proof of power increace over factory for WOF?

[QikStarlie]

you need a cert because you have changed the cylinder head. Its in the rules somewhere.

No you don't, and no its not

depends how you read f:



20v different design and casting to 16v

[ChaosAD]

Yea but according to the wof rules in the link I posted the new engine also has to be the same or less power of the standard engine.

So im going for the 'modified version of the OE engine' route.

[Lloyd]

The cert rules and the VIRM don't word it is entirely the same. Going by the warrant rules I would take it as meaning any 4A head is allowed on any 4A block with no cert. Going by the cert stuff you posted upt hen I would take it as meaning it needs a cert. But I do WoFs, so it would be fine lol





Cert not required provided that:
• when compared with the OE engine, the replacement engine:
– is of the same or less cubic capacity, and
– has equal or less weight, and
– has the same or less power output, and
– uses the same fuel (petrol, diesel, LPG, CNG), and
– uses the same unmodified attachment points and system
(ie, bolts-in), and
– uses the same ancillary equipment (accelerator linkages etc), and
– uses the same family of block and cylinder head from the same vehicle manufacturer, and
– is of the same configuration.


• the modifications result in not more than 20% more power than the OE engine, which may
include the fitting of:
– extractor or free-fl ow exhaust manifolds, or big bore exhaust systems
– changed intake manifolds
– changed or multiple carburettors
– modified fuel injection systems
– changed ignition systems
– alternative cold air box induction systems.
• see Note 2.


Note 2 LVV certification is always required for the fitting of a supercharger or turbocharger as a modification, or
the substitution of a turbo or waste-gate, or the re-chipping of electronic engine control units on turbo cars.

[QikStarlie]

interesting. any other contradictions or "loop holes" we should know about ?

[ChaosAD]

I wouldn't call it a loophole.

Your referring to an engine transplant but lloyd is referring to modding the stock engine.

You can fit the 20v head to a 16v engine but if you break the 20% power increase threshold you need a cert.

If you replace a 16v with a 20v your making more power tha stock so need a cert.

[levinguy]

what is 'of the same configuration' mean?

im sure some wof inspector would interpret a 20valve head vs a 16v head being of different configurations?

[QikStarlie]

yeh i was meaning in general.

also as levinguy says the wof one seems petty vague as well.

[Lloyd]

Same config means inline 4, 6, V8, flat 4 etc etc


Thats just extract from the modifications bit about engines and drivetrains. If you want to read the whole thing then set yourself aside a fair bit of time

[NZ_AE86]

I would say you need cert as you have changed the head.

You are allowed to do minor mods and not exceed 20% more power
The mods you are allowed to do are:

– extractor or free-fl ow exhaust manifolds, or big bore exhaust systems
– changed intake manifolds
– changed or multiple carburettors
– modified fuel injection systems
– changed ignition systems
– alternative cold air box induction systems.



The rules say these are the mods you may do. In my opinion you have gone beyond these mods and need cert.

[fivebob]

I would say you need cert as you have changed the head.
...
The rules say these are the mods you may do. In my opinion you have gone beyond these mods and need cert.

No the rules do not say that. What they say is

• the modifications result in not more than 20% more power than the OE engine,which may include the fitting of:
...

The second part of that sentence is just giving examples of modifications that should result in less than 20% power gain. It is not giving a definitive list of the allowed modifications. If it was a definitive list then there would be no need for the Note 2 which states:

Note 2 LVV certification is always required for the fitting of a supercharger or turbocharger as a modification, or the substitution of a turbo or waste-gate, or the re-chipping of electronic engine control units on turbo cars.

[NZ_AE86]

If I was doing the WOF I would want the car to be cert'd.

As I have to sign the page to say that the car fits within the rules I like things to be clear!

[deaf_rattle]

you need a cert because you have changed the cylinder head. Its in the rules somewhere.

No you don't, and no its not

ok

[DRFTIN]

haha no matter how its worked its a pointless law. they gonna put a dyno run on each wof?
wheni had my cert plate fitted i was talking to the guy about the car and telling him how it had double the factory power and that sure wasnt on the plate

[Leon]

Do you want insurance to actually pay out if you drive the car into a Merc?

If yes, then cert it. Don't piss about.

[ChaosAD]

Why when it doesnt need a cert. The silvertop allegedly puts out 23% more power than a bluetop.
Im sure a tired 16v with a silvertop head/intake exhaust wont put out the same power as a silvertop.

A dyno run is a waste of time/money as you can tweak it to give you the readings you want.

Where does it say in the rules you need a cert for a cyl head change?? aslong as its under the 20% threshold.

[NZ_AE86]

Is the car in question a standard road car apart from this head?

[ChaosAD]

The exhaust reduces down to the factory 2" for part of the way then opens up to 2 1/4" (standard silvertop is 2 1/4").

Rear seats/belts removed
Sound deadening removed
king lowering springs
koni&munroe shocks
urethane bushes all round
whiteline rear swaybar

I have adjustable platform suspension waiting to be fitted and am planning to fit twinpot brakes, halfcage (rollbar), race seats etc and will get it certed after everything is done.

I dont want to get it certed at this stage as I will need to get it re-certed once the rest of the work is done.

[JT]

Just take it to a different place.

I made the mistake of going to a cheaper garage who had a coupon in the yellow pages, quoted me $800 to fix things to bring it to WOF standard.

One of the things they said was the wipers didn't clear all of the water in the first couple of swipes. Was just cos it was dusty and the water didn't flow off well first time. Said exhaust was too loud, number plate lights too dim and control arm bushes perished (still ok though)

Went to a WOF only place, didn't bring up ANY of the issues.

[NZ_AE86]

So if I purchase your car, decide that I want to modify my new car by replacing the block/crank/rods and pistons with those from a 20Valve engine, do I need to get the car certified if it is still under 20% more power then the factory engine?

I have 2 dyno sheets from a 4AGE - Bluetop 77kw ATW and Silvertop 20V 83kw ATW which should cover the paperwork side of things.

The vehicle now has a new engine that would require cert if it was put in as one part(required to have the same or less power ouput). But if installed in two 'installments', does this change the rules?

Also, how long do I need to have a vehicle going with the new head before I can add the new block etc? Is doing it on the same day a no no?

The more I think about it the more I stand by the fact it needs cert.

[RomanV]

You need a cert for change of ECU...

So could you even run the 20V head with standard 16v ECU anyway?

If so, would it even be worthwhile to do so?

If not, then technically I guess you need a cert for the changed head, via required change in ECU.

I seriously doubt that anyone's ever been pinged for having an uncerted ECU change though