CERT FOR 3"-4" LIFT

mudhunt · Post by **mudhunt** » Sun Aug 12, 2007 4:11 pm

Hey ive just raised my swb safari, 3.5" lift springs rancho 9000,s drop boxes and extended strengthened trailing arms. Who has a cert for their lift? are drop boxes all good for certification? Or does no one have a cert for their lift

Post by **Mark** » Sun Aug 12, 2007 8:38 pm

I have to certify my 2" body lift, so you'll definitely have to cert that with the drop boxes and trailing arm mods.

I remember when I was scouring the LTSA WOF manuals and stuff that there was definitely talk of suspension mods, but couldn't see anything about body lift mods. But when I called the local certifiers they were both in no doubt that I would have to cert it.

If in doubt just ring a certifier.

DaveM · Post by **DaveM** » Sun Aug 12, 2007 8:49 pm

Because the drop boxes change the factory mounting position of the radius arms they need to be certed, the extended trailing arms will too.
If you are considering a body lift in the future, do it now to save having to re-cert. Its also not a bad idea to borrow a set of 35's for the cert if you can, for the same reasons.

mudhunt · Post by **mudhunt** » Sun Aug 12, 2007 9:16 pm

good point i was planning on 35"s. So did you have a similar setup? Did you get a cert easily enough with drop boxes?

DaveM · Post by **DaveM** » Sun Aug 12, 2007 9:24 pm

Mine got a wof without having to cert, and I havent got round to certing it.
I'm putting it back to 3" and removing the panhards etc so I don't have to sert it when I sell it.

Currently has 4" lift with drop boxes and custom trailing arms and panhards.

wjw · Post by **wjw** » Mon Aug 13, 2007 8:22 am

DaveM wrote:If you are considering a body lift in the future, do it now to save having to re-cert. Its also not a bad idea to borrow a set of 35's for the cert if you can, for the same reasons.

Once its cert'd with 35's you aren't allowed to have any other tyre size than 35's and can only use the size rims you had on at cert time, or factory rims with 35's.

mudhunt · Post by **mudhunt** » Mon Aug 13, 2007 10:16 am

really thanks for the tip i would have thought though that you would be able to have any size on that is smaller than the cert? cheers

doby · Post by **doby** » Mon Aug 13, 2007 11:29 am

How about a 2" spring lift, gota sert that?

mudhunt · Post by **mudhunt** » Mon Aug 13, 2007 11:35 am

2" suspension lift is fine from what ive been told. Just anything over or any body lifting

DaveM · Post by **DaveM** » Mon Aug 13, 2007 11:57 am

Local certifier said that at the moment there is no tyre size recorded on the cert plate, just rim size.
Said that if I cert my 35's, then running 33's is no problem as the braking/steering etc on a 33" tyre would be the same, if not better than a 35 so said there is no problem certing a bigger tyre, as thats what a lot of comp guys do when travelling to events

doddzee · Post by **doddzee** » Mon Aug 13, 2007 7:11 pm

My cert plate only has rim size on it. Looked over what the certifier put down on his forms and there was no memtion of tyre size on it either.

wjw · Post by **wjw** » Mon Aug 13, 2007 9:34 pm

doddzee wrote:My cert plate only has rim size on it. Looked over what the certifier put down on his forms and there was no memtion of tyre size on it either.

Tyre size is on the forms for mine, rim size only on plate. Reason behind it is the speedo will be out if you change tyre size, its that 5% rolling diameter thing. Just cos you've got a cert doesn't change the rules. Although from what I can tell, it only change in the last 6 months or so. Last time I enquired it was fine.

We took my factory alloys with 31's on along, with the 35's on the truck and he said sorry can;t do that anymore. I'd heard he might put both sets on cert docs, but no :-(

ahh well.

mudhunt · Post by **mudhunt** » Mon Aug 13, 2007 9:38 pm

the whole cert thing seems very unclear to me?.?

wjw · Post by **wjw** » Mon Aug 13, 2007 9:42 pm

mudhunt wrote:the whole cert thing seems very unclear to me?.?

