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86 RX7 with Turbo LM7 and Megasquirt

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Surge can overload the thrust bearings and cause the thrust surface to "jump" the oil wedge. This flow reversal can deflect the shaft and if conditions are right precipitate a rub. Generally it occurs in the inducer radial region. An ultra-quick stop can bend a shaft also.... This could happen during surge if the thrust bearing oil wedge is jumped, and the bearing acts in conjunction with the airflow reversal to "brake" the wheel to a stop while the turbine is still getting inertial drive.


A bent shaft and imbalance will usually overload the journal bearings. Thrust bearings are in effect when on load and when surging. Balance should not effect them whatsoever.


Teflon tape is STRICTLY forbidden on most manufacturer's high speed rotating equipment these days. I have a long PowerPoint on sealants and assembly instructions basically stating Teflon Tape was miracle stuff in the 60's..but it's time has come and gone. Use nothing but Loctite 567 PST or other permutations for sealing threaded connections!


The Long King Equipment Warehouse Yard in Songjiang Shanghai is littered with rolls and rolls of Loctite 55 Teflon Cord thread sealant from me taking it out of our assembler's tool kits and throwing it over the fence! Those shards will get into the bearing and destroy the oil wedge, wrecking a machine....if they pass through unless you examine the return lines and sump VERY carefully you will chalk it up to something else. It's. Not so much "clogging" that is the issue, every manufacturer warns about the "teflon strings" that get cut off on sloppy installation and float freely into the high-speed rotating journal-bearing area. It screws up oil distribution, or in extreme cases actually wraps around the shaft! I go so far as to tell the piping contractors on site no Teflon on the water side, either...since big threads get into our oil coolers and plug up the works.


All arguments for proper application aside, the basic fact is anaerobic sealants are more reliable on threaded fasteners with absolutely no downside whatsoever... There is no reason to ever use Teflon tape to seal a threaded union any longer. The only place I concede it's usage these days is wrapping the un insulated junctions of Bently 3500 Vibration Probes!


Insofar as. Oil return goes, if the oil return is below the oil level, it will render the crankcase pressures you may experience moot. This is the case for crankcase breathers at least. On most high speed rotating machinery, the oil cream (whipped with entrained air) is returned over a surface plate to give the oil time to de-aerate before running into the sump. At worst it dumps atop the oil and "floats" while dissipating. This is where you make the return point as far away from the oil pickup point as possible so as not to suck up whipped oil into the pump for obvious reasons.


Hope this shed some light on what may have happened.

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Thanks Tony.  I now use a proper thread sealant on all tapered fittings.  


Update pics.  Some of this is mock up. I installed the 34327 radiator up front and remounted my PG cooler.  I kept the taurus fan with this new radiator and the new location.  I replaced the plastic heater hose tee with a metal one.  Installed hood pins.   I threw together a quick junk bracket so I could get started on the hotside fab.  Everything is clearing good with the hood.
Whats left before the car starts:
Weld in drain fitting to timing cover
Here is the last pic I took before the turbo install started, shows old radiator placement
Here is new radiator placement
AN -12 pushloc disassembled to be welded into the timing cover for oil drain
Drivers side hot pipe allowing clearance for power steering connections
Symmetry went out the door in favor of placement for everything, exhaust, WG, intake piping, room for stainless heat shield
Subtle exhaust
Dual DSM BOVs 
Hood Pins

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MS3 is working very good for me.  I have not had a chance to get the idle air controller working yet.  I would like to experiment with a boost controller at some point and set up at least the tableswitch input for E85 and pump gas via a toggle switch.  I don't know if I want to mess with the actual ethanol sensor for flex fuel vehicles.  I think two options would be good for me for fuel.  Hey, you are not too far away from me.  We need to meet up some time.  I'll let you know if I'm headed your way this summer.

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Made a tool to hold the balancer using a couple hardened 1/2 bolts through a large piece of angle.  It works great using a clamp to hold it up against the balancer.  The end catches the frame rail to allow loosening and final tightening of the balancer bolt.  This was my most dreaded job because I didn't have a good way to hold the engine and work the bolt being by myself.  I do have one of the pieces of all thread and a large thrust washer for installing the balancer that I made years ago when I swapped from LS1 to 5.3.









