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St170 to Mazda rx8 gearbox.
Pigsy - 23/5/19 at 11:52 PM

Hello everyone. I have mated an st170 to an rx8 6speed box. St flywheel. Ford transit heavy duty clutch complete. Rx8 slave cylinder and thrust bearing and pivot lever/arm. 10mm adapter plate.

Iím getting problems getting in to gear. I understand the problem of needing a longer slave pusher ďpinĒ. I made one 10mm longer to make up for the adapter plate thickness.

Has anyone any useful suggestions as I donít want to pull the engine and box again. Itís a lot of work in the mgb gt that Iíve put it in. Only just fits.

Thanks ĒPigsyĒ.


Nickp - 24/5/19 at 07:43 AM

Are you getting full travel of the slave cylinder?


Pigsy - 24/5/19 at 09:05 AM

Yes I believe I am. Itís a new slave cylinder and itís bled well.


big_wasa - 24/5/19 at 09:52 AM

Nobody uses the St dual mass flywheel, it's a very heavy piece of scrap.
They are a lot thicker than a solid flywheel. You may be over compensating if your bassing it on what others have done with a solid flywheel.
Have you used the transit cover plate or the st ? The st won't take the cush drive off a conventional clutch.


Pigsy - 24/5/19 at 04:14 PM

Hi. I did use the dual mass. It was recommended by quite a few people who had problems with the single mass flywheel. Ho hum. The clutch was complete and had the cover. Iím using the Rx8 thrust bearing. The clutch was very much like the st170 set but had the different spline count. I donít know the Rx8 cover depth.


CosKev3 - 24/5/19 at 04:16 PM

Does the input shaft reach to the spigot bearing?

Presuming you've fitted a spigot bearing for RWD set up?


Pigsy - 24/5/19 at 04:33 PM

Prompt reply thanks. I believe it does. There are no unusual sounds or vibrations coming from that area. I had the car on stands until yesterday evening and could run it and once in gear to start it. Interestingly, I could with difficulty change gear to second using the clutch pedal. It wonít go into gear with the clutch depressed and just crunches cogs. It just did not push the pivot arm enough to get it in gear or for a good change. I have lengthened the slave cylinder arm this afternoon, but just too much and itís not in the car yet.

Iím chasing the receipt from the clutch and cover plate. I want to be sure of what Iím saying regarding what it goes into.


Pigsy - 24/5/19 at 04:38 PM

Sorry but what did you mean by: The st won't take the cush drive off a conventional clutch.


big_wasa - 24/5/19 at 04:59 PM

The st uses a dual mass flywheel and a solid clutch plate. Conventional clutches would have springs to cushion the drive line and a solid flywheel. This hub of springs and rubber has to fit in the cover plate or sometimes the flywheel. If this is the wrong way around or in a cover plate that doesnít clear, you wonít be able to depress the clutch properly. But I donít know the clutch you have used.

I still havenít heard of anyone picking an St fly over a solid one. Any ideas why ?


Pigsy - 24/5/19 at 05:22 PM

A local mechanic with and st converted had this problem: The new flywheel had a very slight vibration. He took it for a ride and while revving the engine it smashed throught the side of the block, smashed the bellhousing to pieces, smashed the rad and dented the bonnet. It shattered in 2 sections. Could have been faulty but it was too damaged to tell. It was a lightweight but not cheap. He tunes stís. Has happened to him more than once but not this seriously.


rusty nuts - 24/5/19 at 05:46 PM

Was he using a flywheel that had been lightened or was it a lightweight steel flywheel? In suspect your lever pivot maybe too short , a longer one would bring the thrust bearing closer to the cover ? Think you would have to measure the clearance you have at the moment?


CosKev3 - 24/5/19 at 07:08 PM

quote:
Originally posted by Pigsy
Prompt reply thanks. I believe it does. There are no unusual sounds or vibrations coming from that area. I had the car on stands until yesterday evening and could run it and once in gear to start it. Interestingly, I could with difficulty change gear to second using the clutch pedal. It wonít go into gear with the clutch depressed and just crunches cogs. It just did not push the pivot arm enough to get it in gear or for a good change. I have lengthened the slave cylinder arm this afternoon, but just too much and itís not in the car yet.

