Miata BP Build

[Midnitehours]

This is a continuation of this post

The current BP motor in my Miata is questionable at best.

It's a high KM motor,
pulled out of a wrecked miata,
sat in the corner of a garage for 3+ years.
then forced back into service by me to the tune of 14PSI.

and the BIGGEST problem: the speed3 sees 21PSI.

We're gonna remedy that:

build specs:
original 195,000 KM BP 1.8L
Manley Forged 4340 H-Beam rods.
NPR standard sized piston and rings 83.00MM (oem spec stuff)
ACL race main bearings set,
ACL race rod bearings set,
ACL race thrust bearings set,
Supertech intake and exhaust valve seal sets
Spec stage 3+ clutch
Fidanza 18Lb flywheel
BEGI tubular manifold
T28 journal bearing turbo
BEGI divorced downpipe
ARP hardware here and there
Snow own bastardized stage 2 meth injection.

this is how it got put away at the end of the summer:


Oil return line broke sending oil all over the down pipe.

cheap ass ebay mainfold self ported and said FU to gaskets

[Midnitehours]

Old BP Out. The rear main seal and front main seals were shot due to incorrect vac line pluming and thus pressurizing the crankcase to 12 PSI. oops.



VC off, and to my surprise, the engine had been rebuilt before.

Cam caps stamped 1-10




Head came off, to find proof that it ran very very very rich. also small evidence that there was detonation or, engine ate something. The cylinder walls were still in really good shape






oil pan off


discovered crank had been balanced. Initial $800 investment seems very good at this point.






all apart:

[Midnitehours]

Head was completely disassembled, and to my surprise, the valve seats were either replaced or, there was valve work done, as the valve seats had perfectly smooth machined transitions into the bowls.

either way, a valve clean up, and lapping were in order:

I soaked the valves in seafoam with little result, so the brass wire wheel and drills were comissioned.

Valves and seats then got lapped.






Exhaust and intake ports got some attention.
exh before:


exh after:



intake before



intake after

the cast was really shit, with ridiculously sharp angles coming off the opening. Dremel with carbide bit took care of it.


less homo bits:






[IMG]http://i92.photobucket.com/albums/l40/midnitehour/IMG_3258_zps74c965b2.jpg
[/IMG]


complete with arp 2000 hardware


rings and pistons




If you noticed these pistons are different than the ones that were in my previous motor,

The 94 block has a 8.8:1 compression ratio.
These have a 9.0 : 1 compression ratio.

Most argue that a lower compression ratio is better for big boost, as you increase the combustion pressures via boost levels rather than a mechanical process. This helps reduce the chance of detonation.

The bigger turbo is bit slow compared to the T2554 I had in there before, with full boost coming on around 3300 rpm, rather than the 2000 rpm.
increased compression ratio should liven up the "out of boost" preformance.
and to fight detonation up top; I will be running Meth from 10PSI and up, Detonation will not be an issue.

[Midnitehours]

balanced the reciprocating assembly:
I had to buy a scale that was more accurate than the one we have.

AWS-2000, 2000g capacity, 0.1g accuracy. in reference a US dollar bill weighs 1 gram.



started off by weighing the snap rings for the piston / pins, the pistons, and then the wrist pins individually









The bearings were weighed all together, and then matched to the average.





the individual pieces are then matched to get the smallest difference between the sets.

then a pair of sets are matched to get the smallest difference


bagged and labeled




By doing these steps:


The difference in the pin end between the lighest and heaviest set is 0.2g
The difference between the pairs of assembly is 0.5g or half a dollar bill.

OEM tolerance is 1g difference between each cyclinder assembly.

she's gonna be one smooth motor.

Up next this month when i'm not at work,

setting ring gap, head assembly, and hopefully, fully assmbled.

[CorkSport]

The stamped cam cams look stock to me as well as the forged crankshaft and the balance work.

We ran a boosted BP in our 01 Protege drag car years ago and they are a tough motor.

-Derrick

[Midnitehours]

Originally Posted by CorkSport The stamped cam cams look stock to me as well as the forged crankshaft and the balance work. We ran a boosted BP in our 01 Protege drag car years ago and they are a tough motor. -Derrick

The cam caps came stamped from the factory? I didn't see the stampings on my other bp. Also it looks like it was done by hand as one of them had a partial stamp and then was stamped again.

I do love the bp. Possibly my second favorite Mazda motor to the KL. Although i'm sure that would change if i got a rotary.

[socks]

looks to me like it ate something, rather than detonation.

