Legally converting na6 to 1.8 in Victoria?
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- Speed Racer
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Legally converting na6 to 1.8 in Victoria?
not sure if this is the right area to be posting this topic...
if i wanted to drop a na8 engine into my na6 and do it 100% legally, what would be involved? i'm talking a stock standard na8 engine, with the standard intake and all that stuff.
there is the flyin' miata conversion kit, which makes it easy, but is it legal? i think that running the 1.8 off the 1.6 ecu would raise legal issues, around emmissions and all that sort of stuff.
or would i have to change the ecu and wiring harness etc, the whole shebang, and get an engineer to sign it off?
if i wanted to drop a na8 engine into my na6 and do it 100% legally, what would be involved? i'm talking a stock standard na8 engine, with the standard intake and all that stuff.
there is the flyin' miata conversion kit, which makes it easy, but is it legal? i think that running the 1.8 off the 1.6 ecu would raise legal issues, around emmissions and all that sort of stuff.
or would i have to change the ecu and wiring harness etc, the whole shebang, and get an engineer to sign it off?
- lightyear
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Legally converting na6 to 1.8 in Victoria?
Why would you want to swap???
NA8B - P.I 1:50.1 Wntn1:38.0 Sand1:27.6 Wntn S1:08 Bfrd1:06.9 Cldr1:08.5 Wak1:10.4
"SE" - P.I 1:43.8 Wntn1:32.9 Sand1:22.0 Bfrd1:05.3
"SE" - P.I 1:43.8 Wntn1:32.9 Sand1:22.0 Bfrd1:05.3
- Hammer
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Legally converting na6 to 1.8 in Victoria?
lightyear wrote:Why would you want to swap???
Short nose crank problems?
H@mmer - 1994 Clubman | 2002 SP

GO TOPLESS!!!

GO TOPLESS!!!
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Legally converting na6 to 1.8 in Victoria?
Hammer wrote:lightyear wrote:Why would you want to swap???
Short nose crank problems?
nope, my current engine is still running fine. reason for swap is simple , bigger engine = more power and torque.
- bruce
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Legally converting na6 to 1.8 in Victoria?
I remember there being a rule that an increase in capacity of X% an engineer certificate is not required.
I would ring VicRoads and ask to speak to an Engineer who can say yay or nay.
I would ring VicRoads and ask to speak to an Engineer who can say yay or nay.
- lightyear
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Legally converting na6 to 1.8 in Victoria?
It seems like a lot of work and money for such a small gain. I looked into it myself. You are better off selling your car and buying an na8. That way you get all the other good bits that come with it like bigger brakes, chassis braces, Stronger box, diff,etc.
NA8B - P.I 1:50.1 Wntn1:38.0 Sand1:27.6 Wntn S1:08 Bfrd1:06.9 Cldr1:08.5 Wak1:10.4
"SE" - P.I 1:43.8 Wntn1:32.9 Sand1:22.0 Bfrd1:05.3
"SE" - P.I 1:43.8 Wntn1:32.9 Sand1:22.0 Bfrd1:05.3
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Legally converting na6 to 1.8 in Victoria?
yeahi hear what you're saying mate, but I already have bigger brakes, chassis braces and torsen diff !
bruce thats a good idea, i'll call vicroads, thanks. but the increase in engine capacity is not the only issue, i'm thinking the ECU / wiring is going to be the biggest headache?
bruce thats a good idea, i'll call vicroads, thanks. but the increase in engine capacity is not the only issue, i'm thinking the ECU / wiring is going to be the biggest headache?
- Jeo
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Legally converting na6 to 1.8 in Victoria?
I'm confident that the engine swap itself will have no dramas being legal, no engineering required, but the other parts could cause concern. Just call the relevant people and get an answer straight from the horses mouth.
Still overall I'd suggest selling your car and buying an NA8 if thats what you want. The amount of cocking about I went through to get my car running properly was just silly.
(damn, lightyear beat me to it. Stupid hitting the reply button then getting distracted by other threads)
Edit: And Fatty already replied too, well aren't I useful
Still overall I'd suggest selling your car and buying an NA8 if thats what you want. The amount of cocking about I went through to get my car running properly was just silly.
(damn, lightyear beat me to it. Stupid hitting the reply button then getting distracted by other threads)
Edit: And Fatty already replied too, well aren't I useful

- StanTheMan
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Legally converting na6 to 1.8 in Victoria?
Isn't Fatty's NA6 a turbo already?
he's probably got an after market ECU to make it work properly.
he's probably got an after market ECU to make it work properly.
Satans Ride called F33nix the resurrected NA6
- mx52nv
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Legally converting na6 to 1.8 in Victoria?
Fatty,
From VicRoads website
So let us say you bought the FM conversion kit, a low kilometre BP motor & was doing the work yourself - the only issue would be if your OEM ECM (factory computer) will be able to run the 1.8 injectors after 5,000 rpm.
A little more info discussed here -> clicky.
Hope this helps.
Les & my disassembled BP motor waiting for pistons & rods.
From VicRoads website
Regarding 1.8 BP conversions, I have some intimate knowledge regarding these.Change of engine
1. Replacement engine is identical to the original engine, or is an option allowed by the manufacturer for the same model vehicle
The optional engine must be offered in Australia by the vehicle manufacturer as an option for that vehicle (or certified variants). The change of engine may be recorded by VicRoads provided that the registered operator or a motor mechanic, or dealer in that make of vehicle or an Automotive Engineer signs a declaration certifying the engine is optional for the vehicle model, and that all modifications made by the manufacturer for the same vehicle model with that optional engine have been completed.
You will need to attend a VicRoads Customer Service Centre to have the vehicle's engine inspected to confirm the new engine details. No appointment is required. You will also need to complete a Change of Vehicle Description form [PDF 24kb].