Iím chasing the receipt from the clutch and cover plate. I want to be sure of what Iím saying regarding what it goes into.


You believe it does have a spigot bearing?

Pretty sure you would have had to add one when you converted it?

Good point about the clutch plates above,dual mass flywheel use a unsprung clutch plate,solid flywheels use a spring plate,they ate not interchangeable


big_wasa - 24/5/19 at 07:50 PM

St comes from the factory with a spigot bearing.


Pigsy - 24/5/19 at 10:14 PM

I believe that the splined lay shaft that the clutch slides on goes into the spigot bearing. It has a spigot bearing. I would not have left it out.


Pigsy - 24/5/19 at 10:26 PM

The flywheel came from a company selling lightened steel flywheels. Don't ask me who.

The clutch cover was a Ford Focus Transit 1.8 Borg & Beck. The plate was an MGB 1800 BORG AND BECK HEAVY DUTY CLUTCH.
The cover fitted the flywheel as it should. The plate was the right size and thickness.

I have lengthened the slave push rod by 13mm. 5mm to make up for the adapter plate and 8mm to take the slack with the push rod seated deep in the slave cylinder. I will try it tomorrow and let you all know.


Pigsy - 24/5/19 at 10:31 PM

The lever pivot is the standard rx8 item as used with this gearbox. It fits well.


CosKev3 - 25/5/19 at 08:31 AM

quote:
Originally posted by Pigsy
I believe that the splined lay shaft that the clutch slides on goes into the spigot bearing. It has a spigot bearing. I would not have left it out.


Does the shaft reach the spigot ok though once the 10mm adapter plate is added?


big_wasa - 25/5/19 at 09:00 AM

Iíve never heard of one of the reputable steel flywheels exploding ie Ttv, Turbosport, Raceline.

I have seen some pretty scary looking lightened cast flywheels.

But if you where worried an Oem Zetec flywheel would be a better start than an St170 flywheel. They where so crap that you where lucky if one lasted three years and the clutch couldnít cope with a standard St so was changed half way through itís life and upped from 230mm to 240mm. In cars with more torque like a diesel Mondeo they chewed through the flywheels even quicker with the debris taking out the csc and the starter at the same time.


Pigsy - 25/5/19 at 11:08 AM

Thanks for that, but, as it's all fitted and in the car I will leave it there. Hindsight is the only exact science and at the moment if it comes to it, then i will do it. You no doubt have a wealth of knowledge that is far greater than mine.

By the way, its not my first engine swap, Ive done many on Morris minors, cortina's, escorts and the like. Its the first new school with a modern ecu, electronic ignition, itb's etc

Im in my 60's and not well at all. i"m struggling but wont give in. its taken 2 years so far. A couple of decades ago it was a months work. Ho hum.


Pigsy - 25/5/19 at 11:14 AM

Does the shaft reach the spigot ok though once the 10mm adapter plate is added?

Adapter plate is actually 6mm.

As I said, I believe it does. I measured before hand and I have no vibrations or wobbling when the gear is engaged and everything is turning over at high rpm with the wheels of the ground. I have no problems with the spigot shaft. Take it as engaged. The problem is i'm sure the slave cylinder and pivot arm length. Im hoping to know this afternoon.


Pigsy - 25/5/19 at 11:16 AM

I have lengthened the slave push rod by 13mm. 5mm to make up for the adapter plate and 8mm to take the slack with the push rod seated deep in the slave cylinder. I will try it and let you all know.

Please read the threads. I appreciate the help but please see what is written first.


CosKev3 - 25/5/19 at 11:24 AM

I'm out,help yourself!


Pigsy - 25/5/19 at 02:40 PM

Thanks. If anyone else is listening, the slave cylinder is not getting full travel from completely compressed. Itís the clutch master not pushing enough.


big_wasa - 25/5/19 at 04:46 PM

If your not getting enough travel at full stroke the option is to change master to slave ratio. Ie one or both with a bigger or smaller bore.


I am not telling you I know better or I know everything. I am just sharing my opinion and research and experience on the St flywheel and clutch combo.

The combination you have put together is pretty unique.

