Rear Diff options . . . OS Giken or Grannas racing’s Ford 8.8 kit

[Scotty88]

So basically, am undecided about rear diff options as am looking to change from factory auto to the grannas racing T56 kit. 
 

The current rear diff is the factory auto 200mm but for the bhp am aiming for is 1000+ so no way will it live! 
 

I’ve looked at both OS Giken and the Ford 8.8 kit but has anyone upgrade the diff to handle large power? 
 

Also the import tax is crazy expensive!

[tayr]

@Noz

[Frank Bullitt]

If you are going T56 you might as well change the rear end too as the ratios will be out. You know this set up is noisy don’t you? They don’t call it the box of rocks for nothing!

[Scotty88]

29 minutes ago, Frank Bullitt said:

If you are going T56 you might as well change the rear end too as the ratios will be out. You know this set up is noisy don’t you? They don’t call it the box of rocks for nothing!

Ehh no?! I was watching his videos on this website and couldn’t say I heard the noises . . . 
 

He did explain that the 8.8 kit ratio was a good option for the T56 hence why I was asking for everyone’s views the T56 kit seems a good kit for going manual than sourcing a V160/1 even in a good state.

 

 

[Noz]

58 minutes ago, Frank Bullitt said:

If you are going T56 you might as well change the rear end too as the ratios will be out. You know this set up is noisy don’t you? They don’t call it the box of rocks for nothing!

What setup

[Frank Bullitt]

1 minute ago, Noz said:

What setup

What do you mean?

[Noz]

Just now, Frank Bullitt said:

What do you mean?

sounds like rocks

[Swampy442]

The T56

[Frank Bullitt]

Just now, Noz said:

sounds like rocks

The T56 mate, it rattles like fudge.

[Noz]

1 hour ago, Scotty88 said:

So basically, am undecided about rear diff options as am looking to change from factory auto to the grannas racing T56 kit. 
 

The current rear diff is the factory auto 200mm but for the bhp am aiming for is 1000+ so no way will it live! 
 

I’ve looked at both OS Giken and the Ford 8.8 kit but has anyone upgrade the diff to handle large power? 
 

Also the import tax is crazy expensive!

I spoke to Grannas and he said the 8.8 would be hard pushed for 1200hp. Maybe would be okay for 1000hp, but you really will struggle to find the diff itself, if it blows, you'll have down time. Unless you import that. I've been trying for ages just to find a diff. 

I feel like a future proof idea would be the Giken. 

It'l be what I go for. Even if you get drive shafts with the T56 swap.

[Noz]

1 minute ago, Frank Bullitt said:

The T56 mate, it rattles like fudge.

 

1 minute ago, Swampy442 said:

The T56

 

Wouldn't bother me. I plan to soundproof the tunnel, to the point of obsessiveness lol.. aim to even do the dash panels. Not due to the T56, just because.

I'd still advise a T56 for anyone. If it's too noisy, try sound proofing.

[Frank Bullitt]

13 minutes ago, Noz said:

Wouldn't bother me. I plan to soundproof the tunnel, to the point of obsessiveness lol.. aim to even do the dash panels. Not due to the T56, just because.

I'd still advise a T56 for anyone. If it's too noisy, try sound proofing.

You can’t sound proof against harmonic distortion through the drivetrain, all you can hope to do is cut down the noise in the cabin. There is too much tolerance built into the gears on a T56 and that input shaft rattle would drive me insane.

If you haven’t already, I’d highly recommend trying to get a ride in one in the U.K. before committing to a kit. Have you seen any videos of the noise?

You have spent a lot of time on your car, I’d hate to see this ruin the love for you.

Drained that diff and had the cover off yet?

[Scotty88]

21 minutes ago, Noz said:

I spoke to Grannas and he said the 8.8 would be hard pushed for 1200hp. Maybe would be okay for 1000hp, but you really will struggle to find the diff itself, if it blows, you'll have down time. Unless you import that. I've been trying for ages just to find a diff. 

I feel like a future proof idea would be the Giken. 

It'l be what I go for. Even if you get drive shafts with the T56 swap.

It came to me if I wanted to push higher than 1000 like you said 1200 . . . Would it handle it?! And no way would I want to change the diff if it blows cause it’ll cost a pretty penny to replace and money lost. 
 

