cib24

I had my first track day at Donington Park (UK) this weekend and had a very enjoyable time learning how to drive the car. However, I experienced three issues that I would appreciate help with sorting out:

1. Secondary boost problems
My car is mapped for 0.85 bar (12.3 psi) and prior to the track day I would consistently see 0.85 bar on the street. However, my issues started only 3-4 laps into the day when boost dropped to between 0.55-0.7 bar (8-10 psi) after the transition and hold there until red line. The car boosts better during the 1-2 laps before everything starts to really heat up but it still won't achieve 0.85 bar anymore.

2. Excessive oil blowby even with car less than half full on dipstick
The other issue I experienced was excessive oil blowby that filled my catch can to the maximum and ended up coating my entire intake system with oil, causing oil to seep out of the lower intercooler hose and between the throttle body and stock elbow area. I had to empty my catch can 3 times in 4 runs.





3. Cannot turn wheel more than c.70 degrees when going left at speed
The car turns right just fine and I can turn the wheel left all the way to the locking position at speeds of less than 15 mph. There is no rubbing of the tires anywhere under the arch (we checked). If I keep turning the wheel at speed and yank it harder it will let me turn a bit more but I hear a grinding sound which sounds like the power steering pump or belt. The fluid is full so I'm not sure what the problem might be.

So, any advice on where to start will be of great help.

cr-rex

iTrader: (114)

1. what kind of boost controller are you using? electric, manual, stock green solenoids?

2. how is your catch can plumbed?

3. no idea. can you go lock to lock sitting still? it wouldnt really make much sense to only have the problem at speed and not sitting still. i assume less than 15mph would also encompass sitting still but i figure i'd ask.

cib24

1. The PFC is my boost controller which controls the stock solenoids.

2. Oil filler neck to catch can to primary turbo inlet elbow.

3. Yes, sitting still can go lock to lock. At less than 15-20 mph can go lock to lock. At between 20-50 mph (haven't tested such an aggressive turn at higher speeds since it occurs in hairpins) I can't turn more than 60 degrees and get a grinding noise but no rubbing of tires and no noticeable suspension binding.

IRPerformance

iTrader: (41)

1. Sounds like a lazy/sticking solenoid or check valve. Definitely check the turbo precontrol and wastegate solenoids.

2. How is it plumbed? My oil neck would help as well IRP Stainless Steel Oil Filler Neck | IRPerformance

3. Sounds like an issue with the rack itself.

cib24

1. Yes, given the amount of oil that dumped into the inlet elbow and leaked out of the inlet elbow from my hose attachment all over the place, the oil in my air box, the oil that appears to have escaped via the lower rubber coupler on the intercooler and the oil that escaped where the throttle body and elbow join, I would assume that one of the solenoids is gunked up with oil and/or there is now a small air leak somewhere in the system because of the oily mess.

The precontrol and wastegate solenoids are covered in oil at the moment, at least from the outside but how do I test them to see if they are faulty?

2. Yes, I have been looking into something like that to help. Is there a Group Buy still going on?

3. This evening I had the car up in the air and undertray off and looked very closely at the front steering components and rack. I turned the wheel to the left little by little to see if anything was hitting, binding, etc. and couldn't find a thing.

Below is a photo of the steering rack with the wheel turned to the left about 90 degrees from center and whilst it is very close to my downpipe it isn't hitting it and unless the rack somehow has play in it which I have never felt whilst driving, I can't see how it would hit the downpipe during movement.

IRPerformance

iTrader: (41)

Do you have pics of how the catch can is plumbed?

The factory service manual tells you how to test all the solenoids. You apply power to them and it should change which way the air blows through.

Yes I have about 5 of the oil necks left.

Check your steering rack bushings and motor mounts for excessive play. Put a pry bar underneath and see how much the components lift.

cib24

Catch Can Plumbing

The catch can is plumbed in line with how the stock system is set up for oil overflow from the filler neck to make its way into the primary turbo inlet elbow. I am using 3/8" hose since the barbs on my catch can are 3/8".

Filler neck to catch can:





Close up of catch can hose





Catch can hose to inlet elbow (the one on the right with hose clamp)





I don't have a factory service manual but I'm sure there are plenty of how-to's online to test the solenoids. I hope I have the right equipment to be able to do so.

The dual AN6 filler neck would be good. I imagine I could plug one hole with an AN6 plug and fit an AN6 male to 3/8" hose barb to the other. I will send you a PM.

