Damo's 1992 Mazda Astina BG Turbo

[SLY 323]

Hi all!

A few days ago I was searching around on carsales like I do pretty often for anything interesting, and I did!

I came across this BG hatch with a GTX motor transplant.
Decided to go take a look at it, and then it came home with me.

Now, from what I can see and receipts, the motor and gearbox was rebuilt before putting it in, with a custom 3 inch exhaust, and new intake piping along with a front mount intercooler and a turbosmart BOV.
Runs on a standard GTX ECU with Unichip piggyback and a Turbosmart dual stage boost controller, set to 8psi low, and 12psi high.

The brakes are slotted rotors all round with bendix ultimate pads. Lowered 2 inches on pedders springs with Koni adjustable shocks and 16 inch Bob Jane rims.

Havent had much more time where it isnt dark or not raining to check the car out as a whole and see what else is there.

Well here are the pics!
















So, there we go. Any suggestions as to what I should be upgrading first (apart from ECU) let me know as I dont even know where to begin!
Cheers!

[marcs_sp20]

Geeze, you and cookie playing Pokemon to "catch them all"

Looks good mate

[HAIGHIE]

donate it to haighies collecton fund lol nar looked really tidy last night man

[derb]

Remove that horrible rear sticker.
Get some a-pillar covers.
Install coilovers.
Upgrade brake pads.
Go thrash it.

[TheMAN]

looks to me the VAF has been opened and adjusted... maybe this is a RX7 VAF?

sounds like you got a good deal on the car... I don't really like the gear lever and wheels though

[Clean_Cookie]

Replace bov, gearknob, steering wheel to get it less defectable, then paint the cooler black so its leas noticeable, add a lip like anthonys, and new a pillar moulds. Then it'll be another killer bg.

[SLY 323]

Derb - Sticker is horrible and has been replaced with Mazdaspeed badge. Do you mean the missing plastic on the outside of the car? I think Coilovers would be too much. I like the ride of the Konis. Yeah the brake pads are horrible, thats on the list. Also the pedal travel is extensive, so not too sure there, maybe fluid?

TheMAN - Yeah the VAF has been modified in some way. It has silicon around the top. What would be a way of identifying if it is RX7?

Cookie - I want to relocate BOV hidden or go another choice? Yeah I wanna remove the gear knob its horrible, does anyone know where I could find a short shifter kit? The steering wheel is listed on the engineers certificate, along with the boost gauge and intercoolerand exhaust. What does the lipmlook like? Im already hunting a rear wing and replace the exhaust tip.

I was alsomafter some options for more power, also the possible benefits of a EBC?

[Clean_Cookie]

More power? These things fly on 14 psi, maybe the piggyback (which is really not needed) is causing it to run rich or something. Maybe the rules are different, but those sort of steering wheels aren't allowed on any car newer than like 1980. Must be padded in the center. Anyway, at least its on the engineers cert. Ive got a fair few stock ba knobs ones if you'd want one, just the cost of postage.

[SLY 323]

Maybe its not a GTX ECU? I just figured the piggyback was for removal of the boost cut and a remap. Dont get me wrong the cars quick, very quick, but just not right compared to another BG Ive been in. :S I think it needs to be put on the dyno and have everything checked.

[Clean_Cookie]

Afaik, a piggyback needs to be tuned on a dyno, possible this was never done and I think it'dbbe worth going and getting it checked out. Maybe remove the fuse and replace with the stock afm and see how it feels (if it still works due to the install of piggyback)

I've got an ecu you could test, if no one has one closer. (Jap spec)

[SLY 323]

Hmm. What power does a standard GTX make atwkw?

[derb]

Pretty sure the RX-7 VAF has a B code sticker on. Also be careful running on 14psi, the factory boost cut it at 1 bar [14.4psi]. I run mine on 13psi to be safe. A good quality EBC will keep it exactly where you want it though.

Check the ECU for 'BP26' on it, that's the jap-spec GTX ECU.

I hate noisy BOVs plus they are a roadworthy/defect item. You see that big nut in you turbo intake pipe after the VAF? That's where the factory plumb-back BOV goes into. You might be able to adapt the current BOV to be plumb-back.

