Generation Specific > 2nd Generation Build Thread

1988 Turbo 'Vert Project

(1/44) > >>

toplessFC3Sman:
This is pieced together from a couple places, and over a number of years, and is still on-going.

I bought the 7 back in the winter of 2004, and she started out as normally aspirated like all of the convertibles in the US. The day I bought her:


147 crank hp in a car weighing in at approx 3000 lbs was just not cutting it though, so the upgrades began as time and money allowed. As she sits as of Early June, 2008 (about a year after I moved out to MI, she's still my only car at this point):

Powertrain: (Didnt really need the engine swap... but wanted it!)
Full S4 turbocharged engine (rebuilt) and drivetrain (including pretty worn clutch-type LSD) running stock boost of 5-6 psi
Ported wastegate (to avoid boost spikes with the laughably small internal WG)
Racing Beat cat-back exhaust (love the sound, and the unit that was on there was really rotted out anyway)
3" Downpipe, midpipe and main cat replacement pipe.
Corksport FMIC and piping
Generic aftermarket intake cone filter
MegaSquirt engine management system (self-assembled and tuned)
Innovate LC-1 Wideband
1000cc/min secondary injectors (to support more boost in the future)

Suspension:
Eibach rising rate springs
Tokico Illumina shocks
Solid bushings on the front suspension
Front strut tower brace
16"x7" S5 Turbo wheels in Kumho Ecsta ASX rubber

Braking: (not much was needed here, 5-lug FC brakes are very capable units)
Cross-drilled and Slotted Brembo blanks
New pads
Stainless Brake Lines
DOT-4 fluid

Appearance: (not been my first priority)
New convertible top
Sealed beam to removable bulb headlight housings
Re-skinned seats


Thats where the car stands right now, and I'd estimate she's putting about 200 hp to the wheels. However, everythings been built with the goal of turning up the boost in mind, all thats needed is a boost controller (and probably an EGT gauge and probe to help with ignition tuning) to hopefully put down somewhere between 275 and 300 hp as a final goal for this car, power wise. I also have a Torsen LSD sitting around waiting to be installed that I just haven't gotten around to yet.

After the mechanicals are all finished up, then it will be time to start addressing the cosmetic needs.







Where I worked on her at my parents place in NJ before moving to MI, as well as when she popped the coolant freeze plug there on a visit over christmas break (yea, its late-spring in the pic, I didn't have time to fix her until then when I made it back out after classes)

toplessFC3Sman:
September 2008:

First, on inspecting the brakes, I realized that one of the slider pins for the rear calipers was snapped off and the caliper had twisted, which had thoroughly destroyed the pads (about an inch of pad material left on one side of the pad, nothing on the other), so I got a complete set of Hawk HPS pads and a new rear caliper. At the same time I replaced the Master Cyl since it was having some intermittant problems with the seal/valve separating the reservoir from the cylinder, and found that I needed to replace a front caliper too because of frozen pistons. So, more than half the braking system is rebuilt or new, and the remaining two calipers were still in great condition, so I didnt touch them. At the same time I also painted the brake calipers black and the wheels a graphite-color.

Next, I got a fuel pressure gauge and a boost gauge from Prosport since their gauges matched the Innovate G3 wideband gauge I already had, and the autometer boost gauge was pretty inaccurate. I got the fuel pressure gauge to try to diagnose a seemingly random stuttering problem I had on occasion (which happened to be due to air in the fuel lines that was just stuck at a local high point). However, once it was in I discovered that the Walbro 255 lph fuel pump was completely outflowing the stock FPR, and the rail pressure was hanging out at an almost constant 60 psi for the past 2 years. Unfortunately, that meant that the fuel tables in the tune i'd been working on since then would be off by a little bit and would need to be re-tuned once I got an FPR that was capable of flowing enough fuel.

Around the same time, I relocated the wideband's body from the transmission mount to the chassis, since the transmission's heat and vibration during a long drive seemed to be affecting it. Since moving it, I've had no problems whatsoever with the LC-1, even with the 600 mile drive from NJ back to MI.