I don't have a pry bar but I can take my car to someone to test the rack and motor mounts although the bushings for each look pretty new from a visual perspective.

ZoomZoom

iTrader: (2)

If you have the stock sway bar mounts they are known to damage easily. The bend under normal use and are garbage for track use with R compound tires.

If you bottom the car out or hit anything or go off track into a gravel trap you will have likely destroyed your stock sway bar mounts.

When they fail they can sometimes be pushed back and can tear up a steering rack boot or cause interference.

Read this
https://www.rx7club.com/3rd-generati...t-pics-228777/

cib24

Yes, I definitely checked those out in detail last night. Fortunately, they are still good and don't appear to have ever hit anything.

cib24

Would something like this also potentially benefit alongside an oil filler neck baffle?

SuperNow Engine Baffle Plate

TomU

iTrader: (11)

This thread walks you through all the FSM tests

https://www.rx7club.com/3rd-generati...-stuff-802060/

Maybe. It's really more of a windage plate tho (used in reciprocating engines to keep the crankshaft from spraying oil all over the place). Baffles would be vertical and keep the oil from moving horizontal, but if it keeps oil from backing up into the oil neck it may work. That said, it looks like it's a good 6mm thick. This may cause some fitment issues, esp if you are also using an oil pan brace. On top of that is the cost and PITA to install. Try the baffled fill neck first and see if that helps.

Regarding the steering. One thing I don't do myself is tuning, either engine or suspension. Find a good suspension shop that preps track cars. You probably will need their services for other tweaks in the future and it's good to build a relationship.

cib24

Thanks for the link.

The SuperNow plate is actually 10mm thick! After some searching it does look like installing it would be a PITA because you need to remove both engine mounts and potentially the front crossmember...So, yeah I will try the filler neck first.

With respect to the steering, I was thinking it could be two things:

1. The steering shaft sits very close to my large Knight Sports downpipe. In left hand turns could the engine actually be flexing to the right side of the car (away from the apex of the left hand corner on the track) because of the rubber engine mounts and thus the downpipe is colliding with the steering shaft bushing bolt or the shaft itself? I have never felt any vibrations in the wheel though.

2. The power steering pump is cavitating from left hand turns. The pump is on the left side of the car nearest to the apex of a left hand corner and the fluid could be forced against the right side of the power steering reservoir and causing the pump to starve for fluid until I straighten out?

TomU

iTrader: (11)

Yeah RHD, that's gotta suck

Could the tab circled in the attached be the culprit? I don't recall a tab being on the steering shaft tho. I doubt a little engine flex will bind your steering and if it does, think it would be very momentary.

Curious if any other RHD owners have experienced this problem

And I doubt PS fluid starvation is the problem. You are not going to have enough list that air would get into the system and if you were, it would just make the power uneven (i.e. it would have no bearing on left or right limits on your steering)

cib24

I will get under the car again tonight and look at that tab and see if it gets very close to the downpipe. Any other ideas from anyone else in the interim?

With respect to the oil blowby problem, what oil pressure should I be experiencing? I have Defi gauge similar to this:



At idle I experience 2.0-2.5 which steadily rises with RPM until it maxes out at about 8.0 above 3.5k RPM all the way to redline. I run 10W-40 Shell Helix semi-synthetic.

Is my oil pressure within spec or too high? I was just thinking some more and thought if I had excess oil pressure I would have more blowby.

TomU

iTrader: (11)

8 seems a little high. From Racing Beat...

Rotary Tech Tips: Oil Cooling Tips

Does it come down when it warms up.

When your checking your steering, make sure your suspension is compressed, esp when checking the tie rods.

ZoomZoom

iTrader: (2)

Partly why IR Performance oil filler neck works so well with a catch can can be explained here.
https://www.rx7club.com/3rd-generati...ce-car-792344/

The orifice is -10AN for the catch can. Allows pressure to be relieved without taking a lot of oil with it.
Also don't vent it back into the manifold. Put a breather that will vent it and any extra oil can be sent back to the return line so it won't overflow.

Seems to be working as stated on the race car in the link above.
That's how I am setting up mine.

cib24

Actually, based on that link I think my oil pressure is pretty spot on if we assume the gauge has a margin of error. Converting to PSI I get about 30 PSI at idle and 110-115 PSI max.

Checking with the suspension compressed is kind of tough since I can't get under the car with it in the ground.

