The gear change in my Griff is totally different.
The gear change in my Griff is totally different.
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Uncle Fester

Original Poster:

3,114 posts

238 months

Sunday 19th October 2008
quotequote all
The gear change in my Griff used to be slow and obstructive. Especially when accelerating hard it would sometimes refuse to go from second into third.

When I got the car back from V8 Developments it had a totally different shift. It was about as slick and quick as any gear change can be.

The only thing I can think of that has changed that could have affected the gear change is the engine mounts.

The previous mounts were standard and about 4 years old, but in condition. The replacement mounts V8D fitted are the new polybush mounts.

Apart from that there was nothing they did that I can think would affect the gear change.

Could the reluctant standard gear change be a result of the engine mounts flexing and this be cured by the new mounts?

Anyone else noticed an improved gear change after fitting the new type mounts?

GreenV8S

31,020 posts

314 months

Sunday 19th October 2008
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Can't think why the engine mounts would make a difference, did they do anything else at all?

Ballistic Banana

14,706 posts

297 months

Sunday 19th October 2008
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oil Change maybe?

Uncle Fester

Original Poster:

3,114 posts

238 months

Monday 20th October 2008
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The full job list was.
Engine out.
Top hat liners.
Internal dynamic balance.
All the bits for a full rebuild, bearings, rings, etc.
Clutch, one of V8D’s specification, non standard.
H404 camshaft.
Cross bolt crank.
Refit.
AFAIK V8D didn’t change the gearbox oil.
Prior to the work there was no sign of the clutch dragging or misbehaving in any way. It was fitted by TVR Power about 11K miles previously. V8D reported it in good order, but as the engine has had quite a power increase since it was fitted, I felt that something stronger was in order to prevent having to take it out again anytime soon. This is the obvious suspect, but I don't think so in this case.

The impression is that under full power the engine is more stable. I have convinced myself that the engine was twisting excessively on the original mounts under full throttle and getting the components out of line. Hence trying to go 2nd into 3rd and not being able to find a gear. I would have expected a clutch cause to do it all the time.

Now it just snicks between gears with precision as fast as you can move the hand. Never misses baulks or is in any way obstructive.

I wondered if anyone else had made the same engine mount change and experienced a big improvement. The mounts put in were the Poly mounts here.
http://www.sc-power.co.uk/SC%20Power%20Engine%20Mo...

Pupp

12,968 posts

302 months

Monday 20th October 2008
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The explanation is nothing so sophisticated I suspect... the linkage for the remote gear lever runs very close to the handbrake lever and bracketry... it is possible for the two to interfere, especially if the handbrake has been bent by being snatched. If anyone is suffering a 'notchy' change (especially first-second) than worth just pulling the brake on a click or so to see if that eases it (moves the bolt that catches out of the way). Could be the gear box has gone back in in a slightly different position where this no longer occurs.

HRG

72,863 posts

269 months

Monday 20th October 2008
quotequote all
Your old clutch was probably toast.

spend

12,581 posts

281 months

Monday 20th October 2008
quotequote all
HRG said:
Your old clutch was probably toast.
Spoilsport!

ETA: Is it possible to get the engine out without disturbing the box anyway?

Edited by spend on Monday 20th October 12:43

Uncle Fester

Original Poster:

3,114 posts

238 months

Monday 20th October 2008
quotequote all
HRG said:
Your old clutch was probably toast.
Not according to Rob at V8D.

But he is likely to have fitted it just right.

The handbrake explanation would be true all the time, not just shifting under full power. If things weren't moving then why the difference?

It seems to be better than the normal Griff's change. If these mounts do improve the change then others who have fitted them should have a similar experience.

I'm hoping that I have stumbled on something. Years ago I was involved in turboing a car. The extra torque was flexing the engine on its mounts and the gear change was dreadful compared to before the turbo.

It broke the mounting and we fitted stronger mounts. The gearchange went back to being smooth.

Edited by Uncle Fester on Monday 20th October 18:56

Yellabelly

2,258 posts

283 months

Monday 20th October 2008
quotequote all
Uncle Fester said:
HRG said:
Your old clutch was probably toast.
Not according to Rob at V8D.

But he is likely to have fitted it just right.

The handbrake explanation would be true all the time, not just shifting undercarrage full power. If things weren't moving then why the difference?

It seems to be better than the normal Griff's change. If these mounts do improve the change then others who have fitted them should have a similar experience.

I'm hoping that I have stumbled on something. Years ago I was involved in turboing a car. The extra torque was flexing the engine on its mounts and the gear change was dreadful compared to before the turbo.

It broke the mounting and we fitted stronger mounts. The gearchange went back to being smooth.
I have been through much the same episode with my 500, at V8D and they also fitted a new clutch and poly mounts. Can't say I have noticed a difference in the ease of shifting but I'll give it a run tonight to check and report back drivingcloud9.

Johno

8,593 posts

312 months

Monday 20th October 2008
quotequote all
spend said:
HRG said:
Your old clutch was probably toast.
Spoilsport!

ETA: Is it possible to get the engine out without disturbing the box anyway?

Edited by spend on Monday 20th October 12:43
I took the engine out of mine without removing the gearbox, but you do need to support the box from underneath.

Yellabelly

2,258 posts

283 months

Monday 20th October 2008
quotequote all
Uncle F, I can't truthfully say that it is any easier on the gear shifts. It is, lets say, firm but positive without resisting the change.
YB

Uncle Fester

Original Poster:

3,114 posts

238 months

Tuesday 21st October 2008
quotequote all
Yellabelly said:
Uncle F, I can't truthfully say that it is any easier on the gear shifts. It is, lets say, firm but positive without resisting the change.
YB
That's a pity.

