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Stupid Question: Can i put an MF5 gearbox into a turbo a8 motor (mx7)

Started by Petrievl · 22 Oct 2012 · 21 replies

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

PetrievlArchived member
if its possible do i change the tailshaft and box or? i have no idea what the differences are, i just cant afford to put another mx7 cause there $$$$$ farken expensive, so is it possible that i can bolt a mf5 into a turbo block instead of the mx7, cheers guys.
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HTURBOArchived member
Yes you can but you'll be crunching every gear or even blow the gearbox. Or buy a secondhand R33 or R34 gearbox & put that in. http://www.calaisturbo.com.au/showth...ht=r33+gearbox (http://www.calaisturbo.com.au/showthread.php?t=52408&highlight=r33+gearbox)
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VLT222Archived member
yeh theres no point putting an mf5 it wont take the power from the engine, thats why they are n/a boxes, r33 gts-t box will take up 250kw supposedly so maybe save up for one and put that in rather than waste more money on an mf5
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PetrievlArchived member
Oh beautiful, just what i want, err, fuck conversions im done with manual conversion stuff. i might just see if i can get lucky with an mx7, cause she isint to happy hey vlt222 just read your build thread aha, nice first car man. my first car (gold fever vl exec limited) was a piece of sheeet. again, conversions. seems easy enough but eeeehh. Some original photos have not been recovered yet.
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3lturboArchived member
As above, if you've already replace one (or more) mx7's don't bother going to an mf5. 33 boxes are cheap now, and will support alot of power (far more than 250kw), so you shouldn't have to replace it anytime soon.
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PetrievlArchived member
yeah it seems like the way to go, i heard you can also use land cruiser slave cylinders, apparently they bolt straight up, i dunno though.
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VLT222Archived member
Quote: Originally Posted by Petrievl [View Post] Oh beautiful, just what i want, err, fuck conversions im done with manual conversion stuff. i might just see if i can get lucky with an mx7, cause she isint to happy hey vlt222 just read your build thread aha, nice first car man. my first car (gold fever vl exec limited) was a piece of sheeet. again, conversions. seems easy enough but eeeehh. haha thanks man its been fun so far, still got heaps more to do with her tho.. Some original photos have not been recovered yet.
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leb vltArchived member
I've run 13.6 with a mf5, high flow t3, 3.08 LSD and and a cable tied accelerator cable as it snapped the run b4.. Copped a **** load of abuse on the street and had no issues with it wat so ever! I'm sure ppl have gone even quicker then I did with one. Obviously wouldn't recommend one if u have decent pwr but hey gota work with ur budget! At the same time just save ur money and put a 33 box in and u won't have to worry about it (within a certain degree)..
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TurismoArchived member
you finaly got a vl n solr or swapped the vs lol i had the gold vl calais in melbz. mate go r33 save up ur dosh and with vls always have a spare 2 grand lying around just in case. as things pop up. good luck mate n post a pic ---------- Post added 23-10-12 at 15:40 ---------- Guide to buying vl... step 1 sell a perfectly good car step 2 buy a vl step 3 "err, **** conversions im done with manual conversion stuff." step 4 buy a perfectly good car again and work on vl step 5 any one??? Some original photos have not been recovered yet.
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GouldyArchived member
Mx7 gearbox recoed roughly 2800$ and 2699$ for r33 gtst save ya cash and buy the recoed r33 then u have no trouble
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TheChadArchived member
the truth is nobody knows... if its a stock A8 motor and will be staying that way I wouldnt be surprised if an mf5 was ok??? Without knowing the history or condition of the box it could be fine for a while, or you could abuse it and break it in a day. mx7s are much stronger than the mf5 and have slightly different ratios. r33 gts-t boxes are again much stronger than the mx7s, and have very slightly different ratios. Reconditioning an mx7 will cost 2-3x as much as buying a ~100xxxkm r33 box, however you wont know the condition of the r33 box. the r33 box if it is in good condition will still be better than a recoed mx7 due to the synchros and ratios. another point to note: mx7 = 10" flywheel mf5 and r33 = 9.5" flywheel the r33 box will suit the mx7 tailshaft too, with just the front yoke changed IIRC. Hardly a big issue. an mf5 is shorter and needs its own shaft. (rear 1/2 of all shafts is the same length)
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tubbed1Archived member