You need to call the certifier who is actually going to do the cert on your truck as its all their 'interpretation' of the rules. Just like your local WOF guy.

Dak · Post by **Dak** » Mon Aug 13, 2007 10:08 pm

wjw wrote:
mudhunt wrote:the whole cert thing seems very unclear to me?.?

You need to call the certifier who is actually going to do the cert on your truck as its all their 'interpretation' of the rules. Just like your local WOF guy.

Hmmm, which is the suck hole part. The whole system is a joke and needs a serious sort out.

Cheers, Jeff.

DaveM · Post by **DaveM** » Mon Aug 13, 2007 10:28 pm

Dak wrote:Hmmm, which is the suck hole part. The whole system is a joke and needs a serious sort out.

Cheers, Jeff.

I agree. I think it would be silly to have to certify one size of wheel only.
If you can get a cert for larger tyres, say 35's, then why shouldn't you be allowed to run smaller?
Thats like saying you can certify a turbo, but you MUST have a turbo to be legal with that cert :roll:

Oh, the certifier I called was in ChCh, as he heads to Blenheim to do the local certing as we don't have one here.

BIG_BOY · Post by **BIG_BOY** » Mon Aug 13, 2007 10:39 pm

the tyre bit is cos they check your spedo with 35`s so it must me out if you have 31`s but i asked & can get certed for 31,33 & 35`s on the same plate when i finish the circuirt to auilter my spedo signal depending on tyre size

wjw · Post by **wjw** » Tue Aug 14, 2007 8:06 am

BIG_BOY wrote:the tyre bit is cos they check your spedo with 35`s so it must me out if you have 31`s but i asked & can get certed for 31,33 & 35`s on the same plate when i finish the circuirt to auilter my spedo signal depending on tyre size

Thats why he wouldn't let me do it, need to change my speed to electronic ;-)

muskie · Post by **muskie** » Fri Sep 21, 2007 8:08 pm

how much does certifying cost currently

DaveM · Post by **DaveM** » Fri Sep 21, 2007 8:15 pm

muskie wrote:how much does certifying cost currently

Usually $350-400 odd

muskie · Post by **muskie** » Sat Sep 22, 2007 9:18 am

well i wont be bothering with a body lift then, i am an aircraft engineer and understand the need for safety but i dont need to pay someone $400 bucks to tell me i have put some spacers in correctly. maybe i will wait and get it done once i have done all the modifications i want to do.....

xj · Post by xj » Wed Oct 10, 2007 6:59 pm

lvva states that you can lift suspension without a cert providing that factory mounts remain unmodified (shock and spring) and that the vehicle is a minimum of 100mm from the road. It states a minimum distance off the road, but not a maximum, read into that what you will, but its seems pretty clear to me.

Also, my cert plate states rim size, but says nothing about tyre size.

http://www.lvvta.org.nz/CertThresholdSc ... il04V3.pdf
ref page 8 for exact wording of what i have posted above.
ref page 9 for wheel and tyres/hubs and axles

If it is silent on any particular matter, for example, adding new adjustable pannard rods.... then certification is required. The beginning of each chapter has a little disclaimer type comment saying something like "lvv certification is always required for any steering modifications unless stated below"

wjw · Post by **wjw** » Wed Oct 10, 2007 7:13 pm

tyre sizes have been asked about many times which is why I wrote this:

Certification - Tyres

Smurf · Post by **Smurf** » Wed Oct 10, 2007 7:32 pm

I was told they record rim size on the cert plate and also record tyre size on computer so WOF guys etc can access full information

rowinz · Post by **rowinz** » Wed Oct 10, 2007 7:43 pm

the 2" suspension cert thing comes from the statement in the LVV threshold that relates to modifying suspension with blocks fitted between spring and mounts cannot be greater than 2". I've been told this is aimed at the hot rod leaf sprung vehicles with leaves under. Blocks between springs and mounts will lower the body. That is my understanding on that.
That said any alteration to factory mounts of susp parts requires certification.
R