[Lex]

Very nice - I have a soft spot for these cars as I started out in a BP powered Escort GT. If you're looking for a tuning EMS, we have you covered

Plug and Play ECUs : Stratified Automotive Controls

[Midnitehours]

Originally Posted by Lex Very nice - I have a soft spot for these cars as I started out in a BP powered Escort GT. If you're looking for a tuning EMS, we have you covered Plug and Play ECUs : Stratified Automotive Controls

It's got a ms2.

Now if you could guide me through getting knock sense up and running it'd be great.

A friend of mine just picked up a ms2 for a KL mx3 from you.

Hopefully i can get my other buddy to get one from you as well for his klze gen 1 protege

[Lex]

Originally Posted by Midnitehours It's got a ms2. Now if you could guide me through getting knock sense up and running it'd be great. A friend of mine just picked up a ms2 for a KL mx3 from you. Hopefully i can get my other buddy to get one from you as well for his klze gen 1 protege

Yes, I would not mess with anything not plug and play in these cars and the MS3s are not there yet and not sure if they will be.

I can certainly help you with the KS but it is not the best unit out there. I would personally look at something with better filtering and more processing power. This is something I've wanted to build for a long time.

In the meantime have you considered these guys?

Phormula - Engine Knock, Detonation and Pre-Ignition Detection and Monitoring Systems

[Midnitehours]

That is an expensive alternative.

Also down to support any beta testing

Sent from my SGH-I747M using Tapatalk 2

[Midnitehours]

Originally Posted by Lex Yes, I would not mess with anything not plug and play in these cars and the MS3s are not there yet and not sure if they will be. I can certainly help you with the KS but it is not the best unit out there. I would personally look at something with better filtering and more processing power. This is something I've wanted to build for a long time. In the meantime have you considered these guys? Phormula - Engine Knock, Detonation and Pre-Ignition Detection and Monitoring Systems

LEX: Any experience with the J&S safeguard. Do you think it could be used effectively with the MS?

Sent from my SGH-I747M using Tapatalk 2

[Lex]

Originally Posted by Midnitehours LEX: Any experience with the J&S safeguard. Do you think it could be used effectively with the MS? Sent from my SGH-I747M using Tapatalk 2

I've heard about it - does it directly control timing or does it have an output based on knock? A bunch of the MS protege guys were using this.

[Midnitehours]

From the quick read i did, it delays the signal to the coil pack when it senses knock. Essentially pulling timing.

It's very simple and isn't progressive in how much timing it pulls

[Lex]

Originally Posted by Midnitehours From the quick read i did, it delays the signal to the coil pack when it senses knock. Essentially pulling timing. It's very simple and isn't progressive in how much timing it pulls

If it has a good filtering circuit, you're able to also log this, and can find it at a decent price it can be worth it.

Since you are taking control away from your standalone when knock occurs you'd want to at least log when knock occurs.

Really the most important thing here is to be able to tune the knock filtering circuit so you don't get false positives and yet still pick up knock.

[chance91]

What do you plan to run for an Intake manifold?

also, is this a bp4w or an older motor?

God Na's are lucky. Looking at your pic you got all the room ever.

give me a shout, let me know if you got questions. It will give you the power you want I'm betting.
http://img.photobucket.com/albums/v2...ps2d4a7f6d.jpg

[Neverlift]

@chance91; Did you blow the msm and fall off the msf planet for year? Must be getting close to running for you to crawl out of your hole lol. Welcome back.

[chance91]

Originally Posted by Neverlift @chance91; Did you blow the msm and fall off the msf planet for year? Must be getting close to running for you to crawl out of your hole lol. Welcome back.

No, I work too much to live on forums these days. I dunno If i mentioned I'm in the oilfield, work about 100hr weeks. I did pop my MSM motor in 2010, i dropped another one in. Took about 6 mos. Back in december, I decided to get the exhaust redone, I removed the stuff I built, kept the ARtech downpipe, and decided to get an ARtech exhaust manifold as well to ditch the FM stuff.

Because i took such a big bite into it, i decided I may as well dig in with both hands. So, upgrade ECM to 2.7, redo intake and get a new 68mm throttle body, put back the 1000cc injs that now work with 2.7 and didn't with 2.5, etc etc. And yes, it is pretty close to being all done and buttoned up to my satisfaction again.

However, I'm poking around here cause I bought a Mazda 3 and need parts :-D

P.S. I don't wanna thread bomb anymore, and I do wanna say, OP has likely better engine building techniques than me. I do love British Racing Green as well.

[aaronc7]

build this thing yet?