R33 gearboxes have run consistant 9 sec passes do definetly A proven box for the $$ you pay... Stronger everything and same price if not cheaper now than the mx7 - better gear sets - better ratios and synchros - quieter - easy to source - etc - etc
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PetrievlArchived member
Quote: Originally Posted by Turismo [View Post] you finaly got a vl n solr or swapped the vs lol i had the gold vl calais in melbz. mate go r33 save up ur dosh and with vls always have a spare 2 grand lying around just in case. as things pop up. good luck mate n post a pic ---------- Post added 23-10-12 at 15:40 ---------- Guide to buying vl... step 1 sell a perfectly good car step 2 buy a vl step 3 "err, **** conversions im done with manual conversion stuff." step 4 buy a perfectly good car again and work on vl step 5 any one??? naah man still have the vs, this is for the toy, the latest edition to the family genuine lw5 mx7 berlina wagon i would of looked at yours if i wasnt already keen on the wagon haha. ---------- Post added 23-10-12 at 17:57 ---------- Quote: Originally Posted by TheChad [View Post] the truth is nobody knows... if its a stock A8 motor and will be staying that way I wouldnt be surprised if an mf5 was ok??? Without knowing the history or condition of the box it could be fine for a while, or you could abuse it and break it in a day. mx7s are much stronger than the mf5 and have slightly different ratios. r33 gts-t boxes are again much stronger than the mx7s, and have very slightly different ratios. Reconditioning an mx7 will cost 2-3x as much as buying a ~100xxxkm r33 box, however you wont know the condition of the r33 box. the r33 box if it is in good condition will still be better than a recoed mx7 due to the synchros and ratios. another point to note: mx7 = 10" flywheel mf5 and r33 = 9.5" flywheel the r33 box will suit the mx7 tailshaft too, with just the front yoke changed IIRC. Hardly a big issue. an mf5 is shorter and needs its own shaft. (rear 1/2 of all shafts is the same length) the engine is bog stock as i dont want to attract too much attention on my p's haha. not even a front mount. the r33 box is looking more and more convincing as i can just do it at work. the only thing stopping me is keeping it original. i dont have the coin or the time to rebuild the mx7, over gearbox's anyway haha. Some original photos have not been recovered yet.
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3lturboArchived member
''the engine is bog stock as i dont want to attract too much attention on my p's haha. not even a front mount'' This raises the question of how you have gone through more than one mx7 on an unmodified vlt, let alone a wagon?
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PetrievlArchived member
Quote: Originally Posted by 3lturbo [View Post] ''the engine is bog stock as i dont want to attract too much attention on my p's haha. not even a front mount'' This raises the question of how you have gone through more than one mx7 on an unmodified vlt, let alone a wagon? bought it like that man, got it cheaper cause the gearbox is on its way out. fine with me. wouldnt of bought it if it wasnt genuine.
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TurismoArchived member
good stuff just dont p platerize it as soon as you get board with it sell it please dont mod it lol Some original photos have not been recovered yet.
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PetrievlArchived member
Quote: Originally Posted by Turismo [View Post] good stuff just dont p platerize it as soon as you get board with it sell it please dont mod it lol i dont intend on it, its going to get a respray and im pulling out the engine this weekend to start building it. havent got any ideas yet so any advice on building a nice streeter turbo engine go nuts, not sure turbo was the right option i sold my fully blueprinted n/a engine for 1500 bucks out of my last calais. made 204 at the wheels haha. 25/30. Fully forged bottom end, spool rods, custom forged dome top pistons. Fully balanced 264 10.7 intake and 270 10.2 exhaust cams. Some original photos have not been recovered yet.
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bullarabArchived member
if ur not using the MX7 wanna sell MX7 sandwich plate. as 33s run smaller flywheel and starter and sandwich plate
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PetrievlArchived member
Quote: Originally Posted by bullarab [View Post] if ur not using the MX7 wanna sell MX7 sandwich plate. as 33s run smaller flywheel and starter and sandwich plate ill get back to you mate, ill get some dosh first for an r33 box i think.
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TheChadArchived member
i dont really see an r33 box as "molesting" the genuineness of the car... It's not a super limited run kind of car that requires 100% matching numbers etc. The 33 box is like a newer mx7 anyway. same manufacturer, same size, same rough shape etc. Read the thread, its basically if they made an mx7 in the 90s
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