Am gonna go for the aluminium shaft just now but if there’s a chance to get the carbon fibre then I’ll go with that 
 

 

[Noz]

1 hour ago, Frank Bullitt said:

You can’t sound proof against harmonic distortion through the drivetrain, all you can hope to do is cut down the noise in the cabin. There is too much tolerance built into the gears on a T56 and that input shaft rattle would drive me insane.

If you haven’t already, I’d highly recommend trying to get a ride in one in the U.K. before committing to a kit. Have you seen any videos of the noise?

You have spent a lot of time on your car, I’d hate to see this ruin the love for you.

Drained that diff and had the cover off yet?

I've seen quite a few videos, haven't heard the rattling. Did these videos include the racing bell housing by any chance? As he does a cast one now, which he says makes it sound a lot nicer. It's likely the bellhousing causing that. Expect a steel bellhousing for most gearboxs would allow the harmonic gremlins to come out.

My R154 clutch is terrible, twin plate AP jobbie. Trust me won't be worst than that. Sounds like gearbox mounts are loose.

Nope. Going to change the wheel bearings and see if it sorts the noise, I can't fix the play in the diff currently, I just want a photo of the Supra by the University sign when I've got my graduation gear on  Then it's Winter. 

Edited August 18, 2021 by Noz (see edit history)

[Frank Bullitt]

34 minutes ago, Noz said:

I've seen quite a few videos, haven't heard the rattling. Did these videos include the racing bell housing by any chance? As he does a cast one now, which he says makes it sound a lot nicer. It's likely the bellhousing causing that. Expect a steel bellhousing for most gearboxs would allow the harmonic gremlins to come out.

My R154 clutch is terrible, twin plate AP jobbie. Trust me won't be worst than that. Sounds like gearbox mounts are loose.

Nope. Going to change the wheel bearings and see if it sorts the noise, I can't fix the play in the diff currently, I just want a photo of the Supra by the University sign when I've got my graduation gear on  Then it's Winter. 

Straight out of the box, quick Google search and I have found a video from the man himself talking about it.

Enjoy!

 

[Frank Bullitt]

Can you upgrade/strengthen the R154?

For the cost of a T56 kit (off to look at prices now) would you not be better off trying to source and fit V160/1?

Edit

The cost is $8695 for the GR1000 plus shipping and VAT?

Edited August 18, 2021 by Frank Bullitt
Added price info. (see edit history)

[Noz]

42 minutes ago, Frank Bullitt said:

Can you upgrade/strengthen the R154?

For the cost of a T56 kit (off to look at prices now) would you not be better off trying to source and fit V160/1?

Edit

The cost is $8695 for the GR1000 plus shipping and VAT?

Do you have a lightweight flywheel?

I'm not sure if all LW flywheels rattle. But mines pretty bad. That video isn't really against owning one, you need to be in one I think.

Have you been in a T56 supra at all? Be good to try. I can't hear that noise on videos, I can hear mine on video's, so it's really not something that bothers me.

My old stage 3 single plate clutch for lower power didn't sound rough, as soon as I've got a heavy duty clutch it sounds rough.

Yeah you can upgrade it, but you can't launch it without risk. You can hammer and drag race a T56 all day long. 600hp granny shifting gets boring. What happens when my built R154 blows up? Buy another? Money's down the drain then. I drive my current one fairly sensible, because I can't risk throwing cash away. Those grannas boxes come with a friggin warranty!

T56 kits come with clutches, everything you need. I'm best selling the R154, covering some of the T56 cost as well as op. GR700 was around £7500 18 months ago when I had a quote, shipped. Just import tax on that.

Or £6500+ for a v160, with no clutch, one careful owner (lolz). Or my 35 year old R154 lol.. that I can't launch or shift hard because I don't want to pop it. Options ant great!

Joel previously said to me, the GR700 will be fine for 1000hp and a bit of hobby drag racing on the odd occasion. I have to ask myself, can I afford for it to go wrong, not can I afford to upgrade.

[Frank Bullitt]

I have no clutch pedal, I’m a tiptronic auto I’ll have the box built by ATF and call it a day. Besides autos are quicker than manuals 

100% get a ride in one. I have one other Supra close to me and that’s it. Do you know if anyone in the U.K. has gone with the T56 or are you hoping to be the first?

I don’t envy you manual guys at all, expensive clutch to replace on regular basis, slower and should the box go pop, as you say, mucho ££££’s.

I’d just be careful with what Joel says, at the end of the day he is there to sell his product and we have spoken about traders and honesty at length. Try getting honest feedback from the guys on Supraforums in the US but also remember they have straight long roads which is also why lag isn’t too much of a problem for those guys.

