I can buildz new motor?
 

Got in the majority of my parts finally and began the short block rebuild.

I'm using a motor that Brain has most graciously lent me to rebuild and we will be rebuilding the one in my car for him once this one is swapped in. This motor was built for the purpose of making a shit ton of power, but on a budget. It has the following parts:

- New OEM 323 GTX Turbo (B6T) pistons from Corksport 240
- Boundary Engineering billet OP gears 190
- Ebay gasket kit 35
- King bearings 35
- Ebay WP/Tblet kit 60
- Mtuned rods with ARP2k bolts 300
- Sealed Power premium rings 70

All said and done, add in some for crap from autozone, I spent about $1k. Now I have the ability and experience to put this thing together myself. So there is no guarantee you can repeat my build for the same cost. I did this rebuild on a seasoned, high mileage block because I knew it would likely be loose enough to not need any machine work.

The B6T pistons have a CR of 7.8:1 which will give me the ability to run over 20psi on pump gas. I chose the Sealed Power premium rings based on researching better aftermarket rings and availability. The stock rings are cast and have trouble handling increased power and heat. The top ring in this premium set is chrome coated steel. So it will be able to handle everything I throw at it.

I honed the bores with a flex hone that I have used now on multiple import builds. Low speed with constant up and down motion is the ticket every time. I honed it a little extra because I wanted a little extra clearance for this build. Luckily this made it so I didn't even need to gap the rings. They clearanced perfectly. So I just shaved the corners and put them on the pistons. The rods were perfectly clearanced to the stock wrist pins so no machining was needed there. The std sized bearings I used gave me roughly 0.0015" clearance on the main and rods. Exactly where I wanted them for a street/track motor. The deck was resurfaced by gently scraping off the old HG with a razor. Typically I would follow that up with a 3m scotch pad on a angle grinder at low speed. I was able to remove all the gasket this time though, so that was not needed. The decked ended up flat, yay! So I was able to get by without needing a single ounce of machine work.

I'm still debating taking apart one of my heads and porting, but I'm feeling exceptionally lazy, and will probably put it off until the spring time. I have to swap this motor, rebuild brain's, and then swap his. All before the Nov 17th dyno day. Needless to say, porting is on the bottom of my list.

Turbo-wise I currently have my T3 60trim which I have been running at 13psi. It has a bunch of room left, up to 20-22psi until it runs out of steam. So I am going to see what it gets me since I'm hitting full boost around 3400rpm with it in 3rd. I also have a larger compressor wheel from a 86 Buick GN Turbo that has similar dimensions to a 48trim GT2871R. I might swap that on later if I'm not satisfied with what I get from maxing the T3 60trim.

I didn't take a ton of pics of the motor. I always work too fast and don't remember to stop for pics. Enjoy the 5 I did take.

Brian

Looking good man, I envy your skills.
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That's awesome. I never thought of using the GTX pistons... I'm going to start collecting pieces for a build soon.

Many would say, "Why not put in forged pistons while you have it apart". It is my strong opinion that the stock pistons are not a weak point of our motors. As long as you dont have a shitty tune and aren't detonating I see no reason why they can not hold well over 300whp. Additionally it allowed me to not have to spend a dime on machining costs. That is easily a savings of over $300+ alone. Added to the savings of the forged piston cost themselves, and you are looking at a hefty chunk of savings for a motor that can handle a shit load of power. For $1k its hard to beat what this motor has in it and what it will produce.

If I do end up cracking a ring land, its not like I don't have the ability to rebuild again in short order.

Wow! This looks like a good route.

ah the recent memories. Hopefully your shit doesnt leak oil like mine does.

My shit never leaks....

the pistons look awsome but i wouldnt have gone to crazy with that assembly lube on the bearings, theres a chance that all that thick lube might clog up the bearing oil passages thus starving your bearings. It happens and thats the reason why most builders use just plain regular oil for just the bearings.

goodluck with the build though and i really wish i would have thought about going with the gtx turbo pistons when i was doing my build

That is red line assembly lube. Its not going to clog up any passages. I'm not sure who most builder are, but I wouldn't use anything else on a first start.

what do you use for RTV to seal everything up?

Permatex Ultra Grey is the ticket.

Not to thread jack, but after reading some threads on here and researching our pistons in general, this was the same conclusion that I came to as well. So I ended up getting a set of OEM pistons tri-coated and am running those. I'm not shooting for any particular power number, just want a reliable and powerful daily driver out of it with a chance of throwing some track time at it. Haven't made it to the dyno yet as there are a few small projects that need to occur first though.