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OK, put everything back together.  Primed oil to the turbo and fired it up.  Just let it idle until thermostat opened.


Oil feed:





Engine View:



Start up vid, this was first try at startup after setting for one month.  PC680 battery and stock LS1 starter.  ASE needs a little more tuning, it almost died once.



Another vid of idling:



Looks like I will try a drive tomorrow and check the base WG setting.  

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Installed the turbo blanket.  Wrapped the hotpipes and downpipe.  Recirculated my WG output to the downpipe.  Changed the couplers on the universal radiator hoses to silicone with t-bolt clamps.  Boost is still 3.5psi.  Made a couple runs in the car and everything looks good.  No leaks and the exhaust exit in front of the front tire is as quite as my granny's park avenue, haha yeah right.  I did some very scientific testing of turbo spool.  From an idle, no trans brake, no foot brake, just floor the pedal and 1 mississippi...2 mississippi...boost.  That is same result as spooling with the t-brake.  Above 20 mph and it is 1 mississippi...boost.  


I need to fab a cold air intake next.  With no hood and the filter setting behind the radiator I am seeing 120 intake temps with ambient of 60.  Then 150 intake temps at boost of 3.5psi.  The plan was always to have cold air ducting, but it is good to see the high temps that occur behind the radiator to justify it.  Once cold air ducting is in place I will turn up to 7psi and tune.  I am planning to set at this stage for a month or two and shake out the bugs.


I did receive my lingenfelter oil cooler adapter.  An oil cooler is the next highest priority on my list.  Then smaller projects like PCV, tableswitch input for E85, AN radiator hoses, radiator ducting......


updated clamps:



updated coolant bleeder:









Recirculated waste gate:




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I purchased two coolers from silicone intakes.  A type 108 to use for the transmission cooler and a type 114 to use as an engine oil cooler.  Note that the type 114 maintains the flow of the AN -10 oil cooler lines, while the type 108 has smaller holes connecting the end tanks so it would be a restriction.  I also ordered 3 gauges for oil temp, trans temp and cyl head temp.  I am curious to have a cyl head temp in addition to the water temp gauge to hopefully give an early indicator if I lose coolant.  

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Got my toggle switch set up so I can switch between pumpgas and E85.  Tried it out yesterday.  Drove in to town on gas and ran the car down to empty.  Pulled in the station and filled up with E85, took 14.5 gallons on spec 16.6 gallon tank.  Started the car quickly on gas setting, not letting the fuel pump run any amount of time, then flipped the switch to E85 when it started leaning out.  About 2-3 seconds after starting.


Worked great.  Tuned the car on the 30 mile drive home for E85.  Now I have two set of tuned tables that I can switch between.  I took the car out and tested the wastegate setting without vacuum reference, 9psi.  


Short vid:

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Yeah, my wife was most impressed with how much faster it is at 9psi than it was at 3psi.  In low gear (powerglide with 3.08 rear gears) I am just a little scared its going to scoot the rear end out.  I am only running 245 nittos right now.  Fasted car I have owned yet, now I need to learn how to drive it  :icon46:

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Thank you.  


I have also never had a stereo system in any of the cars I have owned.  This weekend I will be installing one, I have an Alpine head unit, 4x Inifinity Kappa 6.5 components, an MTX terminator dual 12" sub box and a Soundstream Tarantula 5 channel 950 watts RMS amp.  I can't wait to hear/feel this system. 

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Got my adjustable watts link and adjustable control arms installed over the weekend.  Now I can center the rear axle and align the thrust angle.  The old non-adjustable links worked for some test driving, but I'm sure the alignment was not very good.

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Finally finished up the rear axle alignment.  It took me quite a while to develop some processes for levelling, centering, squaring and testing the watts link.  I have to clearance a couple brackets to be able to get to the lock nuts on the LCAs.  I put a couple lug nuts on each side to keep the brake rotors in place and then used a dial indicator to measure how well the watts link keeps the rear centered throughout the travel.  At first the proportion of the two watts links seemed to be off with regard to the proportion of the arm that is mounted on the axle.  After adjusting the proportion of the two links the rear stayed centered all through the movement of the axle (up and down using the floor jack).



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