DaveM · Post by **DaveM** » Wed Oct 10, 2007 7:46 pm

I can see why larger tyres need certing, but I find it strange that it is not detailed on the cert plate.
The certifiers I have spoken to say they don't even record tyre size

U-BOAT · Post by **U-BOAT** » Thu Oct 11, 2007 12:00 pm

xj wrote

lvva states that you can lift suspension without a cert providing that factory mounts remain unmodified

yes this is true but talking to the certifer who done my truck you can lift a truck providing the original OEM springs are used. :shock:

Aftermarket springs need to be certed. It sounds stupid and even he doesn't agree with it.

dave m wrote

Thats like saying you can certify a turbo, but you MUST have a turbo to be legal with that cert

actually if you get certed for a say a 2.8 turbo in a hilux and that motor blows up you can fit a 2.2 ( L ). 2.4 (2L), a standard 2.8 (3L) and possiblya 3.0 (5L) with out needing to get re-certed. This is because any increase of 25% in either torque or horsepower needs to be certified. But if you fit a an engine of the same series of block that does not exceed the power ratings of the factory engine, cert is not needed.

dave m wrote

The certifiers I have spoken to say they don't even record tyre size

yeah i agree with you there dave most certifiers don't specify a tyre size. I know that with my cert the speedo was checked using a GPS in open road driving at 50kmh and 100kmh. That was with my truck on 35's, i had altered my diff ratio to suit.

This was only done because my truck is diesel and if affercts the RUC as mileage will be out. If my truck were petrol tyre size doesnt come in to it - so i was told.

i think where the tyres size thing falls down is where you get certed for your rims, not the tyre size and you get pulled up by a traffic cop while your going for a play with your big tyres. If he decides to do a speedo check you will get done because your truck is reading slow,

thus ripping off the government

, on the other hand i can't see a cop giving you a ticket if you get caught on you road tyres anfd you are clocking up too many k's

gary_in_nz · Post by **gary_in_nz** » Thu Oct 11, 2007 5:41 pm

better yet just go off road very quickly if you get chased, i dont think their commodores will be following :evil:

wjw · Post by **wjw** » Thu Oct 11, 2007 7:22 pm

I was told by the guy that certed my truck that the tyre size is specified in the docs, we tried to get my tomotor rims & tyres certed along with the 35's so we supplied both, but no. I have stated the official reasons for this many times, but I'll quote it again:

wjw wrote:It MUST be certed if the rolling diameter is 5% larger than the OE Spec.

Specs:

http://www.ltsa.govt.nz/publications/vi ... s-v2-3.pdf

Vehicle Inspection Requirements manual:

http://www.ltsa.govt.nz/publications/vi ... index.html

Has an FAQ on here thats useful

http://www.lvvta.org.nz/

you can fit any diameter wheel as long as the rolling circumference (the distance one turn of the wheel travels on the road) does not increase more than 5% over the original equipment without the need for an LVV cert. The main reason for this is that a substantially increased rolling circumference will make the speedo under-read (i.e. the speedo will read, say, 90kph when you are doing 110 kph).

Unfortunately what needs certifying isn't always in the WOF book.

The other thing to think about with ANY mods is that your insurance company may not cover you without a Cert.

Rolling Diameter aka Circumference = 3.14 x Diameter

Tyre Size = Circumference

28.9" (235/75R15) = 90.746"
31" = 97.34" == 7.27% Increase in rolling Diameter over 235/75R15
32" = 100.48"
33" = 103.62"
35" = 109.9"

I'm sure you can do the % thing

Its all to do with the speedo.

DaveM · Post by **DaveM** » Thu Oct 11, 2007 7:39 pm

I don't think anyone is saying that the tyres don't need certing, more the fact that a lot of the time there is no mention on the plate or paper work.

My point is, since a cert IS required for tyres larger than 5% rolling diameter, why not specify it on the plate? I have never seen a wof issuer look up a vehicle on the computer.

The certifiers I have spoken to have dont test speedo accuracy when larger tyres are fitted, but only handling and braking performance.

CERT FOR 3"-4" LIFT

CERT FOR 3"-4" LIFT

lift cert