Prawn and BigAls A3 Track Car

Gops is right.
You need a Renault avantime
 
  • Like
Reactions: Prawn
I give up.

Spent all day on this clunk, reinforced the subframe with 3mm plate around the wishbone mounting holes, redid the subframe mounts with a custom poly sleeve between the bolt and mount, bonded the solid bushes into the subframe to remove ANY chance of any movement.

Everything is done up so tight. i can't make ANYTHING move with the wheels off the deck, yet it still clunks as SOON as I pull forward, then clunks back when I touch the brakes.

It's not a big clunk, but I can hear / feel it still.

It does it regardless of drive situation, in gear, out etc etc.

It's definitely suspension related, you replicate the 'acceleration clunk' by braking in reverse. It's something moving one way when the wheels are loaded up in either direction, this makes me think it's not engine mounting / dog bone movement.

it's driving me insane.
 
Im getting a very similar issue. Mine clunks when touching the brakes and then it clunks again when letting off. Also clunks sometimes when pulling away after brakeing. Its also doing my head in but havent had the time to look into it :(
 
You will sort it mate. Still a pita though. You tackle it alone?
 
MARC87 said:
Im getting a very similar issue. Mine clunks when touching the brakes and then it clunks again when letting off. Also clunks sometimes when pulling away after brakeing. Its also doing my head in but havent had the time to look into it :(
Click to expand...

Hmmmmmmmmmmmmm

Tough one mark.

I've had clunks before on acceleration and let off, and they've been engine mount / dog bone related.

This one very much NEVER happens when letting off though, and only on application of the brakes, then first touch of throttle after that, hence me being absolutely certain it's suspension related on this occasion.
 
Not as tight as you for not changing them bolts!
Lol
 
  • Like
Reactions: StaceyS3 and Prawn
just catching up...

Prawn said:
We have an 02M 6 speed box fitted these days, with a peloquin ATB LSD fitted with APR bolts. The clutch is a 6 paddle ceramic plate with an uprated pressure plate, all mounted to a lightened single mass steel flywheel :)

It's going very well so far. After countless issue on the old 5 speed setup (7 gearboxes!) it seems we've finally got something that's working for us :)
Click to expand...

...do I remember you saying that you also have a heavy duty gear box oil in there now?
 
I had that once prawny.. It was my DV hitting my strut brace lol! Drove me insane! You checked your steering rack bush?
 
Possibly the suspension? My kw v2's used to knock, was shocking, ended up been the coil over itself, had to buy a new one. Stopped it for ages then its come back, think im going to ditch them and try something else.
 
I'm thinking that too Dani. Going to look into having the front struts rebuilt as they've seen some service now.
 
put the car on a 1 man testing mot ramp (shaker plates) this will shake the car around whilst on the ramp and will usually show any failing suspension components, you can also have a good feel of moving parts like the shocks,antiroll bar to try and track down the knocking
 
Have you thought about checking around the brakes dude? Not long since you have installed this new set up....loose bolt maybe or play has appeared somewhere?
Just an idea seen as it's one of the last things you have done?
The cars looking awesome by the way dude! I don't comment much but constantly keeping upto date on your thread! Keep it up!
 
  • Like
Reactions: Prawn
scott_159 said:
put the car on a 1 man testing mot ramp (shaker plates) this will shake the car around whilst on the ramp and will usually show any failing suspension components, you can also have a good feel of moving parts like the shocks,antiroll bar to try and track down the knocking
Click to expand...

That's a great idea. thanks Scott. I might look into that and see if I can find one locally.


Golfyste said:
Have you thought about checking around the brakes dude? Not long since you have installed this new set up....loose bolt maybe or play has appeared somewhere?
Just an idea seen as it's one of the last things you have done?
Click to expand...

Good idea mate, but sadly I checked the brakes over at the weekend whilst it was all apart and it all seemed fine. if it did it just on braking back and forth I'd suspect pads moving in the calipers, but this does it when acelerating then braking going forwards, so braking rotation remains constant but the noise still occurs.

I'm 99% sure it's wishbone / strut / top mount related. i went to town on the wishbones this weekend, so I'm pretty much discounting them. Shocks and top mounts left to eliminate.
 
Last edited:
That's a bit of a weird one. I have an annoying clunk that I think is my top mounts. I suspected struts at first so took them in to be rebuilt and re-greased but it made no difference. Mine is more of knocking over certain types of bumps and only on one side. I'm pretty sure mine's the top mounts, just not sure how to fix it.
 
Hi prawn just to add to this I also have said clunk it's so annoying I've changed everything other than drive shafts wonder if it could be those?
 
I can only say what I said before. My wishbone bolts were tight, and the way they work, they aren;t a stretch bolt, but the instant I replaced them, the clunk I had was gone
 
vroomtshh said:
I can only say what I said before. My wishbone bolts were tight, and the way they work, they aren;t a stretch bolt, but the instant I replaced them, the clunk I had was gone
Click to expand...

Fair enough Garry. I'll try it. Will change them over this weekend and see what happens!

Thanks mate. At least it's a cheap solution so no loss if it doesn't work!
 
  • Like
Reactions: Essflee
As you've replaced them recently Garry, you don't happen to know the torque spec of the wishbone bolts do you?

and perhaps the subframe bolts! I might buy a set of those too.