[Edited on 25/5/19 by big_wasa]


Pigsy - 25/5/19 at 05:23 PM

Thanks so much for the reply. I appreciate it very much. The mgb clutch master is an 18mm bore with a 25mm throw. I noticed this on eBay: Tilton 74 Series Universal Brake / Clutch Master Cylinder 1 1/8" Bore Size. The bigger bore will make for a very stiff pedal I expect but I can live with that. The extra throw will be good. I think that there is another 6mm travel in the slave cylinder. I hope Iím right.

I have no problem with any suggestions. I was just being asked the same questions repeatedly and being told of for using a dual mass flywheel.

I appreciate your genuine help. I will just be happy if it works reasonably well


Pigsy - 3/6/19 at 06:21 PM

If you were going for a clutch setup on the st170 engine with rx8 box, what setup would you choose?


big_wasa - 3/6/19 at 07:48 PM

The Rx8 box shouldnít make much odds. I was not ďtelling you of forĒ using the St170 flywheel. Just giving reasons why nobody else uses it.

If your sticking with the dual mass fly as Iíve said itís a unique combo and your going have to keep playing until you have worked something out.

If your thinking of changing the flywheel to a solid unit.
Standard 1.8 220mm flywheel and good quality clutch should be ok for a standard carb / injection st.

Standard 2.0 240mm is heavier but will hold more torque.

Turbo, standard 2.0 with Focus Rs clutch.

All of these are tried and tested and Iíve never heard of a standard manufactures flywheel grenadine.
I wonít bother suggesting light weight flywheels as you have already made your feelings clear.

[Edited on 3/6/19 by big_wasa]


Pigsy - 3/6/19 at 07:51 PM

I am getting a full 10mm travel with the thrust bearing going against the pressure plate/clutch cover and yet the clutch plate is not releasing. Any ideas why?


Pigsy - 3/6/19 at 07:52 PM

I am getting a full 10mm travel with the thrust bearing going against the pressure plate/clutch cover and yet the clutch plate is not releasing. Any ideas why?


Pigsy - 3/6/19 at 08:00 PM

Thanks Wasa. I was thinking of the Standard 2.0 240mm with Focus Rs clutch. Is the RS clutch 23 spline? Thats why i used the MGB clutch plate.

What is the depth of the 2.0 240mm flywheel please? With the dual mass fitted and all the "freeplay" removed so the the thrust bearing actually is about 1mm off the cover plate fingers it is pushing in 10mm and its not enough. I fitted the larger master cylinder with an extra 25% push than the MG unit and it will not go to the floor with the RX8 slave cylinder. If the 2.0 240mm is thinner then it has no chance of clearing............ or am i wrong.


Pigsy - 3/6/19 at 08:04 PM

Like this?

https://www.ebay.co.uk/itm/Ford-Pinto-Clutch-Kit-Lightened-Flywheel-240mm-23mm-Spline-2-0-Hotrod-Kit-Car/254093726479?hash=item3b292a930f:g:vT8AAOSwNT NcGzlz&frcectupt=true


Pigsy - 3/6/19 at 08:18 PM

I noticed this:
https://www.ebay.co.uk/itm/Genuine-Ford-Focus-RS-MK1-Flywheel-2-0-Zetec/123772552969?hash=item1cd16b4709:g:xwkAAOSwN0tc4H0u&frcectupt=true

And this:
https://www.ebay.co.uk/itm/Ford-Escort-Ii-2-0-Rs-3-Piece-Complete-Clutch-Kit-100-Saloon-03-73-02-77/133032868688?hash=item1ef9607b50:g:O0sAAOSwFEpahfM 6

It seems to fit everything going ford wise.


big_wasa - 3/6/19 at 08:26 PM

Rs clutch is made by Ap and is the same size as the standard 2.0 it uses the same flywheel and runs in a version of the mtx75 although not identical to the focus / Mondeo casting..

Flywheels drilled for a pinto clutch, the clutch is deeper so no need for the thicker thrust bearing in a T9. Again your adding more variables into the mix.

Have you had a chat with Jonathan who makes some of the Rx8 adapters available. He nearly always recommends a standard flywheel and clutch. He runs a Zetec in his Escort with the Rx8 box and gives it death.

Just ask him what he is using..

I think it will be a standard Zetec flywheel and clutch.

You will only need the Rs Ap clutch if you have a very serious St or forced induction.