In any case, looks like you have a really nice build going on. Good luck with it!

+1, I envy your skills A LOT lol.


I had no idea B6T pistons are 7.8:1 lol.

Do you have a link to those pistons on Corksports website? I can't seem to find them.

You inspire me. I wish you had inspired me 1.5yrs ago when I built my motor.

Brian, did you get married?
I mean, the only reason I can think of why you're not assembling in your kitchen again is because your new wife won't let you. ;)

I'm going to get rockin on my motor build soon. Going 10:1 .040" over with an 01 block and a worked 99 head. Going to go a little bigger on turbo and shoot for low/mid 300s.

Cool to see another member in the low compression crew.

I emailed them directly, they happened to have a brand new set sitting on their workbench. I got them in exactly 4 days on Sat morning from WA to VA. I disassembled/reassembled Sunday. I don't waste much time when I get new toys. Plus I already had all the other parts on my own desk.

That was back in college when I had roommates that didn't give a shit, and a land lord that never came to check up for 2 years. I dropped out of VT because I hated 80hrs of coding and electrical circuits to build things that didn't do a fucking thing. Only to struggle to get c-'s because a few douches that couldn't quite cut it enough to get into MIT killed the curve for the rest of us.

So I'm back living at home for the time being (helping my mom pay the bills, she is having a tough time after not having her teaching contract renewed). I've been out of VT now for 2 years in Dec. Got a job right out of school on contract with verizon doing IT work. Did that for 1.5 yrs until i got tired of management. Now I'm working for a defense contractor as a lan admin. I am still taking classes online full time to get my bachelors in network engineering. Degrees in the IT field are basically a joke. Its all about experience, and while I might be 23 today (shameless bday plug), I have been doing IT work professionally since I was 15. So I have 8 years of experience. Hence, my early success.

So I can fund all my miata shit again.... I wanna get all this shit together so I can finally get on the track next year, wreck, and kill myself. Well....maybe not the last 2 parts. All thats left is a HT, a tubular front sway, and better wheels/tires. I have the rest already installed on the car from a competitive setup standpoint. Now its just needing to get mucho seat time.

End life story.

Nice to see you back and active as well Ben.

I'm an OG in that crew. Respect!

so where does one find a set of pistons like that?

Email Corksport. Likely they can get you a set from japan through their connections. The B6T was a much more common engine overseas.

Thanks bro.

Happy birthday sir.

Happy bday! I work in IT too. SAN/Storage for 9 years etc. Maybe I'll meet you at the dyno day if I can put my car back together by then..

Are these pistons cheaper than forged weseco pistons?

Answer

Great build. I'm taking notes:)

Neo... that looks like an excellent build....

Wish I had skills like that....

I think you'll find a lot of geeks in the "real world" around here... (yeah, one more here)

Dave,

Nice build. I am doing a similar cheap rebuild except for keeping the stock pistons and I am still debating the oil pump.

I was impressed at how little wear my 146K engine had on it. I didn't really have to do any machine work but I went ahead and had them hot tank everything and hone the block. I just have to find the time to port the head and get it back to the shop so they can do the valve job and get it back together.

What rpms are you looking at sustaining with this motor? Im looking at most raising the factory rev limiter by 500 rpm or so I am reluctant to get a upgraded oil pump.

How did the ebay gasket kit look? Which seller did you buy from? From all the pics it seems like most of the stuff is as good as any other gasket set for a hell of alot more. I wish I could justify the FM gasket kit but seriously why does it have to be that much more expensive just cause it has Mazda on most of the parts? As long as you have a good headgasket and shaft seals it should all work just fine, Right? I figure I will be refreshing my head every 30k or so when doing a timing belt in any case.

Did you look at balancing the rods/pistons any? All my factory stuff was real close, I only had one piston that was 5 grams heavier than the other three which weighed exactly the same.

I'm going to be keeping RPMs stock, but I plan on pushing close to 300whp. I didn't want the OP to even be a worry in my head so I picked up the gears from travis.

The gasket kit is great. For many motor builds now I have gotten my water pump, timing belt, bearing set, and gasket set from "domesticgaskets" on ebay. They have fast shipping, and amazing prices. I personally will also be using a Cometic HG that I forgot to add in the original post. I picked it up brand new on ebay for $50.

I did not have any machine work done, including balancing. This build was planned, and executed to be under $1k in total cost.

