84 12a bridgeport drift car
 

Bought an aborted ITS (i guess?) rx7 project a little over 2 years ago without any serious plans for it. This is the way the car looked when I picked it up

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Ditch the wiper arms at a minimum :O

They got nothing to wipe LOL

and nothing to wipe with.

A few months later a put my datsun project on hold for a while and I got excited about the rx7 and ordered a bunch of parts to build a decent motor and rattle canned the thing black with a rising sun on the hood

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Also found out that I had a set of bridgeported irons (came with the car, I didnt know anything about rotor engines when I got it), so I decided to do the bridgeport bit.

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Ported my housings to go along with the bridgeport
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I also got a good deal on a used seat and harnesses and picked that up

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Stripped the rest of the interior (dry ice - sound deadening and all that) and put the seat in

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The previous owner had pulled off a real hack job of fabricating (i use that term loosely) a way to install a fuel cell.....

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So I replaced that with this version that I made
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Here's a pic of the fuel cell mounting frame welded into the car and painted
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I picked up some ZG fender flares, chopped and seam welded the fenders and put those on next
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Also bought some rota grid v wheels for the car
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And then bought a front lip for the car, mounted the oil cooler out there and put the wheels on
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For those interested, tires are 225/45/15. Wheels are 15x8 0offset front and 15x9 0 offset rear
One pleasant fact I discovered while looking for wheels is that the previous owner did the GSL-SE brake conversion, so I was able to get 4x114 wheels

Found a sweet old school whale tail spoiler on craigslist and put that on
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At this point I'm pretty convinced I would like to try my hand at drifting the car (hence the thread title) so I made a mounting plate around the shifter to attach a Ksport hydraulic hand brake to.
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Then I got around to making a dash for the car since I didn't like the aluminum sheet one it came with. Nothing is wired up yet but it gives you a general idea of the layout. Using autometer tach, oil pressure, oil temp and water temp. Have a 14.7 brand wideband (the blue box) and a EGT on the far drivers side. Also got my dream sparco steering wheel! Switches are longacre brand and the two shift lights are summit adjustables. Thought I would run two shift lights since I'm not super used to hearing engines rev very high (8k+) so I think I will set one up 1k below rev limiter and one 250 below rev limiter so I can have the poor man's sequential setup
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The cage in the picture is a bolt-in autopower setup but unfortunately I think it will have to come out as my head smashes into it while seated. I'll probably just end up running the roll bar until I get the car on the road and have time to weld in a properly fitted cage.

So there's a quick picture summary of the last few years with this car. Currently I'm preparing to build the engine. I sent the engine plates to a shop by my folk's house in wisconsin called TripleR to have them surface ground. The rotating assembly was shipped to Racing Beat for balancing and clearancing but USPS dropped my rotor box and smashed a corner of the rear rotor so I'm dealing with that whole saga right now. Thankfully Jim Tanner is a great guy and has been super helpful with the whole process so I should be getting one of their lightweight rotor assemblies later this month! Still working out the details if I can use my counterweights or not but I should be all set with a balanced assembly and a brand new E shaft (mine was worn out and not useable for a race motor application) by the end of the month! Of course it had to be the rear rotor, as I tore apart 3 engines to get one good rear rotor and have spares for the front... but that's how it goes. I'll post more as I get into the engine build and start plumbing and wiring the car.

nice!!!

I really like your dash. What did you make that out of? How much did it cost, roughly?

Just saw this one, that's a pretty gnarly looking car man! Like stated, dash is spot on and the strip and paint must have been pretty cheap so you have one helluva drift machine right there. You're probably already used to solid rear axle feel with the Datsun so it shouldn't be too big of a jump to this car. Good luck with it! :bigthumb:

That is a sick build. Keep the pics coming

I absolutely love the white inside and black exterior!! Keep the progress going.

Thanks!
Dash is a welded frame of 1/2"x1/2" steel tube with a sheet of black abs plastic from menards attached with rivets. Total cost was probably less than $30
Moved back to Wisconsin a few months ago so progress has been slow but I'm setup in a garage now and should have updates on ignition system and exhaust within the next month or so.

motivation first gen killing it

That dash is awesome!

Thanks for the info! That's exactly the look I would like for my project.

where are you located in WI, do you plan on hitting up USAIR for some dday events next year im in the middle of building a non turbo 13b 86 rx7, mainly suspension and cooling and of course making it look sexy

I'm in Waukesha now. I'm planning on trying to make a drift day event with clubfr or something next summer but I'm not sure it will be done by then. I ran into a problem with my irons, I believe they have had too much material removed during surface grinding. I'm going to research the effects of running plates that are thinner than the factory specs but I think I will run into stackup issues.... So I might be tracking down another set of plates and redo the ports again.