Which brings me to the most recent mod... an Aeromotive A1000 adjustable Fuel Pressure Regulator. I needed an assortment of AN fittings and an impossible-to-find metric adapter to thread into the end of the fuel rail. It didnt help that Summit messed up my order (and recommended o-ring fittings that didnt actually come with o-rings) 2 times, but oh well. Anyway, I decided to install the FPR on saturday, the day before an autocross. This involved taking the upper intake manifold off, which isn't that hard to do; i've done it at least a dozen times before. Anyway, all of the fuel system stuff goes well, and the FPR gets plumbed up in under an hour. Now time for reassembly.
As I'm bolting the UIM back on, the bolt (an M8x1.25, 90mm long) that goes right in the center snaps in half under the lightest of pressure. "Shit, I must have overtightened it last time and stretched it". Well, off to the hardware store to try to find some way of replacing it. The only metric bolt long I could find that was enough to replace it was an M10x1.5, 100mm long, so I'd need to drill out the hole and re-tap it. There are no outlets anywhere near my carport; i would have needed at least a 200 ft extension cord (if not more) to get to it, so I had to buy a cordless drill and borrow taps and bits from the lab that I work at. Well... its 4 pm, I want to get the car back together and ready for the auto-x, but now I'm stuck with an un-charged drill that has just about no power, and no time to charge it if I want to work while its light out. I tried just using the drill bit in the tap handle and spinning it by hand (with marginal success), but it would have taken forever, so it was time to get creative. Hmmm... 12v drill... 12v car battery... let me find some wire. And it worked fine, allowing me to drill out the area to be tapped as well as the hole thru the UIM that the bolt needed to pass through pretty quickly. Well, with that done, I put the UIM back on and began bolting up the throttle body.
Just my luck, as I'm tightening the last nut holding the TB to the UIM, the ratchet slips and breaks my intake air temperature sensor. CRAP! It's now 6:40, and I need to find one of these things fast! Parts Galore out off of 8-mile in detroit has a few 2nd gen RX-7s, maybe they'll have one. I was able to get Andrew to drive me out there, and we arrived at 7:27, with enough time before the posted closing time of 8 pm to grab the part, pay, and get out of there. Except... whats that note on the door... As of today, Parts Galore will be closing at 7:30 instead of 8. And no amount of asking nicely/begging/pleading was going to get us in. Time to turn back around and think of something new.
Hmmm... Pal has an RX-7, and is no longer using his rotary, maybe he'll have one. So Zach gets a few frantic texts asking for his number, responds quickly, and I leave a message for Pal. He gets back to me quickly too, but isnt sure where it would be if he still has it, and won't even be home to look until after midnight, so that path won't work. (Thanks again for your help though, Zach and Pal!) At that point Andrew and I decide to go to the meet, and I'll just either run with a bunch of resistors in place of the IAT sensor, or try to fix the broken one. The car will have to wait til the morning of the autocross to be put back together, have the tuning adjusted, and everything troubleshot... cutting it close.
Fortunately that night, someone on MIrotaryclub.net responded to my frantic plea for the IAT sensor, had an extra one, and was going to the same autocross! (Rotaryrescue - very appropriate name - you are AWESOME!!!) So all I had to do was get the car there, for which a very slap-dash, hacked fix to the broken IAT sensor was necessary.
So, the next morning I'm out in the rain re-assembling, and on the drive there I'm trying to tune and make sure I'm not going to be running too lean at full boost on rt 14 in the rain and traffic, while having andrew and three other friends following me to the autocross, wondering why the hell i'm driving like a madman. Oh well, it was completely worth it. By the end of the drive, the car was running pretty well (if a bit rich), and I was able to compete in the autocross. I've done a little bit of tuning since then, and she's running just about as well as she ever has.

toplessFC3Sman:
Nov 23rd, 2008:

Well, just got thru the most recent batch of trouble, this time with the Megasquirt. The whole time i've had it, i've been using the MS1 processor, which is a motorola processor circa early 90's. The MS2 processor is basically a direct replacement, and i've had it sitting around for almost a year, but the code for it hadn't progressed to the point that it would work well for a rotary until about a month ago. I got my hands on a bit of the alpha code for it, and tore into the MS to make the necessary changes.

Somewhere along the line, I shorted something out accidentally, and then my secondary injectors stopped working, so I was limited to under 110 kPa and under 4k RPM (I could have changed this, but thats about where I run out of fuel with the primaries anyway). Well, back apart it comes, just to find one of the traces in the PCB has been burned up (yep, thats where the short was...). A jumper wire later, and the secondaries are working again, but now for some reason the car is running rich as all hell, and all attempts to correct it do nothing. Same pulse-width as before, but now the car is at 10 or 11:1 AFR, not 13-14. However, it was somehow still drivable, so the amount of fuel was changing with load and speed requirements. It wasnt a bad reading on the wideband, it really was on the ragged edge of drowning itself in fuel most of the time. Well, I re-checked all the connections, tried it with both MS1 and MS2, replaced a couple of the power transistors, and still the same thing. Leaned out all the maps so that the pulsewidth was basically just the injector opening time, still running rich. Brought it inside and hooked it up to the oscilloscope, but the output pulsewidth was exactly as reported thru megatune and responding fine. Hooked it up to a relay coil and 12V to simulate the inductance of an injector, and the output was still fine, yet it didn't work on the car. I need the car for a trip back to the east coast on Tues, so its desperation time. I just went thru and replaced most of the components in the injector circuits that I had replacements for, and miraculously... IT WORKS AGAIN! Most of what I replaced was in the flyback dampening portion of the board, and I suspect that one of the mosfets in there that was failing with the higher flyback voltages, allowing the injector to see ground for longer than it should and staying on for longer. Unfortunately in the period that it was running very rich, I think i burnt up my wideband O2 sensor, so i need to run around and find one tomorrow to replace it. But at least IT RUNS!

