Engine Undertray Damaged? Jules Tip Read This!

Jules · 4th November 2007, 17:59

If any ZT 260 owners (75 V8's unaffected) fed up of damaging their undertrays.
No matter how slowly I drive over some of the speed bumps around here, due to the little ground clearance, the undertray gets a hammering.

Well you might welcome this tip/mod.
The recent trip up to Holker Hall resulted in us following JDC's smoke rather than leading him (we couldn't go over 65 MPH due to most of the undertray fixings being damaged at some point earlier.)

We did stop at one point to do a temporary repair using those very large size cable ties! Due to the immense down force on these undertrays even at moderate speeds, the tie wraps soon got torn right through.

I have waited six weeks to post this modification just to make sure it survived the test of time and a few miles. Simply replace the large undertray with one from a ZT 1.8T. They are 1/3 the size and don't get hit.
Ok the subframe might get the odd scratch but at least nothing breaks now

These undertrays are on ebay now £35 Brand new and work a treat.:
New one on the left even comes complete with the front edge clips and the 1/4 turn Screws (normally 2 quid each!)

TimO · 4th November 2007, 18:51

Hi Jules, would this shortened tray work on a CDTi ZT? as it would make servicing a whole lot easier and quicker.

Cheers

Tim

Jules · 4th November 2007, 23:44

Hi Tim
Not sure on that one, think some of the contours are different.
Try and look on the pictures as I think Best of British Rover is selling both types at the moment
The main differences on the diesel undertray are soundproofing package is attached and the fixings are ALL 1/4 turn screws.

Where as on the petrol variants the rear 4 fixings are 13mm bolt heads.
This difference wouldn't matter of course on the smaller tray.

Not a recommended mod though Tim as the diesels are quite a lot noisier without the proper undertray fitted. I noticed straight away when my local garage had forgotten to refit one after a service.

Keith · 5th November 2007, 11:29

Don't forget Rincewind has said the undertray has an aerodynamic value as well especially at speed on the V8
So maybe refit the original if going on an Autobahn run or a track day type trip

VXman · 10th November 2007, 18:12

Given the wieght of the V8 undertray you'd probably improve performance and fuel consumption too!

4th November 2007, 17:59	#1
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	Engine Undertray Damaged? Jules Tip Read This! If any ZT 260 owners (75 V8's unaffected) fed up of damaging their undertrays. No matter how slowly I drive over some of the speed bumps around here, due to the little ground clearance, the undertray gets a hammering. Well you might welcome this tip/mod. The recent trip up to Holker Hall resulted in us following JDC's smoke rather than leading him (we couldn't go over 65 MPH due to most of the undertray fixings being damaged at some point earlier.) We did stop at one point to do a temporary repair using those very large size cable ties! Due to the immense down force on these undertrays even at moderate speeds, the tie wraps soon got torn right through. I have waited six weeks to post this modification just to make sure it survived the test of time and a few miles. Simply replace the large undertray with one from a ZT 1.8T. They are 1/3 the size and don't get hit. Ok the subframe might get the odd scratch but at least nothing breaks now These undertrays are on ebay now £35 Brand new and work a treat.: New one on the left even comes complete with the front edge clips and the 1/4 turn Screws (normally 2 quid each!) __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

4th November 2007, 23:44	#3
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	Hi Tim Not sure on that one, think some of the contours are different. Try and look on the pictures as I think Best of British Rover is selling both types at the moment The main differences on the diesel undertray are soundproofing package is attached and the fixings are ALL 1/4 turn screws. Where as on the petrol variants the rear 4 fixings are 13mm bolt heads. This difference wouldn't matter of course on the smaller tray. Not a recommended mod though Tim as the diesels are quite a lot noisier without the proper undertray fitted. I noticed straight away when my local garage had forgotten to refit one after a service. __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

4th November 2007, 18:51	#2
TimO Loves to post ZT CDTi+ & Rover 75 Tourer CDTi Join Date: Nov 2006 Location: Old Colwyn Posts: 441 Thanks: 0 Thanked 3 Times in 3 Posts	Hi Jules, would this shortened tray work on a CDTi ZT? as it would make servicing a whole lot easier and quicker. Cheers Tim

5th November 2007, 11:29	#4
Keith This is my second home ZT400 Join Date: Oct 2006 Location: Ellesmere Posts: 5,948 Thanks: 0 Thanked 43 Times in 29 Posts	Don't forget Rincewind has said the undertray has an aerodynamic value as well especially at speed on the V8 So maybe refit the original if going on an Autobahn run or a track day type trip

10th November 2007, 18:12	#5
VXman Regular poster MG ZT -T 260 Join Date: Nov 2006 Location: Milton Keynes Posts: 73 Thanks: 0 Thanked 8 Times in 3 Posts	Given the wieght of the V8 undertray you'd probably improve performance and fuel consumption too!