So i'm back in wisconsin, got a workshop together for the car and started working on it again. Here it is in the new shop.
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Also picked up some APR mirrors and used some aluminum from the old front bumper to make mounts with the proper angle.
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Recently I've been soldering the megasquirt together that I plan to use for ignition only. Also making a megaview panel for the dash. I'll figure out some sort of trigger wheel and run individual coils for now and stick with the weber for fuel delivery. Gives me room to grow into EFI if needed.

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looks awesome cant wait to see the thing ripping it up

I want to see more of this thing!

Looks great, I cant wait to see it in the track!!!

This car looks mean in flat black with the flairs!

Where did u pick up those dollies? Are they from harbor freight?

Love the look of this thing! Cannot wait to see this FB killin' it!

Been a while since any update, lots going on.
Bought a house and finally have a nice shop space. The boys helped me rewire everything with 4 outlet boxes and a bunch of 220v, insulate and sheet the walls, put in new light fixtures too so its nice and bright.
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Heres the finished product
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Built an area for shelving and storage too
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Few pictures of the car outside
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In more specific rx7 news, finally have all the pieces for the engine!
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Heres the new bridgeported irons in detail
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Got the intake manifold port matched and found a crank sensor to use for an ignition trigger too. Here's a picture of one of the racing beat lightweight rotors I will be using for the build.
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So thats it for now, going to be a very busy summer but hopefully I'll have the motor together before too long.

Great work,the car is sick...

This car is sick! Keep at it :3

man I'm loving this build I really like your hood man lol I want it the design of the rising sun is amazing =w=

Nice

Finally back at working on this car again, it's been way too long!
Found some time to work on the engine over the holidays, took me way longer than expected just to get everything clean and laid out for assembly.
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Built a little fixture for grinding the side seals using a dremel tool spinning an abrasive stone in the corner seal spot and cut the tip off a junk rotor so i can slide a side seal up against the stone at the correct angle for grinding.
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Result of the tedious job of side seal clearancing...
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Finally on to final assembly. First engine I've ever built but I was happy with the way everything turned out, seemed to hit all tolerances without much of an struggle or ruining seals. Rotor side seals and corner seals all moved freely up and down without binding. Did have to take some time on combination stone with the spacer to get the front stack up endplay in spec since I was only showing 0.010" endplay at first.

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And here it is all together
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Ignore the crank angle sensor, just a placeholder till I figure out how to time this gilmer pulley assembly and drop a distributor in. All seems well with the engine, spins freely and I can hear compression as the seals go by. I finished mounting up the clutch and pressure plate but when I tried to install into the car I can get the engine and transmission to mount up OK but when I try and lower the engine to meet the front engine mount I'm hitting the steering link with the oil pan. Seems like the whole engine needs to move about 1 inch forward to clear the steering link but I'm not sure how that's going to be possible. There is room to put the pan sump between the back of the subframe and the steering link but the alignment seems off front to back and the pan hangs up on the link by at least the back inch of the sump. Maybe I'm missing something obvious during the install or maybe I've got a goofy pan on it? Not sure, had so many engines apart in the garage to get parts for this one I may have mixed and matched pans but its a 12a going into a car that had a 12a in it originally, not sure what I'm missing. Here's a picture of the oil pan I'm using if anyone has a clue for me?
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So that's it for now. Hopefully I'll solve the clearance issue and be back at it shortly.

What you going to do about the suspension? I drift an 83 and I'm having trouble with steering angle and the horrible steering setup.

That looks like an RX-3 pan. You need an RX-7 pan.

Not sure yet. I've never driven the car so I'll wait and see how it does with the stock parts and then modify as needed. What are you planning on doing or what have you learned with yours?

Thank you! I figured someone would know what was up. Here's another picture just to confirm but from what I've seen on Mazdatrix website the 12a rx7 pan is certainly different than what I have.
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Unfortunately no one seems to have them in stock new so I'll have to try and track down a used one. Thanks again for the help

I've learned quite a bit. First thing is to completely remove the steering stops on the control arm. Also I'm running 15x8 rims with 0 offset. I have no clearance issues. I just came from a NASA practice drift event and was happy with this but I can see where I'm in need. I have a few ideas that I can't share yet because I want to make sure it will work but it will definitely give me more angle. One other thing I would definitely recommend is to get adjustable control arms. Camber is a really big thing in drifting. It's actually a functional thing not just cause Honda guys think it looks cool. Also castor/camber plates. I've been talking to techno toy tuning and he actually made steering arms but you must run a 17" rim for them to work. Trying to get my hands on his set just to try them out. Will keep you posted on my findings as well as any more ideas or recommendations. If you find anything let me know. Btw, I'm trying to build my other car so it can compete in Vegas drift and formula drift. Which makes it really hard so that's why I have to think out of the box on the suspension setup.

