289 build

Information about builds and rebuilds, post away!
Post Reply
User avatar
clive
T289R Member
T289R Member
Posts: 3392
Joined: Thu Mar 01, 2007 1:18 am
Location: Perth

Re: 289 build

Post by clive »

Thinking back, Allan Tunstall had problems grounding out in dips in the road, and following him it was obvious that his suspension was too soft. Stiffening the shocks cured the problem.
Cheers, Clive.

(If I'm not here I'm in my workshop or on the golf course!)
User avatar
amulheirn
T289R Committee
T289R Committee
Posts: 1207
Joined: Mon May 13, 2013 2:30 pm
Location: Surrey/Hampshire
Contact:

Re: 289 build

Post by amulheirn »

I'll give that a try, thanks. It is definitely the rear clamp at the lowest point that is taking the hits.

I have some polybush spring pads arriving tomorrow and hope to remove a spacer or two.
User avatar
amulheirn
T289R Committee
T289R Committee
Posts: 1207
Joined: Mon May 13, 2013 2:30 pm
Location: Surrey/Hampshire
Contact:

Re: 289 build

Post by amulheirn »

Okay - I am befuddled...

I removed the two packers on the passenger side, put it all back together and then measured the top of the wheel rim to the wheel arch on both sides. On the passenger side the distance is 7 1/8", and on the drivers side, 7 1/2". This was after bouncing the back end up and down quite a bit to make sure it sat properly.

So instead of raising the car, it has lowered it by 3/8". The packers added up to 3/4".

What I *should* have done of course is measure that distance on the passenger side *before* I spent an evening sweating my berries off in a concrete garage that had been heated up by the sun like some kind of infernal storage heater. Needless to say, I'm now on the sofa having a cold beer.

What are your thoughts?

Here's my drawing - the spring is effectively part of the chassis, being fixed at each end. That hasn't changed.

The distance from the centre of the axle to the edge of the tyre hasn't changed of course either. All that has happened is that I've moved the axle closer to the spring

The side I took the packers out of was the side that almost always grounded over depressions and bumps. So I wonder if a possible explanation might be that I have assembled one side incorrectly? That said, there's not much you can do wrong - the front end of the spring has to go in the upper hole because the lower one is for the anti-tramp bars isn't it?

More investigation required...
drawing.jpg
You do not have the required permissions to view the files attached to this post.
User avatar
amulheirn
T289R Committee
T289R Committee
Posts: 1207
Joined: Mon May 13, 2013 2:30 pm
Location: Surrey/Hampshire
Contact:

Re: 289 build

Post by amulheirn »

Well I checked with Gerry and he said the packers were optional - included to lower suspension if required. Removing them would raise the car. I really, really, REALLY should have measured before making the change. Fffff...fiddlesticks.

Anyway - my better half has invited a government-approved number of female friends to our patio tonight. They are drinking mojitos, so I took a mojito down to the garage to do the other side.

I decided that measuring wheel-arch to floor through the centre of the spinner was better - but as I type this that is obviously nonsense because differing tyre pressures from one side to the other might affect things. Rim to arch was probably better. But of course on this second visit to the problem I didn't do the rim to arch measurements - only floor to arch. :(

Ultimately, the proper thing to do is compare the same side with the same side - not left against right. I think the only way to solve this is put the packers back in (or sod it and see how it drives!).

Anyway, after tonight's work, measuring arch to floor I got this:

Starting point:
  • Near side (packers removed) - 27 1/2"
  • Off side (packers still in) - 27 3/4"
After removing off side packers:
  • Near side (packers removed) - 27 3/4"
  • Off side (packers removed) - 28 3/8"
So on the off side, the car has definitely risen by almost the height of the packers. And the nearside (unchanged this evening) has gained a quarter inch. Gerry is (or course) right - removing the packers raises the car.

All this means the care probably rides 3/4" higher than it did before so that may make enough difference to stop the sparks at the rear.

Maybe the weather will improve to give it a try tomorrow...
User avatar
Dave Woodward
T289R Member
T289R Member
Posts: 912
Joined: Sun May 06, 2007 10:00 pm
Location: Cheshire
Contact:

Re: 289 build

Post by Dave Woodward »

Very precise work Andy.

All I know is I can get two fingers under the arch on both sides 👉.
__________________________________
I say, ding dong!
User avatar
StewbieC
T289R Committee
T289R Committee
Posts: 1356
Joined: Mon Oct 13, 2008 12:50 pm
Location: out in the sticks, Shropshire

Re: 289 build

Post by StewbieC »

Hi Dave,
You've also got lovely Avon tyres that are a bigger diameter to Blockleys, Verdestein classics and Pirellis so your ride height will be slightly higher and gap to the top of the wheel arch may be smaller by default.
Great work Andy,
It won't completely solve the problem but it will certainly be better. One way is to increase the length of the bump stops and perhaps fit MGB ones which will give a cushioned stop rather than allowing for the exhaust clamp to spark out. I had to replace one of my clamps as it wore through.
________________________________________________
Stu
Hawk 289, 66 Mustang Fastback with a 289 maximum smiles per mile..
User avatar
peterc
T289R Member
T289R Member
Posts: 2041
Joined: Wed Mar 05, 2014 9:05 am
Location: Surrey

Re: 289 build

Post by peterc »

Don’t assume that the two wheel arches are exactly the same height and curvature both sides. Perhaps other 289 slab side members can advise if theirs are similar dimensions. I have checked my FIA and they are reasonably the same but I know that the headlights for example are a fair bit different in height. Moulds would have been taken off an original (potentially repaired) car and of course they were all hand made anyway.
Get the chassis level and then conduct a corner weight check with suitable ballast on the drivers seat.
Peter C
User avatar
amulheirn
T289R Committee
T289R Committee
Posts: 1207
Joined: Mon May 13, 2013 2:30 pm
Location: Surrey/Hampshire
Contact:

Re: 289 build

Post by amulheirn »

IMG_0494.jpeg
Finally painted, and with most of the bits re-attached, my 289 managed to pass its first MOT today! Not sure where the time has gone, but still, its good to know it passes inspection. Off to Goodwood on Saturday!
You do not have the required permissions to view the files attached to this post.
User avatar
Dave Woodward
T289R Member
T289R Member
Posts: 912
Joined: Sun May 06, 2007 10:00 pm
Location: Cheshire
Contact:

Re: 289 build

Post by Dave Woodward »

Looking sweeeeet!
__________________________________
I say, ding dong!
User avatar
clive
T289R Member
T289R Member
Posts: 3392
Joined: Thu Mar 01, 2007 1:18 am
Location: Perth

Re: 289 build

Post by clive »

Lovely period colour! :D
Cheers, Clive.

(If I'm not here I'm in my workshop or on the golf course!)
Post Reply