Stock GTX engine should make about 100kw atw, wound up to 13psi it should make 130kw atw or more. TheMAN will correct me on those numbers I'm sure.

And I actually have a short shifter brand new in box at home. Bought it to replace my current one but reliased it was linkage bushes, no the shifter at all.

[SLY 323]

Ill check the VAF for that code. Is there an EBC you can recommend. At the moment Ive just got a box with 2 adjusents and the gauge reads (Im only assuming here as its not exactly accurate.) 12psi at max. When I was driving it back from buying it, everytime I put my foot down it jerked and hesitated and cut out (boost cut?) after turning the nobs down (3 on high and 6 on low) and refuelling with BP ultimate it never did it again...

Whats some bolt on mods to stretch it out to say 150atwkw?

Would you be willing to part with the short shifter? As the one in there at the moment has a huge throw and is super sloppy.

[Mad Mat]

U know the reason y there is silicone on the vac.. If he is running a gtx ecu (which u should really check, altho u can run a bg ecu with gtx gear with a piggyback.) and got a piggy back. Some tuners actually remove the cover on the vac and adjust the gears in there so that boost cut doesnt kick in till 17-18 psi.. The mx6 boys do it all the time.. Also mate pm me as i have a wicked idea for ur first upgrade and it will cost less that $50 and increase responce by 50% hee hee

[Mad Mat]

Ow but man nice car id get coilovers and suspention sorted before getting a lsd from mfactory

[TheMAN]

any shifter for the BG, BA, BJ will fit.. even the shifter from the MX-3 fits
in other words, you can buy a short throw shifter for the BJ and it will go right into the BG

try to find yourself a shifter boot from the GT-R... it is leather and it looks much better... fits perfectly and replaces the accordion boot! The GT-R gear knob is also leather too

[derb]

With a 3" exhaust I wouldn't be surprised at all if the boost was spiking above boost cut, and you really should run 98ron fuel if its the jap-spec ECU. As for a good EBC I would definitely recommend the Gizzmo unit. A bit cheaper than the JDM name brands, but worked amzingly on my mate's TX3. There won't be much cheap bolt ons as you've already got an exhaust and intercooler. And there is no point getting bigger injectors for the stock turbo. To be honest, the only real bolt on left is a vf10 hybrid turbo. Then you can get bigger injectors and tune it up. And yes I don't need that shifter at all. $50 including post sound OK to you?

TheMan, redlinegoods make leather boots for both shifter and handbrake. I have them both, they look great, and you'll pay less than $100 for both with shipping included.

[Mad Mat]

U could bolt on a evo turbo from a evo 6-8 they have epic responce but u need aanifold of one of them... But i do here that i can just get a evo tubular exhaust manifold and cut the glange off it and use a bp exhaust flange and weld it onto the exhaust manifold and it will line up

[SLY 323]

Matt - Well the guy I bought it off said it had been run on 17psi when he got it, though lowered that because he kept screwing cv shafts?
Ill PM you now
The Koni adjustables are great as it stands it feels really solid to drive and Ill probably keep it that way other than maybe a sway bar and a brace or two. How much and where for the LSD if you know?

Derb - The guy mentioned also about it having an "IHI Turbo" but after some research thats just a collective or brand name for it? How would I identify the turbo? Also from what I can gather the turbo doesnt kick in till anywhere around the 5k mark, as inbetween gears its off boost for a second then back on.
Why would a big exhaust cause a boost spike?

[derb]

LSD comes from mFactory in California and is about $700 pre-shipping. Damn cheap for a gear-type LSD, no clutch packs to wear out.

You'll need to try and read the little info plate on the turbo as you have guessed correctly that IHI is just a brand. Hopefully you already a VF10 core/compressor or something bigger by the sound of it. 17psi is much more than a standard GTX turbo could ever push.

Exhaust can cause spike by letting the exhaust gasses flow too freely at high rpms. Without enough back pressure from the exhaust the turbo can spin more/faster than you want it to. For example, in my mate's TX3 before he fitted the Gizzmo EBC it would sit on 12psi until about 5500rpm when it would bleed up above 14.4psi and cause the boost cut to trigger. I have a relatively tiny system, 2.5" dump and cat, then 2.25" all the way back. My boost goes to 13psi and stays there until I redline.