Post a want to buy on the forum. Anyone who tears down lots of 12As will have several pans.

Nice car man!
but what are these marks on the bridged iron?

Awesome thread so far, can't wait for more! Thank you for sharing and happy sliding!

Excited for videos!

This is some awesome information I have been asking/looking for about wheel sizing on the RX7... Thank you!

I am going up to 17x8 pretty soon. The 15 just has too much side wall which allows for too much flex. It will work for now but think about going lower profile.

Got one really quickly. Thanks

Media blasted and painted the proper rx7 oil pan and the engine went right into the car over the weekend. Decided to use solid aluminum engine mounts and was suprised to see how much taller they were than my stock rubber worn out mounts. Might turn them down a bit to compensate for the difference. Also thought it was strange how the engine is offset towards the drivers side. Drew a string down centerline and the front of the engine is offset and approaches center as you go backwards towards the trans. Figure there is no other way to install it so I'll let the Ujoints handle that?

Still have to block off the intake manifold coolant passages in the housing since the racing beat weber manifold doesnt use them. I'm reading that the preferred method is dorman part #555-101 20mm freeze plug so I'm going to order some of those and try that out before I resort to JB welding a quarter in there. Couldn't resist mocking up the carb setup anyways... Exciting times! haha

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More progress and should have another update soon.

The engine offset is normal.

Your aluminum mounts look way too tall. You should machine them down a bit. I'd think a stock motor mount with no weight on it would be an ok reference for height. What are your thoughts? Unfortunately I don't have a brand new motor mount to measure.

Yes the offset is normal. It was apparently for right hand drive cars. It makes life easier for us though because we can fit longer straighter primary headers or a big turbo there.

If you're going as far as installing freeze plugs, you might as well fill the ACV port with quicksteel. Why? Because exhaust pulses up the intermediate plate and can contact your intake manifold resulting in some heat transfer. It's not a whole lot of additional heat, especially considering that the aftermarket manifold is simply flat right there, but after several hundred thousand exhaust pulses during a drive, doesn't it make sense that there will be some heat buildup over time? Isn't it a good idea to reduce unwanted heat whenever possible? Especially when it's an easy thing to do?

The reason I'm mentioning this is because some folks don't believe it's problem. Well, ever felt the ACV area of an intake manifold on an idling engine and noticed it's pretty hot right there? What happens when the engine is being driven hard and generating some considerable heat? This holds especially true for stock manifolds with chambers for coolant and exhaust where if you block the coolant ports, there is nothing to take the exhaust heat away other than the carb's venturi effect. An aftermarket manifold is just flat right there so the effect is less but a good rule to follow is when you block one you need to block the other. Does that make sense?

Yeah youre right those mounts are definitely too tall. Install my K&N air filter kit on the carb (the short filter option) and couldnt get my hood on! Going to borrow a buddies lathe and knock em down by quite a bit, probably some where in the neighborhood of .75".

Thanks for the info on the offset, and I like your reasoning on making things easier haha! Building a header that makes use of the space is on the to do list for sure, never understood why racing beat chose to turn the front pipe so quickly...

Very interesting point about the acv port. I never even thought about that being an issue but I can absolutely understand why you're thinking that way. I suppose it cant hurt either way if I block it off on the engine side with some putty, probably will end up helping a small amount anyways. I thought I had to put freeze plugs in, am I mistaken? Do some people just use the o rings and gasket and it doesnt leak?
Back to the ACV thing, can't say I've felt the intake temp on an aftermarket intake, first one I've head. Would be interesting to have someone hit the same point on the intake mani with an IR laser thermometer before and after blocking it off to see what the difference is.

I've got my hands on a CNC plasma cutter table now so I played around and made some brackets for the aftermarket oil cooler im using that mount it right behind the front bumper and center.
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Also made some support brackets for the radiator. Here is one side mocked up, painting them black today.
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Going to try and tidy up the plumbing (fuel, oil and water) next. Curious what size hose people are using to feed weber IDA carbs. It looks like using -AN adapter in the threads will narrow the inlet ID to the point where using anything more than -6an line would be overkill. Any thoughts? Am currently planning on running -8 up to the pressure regulator on the firewall.

