Tales from the Batcave (RX-7, rallycross, misc. stuff content)

In reply to Pete. (l33t FS) :

Good thoughts to you.

Damn, it even looks better on 17s.

Reminds me of a modified Cefiro that I saw once.  In a good way.

This means it still runs and isn't puking any coolant?

Not puking coolant, and maintaining oil pressure, yes.

It has a new habit of a floating idle sometimes, and I have hit boost cut in 2nd gear twice.  Need to go in and connect up the scantool to see what all is up with that.  Not sure if this is a mechanical fault or an issue with running a 9.0:1 2.4l on a calibration for an 8.5:1 2.5l.

Had the code for the rear O2 missing, low oil level, and a whole host of fuel trim codes.  Low oil level happens when I clean the oil pan in the parts washer, apparently the float absorbs water and gets heavy.  The low oil light stopped coming on after three trips.  Fuel trims...  I can't make heads or tails out of Volvo specific fuel trims without a refresher course, but it looked like all of the long term trims were mainly awful at the idle end, suggesting vacuum leak.  I cleared the codes and the engine instantly started running like E36 M3.  Lean stumbling, missing, the works.  Plugged in my handy generic scanner and found short term trim was pegged at 25%.  *sigh*  Okay, pull airbox out, connect smoke machine.

The FU banjo is somehow two turns loose.  Getting to that without pulling the intake, which requires pulling the thermostat housing, will require removing the dipstick tube and fan.  May as well pull the over the engine charge pipe and the R injector cover and smoke test more thoroughly.

Removing the injector cover revealed that the evap hose that goes to the top center of the intake is broken almost in two.  Yeah, that'll do it.

Well, that fixed the fuel trims.  But it is still surging at full throttle around 3500-4000rpm in second gear.

It's not a boost cut, turbo pressure never goes over 2050hpa, actually a little lower than before, and the boost solenoid stays rock steady at about 58%.  Throttle position stays around 99%.  Fuel pressure is solid.

Trans isn't slipping, measured gear ratio stays at 2.38:1.  Torque limiting never comes into effect.  (Interestingly, calculated torque goes as high as 319 ft-lb)

I guess I could try looking at ignition timing next.  If it's a timing issue, I'd be surprised, as while the mapping is theoretically going to be overadvanced (same mass airflow in a smaller cylinder means higher pressures, and timing should be dialed back) I am also running 93 on a tune calibrated for 87.

Oh yeah, here's a shot of the current draw on the RX-7's injectors.  This is with PWM engaging after 1ms, and 30% duty cycle thereafter.

That is NOT the waveform I was expecting to see!  I was expecting to see a 4 amp peak, not a barely 2 amp peak.

The ECSs are awesome.  The increased grip does highlight the Volvo's understeer, or maybe it's lower slip angles at near max grip.  Did a few off ramps where I could taste the rubber in the air and there is no noticeable tire wear, unlike the Goodyears that I used to run.

The only thing that sucks is maintenance throttle is now WOT.  That was a problem I had in the Quantum too, but it was on dried out 185-width snow tires...

Swapping rear street tires on the RX-7 for less dried out ones, another stud galled.  Berk.

on to the Volvo.  Swapped the OE downpipe in, with the "angle adaptor" on the rear O2.  Then built a zero-flow adaptor for wastegate solenoid bleed hose, so I don't have to leave it unplugged.

Not "fixing" things, but fooling the computer into being happy.  The car is plenty fast on base boost, and the ipd downpipe is an NVH nightmare.

.....Huh.  When I installed the ipd downpipe, it didn't really feel much faster, or boost onset was better.

Stock downpipe back in.  Car is MUCH more powerful, mid range torque is crazy, and the turbo is a MUCH greater particpant in things.

Huh.

Need motivating.

BEERRRRRRRRRRK wiring

Fusebox is the Megasquirt fusebox I added in 2009ish.  It was powered by the wire that powered up the 12A's emissions computer.  Now, that wire switches a relay that is powered by a 12 gauge wire from the battery.  Also, am going to run with no PWM, so I put the injector resistor box back in.

So, that trans that was worn and started "racking" badly after the fuel filter incident.

5th driven gear has .027" of axial play.

5th drive gear has .013" axial play.

This is the awful buzzing in 5th gear.

Synchro splines for 2nd gear and slider are worn, not as bad as I have seen but bad enough that I had to hold it in gear the last few rallycrosses.

Buut the kicker, the thing that was getting ready for this trans to shred itself internally.  The bolts holding the bearing retainer were backing out.

Untouched from when I opened the trans:

I think I will go back to pulling transmissions apart and Loctiting these bolts before putting them in the car.  I have had two back out, one fell harmlessly and stuck to the magnet.  One went Blendtec in the gears and neither party won the battle.

I'm scrapping these internals.  2nd is done, the easy way to replace 2nd involves getting another trans...

Good thing I brought you 5 transmissions from Florida last year 

In reply to Patrick (Forum Supporter) :

Three,and I am assuming at least two are bad.  Used parts and all that.

In reply to Pete. (l33t FS) :

Four?  I thought i had 2-3 from stampie and 2 from whats his face.  There's probably a picture way back in this thread of them in the volvo trunk.  
 

edit:  

In reply to Patrick (Forum Supporter) :

One of those is an RX-8 trans, which is useless for this car for many reasons.

Well, today happened.  Now that the Volvo is more or less fixed and reliable, I'm off to spend the money on the RX-7s that I was going to spend over the winter.

Both cars are getting engine swaps.

And, of course, I was offered a complete, running 12A pulled from a car for an RX-8 engine swap.  The timing is always a bitch.

Pete. (l33t FS) said:

And, of course, I was offered a complete, running 12A pulled from a car for an RX-8 engine swap.  The timing is always a bitch.

So now you are going to plop that 12a in the red one and go straight to rallycross?

In reply to EvanB (Forum Supporter) :

No, I think the next thing I am going to do is pull the engine out of the Quantum.

Wait, there is still an engine in the Quantum?

Maybe you need that bellhousing I have to put that engine somewhere else...

I need to pull the engine out so I can verify the bores aren't rusted all to hell.  And it's going to be the easiest way to find TDC for installing the 60-2 rear main seal.

Really, I have everything needed to make the Quantum running and driving except for the computer.  And pulling everything apart so I can put all the bits together.

If the bores ARE rusted all to hell, I have that MC2 bottom end.

I have another RX7 trans here.  Discovered it last weekend.  Had to think for a minute to remember what it was and where it came from.  Want it?