken twin plate clutch, which comes with a new flywheel. None of this has been assembled yet so there are probably still some unknowns.

The car was my daily driver until I converted it to single turbo about 2 years ago. Its now stripped to a shell for a rebuild, where I want to lose as much weight from it as I can. I plan on it being used on the road mostly, and maybe on the strip or track days for some fun.

Keith
Title: gearbox rx8 into rx7
Post by: Bucko on January 04, 2009, 09:16:52 PM
would be interested on this as i just started a major strip down as in back to a bare shell and am thinking on this , interesting i put the same the on the usa rx7 club they say dont do it as it is a weeker box !!! but they have been a few conversions here and i have not heard a bad word from it
Title: gearbox rx8 into rx7
Post by: Papercup on January 11, 2009, 11:55:13 AM
Quote from: kbareham;570833I have an OS Giken twin plate clutch

Me too, and when it was fitted by Re:Worx they had to convert it from push to pull, or the other way around, can\'t remember.
 
Meaning that you won\'t need to change it to fit the RX-8 box; it should be the right type.
 
Andy
Title: gearbox rx8 into rx7
Post by: Bucko on January 11, 2009, 12:00:17 PM
looked at my clutch today i got the pull typr any ideas where to get the conversion
Title: gearbox rx8 into rx7
Post by: Bucko on February 28, 2009, 07:55:29 PM
hi all at last i got myself an rx8 gearbox
can anyone tell me if you finshed the insatalltion into a rx7
how did it go any problems etc have got my hands on a push type conversion
any up to date info would be great
Title: gearbox rx8 into rx7
Post by: chrisJDM on March 24, 2009, 06:32:11 PM
this is a really interesting thread would be great to see what the difference is with a rx8 box over a FD box :Thumbsup!
Title: gearbox rx8 into rx7
Post by: grinder on March 25, 2009, 09:42:29 AM
i have a FC auto - was thinking about doing a manual conversion to it - so would a RX8 box fit ??? - would seem a good idea to fit a 6 speed whilst i was doing it :D