Another issue I have to overcome is the crappy gilmer belt drive kit alignment that I have. The water pump and main pulley are in the same centerline, but the alternator pulley is offset about a 1/4" towards the front of the car. See in the picture how belt isn't centered on the main or water pump pulleys.
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So I figure I'll probably machine down a bit of the water pump housing and alternator mounting tab to bring everything back in line. Talked to mazdatrix about it and they didnt have an answer, maybe I have some screwed up combo of parts or the part quality isnt very good. I'll make it work somehow.

Cool project man! I'm in the waukesha area also. Maybe I will run in to you at a drift event some time this summer, I'm currently building my REPU in to a skid truck. Keep up the good work.

cool project.

for the IDA, i'm just running stock rubber 8mm fuel hose to the carb, simple.

for the oil cooler/radiator plumbing, back in the day they used to stack the oil cooler and radiator, and then run a sheet of aluminum between them to the front of the car. you adjust the height of the thing in the nose until the temps balance, you could do something similar...

Yes, still install freeze plugs. It prevents coolant from running out all over the ground if you ever need to take the intake manifold off.

Take the alt pulley off, take out the spacer and see if you can trim it a little. It might align the belt ok. I've had to deal with 1/8" of misalignment on several engines lately while doing pulley swaps. You might get lucky where 1/8" is all you need.

Or machine the inside of the gilmer down a little. Think about what happens when/if your current alt dies and you get another. You'd have to machine that one down as well which might not let you return it as a core.

Hey man, did you get a chance to see my new videos and pictures on Facebook? Last weekend was awesome. After the extended control arms my steering felt better than any fb out there. Little bit of bump steering but absolutely love this setup.

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Looking good! What do you mean by extended control arms. How much added and why does that help? I could see if you had clearance issues at full lock the longer arms would help let the wheel turn further before hitting the frame, otherwise I'm not sure I understand why?

I've been working on plumbing the car and finally finished up. Few hose clamps etc to sort out but the rest of the hoses are done and installed.

Got a pre/post inline filter setup for fuel pump. -8 line, moroso 40 micron post filter, earls little blue 100 micron inline filter. Holley blue pump

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Bent up some wire templates and searched around the back of the auto parts store till I found 2 radiator hoses I could cut sections out of to fit my radiator install. I think it turned out pretty good. I still have to machine down the motor mounts which will adjust the alignment slightly but should be ok.
Found a Earls carb fitting that adapts -6 into the M12x1.5mm inlet on the Weber carb. First generic M12x1.5 to -6 adapter fitting I tried was too long and bottomed out in the carb before sealing against the washer.
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Another view of the finished radiator and oil cooler mounting brackets and well as the oil cooler plumbing routing before I plumbed in the radiator overflow tank

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Starting to get an ignition system figured out. I think I am going to use a mallory 6AL to run the leading coils. Read up on how to do that conversion, using blaster coils and a dead ignitor for a plug adapter into the distributor.

Not sure about all the locked timing stuff etc so I'll run mech timing advance only and block off the vacuum ports I think. Opinions welcome on the topic...

Also not sure how people run rev limiters on these since the ignition box will rev limit the leading plugs at whatever setting but the stock ignition system for the trailing plugs wouldnt be hooked up to that limiter. So I'm currently planning on setting up a old autometer procontrol I have to rev limit the trailing plugs a few hundred rpm lower than the leadings... Let me know what you guys think and if I'm way off track on that one

Don't block the vacuum nipples on the dizzy. Leave them open to atmosphere. Why you ask? I'll answer by asking you a series of questions.

Do you like to drive up and down a lot of hills? What happens when you have an air chamber that is connected to your pickups in the dizzy and referenced to the outside air pressure on one side of a diaphram, but the other side is blocked off like you were thinking about doing? Now tell me how many degrees your timing will "drift" and at what altitude? Think about it and get back to me.

locked timing is kind of nice because you can just set the timing to like 18BTDC and be done. however if you actually go tune the thing, i think you'd find that it wants a timing curve, although not necessarily the stock one.

for the rev limiter, you need to be a little careful, if you're going to hit it once in a while, its fine to do anything, but if you are going to hit it for long periods of time, it is often better to not have one. the stop/start of the rev limiter can cause huge catastrophic damage. this is an engine that decided it didn't like the 8250rpm limiter FC3S Pro v2.0:&nbsp K2RD HOF

cutting the trailing plugs only might actually be a good idea though, instead of scattering the engine, you'd just get a drop in power.

This thing is looking more and more awesome by the post! Great work! Giving me tons of ideas :) thank you!