1985 rx7 1uz turbo

[twistedmetal]

hello, new to this forum but wanted to share my project since I gathered some info from here before I chose the 1uzfe as my power plant to swap in my car, i have a 1985 rx7 that i have owned for around 9 years and due to all the reasons that us rotary guys know well it was time to move to a more reliable method of propulsion since highish 400+hp wankels are not known for longevity...to say the least...

so began weighing my options and puting together a set of goals, im a gearhead from birth and a compulsive tinkerer, plus i love a challenge and just so happens im a machinist by trade so I have a make it happen outlook on projects.

the goals..
ditch the rotary to start with, love em to death...but cant afford to support them anymore.

have near or above 500whp with the added torque of a piston engine(of any kind)

to get near around 30mpg cruising

have around a 200mph top end(obviously not on public roads )

and not break down every time you drive it(see goal number 1)

and so it began....here is my car on its last rotary powered outing to deals gap NC, had a blast, combo made approx 400ish HP 12a turbo with EFI

 

[twistedmetal]

wanted a unique power plant, was weighing in various v6s v8s, even the 5.0l BMW v12...just not enough room for that one

so i settled on the 1uz rather than take the easy way out with a ford/chevy engine. the 1uz has the weight i wanted to maintain and the power capability wanted to achieve, and so far as i have found no one in america has a documented build in an FB rx7, so thats unique enough.

this engine will be twin turbo, using an electromotive tec3 engine management

oh and its under the stock un-modded hood

as of this posting i have been working on the swap for about a year, adding rack and pinion steering, 8.8 rear end, misc suspension mods, etc.

 

[twistedmetal]

i am using the mazda turbo2 transmission along with the aftermarket flywheel/clutch/press plate, since I didnt want to buy that stuff all over again, i made the adapter plate and crankshaft adapter and only cost me about 15 bucks for the hardware. pretty cheap adaptation this way.

the rotary starter lacks the testicular fortitude to roll over a 1uz so i have adapted a camry 1mzfe starter to work on the mazda bellhousing.

the T2 trans "should" hold the power I am looking to make, and since this is a road car with road tires the wheelspin will cushion the trans a bit.

i had to move the engine/trans rearward 4 inches from where the stock trans location put the engine, so it took a mildly creative method of moving the shifter housing...but that allowed the engine to go back AND down to achieve radiator and hood clearance.

 

[twistedmetal]

shim the re-speed Xmember down by 3/8 inch, make offset bushing for the steering rack, AND shorten the oil pan by 1 inch, plus add a 1x2 inch tube to the bottom of the Xmember as a strike point to achieve the stock hood clearance...but its worth it...I added provisions for a sump-guard armor plate in the 1x2 by welding nuts on the inside for 5/16 bolts and i will brace it up where needed.

motor mounts are solid and consist of a "re-arranged" stock mount on the pass side, and a billet/rod link combo on the drivers side, with aluminum trans Xmember

 

[twistedmetal]

as for the oil pan issue, I am at this time only mildly concerned with oil volume loss, as i have 2 large external oil filters and a large oil cooler being added to the system with the coinciding lines to and from probably adding more volume to the system than it had originally, but to be on the safeside for surge I will probably run the oil level a little high, I would love to hear any experiences on this matter from others that have changed the pan in this manner, Im pretty sure it will be ok since the engine holds a large volume to begin with.

 

[twistedmetal]

i modded the intake and fuel rails/intake to accept ford green top 42lb injectors simply because i got a good deal on them, otherwise i would have used a direct fit injector, also modded the rails to accept AN fittings using -6 o-ring to -8 male.

im still undecided on the throttle body, i may use a different one than stock...not sure, its a matter of function and TPS not size of TB, its turbocharged so TB size isnt and issue, in fact my optional TB is smaller than stock.

on a chassis note i had to relocate the brake proportioning valve to accommodate the head

 

[twistedmetal]

I have 2 57mm t3 turbochargers for this build, they have internal gates that i will control with the tec3 once its all done so i can ramp in boost where i want it.

i made a hub style adapter for the 60-2 trigger wheel that goes under the crank bolt using an un-modded balancer

the crank trigger is held in a billet alum bracket using one of the unused bosses on the oil pump, i dont have nor can i have AC in the car due to it being removed long ago...and now i lack the room for a compressor anyway, much less room for a condenser and plumbing...oh well...hot rods dont need AC

still working out a way to tighten a belt on the alternator...ill get to that later...this is a bare bones operation, no PS, AC or hydro fan, just alternator just have to figure out a nice belt system.

i have a fairly large radiator, the largest i could fit in the car without cutting on my car, made a custom shroud with twin fans, slightly angled it rearward to allow for intercooler plumbing to pass around it, still have to fab an intercooler to fit the space i have...which is not very much...

 

[twistedmetal]

i need to find a plug wire solution, i need the proper ends to fit the head, but i want to use a nice fat wire and i need custom lengths to put HEI terminal ends on for my coils, was thinking some kind of chrysler hemi wire maybe...not sure yet, any ideas are welcome.

the engine is essentially stock, its a 1993, polished/smoothed the pistion tops, honed the bores slightly for a little more clearance gapped the rings for turbo application, and added the lextreme valves springs, acl bearings and a new oil pump.

I saw no reason to bother with head porting and all that since the cams are stock and its turbocharged, whether that air likes it or not...its going in...and out...

had to make a little tool for the springs as ya'll probably already know...they are hard to get to...

 

[twistedmetal]

I am trying to have this mostly done and hopefully running by years end so i have plenty of shakedown time before the next deals gap rally in april, which is a 13hour drive one way...dont really want any surprises....

going to sneak in quietly under the radar of the die-hard rotary guys , great bunch of people though, rx7 guys think out of the box...im waaaaaay out of the box...

im going to be changing my final drive ratio to 3.08, which should put me at a comfortable 2300ish at 70ish, and that should get me close to my 30mpg goal with the slippery little car, and it puts it at a bravery limited theoretical top speed of 203mph at 6500 rpm...though...i value my car above my life and achieving that speed in an FB without aero mods will put the life of my car in danger and so I may or may not attempt it...maybe on a runway...

going to merge the 2, 2.5inch down pipes into the main 4 inch system, should still be quiet, i like quiet, it will have a middle muffler and rear muffler, along with the turbos. all i want to hear really is the whistle hehehe

im going to be running the engine sequentially injected, using waste spark coil arrangement, for those unfamiliar with electromotive it uses mainly GM sensors and the DFU units use GM twin post coils, easy to replace and available everywhere.

stay tuned as the plot thickens

 

[DannyR]

this is sick. can't want to hit the junkyard this Saturday. 50% off everything so my motor. harness and ecu will cost me less then $200. hopefully I can swap this is my s14 and get it on the road

 

[twistedmetal]

if you plan on using the stock harness and what not, be surgically carefull removing it, the clips and plugs are always very brittle...I am making a whole harness because i am using the tec3 unit, i feel sorry for those working on them with old heat cycled harnesses...best of luck on that 240, that will be a HUGE improvement over the ka24 or sr20, and ignor the haters...you wont hear them anyway....hard to hear whats behind you

 

[twistedmetal]

timing belt installed, working on the new belt tensioning system, and making it all pretty, incidently strips of velcro mimic a serpentine belt pretty good for figuring out what you are going to do and how long the belt is going to be.

i have to dissect the stock spring tensioner...looks like that might be a dangerously amusing good time, then will mod/fab/machine accordingly and then i can put the darn thing in the car!!! then plumbing...yay....

 

[milisakeracing]

Love the build. Use to own two '83 GSLs. I know what you mean about the aero prep for high speeds. The wedge shaped front end of the FBs tends to cause the front to get scary light a bit above 100. You will need to get some aero on the front to cause some down force yet not create so much drag that it significantly lowers your top speed. Good luck with the new build, can't wait to see the numbers you put down with this monster!

 

[twistedmetal]

aye that lightness in the front is the stupidity governor.....its probably best i leave it be...as it lets you know when you are being a moron and need to slow down...

 

[xspsi6]

Wow!! This is way cool! I have owned 6 1st gen rx-7's so yea I know how reliable they are not

 

[twistedmetal]

yeah buddy...add turbo and a heavy right food and watch what little reliability they had go completely out the window, that said, I am going from an engine with zero low end torque and fictitious longevity to an engine with gobs of low end and uber reliability, marred only by the addition of twin turbos, but as long as we dont make any mistakes while tuning it, should still last 100k or more. if the engine lives as long as the timing belt making max HP for the internals I will be totally happy, since its not a DD it will probably last the rest of my life.

 

[twistedmetal]

here is the new tensioner set up, i managed to get a 29.5" 3 rib belt to fit the set up, and i have on order a 6 rib which i dont have yet for pics, but it seems to work ok, i could have put a little more arc towards the tension side but im not sweating it, it will work nicely, considering i built it in one day totally out of my head without the engine with me to fit it on as i went it came out pretty nice i think.

off to the next adventure

 

[twistedmetal]

got my alternator belt in and sorted out today, works nicely, have to finish putting valve covers on and pressure wash the transmission and add new fluid and it should be going in the car as a unit very soon, maybe within this week, i will finish the intake stuff with the engine in the car, i need to start the hot side plumbing ASAP and i need it in the car to do that.

thats all for the news...

 

[twistedmetal]

engine is back in the car now, doing the finish work on the intake and water cross overs in car, working on an oil distribution block at work to run to the filters and cooler and clear the steering rack.

oil pan is level with the Xmember now as is the trans adapter so once its all done the skid plate will protect it as good as it will be able.

clearances to the rack are very tight, as is the brake booster to valve cover, but it misses and thats good enough for me.

ordered my intercooler and just picking off problems and solutions one at a time now, bit by bit.

 

[twistedmetal]

progress update, headers are fabbed and turbos hung in place to begin plumbing down pipes and intake piping, intake is bolted down now, just have to finish the throttle body and install it.

ill probably end up using a free standing IAC unit with a GM motor and billet housing so i can put it where i need to and run lines to it

still have to detail the underside of my hood before installing on car, then i can monitor clearances as i finish it out.