And for fun, this was my workspace, with the MS, my computer running megatune, an O-scope borrowed from the autolab, the stimulator card, and a power drill taped to the crank angle sensor to simulate engine RPM.

toplessFC3Sman:
Jan 26, 2009:

Well, next installment time... since the pilot bearing is shot, the transmission needs to come off again to replace it. However, if it's coming off, I may as well replace it with a transmission that has working synchros in all gears, and doesnt whirr away in 3rd and 5th. Found a J-spec one from a reputable dealer on the 7club, so hopefully I can recieve it and finish the work in time to take the 7 out to at least one of the ice races and get some use out of the snow tires!

Feb 1st, 2009
Considering the "good" weather we had today, I decided to get started on the transmission removal, even tho I don't have the new one yet. Pulled the exhaust, underbody brace, and drive shaft in preparation, until the above-freezing weather melted some snow uphill from me and it turned into a nice cold stream running right thru my shoulderblades. I'm ready to pull the transmission, replace the pilot bearing, and throw a new tranny in there now tho.

Feb 8th, 2009
YES!

Transmission is out, pilot bearing was completely destroyed, but the inner bore of the E-shaft that it sits in appears to be fine. Just gotta wait to get the new trans, then it can start going back together Very Happy

Feb 11, 2009
shifter and tranny mount come on friday, and the trans should be here on monday! Going to finish up making the pilot bearing puller today, and hopefully in another week or two she'll be road-worthy again!

Feb 15th, 2009
got the transmission, hopefully it'll all go back together next weekend.

Feb 16th, 2009
Well, as far as pics go, i've only got these two right now from the most recent bit of work, but i'll try to remember to take more as I put her back together

This is the tool I made to screw onto the end of the autozone rented slide hammer to pull the pilot bearing. Its basically just a collet machined to the inner and outer diameters of the bearing, then threaded so that the teeth are forced outwards once its in place by a bolt. on the other end of the bolt I needed to weld a nut of the proper size for the slide hammer.





Note: at this point, we got a lot of snow... the parking lot got plowed and it was piled up a little bit uphill of the covered parking structure.  The days were warm enough to melt some of it, it ran down through the covered parking spots & refroze, essentially making a thick layer of ice that got so thick that at one point, the wheels appeared to be back on the ground (even though it was still on jack stands), and I couldn't slide the new transmission under it or really get under myself.  At this point I decided I really needed a DD, and took some money I had set aside to get one, so work on the 7 slowed a bit.

March 20th, 2009:

It finally melted by this past weds, and on thursday evening, after 2 hours of benchpressing the transmission, its back in!!! Now just have the slave cyl, driveshaft, heat shields, exhaust and shifter to put back on. Some pics of the car and ice, and this was nowhere near the worst.

toplessFC3Sman:
April 6, 2009:
Well, the transmission is in, the whole drivetrain is back together, and the exhaust is mostly hung. I just need to bolt the mufflers to the back of the y-pipe, but it sounds damn good right now (loud as hell, but yea). Also, one bolt on the underbody brace broke and is stuck in the hole, and the other hole in that location stripped out, so i need to get under her with a drill and tap and clean that mess up too. Other than that tho, she'll be drivable very soon. She started right up on the first try, and the new transmission seems to be golden.

In other news, just ordered the parts to build an add-on EBC for the megasquirt so i can finally up the boost on her.

April 23rd, 2009:
Since sunday's supposed to get a little bit of rain, i had the potenza's thrown on today as well as an alignment. Got to do the first bit of top-down motoring of the season too, and am currently waiting for the wing mirrors to dry so i can put them back on the car. Then its off for a much-needed wash.

It was pretty interesting transporting the tires, since they just barely fit in the car. I loaded them up, then realized that the only gears i could get the shifter into were first and second, and fourth if you gave the tires a good shove, b/c of the tires on the pass seat. So I had to push the car out of the parking spot, and then drive carefully down to firestone (i have lifetime alignments there and needed one since i replaced the tie rod ends) to get them taken care of. She's running well though, and i've fallen in love with the engine note all over again.

July 14th, 2009:
Well, MS2 has permanently installed for the past 3 months and is working great! I finally got megasquirt's electronic boost control installed all the BC issues sorted out; now I just need to tune the PID settings for it and possibly adjust the target boost table at partial throttle for more predictability in corners, but that shouldnt take too much longer. She finally has some of the outright speed that her engine note promises, and is definitely fun.

Aug 23rd, 2009:
Whelp... the turbo has decided to destroy itself and blow all manner of oil smoke out the back, so time for another one. I'm throwing on a spare stocker I have for a little, and then its GT35 time...

Navigation

[0] Message Index

[#] Next page