[Edited on 3/6/19 by big_wasa]


big_wasa - 3/6/19 at 08:31 PM

The Focus Rs flywheel is the same as any 2.0 Zetec by buying an Rs one you are paying the Rs tax for a flywheel that will have had a harder life and got much hotter.

The clutch you have linked to is not a Focus Rs clutch. If you find a genuine Ap Rs clutch your eyes will water lol


big_wasa - 3/6/19 at 08:33 PM

I may be able to have a measure at the week end if I get a chance to fit my new flywheel.


Pigsy - 3/6/19 at 09:31 PM

Thanks for that Wasa. Re: a chat with Jonathan, is he just on as Jonathan?
A chat would be good. I bought my adapter from a John, I think from Wales.

I noticed the pinto clutch with flywheel and thought a good price. Are they reasonably strong? Im not racing it though the odd burnout would not go amiss.


big_wasa - 4/6/19 at 05:06 AM

The pinto fly wheel doesn't fit a zetec / st.

You can have a zetec fly wheel re drilled to take a pinto clutch but your then mixing things up again. The advantage of this in a zetec / t9 is no messing around with thicker thrust bearings and you get more clutch travel more clutch travel.

John has a face book page called Rx8 adapter plates or something similar.

[Edited on 4/6/19 by big_wasa]


Pigsy - 4/6/19 at 07:03 AM

Thanks Wasa


big_wasa - 6/6/19 at 06:52 PM

https://www.ebay.co.uk/itm/FORD-COUGAR-2-0-MANUAL-1999-FLYWHEEL-AND-STARTER-RING-GEAR-928M6398CB/162791078023?hash=item25e71ab887:g:IPgAAOSwDkVaJ8UD


Pigsy - 6/6/19 at 08:11 PM

I removed the complete flywheel today. The Dual mass flywheel is 54mm deep. Quite a lump. Do you happen to have a zetec 2.0/1.8 that I could buy from you? Im in Southampton so postage needs to be added.


big_wasa - 7/6/19 at 05:01 AM

Sorry I don't, I flogged all my zetec spares of a few months ago.


Pigsy - 7/6/19 at 12:48 PM

I purchased the cougar flywheel thanks. Incidentally the mgb b&beck heavy duty clutch and cover is a bolt on job with the st170 flywheel. no mods needed. Its approx 57mm deep. am i right that thats the same as a pinto clutch cover? The dual mass is 54mm deep.


big_wasa - 7/6/19 at 01:06 PM

Nope,

The pinto cover plate is deeper than a Zetec hence why you would need the thicker cct133 thrust bearing in a t9 to make up the difference.

Itís not a bolt on fit to a Zetec 220mm flywheel, it needs redrilling. The clutch plate is also slightly smaller at 215mm.

The debate about a rwd clutch having more travel has gone on for years. Both ways work.

If you now have a 240mm fly I would advise making life easy for your self and use a standard Mondeo / focus 240mm clutch plate and cover. The starter motor is the same. Itís then just a case of adjusting either the slave pushrod length or the pivot point or a little of both.


Pigsy - 7/6/19 at 01:43 PM

Thanks for that. I have made a plate about 8cm long with a long slot to take the bolts for the slave and welded it to the slave cylinder where the two attachment ďtabsĒ were. It will give me about 4cm adjustment backwards and forwards. That will help with the thrust bearing to clutch cover alignment. I thought that the plate may have been in back to front, but not so.

Will I need to re-drill the cougar flywheel? Thanks for the tip on the clutch from a mondeo/focus.


Pigsy - 7/6/19 at 02:04 PM

Just reread the posts. Drilling not necessary.


big_wasa - 8/6/19 at 08:42 AM

Well itís chucking it down so no car time for me today so I wonít get anything measured.


Pigsy - 8/6/19 at 11:07 AM

Same here. I donít blame you.


Pigsy - 10/6/19 at 12:08 PM

What do you think of this?
https://www.ebay.co.uk/itm/For-Ford-Cougar-EC-Coupe-2-0-98-01-2-Piece-Sports-Performance-Clutch-Kit/392203687544?hash=item5b51295678:g:YvMAAOSws0pcKFO S&frcectupt=true
They poke 170 horse and this is a stage 1 kit.


big_wasa - 10/6/19 at 01:40 PM

My opinion, you donít need a sports clutch unless you have forced induction ie turbo or supercharger.