Funny story, I ordered sealed power premium rings for my recent rebuild, and the oil control ringset was completely wrong. Like, Absolutely wrong. Kind of put a cloud over my day.

Explain completely wrong, cuz mine fit perfectly...

yes please elaborate, I have a package of them sitting next to me.

http://boostedmiata.com/engine_work/rebuild_kit.jpg

I can buildz you new motor too?

please do, master obi won.

Cool build. I like it.

And out your exhaust!

Been a while....Just got the motor in today with the help of Scott, Lars, and Scott(ScottFW). Got the motor pulled in less than and hour, unfortunately swapping the rest of the stuff took longer than I thought it would (I should have expected it...). Anyways, got the wheel from the 89 Buick GN Turbo and 6spd on also. Its got wheel dimensions and compressor map almost identical to a 48trim 2871r wheel. Here is some eye candy, no ebc hooked up, 6th gear.

I plan on using those Mtuned rods, they seem like a really good deal.

That they are, best deal on the market really for what you get.

What was the purpose of this post, other than to waste bandwidth?

Don't hate in my thread!

Uhg! I hate you people. Every time I see a thread like this I get so pissed off that I took such a shitty route on my rebuild and kept stock pistons and rods. The cost wasn't really the issue, I was just stupid and at the time people were still doing OK on stock bottom ends at 250whp and less. I envy your build. Cheap and it should be awesome at your goal.

here's some shots of Neo's swap:

http://www.boostedmiata.com/projects...p/DSC_0001.JPG

http://www.boostedmiata.com/projects...p/DSC_0002.JPG

http://www.boostedmiata.com/projects...p/DSC_0003.JPG

http://www.boostedmiata.com/projects...p/DSC_0004.JPG

http://www.boostedmiata.com/projects...p/DSC_0005.JPG

http://www.boostedmiata.com/projects...p/DSC_0006.JPG

http://www.boostedmiata.com/projects...p/DSC_0007.JPG

http://www.boostedmiata.com/projects...p/DSC_0008.JPG

http://www.boostedmiata.com/projects...p/DSC_0009.JPG

DISH!

http://www.boostedmiata.com/projects...p/DSC_0011.JPG

http://www.boostedmiata.com/projects...p/DSC_0012.JPG

http://www.boostedmiata.com/projects...p/DSC_0013.JPG


That's a 60mm Super 60 T3 wheel on the left, his new wheel on the left. Pretty much going from a T3 based 3060 to a 3071.

http://www.boostedmiata.com/projects...p/DSC_0014.JPG

http://www.boostedmiata.com/projects...p/DSC_0015.JPG

Good thread! I think I am going to go a similar route when I do my rebuild.

Goddamn, Neo. I was going to bump this thread a few days ago looking for updates, so this is like a present. Are you planning on posting on the spool data thread, 5th gear pull with this new motor? I am going to do a 4th gear (5 speed box) pull this week and post it, and am looking forward to comparing. Judging by the data from my 3rd gear dyno pull vs your 6th gear pull, however, here are my observations: I am reaching target boost (178 kpa in this case) at ~4k +/-, you are reaching 177 kpa at ~3650, and creeping higher over the run. And you are obviously pushing more air than I am at a given boost pressure. I am running a GT2560R, and need some help in tuning in the boost building cells, but it looks like your experiment was successful relative to my setup, which is supposed to be a quicker spool setup. I am very anxious for your dyno plot and the associated datalog, I assume you are going to share? Not till Nov, though, right? I'm really curious to see if your torque suffers below, say 3000 rpm. I'll let the experts analyze the data, but it looks promising.

T3s and shorty tubular manifolds pwn j0.

Shit, I have much work to do before my manhood goes from

<

to

>-

I can do that, will do that. I was to busy watching he OP and WT gauges on the way home to really think about boost pulls. I'll try to get something today.

Correct, you will have to wait until the NE Dyno Day. If you aren't a poser, you'll be there in person ;) At that time I hope to be running something like 18-22psi with EBC working.

Also, in for what duty cycle those 550s are at on the big end, mkay? Maybe add to the bottom graph in mlv? plz thx. How does it feel on the low end, anyway? Fuckin sweet budg build, man. I have respect.

This is funny. Those pistons where mine, lol. Derrick at CS ordered me a set for my new engine and after talking to him and the builder, then decided to go forged. Sounds like he hadnt shipped em back yet or decided to keep them for stock. Enjoy'em! :giggle: