wiahwibby

I am considering putting a 2001 motor in my 97. I have come across a good deal on one and am trying to figure out if it will be feasible without having to hunt down a ton of little connector/sensors/random parts to get it to work.

Quick details:

I have MSPNP, no MAF. LC-1 wideband.
I don't care too much about having VVT for now (aided by the fact that I can't afford the extra controller right now).


I need to know of anything that I'll need to do/acquire in order to get this motor operating. I have read a decent bit about the NA CAS vs. the NB trigger wheel. I am familiar with setting the timing on an NA, but I've never really messed with the NB motors much. I'm not sure on the details of the situation of the timing sensor feeding off of the VVT controller on the 01 motor. If this is the case, does that mean that I have to have the VVT working in order to get an ignition timing signal?

Also, lastly, is it known what (if any) parts, plugs, harnesses are needed in order to perform this swap? Do I need the wiring harness from the 01 motor?

edit: Also, is it known if the engine mount locations are the same for an 01-05 NB motor as they are for an NA 1.8?

Joe Perez

iTrader: (8)

Since you have an MSPnP, you need to bring over the CAS from your old motor.

The MSPnP was designed with the older MS1 CPU at its core, and because of the limitations of the software that runs on that processor, the NB's rather unusual crank and cam patterns cannot be properly decoded. So unless you want to upgrade your ECU at the same time, you're probably best off leaving the wiring harness under the hood completely alone, and transplanting the following items from your old '97 motor onto the new motor:

1: Ignition coils
2: TPS/IAC
3: CAS
4: CLT sensors (both of them)
5: MAF sensor (only if you are still using the IAT sensor which is built into it. Otherwise, none needed.)
6: Alternator
7: Anything else which has an electrical plug.

You're probably also going to want to transplant the fuel rail and its associated FPR from the old engine to the new. In '99, Mazda switched to a returnless fuel system (meaning the FPR is at the back and only one fuel line goes to the front) whereas your car has a second fuel line and is expecting the FPR to be up front.



Yes, the engine mounts are the same.

FatKao

I put a 2001 motor in my 1997 shell a few months ago.

To do it and not have it be a hacked up mess you need:

*Coils and plugs from a 2001+ motor VVT piping blocks the mounting location for the 2000 and older coilpacks.
*2001 harness for the plugs for the coilpacks/VVT/CAM sensor. Ebay often has these for reasonable prices.
*CAS, oil pressure, water temp, accessories, exhaust from the 1997 motor. When in doubt use the 1997 part if it fits.
*Crank sensor with a CAS system is just for misfire detection, which you don't have without the OEM ECU, feel free to dump it. NB crank sensor will be needed if you want to use the VVT eventually.
*2001+ cam sensor or blockoff plate, there is a hole in the valve cover otherwise. Need the cam sensor if you want to use the VVT eventually.
*2001 intake.
*TB doesn't matter.
*Fuel rail from a 1999 motor. You need the one that has the FPR/Damper opening pointing towards the front of the car, not the one that has it pointing towards the wheel wells. Once you replace the damper with the 1997 FPR just run some FI fuel hose to the existing fuel system matching how it was hooked up on the 1997 rail.
*Motor mounts from the 1997, this is a direct bolt in physically.
*If you're keeping EGR, you need the EGR equipment from the 2001 motor, not sure if it's a bolt in or not but the 1997 stuff won't work. Mine isn't a street car so I blocked it off instead of dicking with it. Keep in mind there is no power gain here deleting it. EGR isn't a bad thing but it wasn't worth spending money on for a track toy to me.
*1997 cooling system is a direct bolt on.
*1997 Starter

wiahwibby

Ok, first off, thanks a ton for the clarity. I know I should know the answer to this but, what is/are the CLT sensors?

To add, I am using a FM dual feed rail. I noticed that they sell a different model for NBs. I never knew about the returnless change they made. Will I have any trouble bolting/mounting it? Should I use the 97 fuel injectors or the ones that come with the 01 motor?

This may be a good time to switch over to COPs also....

Alex

wiahwibby

Thanks fatkao. You being in Durham, it may be nice to get a firsthand look at your car to get an idea on what to expect. Any chance you could meet up with me one evening?

richyvrlimited

iTrader: (1)

You can use the 2001 fuel rail quite easilly, just just have to remote mount the FPR, I did it by soldering a 90deg barb to the fuel rail then soldering a barb to a spare FPR flange (cut off an old rail).

CLT sensors are engine coolant temperaure sensors.

You need to keep the 97 engine temp sensor OR reprogram your MSPNP to use the 2001 sensor, the former is easier however as the connectors are different.

You also need the dash temp sender, it's close to the ECU sender, but a tiny 1 wire sensor, the 2001 dash is fed from the ECU, the MK1's have their own sensor for the dash. The 2001 engine will have a grub screw blocking the hole for it.

EDIT, also if you have an early Oil Pressure sender i.e. the large grey thing rather than the 'idiot' light, you'll need to slightly modify the starter motor support bracket for it to fit.

FatKao

Sure. I broke the heater core taking the 13 year old hoses off (Oh yeah watch for that too, they get really stuck on there and if you pull too much it'll crack the pipes) so I don't have heat in the car. I'd prefer to wait till it's a bit warmer than 20* in the morning/evening before I take the car on a drive. I work near SAS so I'm not too far from Raleigh most days.

I can't comment on the FM rail. I don't believe the bolt holes are the same spacing though NA head vs NB head. The NB rail might have issues mounting the FPR you'd need for your NA system. Hopefully someone who has used the FM rail on a NB head with a return type fuel system can comment.

Joe Perez

iTrader: (8)

From FM's website:

M-Tuned's website clearly states that they, at least, use the same rail for both NA and NB applications and that only the fittings differ. Specifically:While this doesn't help you with the FM rail per-se, it does suggest that the spacing is the same and that the rail itself should fit your NB head. It would then be a matter of rigging a remote FPR setup as richyvrlimited suggests. I suspect that if you came into possession of a fitting such as the brass one depicted in this image, you might be able to make it all come together without having to solder anything.




There's been a lot of debate about this in the past, and I'm not sure that anybody has ever posted solid, empirical data to support one conclusion vs. the other.

Mechanically and electrically, the NA and NB injectors are compatible and interchangeable. The tenet of the argument has to do with the fact that the pintle / nozzle design is slightly different between the two. One school of thought argues that the '99 and later injectors produce better atomization of the fuel. The counter-argument holds that this property is contingent upon the fact that the NB fuel systems run at a somewhat higher pressure (55-60 PSI above atmospheric) than the NA (40-45 PSI above manifold pressure) and that when operated at the lower fuel pressure provided by the NA's fuel system, the NB injectors will under-perform the older NA injectors.




Danger to the man who changes too many things at once.

At the very least, get the engine up and running with the old ignition coil just sitting on top of the head. Once you know that works, then go for the COPs.

There's nothing worse than staring at a non-working engine and wondering which one (or three) of a dozen different things that you just changed is at fault.

wiahwibby

Thanks for the help guys. This info is making me want to get this motor asap. needs monies...

And yea Joe, I was thinking that very same thing as I typed that statement. I think solving the fuel rail issue should be fairly straightforward, just have to spend a little time with it. As for the fuel pressure vs. fuel injector issue, I wonder if that would be best solved with a secondary adjustable FPR?

Once I finally get the motor and get things going, I'll probably be coming back with a ton more questions. I have to finish one other project first though. Hopefully that won't take too long.

jacob300zx

I would assume that the FPR determines which injectors are used?

Joe Perez

iTrader: (8)

It's rather open to debate.

The NB fuel pressure regulator isn't a direct drop-in for an NA chassis. If you really wanted to replicate the NB fuel system, you'd need to bring the whole thing over.

And frankly, this would be a bad idea. A lot of NB owners have complained that, by comparison to the NA, the NB's fuel system becomes inadequate much sooner at high-HP conditions. Because the FPR is in the back, it cannot respond to changes in fuel pressure at the rail caused by pressure drop across the lines at high flowrates.

For now, assuming the engine is not turbocharged, I'd suggest that wiahwibby retain the NA injectors. Fewer uncertainties this way. Since this is MiataTurbo.net, I assume that a point will soon be reached where any stock injectors are inadequate, and then it'll be a non-issue.