A little more info discussed here -> clicky.
Hope this helps.

Les & my disassembled BP motor waiting for pistons & rods.

- Matty
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Legally converting na6 to 1.8 in Victoria?
I inquired on this a while ago. It's more than a 10% capacity increase, so technically you need to get it engineered. This would require all of the emissions equipment from the donor car (ECU, fuel system, AFM, intake and exhaust through to the cat - ideally a while wiring loom swap).
On a practical level, you could very likely dump in a 1.8 with the 1.6 running gear, take it to a VicRoads office and have it signed off as a direct swap because they just wouldn't know...
On a practical level, you could very likely dump in a 1.8 with the 1.6 running gear, take it to a VicRoads office and have it signed off as a direct swap because they just wouldn't know...
- mx52nv
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Legally converting na6 to 1.8 in Victoria?
Matty,Matty wrote:I inquired on this a while ago. It's more than a 10% capacity increase, so technically you need to get it engineered. This would require all of the emissions equipment from the donor car (ECU, fuel system, AFM, intake and exhaust through to the cat - ideally a while wiring loom swap).
On a practical level, you could very likely dump in a 1.8 with the 1.6 running gear, take it to a VicRoads office and have it signed off as a direct swap because they just wouldn't know...
I read the VicRoads' rule quite differently. Since the NA8 and NA6 are essentially the same model chassis, the largest engine fitted is the 1.8 BP. Of course, I do not know for a fact if this is correct on Victoria but in WA (so different state so different rules), this is legal. All we do is submit a change of engine (number) form.
Hmmm...there must be someone in Victoria who has done a BP conversion to their NA6 already and can confirm legality and administrative procedure? Unless Matty is talking from actual experience, in which case I will again return to my cave (it is really getting dark in there).

Les
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Legally converting na6 to 1.8 in Victoria?
FWIW, I did a similar thing years ago - swapped a Mazda 323 1.3 litre engine out, and fitted the 1.5. All I had to do was notify QLD Transport of the new engine number. They didn't even inspect the car. Admittedly that wasn't in VIC...
Best part was, I pulled all the emissions junk off (well, some of it fell off, necessitating the removal of the rest) and gained an average of 80kms per tank. I also got pulled over by DOT for an emissions test and they stuck their measuring probe up the exhaust pipe (no cat, unleaded fuel, no emissions gear) and got a "very good to excellent" overall rating!! The inspectors were quite surprised, and impressed! I laughed as I drove away
Glad they didn't want to look under the bonnet though!
Best part was, I pulled all the emissions junk off (well, some of it fell off, necessitating the removal of the rest) and gained an average of 80kms per tank. I also got pulled over by DOT for an emissions test and they stuck their measuring probe up the exhaust pipe (no cat, unleaded fuel, no emissions gear) and got a "very good to excellent" overall rating!! The inspectors were quite surprised, and impressed! I laughed as I drove away

Pain is temporary, quitting lasts forever.
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Legally converting na6 to 1.8 in Victoria?
If it was going to be inspected then I'd probably go the whole way with NA8 ECU, engine loom, MAF, coilpacks, O2, etc and spend a evening or two planning out re-splicing the engine loom onto the old looms and old looms in the cabin into the new ECU. You and I both have all the wiring and pinout diagrams already.
If it's not to be inspected then there's alway Megasquirt, but still with NA8 sensors, etc..
If it's not to be inspected then there's alway Megasquirt, but still with NA8 sensors, etc..
’95 NA8
- Matty
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Legally converting na6 to 1.8 in Victoria?
mx52nv wrote:Matty,Matty wrote:I inquired on this a while ago. It's more than a 10% capacity increase, so technically you need to get it engineered. This would require all of the emissions equipment from the donor car (ECU, fuel system, AFM, intake and exhaust through to the cat - ideally a while wiring loom swap).
On a practical level, you could very likely dump in a 1.8 with the 1.6 running gear, take it to a VicRoads office and have it signed off as a direct swap because they just wouldn't know...
I read the VicRoads' rule quite differently. Since the NA8 and NA6 are essentially the same model chassis, the largest engine fitted is the 1.8 BP. Of course, I do not know for a fact if this is correct on Victoria but in WA (so different state so different rules), this is legal. All we do is submit a change of engine (number) form.
Hmmm...there must be someone in Victoria who has done a BP conversion to their NA6 already and can confirm legality and administrative procedure? Unless Matty is talking from actual experience, in which case I will again return to my cave (it is really getting dark in there).![]()
Les
It's OK to swap in a motor that was available at the same time for your car. But since the 1.8 superceded the 1.6, this doesn't apply. The other issue is that the 1.8 (due to the later date) is covered by a different set of emissions standards, so you have to fully comply with those standards. That is my understanding having chatted to an engineer.
That was as far as I took it, I ended up prepping a 1.6 to install.
I am pretty sure though that (at a practical level) you could get away with just an inspection at a VicRoads office to prove the new engine number was what was installed, and they wouldn't know the difference between a B6xxxxxx and a BPxxxxxx. Not that I'm advocating this of course... (by the way, do you want an NB motor?)
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