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T9 or MT75 Box
Padstar - 15/5/12 at 04:45 PM

What is teh general opinion on these gear boxes? The Type 9 Sierra unit seems readily available in refurbished states or 2nd hand with several of the MT75 units available on ebay 2nd hand ready to be refurbed.

I can see that the Type 9 has been used everywhere, but are people now opting for the newer MT75 unit instead?

Are there any advantages / dissadvantages of using 1 over the other?


hootsno1 - 15/5/12 at 04:59 PM

First gear in the mt75 is a bit short. But the will Handle a lot more bhp than the type 9 and it can be made to fit the duratec as this is what I'm doing.
As it will Handel 250 bhp without any internal mods where as the type 9 will not handle much more than 180 bhp


Not Anumber - 15/5/12 at 05:17 PM

The MT75 is a wider gearbox which requires more clearance. You wouldn't be able to retro fit a MT75 gearbox into a chassis that was made for a Type 9. If in doubt make the chassis wide enough for an MT 75 anyway even if you don't fit one to start with as the door is then open for any future deployment of larger gearboxes including the MT75 and others such as the Mazda MX5 box which is becoming an increasingly popular choice.


Padstar - 15/5/12 at 05:55 PM

What is the Mazda box referred to (model) so I can do a bit of research on them.

Does the MT75 fit the duratec without any mods?


metro6r4 - 15/5/12 at 07:04 PM

what engine are you using mate?


Not Anumber - 15/5/12 at 07:30 PM

The Duratec engine fits ok onto the Mazda MX5 box- experience from others on the forum suggest you have to use the Mazda flywheel, clutch, bearing and starter motor. It's less work than getting it onto a MT75 and a lot less work than mating it with a Type 9.

If I was building with a Duratec engine this is the way i'd go.

It's not an upgrade path that is open to me though as the chassis on my Indy was made for the narrower but very popular Type 9 gearbox


Padstar - 15/5/12 at 07:35 PM

Had planed to use a ford duratec engine. 1.8 or 2.0? But have not gone too deep on research


MkIndy7 - 15/5/12 at 11:40 PM

quote:
Originally posted by Not Anumber
The Duratec engine fits ok onto the Mazda MX5 box- experience from others on the forum suggest you have to use the Mazda flywheel, clutch, bearing and starter motor. It's less work than getting it onto a MT75 and a lot less work than mating it with a Type 9.

If I was building with a Duratec engine this is the way i'd go.

It's not an upgrade path that is open to me though as the chassis on my Indy was made for the narrower but very popular Type 9 gearbox


The 5 speed MX5 box fitted fine down our old Indy chassis, just needed the Mazda side mounts lopping off and the bottom ones adapting but clearance wise, width of the box etc it fitted fine. I won't say it slid straight in no messing but it was certainly no real headache.

Perfect ratio's for the Duratec seen as it was designed to work with that engine and lighter weight combo.. Remember tho it's only the 2007-Mk3 NC (N7 gearbox) that fits the Duratec.


Padstar - 16/5/12 at 07:09 AM

Mk3 mazda boxs seem very expensive compared to other models.

Was thinking have the chasis made to suit a MT75 but put a Type 9 in there to start off with as they are still readily available and relatively cheap / can be refurbished yourself. This will then leave me the option of fitting the newer Ford box at a latter date if anything goes wrong.

One question is that someone raised an issue about the Type 9 not being able to handle the power of newer engines? Would there be an issue pairing a T9 with a duratec either fitment wise or dealing with the power?


MkIndy7 - 16/5/12 at 09:11 AM

Plenty of people on here have put quite a few horses more through a type 9 than is often recomended and they've been fine or eventually bought uprated gearsets

If Definately going Duratec our view was, Why spend the best part of £300 buying a bellhousing and associated parts to mate a modern lightweight engine to an old questionable condition with pretty much useless first gear box that's 10kg heavier.

We tend to stick to the idea, whilst sill being sensible with money that if it's worth doing its worth doing right and right first time so we can enjoy the car rather than spending even more time meddling with it, so £300 for what is regarded as one of the sweetest changing boxes was a nobrainer.

We probably saved a large proportion of the gearbox cost by using the standard inlet manifold etc, while it may not be the most out and out powerful Duratec's out there it's plenty fast, unbelievably drivable and easily returns high 30's to the gallon!.


Padstar - 16/5/12 at 09:32 AM

We're the mods to mate it with the duratex simple enough?

[Edited on 16/5/12 by Padstar]


MkIndy7 - 16/5/12 at 10:11 AM

The mk3 MX5 has the Duratec engine in so it bolts straight up, and worse case senario for parts is needing the Mx5 flywheel, clutch plate, pressure plate, starter and external slave cylinder but if your buying from a breaker these are likely to be available aswell and a few of those parts would be needed for a conversion bellhousing anyway.
Depending on your donor Duratec you might be able to re-use some of the above parts off that if suitable.

Probably the only other thing to mention is the Mx5 box tilts the engine over whereas the Bellhousing conversions keep it upright, and most of the RWD sump kits are for the straight up engine. We did a trackday at Blyton last year with the FWD ST150 sump on with now sign of problems but low clearance on the road and have now had a RWD (ranger possibly) one cut n shut at a local fabrication place to give plenty of clearance but as yet is untested.


Not Anumber - 16/5/12 at 11:13 AM

What gearbox does the Ranger have with the Duratec engine ? Is this the killer combination thet many on here will be going for when the later Rangers start becoming more widely available as breakers ?


MkIndy7 - 16/5/12 at 11:25 AM

quote:
Originally posted by Not Anumber
What gearbox does the Ranger have with the Duratec engine ? Is this the killer combination thet many on here will be going for when the later Rangers start becoming more widely available as breakers ?