A good quality Oem clutch is more than adequate. Ideally I would look for an Oem motorcraft clutch of a crate engine. There was loads of them kicking about as most wanted the 1.8.

After that, any of the recognisable brands. Sach, Luk, Even the old Qh.

It needs to handle torque, the 2.0 was designed to pull a ton and a half car, five adults and a caravan up and down the hills for at least 100k miles.

Check the specs before spending your cash.

https://www.ebay.co.uk/itm/FORD-MONDEO-Mk1-2-0i-4x4-CLUTCH-KIT-QKT691/223481285583?hash=item340885cbcf:g:ua8AAOSwIM9a~pYQ


big_wasa - 10/6/19 at 01:43 PM

This one has all the specs.

Cheap because who fits a clutch to a mk1 Mondeo ?

https://www.ebay.co.uk/itm/FORD-MONDEO-2-0I-16V-4x4-2-piece-clutch-kit-1994-1996-QKT1613AF/181997397557?hash=item2a5fe3e635:g:7NwAAOSwoydWniLv


Pigsy - 10/6/19 at 06:02 PM

Sound logic and a good price to boot. The MG is a lot lighter than the Focus. About two thirds the weight. I am running ~Suzuki itb's which might give it 190bhp at a push.

Thanks again.


big_wasa - 10/6/19 at 06:36 PM

Yeh but only around 150ft/lb torque.

They slip on a turbo Zetec putting out 220~250ft/lb +


Pigsy - 10/6/19 at 07:38 PM

I think I will be ok. Not much of a tyre fryer. Iím not blowing the engine or anything like that.


Pigsy - 11/6/19 at 07:12 AM

st170: Max torque (lb ft @ rpm) 144 @ 5500.


Pigsy - 11/6/19 at 07:18 AM

The clutch will take 132 ft/lb in the mondeo 4x4


Pigsy - 11/6/19 at 05:16 PM

I missed that clutch kit. Will an RS Turbo Ford CVH 220mm fit? its a 220mm diameter. ive seen one at a reasonable price.


Pigsy - 11/6/19 at 05:27 PM

The 220mm is not the clutch diameter but the flywheel diameter. Forget I asked.


big_wasa - 11/6/19 at 05:35 PM

Your making hard work off this for your self.

The 220mm cover plate isnít going to mount to a 240mm flywheel. Have a look at some on line photos and you will see why.


Pigsy - 11/6/19 at 05:41 PM

Hi. I realised as soon as i asked, hence my last comment. Im just want to be sure that what I fit will take the torque and hp. Im just learning what is best, all be it slowly. I know 60's and 70's fords, not later. Thanks for helping.


big_wasa - 11/6/19 at 05:48 PM

I would prefer a brand name but knock of postage and it doesnít get any cheaper

https://www.ebay.co.uk/itm/NEW-CLUTCH-KIT-FOR-FORD-COUGAR-FOCUS-2-0-MK1-MONDEO-MK2-2-0-1996-to-20005/163490440769?hash=item2610ca2641:g:4H4AAOSwUP5cP0 ~D


big_wasa - 11/6/19 at 05:54 PM

Like I say there are plenty of zetecs on throttle bodies running a standard 1.8 flywheel and Oem clutch. You know have a 2.0 flywheel. Get a matching clutch and you only have to play with the slave cylinder / clutch fork pivot a little.


Pigsy - 11/6/19 at 06:08 PM

Thanks. Removing the box on the MG is a real trial and best avoided.


Pigsy - 11/6/19 at 09:46 PM

Just ordered CLUTCH KIT FOR FORD COUGAR FOCUS 2.0 MK1 MONDEO MK2 2.0 1996 to 2005. £37.95.
The previous one suddenly found they had no stock!!!! Ho hum!


Pigsy - 11/7/19 at 03:42 PM

Hi Wasa . Im so pleased to say that after a two week break, I have fitted the Cougar/Mondeo flywheel and clutch complete. It works very well. Its highlighted a leaking master cylinder but that is a quick replacement. Thanks very much for your help!!!!


big_wasa - 11/7/19 at 05:22 PM

Glad your sorted.