Could it potentially be a valve going bad in the steering rack itself?

cib24

Good shout but my catch can has a 3/8” barb so I will need to reduce the AN10 fitting with an adapter down to 3/8”. Or perhaps I can run a 5/8” hose from the AN10 filler neck and then reduce closer to the catch can or would that not relieve enough pressure?

Or I can just get another can but I paid good money for mine...

cib24

I went under the car again tonight and looked at that tab and it's pretty far away from the downpipe actually so I don't think that it is hitting.

I took a video of the steering shaft moving when the wheel is moved from full lock to the right to full lock to the left. The upper bushing and screw come very close to the downpipe, particularly the threaded end of the screw. We are talking like maybe 1/4 of an inch of clearance at times from that bolt to the downpipe.




Do you think that's a close enough gap that under left hand turns the engine can lean to the right side enough where the downpipe comes in contact with the steering shaft? The bolt looks like it may have come in contact with the downpipe as well by looking at it but I'm not 100% sure.

ZoomZoom

iTrader: (2)

Yeah the experience of the guy in my above link also had the issue with the small stock sized fittings. The pressure couldn't be relieved without bringing all the oil with it on hard right turns.
The filler neck IR Performance sells is -10AN. It is a proven method. I can appreciate money you have already spent. That being said... If it isn't a solution then...

If you are married to your catch can that's fine. I think you may be able to get away with it as long as you upgrade the filler neck to the IR Performance filler neck with the large -10AN outlet. It's where the oil Slosh will be and the pressure can still get by with that large orifice.

Even if you neck it down at the Catch can to your NPT fitting you have problem solved most of the issue at the filler neck itself. If it wasn't for the exact problem and solution provided I would say to try another method.

IRPerformance

iTrader: (41)

Vent the catch can. Running it inline with the pcv or inlet doesn't work as well.

cib24

Yes, I think initially I am going to try the filler neck with the -10AN fitting and use the appropriate 5/8" hose with it and then just reduce it down to 3/8" right before the catch can. That way the oil slosh that makes its way up will have a longer way to travel at 5/8" until it makes it over to the catch can which will hopefully reduce the pressure a bit on the way.

If that doesn't work then I will need to either modify my inlet barb on the catch can to be -10AN or get a new catch can with the larger fittings.

By the way, I have discovered that the screw in the steering shaft bushing is not the OEM size as the screw should be flush with the bushing and not be poking out. I have also discovered that it is in fact hitting the downpipe sometimes as evidenced below:





I think I have found my steering issue.

cib24

Alright, so I changed the bolt and also yanked on the engine to see how much it moved.

Old vs. New Bolt





Bolt is still really close





Unfortunately, I think I am going to still have the issue because the bolt head simply sits too close to the downpipe when the wheel is turned 90-100 degrees to the left from top dead center (about the same amount of anlge which was affecting me at Donington).

I also yanked on the engine and whilst I couldn't get the downpipe to touch the bolt I could get it pretty damn close to touching. I would guess that the engine probably moves a bit more during a high g corner than it does with me yanking on it so it will most likely still collide.

Therefore, I think I need to consider two things:

1. poly engine mounts from IR Performance or DM Motorsport (whichever are softer and will have little to no vibration); and/or

2. Remove the downpipe and purposefully dent the affected area a bit to create more clearance. This shouldn't really affect performance at all given the flow is already really good from the large downpipe and based on the evidence shown in this video:




In other news, I have taken off all of my intake hoses this evening including the intercooler (I had to remove the battery in order to get to a screw attaching it to the air duct...) and as shown in the photos below everything was nice and oily...Except for the crossover pipe which is spotless inside and that seems really odd to me. Oil had managed to seep out of the couplers and seemingly get everywhere on the front cover, alternator and everything below those and below the primary intake hose as well.

cib24

Very slight more clearance with a button bolt! Next step is some poly engine mounts to reduce movement of the engine and if that doesn't work I'm going to put a nice dent in the downpipe.

cib24

So I was at Anglesey yesterday and I am happy to say that changing the bolt to the round button bolt has alleviated about 95% of my steering issue! Only occassionally did I feel a bit of resistance at the Rocket and Bus Stop corners. But due to the way the bolt is shaped the wheel would keep turning unlike with the older non-rounded bolt that would get caught on the downpipe.

To permanently alleviate the issue I have ordered some shore rating 60A poly motor mounts from IR Performance along with their baffled oil filler neck to help alleviate the oil surge issue.