The rangers are pickups like the Mitsubishi L200 etc which would likely have the wrong ratios and a transfer box attached, only likely to be any use for the RWD sump of anything. What I've never seen is a Mx5 Duratec sump as to weather they would be any use for our application.

As you'll find on here therese never really a 'killer combo' for anything as people have vastly different budgets and different aims at the end of it all.
But as far as an Original as possible install using full manufacturers parts I should imagine the Duratec Mx5 combo to be pretty hard to beat.


cjwood23 - 16/5/12 at 11:39 AM

Does the zetec fit straight onto the MT75?

I had the MT75 in my old TVR, 1st was a bit short but the other ratios seemed fine.

I guess that if you want to drag or sprint your car then the short 1st might be an issue.

Another thought - isn't the MT a hyrdaulic clutch?


Padstar - 16/5/12 at 12:37 PM

So something like this coupled with a duratec engine would be good?

Mazda MX5 Mk3 NC (2006->') 1.8L Petrol 5 Speed Manual Gearbox | eBay

Are they easy to refurbish yourself?


MkIndy7 - 16/5/12 at 01:19 PM

That looks exactly that part all the right description and numbers..

I shouldn't imagine one would need refurbishing atall.. I think ours had about 30,000 miles on it, drained the oil took the rear casing off for other reasons and it was as clean as a whistle. As far as rebuilding one should it need it I think the main box of gear is very similar to the older mx5's just the cast on bellhousing and tail end of the box that are likely to be different


beaver34 - 17/5/12 at 10:15 AM

quote:
Originally posted by hootsno1
First gear in the mt75 is a bit short. But the will Handle a lot more bhp than the type 9 and it can be made to fit the duratec as this is what I'm doing.
As it will Handel 250 bhp without any internal mods where as the type 9 will not handle much more than 180 bhp


there is a guy with a zetec turbo on here run 300bhp in a stock type 9 box, there stronger than you think

i think you would be going some to break one that does not have any faults


Padstar - 18/5/12 at 01:01 PM

If going with the mazda gearbox can i still use alternative rear diff or am i then comitting to the mazda option?


MkIndy7 - 18/5/12 at 01:27 PM

quote:
Originally posted by Padstar
If going with the mazda gearbox can i still use alternative rear diff or am i then comitting to the mazda option?


You can use any diff you should wish, you just have a propshaf mtade up with a mazda yolk on the gearbox and and what're you like on the other.

I've struggled to find the original Mazda diff Ratios to match the gearbox but I think their around the 3.9-4.1 ratio going from what ive found online and their quoted revs at 70mph etc.

We ran what I though was a 3.62 Sierra diff lastyear and that would really cruise, 2750rpm at 70mph but if you wanted to overtake with the full potential from cruise you'd have to drop 2 gears to really make it scream... Turned out it was 3.38 when we too it out so were going with a 3.62 LSD this time.


Padstar - 22/5/12 at 01:11 PM

Are diffs straight forward to rebuild?

I have been offered a mark 1 MX5 diff for a drink but it has seen better days. Would it be worth me taking and working on rather than looking for a newer unit?

I have decided on the MX5 gear box so would they be a direct ratio link.


MkIndy7 - 22/5/12 at 02:25 PM

I'd say a lot depends on what car it's going in and the intended donor car the kit is based on.
If its a Sierra based kit an MX5 diff etc will just complicate things even further as you then have the driveshafts etc to consider.

The Ratlos to suit the Mx5 gearboxes are less desirable ones of the sierra range so they shouldn't be too hard to get hold of.
Rebuilding Sierra diff's looks quite complicated without the correct spacers and tools to do the job and not particularly cheep for the parts either.


Padstar - 22/5/12 at 02:46 PM

Planning to comit to an MX5 donor. Looking at an engine gearbox from a 2007 MX5 and a rear diff from a mk1. Should work ok?


MkIndy7 - 22/5/12 at 03:39 PM

If your going for a Mx5 donor then you'd be aswell buying a whole Mk1/2 Mx5 with a blown engine or crash damage than trying to source individual bits here be there.

Should be ok, You'd have to find the Gearbox and ratios of the Mk1 vs the Mk3 and compare but they should be in the right ballpark.


Padstar - 22/5/12 at 05:41 PM

Was planning on using as many "newer" parts as possible from a MK3 via eBay and the like as I wanted to steer clear of older/well used parts to make way for newer ones as I had planned on it being a regular track day car and thought that would be a more reliable option for this use. I also have limited space that will not allow an untaxed vehicle to be broken in.

Seemed to me that using the net u could get many if the required components from cars broken by others at a reasonable price.

Am I going completely wrong here?


MkIndy7 - 22/5/12 at 05:50 PM

quote:
Originally posted by Padstar
Was planning on using as many "newer" parts as possible from a MK3 via eBay and the like as I wanted to steer clear of older/well used parts to make way for newer ones as I had planned on it being a regular track day car and thought that would be a more reliable option for this use. I also have limited space that will not allow an untaxed vehicle to be broken in.

Seemed to me that using the net u could get many if the required components from cars broken by others at a reasonable price.

Am I going completely wrong here?


The chances are all the kits that use a MX5 as a donor are for the Mk 1 and 2... The Mk3 I would guess is quite different.

Probably 5 stud hubs vs 4 for the Mk 1/2, it might have a wider drivetrain so the driveshafts are longer, the steering column might be different to accomodate the duratec... this is whereyou really need to do your research and buy wisely.

A single donor if usually by far the cheepest way of doing it as there's all sorts of little things you don't realise you need that end up costing.