I'm ashamed to admit, I actually stripped the thread in the rear drivers side subframe bolt. Too keen to over tighten thing to make the noises stop :( Pretty gutted about it to be honest, but thankfully it's easily accessed from behind, and a front subframe bolt is easily long enough to go up through and put a big nut on the inside.

Bit of a fail there, but oh well.
 

1. Subframe retaining brackets (on body)
2. Welded nut (in body)
3. Rear bonded rubber bushing for subframe
4. Nut, self=locking (always replace)
5. Bolt (always replace, tighten to 100Nm or 74ft/lb + 1/4 turn or 90 degrees)
6. Rear bonded rubber bushing for control arm (press in/out)
7. Bolt (always replace, tighten to 70Nm or 52ft/lbs + 1/4 turn or 90 degrees)
8. Nut plate
9. Nut, self-locking (always replace, tighten to 45Nm or 33ft/lb)
10. Ball joint
11. Bolts (always replace, tighten to 20Nm or 15ft/lb +1/4 turn or 90 degrees
12. Control arm
13. Stabilizer connecting link
14. Bolt (tighten to 45Nm or 33ft/lb)
15. Stabilizer bar (subframe must be lowered to remove and install)
17. Bolt
18. Bolt (always replace, tighten to 100Nm or 74ft/lb +1/4 turn or 90 degrees
19. Front bonded rubber busing for control arm
20. Bolt (always replace, tighten to 70Nm or 52ft/lb +1/4 turn or 90 degrees
21. Bolt (always replace, tighten to 50Nm or 37ft/lb +1/4 turn or 90 degrees
22. Bolt (always replace, tighten to 50Nm or 37ft/lb +1/4 turn or 90 degrees
23. Pendulum support
24. Bolts (always replace, tighten to 25Nm or 18ft/lb +1/4 turn or 90 degrees
25. Stabilizer bar bushing
26. Stabilizer bar mounting bracket
27. Bolt (tighten to 25Nm or 18ft/lb
28. Subframe (if damaged, do not repair threads in sub-frame for front control arm bolt)
 
Nice one Garry, I'll call the local chinese takeaway tonight:

Can I have 1x number 5, 3 x number 18, 2 number 7's, 2 number 4's, and 2 number 20's please, and a chicken fried rice!
Click to expand...
 
There was a slight clucnk on mine going uneven roads Nick, turned out to be a worn steering rod, the play was minimal, but a hunter machine detected it, replaced and no more clunking. Worth a look?
 
Cheers Joe. I'll check them all out again on saturday when I change the bolts on the front end. it HAS to be something simple!
 
Cheeky question: Does anyone have a copy of ETKA that could give me part numbers for some of the above?

Parts, 5, 18, 7, 4, and 20 if at all possible! My local TPS are OK, but prefer part numbers and get angry if I make them search!
 
On a side note, the ramp idea didnt work for me, even had it on a mot test ramp with the hydro lift, wasnt until I took them off and inspected them.

Good shout on the track rod jo.
 
A knackered trackrod becomes floppy like the pic below, a good one can hold itself straight in the air. And my one was only 60k miles old.

27F269FD-0D9E-4671-969C-2EC254ACE882-3352-00000239B9270B86_zps33d572ae.jpg
 
  • Like
Reactions: Dani_B19
I can't really suggest anything you won't have already checked Nick, my only additional idea would be to mark the bolt heads/nuts/bush sleeves/solid mounts with something like torque seal. Just a quick line down them onto what they're bolted to. I know they're not loosening so probably aren't rotating (or at least if they are, they're rotating back), but the proper paint's thick and brittle, so it's obviously cracked if something's moved at all, even if it's just shifted fore/aft a fraction of a mm. It should show up any movement, or at least put your mind at rest about things that aren't by providing some solid proof that they really aren't.

Do your KW's use an inverted damper with a bush in the strut body? If so, it's a lovely stiff design but does seem more prone to wearing out the bush than normal dampers. Definitely worth checking anyway, the rally car needed them doing at the start of this season.

Also, I take it you've checked the rear beam bushes/mounts? Just in case.
 
Right so when replacing the wishbones this needs tobe replaced?
 
Dani_B19 said:
Right so when replacing the wishbones this needs tobe replaced?
Click to expand...

Audi/VW say so. I can;t really understand why, as its a nut and bolt. So its not stretch or anything, but its definitely what they recommend, and did make a difference for me
 
  • Like
Reactions: Dani_B19
£35 spent on bolts at TPS today, all new bolts for the front subframe and wishbones.

Will throw them on on Saturday morning :) and see what happens!
 
You must log in or register to reply here.

Similar threads

J
A3/S3 Track car...
Replies
26
Views
8K
Prawn
Prawn
jsmotorsport
audi a3 8L track car
Replies
6
Views
4K
Prawn
Prawn
Marzo_NO
My A3 quattro track car
Replies
10
Views
4K
badger5
badger5
Sootpig
Sootpig's A3 track/drag car
Replies
166
Views
20K
Erikn89nl
Erikn89nl
M
S3 or A3 Track car?
Replies
40
Views
4K
Murf
M
Top
Back