I'm assuming yours is a T5 box.

Griff's gear change were never that quick by reputation.

It would have been nice to have stumbled onto a simple fix.

So what improved my shift?

scratchchin

HRG

72,863 posts

269 months

Tuesday 21st October 2008
quotequote all
Your old clutch was probably toast.

Uncle Fester

Original Poster:

3,114 posts

238 months

Tuesday 21st October 2008
quotequote all
HRG said:
Your old clutch was probably toast.
Is there an echo in here?

in Here? hehe;

When V8D strpped it they said the clutch was in good order and could be refitted.

However, it was about 50% worn. As the cost of replacing a clutch is mostly labour, it made sense to fit the new clutch. Besides which the uprated clutch would take the extra power much better.

HRG

72,863 posts

269 months

Tuesday 21st October 2008
quotequote all
hehe

I'd always replace the clutch and release bearing as a matter of course if the engine and box are apart.

If nothing is immediately obvious I'd say in your case it was the gearbox being pulled about during the engine out that loosened something that was partially binding.

rev-erend

21,622 posts

314 months

Wednesday 22nd October 2008
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It says new clutch ... that is probably the reason.

They might also have fiddled with the gearchange mechanism if they thought it was incorrect and thought it too small and not worth charging for.

trackcar

6,453 posts

256 months

Wednesday 22nd October 2008
quotequote all
the remote linkage rod that runs across teh top chasis rail can get bent by hamfisted fitters, so maybe V8D recognised this and straightened it on your car? its a very common cause of stiffness in the fore-aft plane (but not across the gate where it has no effect) .. sound possible?

Uncle Fester

Original Poster:

3,114 posts

238 months

Thursday 23rd October 2008
quotequote all
trackcar said:
the remote linkage rod that runs across teh top chasis rail can get bent by hamfisted fitters, so maybe V8D recognised this and straightened it on your car? its a very common cause of stiffness in the fore-aft plane (but not across the gate where it has no effect) .. sound possible?
Well, it was always free in neutral, which is most of the side to side.

V8 Racing, if your following this thread did you straighten a bent rod, or notice anything?

The greatest difference is under full, or sometimes just hard acceleration. Driving normally it was just a slow change, but not obstructive.

Previously trying to shift from 2nd into 3rd was quite likely to be unsuccessful if you tried to change quickly.

Having got out of second, you couldn't get into any gear until the revs subsided.

I have seen cars where the torque trys to twist the engine so much that the gearbox twists too, causing the gear lever to move left and right as you blip the throttle.

I imagined that the remote shift was being held still, while the box was being twisted. I may be that this was the case and the remote was trapped. Perhaps proper refitting has allowed it to move with the box, keeping alignment.

Whatever they did, it must have been outside the gearbox itself.

ETA

The previous workshop to have the engine out AFAIK was TVR Power. The engine was rebuilt in 2004 and a new clutch fitted (before I owned the car). I spoke to Dom and he had done the job himself. There's nothing in the history file to suggest it's been apart since and the car has covered about 10k miles since. It's now covered just under 50k since new.

Dom doesn't strike me as the ham fisted type.

Edited by Uncle Fester on Friday 24th October 05:00

Yellabelly

2,258 posts

283 months

Thursday 23rd October 2008
quotequote all
Uncle Fester said:
trackcar said:
the remote linkage rod that runs across teh top chasis rail can get bent by hamfisted fitters, so maybe V8D recognised this and straightened it on your car? its a very common cause of stiffness in the fore-aft plane (but not across the gate where it has no effect) .. sound possible?
Well, it was always free in neutral, which is most of the side to side.

V8 Racing, if your following this thread did you straighten a bent rod, or notice anything?

The greatest difference is under full, or sometimes just hard acceleration. Driving normally it was just a slow change, but not obstructive.

Previously trying to shift from 2nd into 3rd was quite likely to be unsuccessful if you tried to change quickly.

Having got out of second, you couldn't get into any gear until the revs subsided.

I have seen cars where the torque trys to twist the engine so much that the gearbox twists too, causing the gear lever to move left and right as you blip the throttle.

I imagined that the remote shift was being held still, while the box was being twisted. I may be that this was the case and the remote was trapped. Perhaps proper refitting has allowed it to move with the box, keeping alignment.

Whatever they did, it must have been outside the gearbox itself.
Sounds like a problem with the release bearing the resistance between 2nd and 3rd would suggest clutch drag which you almost confirm with the resistance experienced when trying to change quickly and the fact that your remote shift was free from side to side. Fitting the new clutch plate and release bearing has cured the drag.
I saw my car several times down at V8D and the gearbox was left in place until the engine was re-fitted, as far as I am aware Rob did not do anything other than clean out the bell housing and then fitted the clutch, bearing and engine.
YB

Peter66

119 posts

238 months

Thursday 23rd October 2008
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I replaced one of my worn engine mounts recently and also experienced a better gear shift! I had a problem with changing from 4th to 5th and sometimes it dropped out of 5th. It's much better now, but it needs re-alignement of the spring, because it does not center exactly in the middle of 3d/4th. I can imagine that old/worn bushes lead to lowering the engine/gearbox (certainly true in my case, because the engine dropped to one side and the manifolds nearly touched the side panel). As a result the remote gear linkage doesn't move as free as it should. The same might happen with soft/old bushes under power.

Peter