[Noz]

Jamie fosta had one fitted. Few people have gone that route. Surprisingly fair few owners not on the forum.

Auto boxes can also go wrong. And for big power you still need to spend tokens. If it was all about speed I'd indeed get an auto. But its about pushing the lump of steel I'm attached too. Rather than ET times. And doing it without breaking

I've even thought about r154 gearsets. Even they can wine.

Its really not an issue, with his new bellhousing. I'd have noise over reliability anyway. T56 is the only option.

Next year. I hope to do this.

[Style]

13 hours ago, Frank Bullitt said:

Straight out of the box, quick Google search and I have found a video from the man himself talking about it.

Enjoy!

 

11 hours ago, Noz said:

Jamie fosta had one fitted. Few people have gone that route. Surprisingly fair few owners not on the forum.

Auto boxes can also go wrong. And for big power you still need to spend tokens. If it was all about speed I'd indeed get an auto. But its about pushing the lump of steel I'm attached too. Rather than ET times. And doing it without breaking

I've even thought about r154 gearsets. Even they can wine.

Its really not an issue, with his new bellhousing. I'd have noise over reliability anyway. T56 is the only option.

Next year. I hope to do this.

 

That's the T56 'Magnum' which is also what Fosta had in his. It's an uprated version of the T56 which has been pulled apart and put back together again so it's naturally going to make a few additional noises. I've heard that the Magnums are good for serious racing and not advised for the streets really as they feel terrible unless your rowing gears like a mu'fucker.

The T56 is a generic GM manual box that's factory fitted to all sorts of cars. Aston Martin Vantage & Vanquish, Vipers, Corvettes and Mustangs to name a few. So they can't be thaaaaat bad surely (I've no experience with them myself ).

I've got an OS Giken 1.5 way in a small case housing and honestly got no idea what the whole thing is rate to. I reckon prop shaft, flanges and crown/pinion will still start shredding in the 700's 

[Noz]

https://www.instagram.com/tv/CSvP-1EDy58/?utm_medium=copy_link

 

Here's a guy doing a demo check. TR700. Running noise. Idle noise. Undercar noise.

Granted its using a phone. But seems pretty minimal

[Noz]

3 hours ago, Style said:

 

That's the T56 'Magnum' which is also what Fosta had in his. It's an uprated version of the T56 which has been pulled apart and put back together again so it's naturally going to make a few additional noises. I've heard that the Magnums are good for serious racing and not advised for the streets really as they feel terrible unless your rowing gears like a mu'fucker.

The T56 is a generic GM manual box that's factory fitted to all sorts of cars. Aston Martin Vantage & Vanquish, Vipers, Corvettes and Mustangs to name a few. So they can't be thaaaaat bad surely (I've no experience with them myself ).

I've got an OS Giken 1.5 way in a small case housing and honestly got no idea what the whole thing is rate to. I reckon prop shaft, flanges and crown/pinion will still start shredding in the 700's 

Even with the upgrades. Gr1000 is obviously the dream really.

I guess the 1.5way uses the same crown pinion.

Edited August 19, 2021 by Noz (see edit history)

[Frank Bullitt]

1 hour ago, Noz said:

https://www.instagram.com/tv/CSvP-1EDy58/?utm_medium=copy_link

 

Here's a guy doing a demo check. TR700. Running noise. Idle noise. Undercar noise.

Granted its using a phone. But seems pretty minimal

It not me you need to convince

[Frank Bullitt]

1 hour ago, Noz said:

Even with the upgrades. Gr1000 is obviously the dream really.

I guess the 1.5way uses the same crown pinion.

You either use a 200mm version (small diff) or 220mm version (large diff). You know how a 1.5 way works?

Edit

1 way the LSD works under acceleration and is not effective on deceleration.

1.5 way the LSD works under acceleration and is half effective on deceleration.

2 way the LSD is effective under acceleration and on deceleration.

Edited August 19, 2021 by Frank Bullitt (see edit history)

[Frank Bullitt]

19 hours ago, Scotty88 said:

Am gonna go for the aluminium shaft just now but if there’s a chance to get the carbon fibre then I’ll go with that 

If going with a solid drive shaft you are going to need solid bushes on the diff too otherwise you are going to create problems. You can’t mix and match solid components with flexible, well you can but it’s not advised.

Edited August 19, 2021 by Frank Bullitt (see edit history)