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I deal with o-rings all the time at work, we use viton a lot because of the temperatures of our products. That said i would recommend using NBR if you can get away with it as viton is pretty soft and damages easier especially is something is disengaging and re-engaging like a valve seat, also deforms quicker over time. They are good to around 200C (~390F), but do drop in duribility over about 120C (~250F). From memory NBR is good to about 120C (~250F), if your intake or BOV is getting up to those temps you really need to look at reducing it somehow, heat shields and wrap or something. you could try and get a higher duro NBR o-ring, will be tougher. ;)
 

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Discussion Starter · #142 ·
Here's my dyno run and dyno sheet from Import Face Off in Las Vegas.

 
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Discussion Starter · #143 ·
Well...the damage done from the drag racing and dyno was the turbo mounting gasket blew out. It was the metal shim type, but it seems that my turbo mounting bolts backed off a bit. I'll have to get into the habit of checking them more frequently and retorquing them. The poly engine mounts make the vibrations more intense, so it's just a trade off of feeling way more connected to the car vs having to recheck the bolts. The manifold nuts were not loose, but I torqued them a bit more as well when I had the turbo off. It came apart pretty easily and everything looked to be in good condition still. I sourced a new t4 undivided mounting gasket from autozone, fel pro 61789, and I used copper gasket spray on the gasket and the manifold surface to help with sealing. I got it all done over about 4 hours of wrenching total. The nut that is closest to the firewall and head is the hardest one. I used an egg-shaped copper nut so it's designed to be a pain to install and remove. Having to use a crowfoot wrench 1/4 turn at a time is tedious. I replaced the stud and nut when I did the job since I had a pack of 4 and only use 1 in the manifold. The other 3 bolts are easily accessible with an 8mm Allen key. I got it back back together and now there's no exhaust leak. I'm going to start trying to tune it with the FIC, since it's pretty rich off-boost with the 7mge injectors and they kinda piss the stock ecu off at idle if you let it sit for a long time.
 

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Discussion Starter · #144 ·
Also, there was no oil or wetness in the downpipe at all, so that's a great sign that the engine and turbo are healthy still.
 

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On you gasket. Torque it while it is hot. That should make it seat more permanently. I do that all the time with those heated gaskets when I use metal or copper.
 

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Discussion Starter · #147 ·
263hp and 246tq at 8psi peak running in the low 11s afr per my wideband
137636
 

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Discussion Starter · #149 ·
I think my next plan is to try a FMU setup with the stock injectors. I bought an adjustable fmu that can go from 1:1 all the way up to 10:1 for boost reference fuel pressure rise. I'm going to see if that makes the stock ecu happier at idle and off-boost and still provides a good afr for full boost on the stock ecu. The stock injectors worked great but leaned out at the top. I think with a higher than 1:1 fuel pressure rise that I'll be able to get enough out of the stock injectors for the current boost level. I also have a first generation aem truboost boost controller setup that I want to install and try to get it to hold a consistent boost and eventually raise boost to a peak of 10 psi. I'll likely end up playing with the FIC ignition table to compensate with some retard for the cells above 8psi.
 
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Discussion Starter · #150 · (Edited)
Update...so I installed the FMU and stock injectors again and I couldn't get the damn thing to stop running super rich on boost. I used a check valve with the FMU and tried to adjust FMU to bleed off excess boost pressure to lower the rate of fuel pressure rise, but I think that was pissing off off stock ecu because it was causing the car to run VERY rich with basically any throttle input and then at idle it would randomly go super lean just sitting there for awhile. The FMU was raising fuel pressure way to high when boost came on and it would dive into the low 10s and just felt like it was not making good power and almost had a feeling that it was loading up with way too much fuel that it couldn't burn effectively. I went back to the aeromotive FPR with the stock injectors for now set to 50psi base. This works better for idle but it is too lean for my liking at the higher rpms on WOT. It's peaking around mid 13s AFR. I'm going to try tuning that area with the FIC and see where that gets me. The 7MGE injectors seemed to work ok under boost, but they flowed way too much fuel at idle to the point where fuel and soot was coming out of the exhaust. Maybe if I can't get the stock injectors to work at the higher load areas then I'll just throw the 6mge injectors back in and try to reduce fueling around the idle and mid range areas. Ideally I want to be in the low to mid 12s AFR at redline on peak boost. Any richer and I feel that is just wasting fuel and also hurting the max power number. The car feels really strong currently, but I know boosting in the 13s AFR is not safe in the long run.
 

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It was the rate of raise on the FMU. There are different rates for different part numbers. Or did you try to use one of the so called adjustable ones? What brand and model did you use?
 

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Discussion Starter · #152 ·
It was the rate of raise on the FMU. There are different rates for different part numbers. Or did you try to use one of the so called adjustable ones? What brand and model did you use?
It was a SPA branded adjustable one. I tested the rate of rise with an air compressor and tried to lower it as best as I could to get close to a 2:1 ratio or less, but it still ran super rich.
 
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oh wow. This car motivated my low boost journey. so far so good. thank you for the informative right up.
 

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Discussion Starter · #155 ·
I would see about finally doing some tuning with the FIC.
That's definitely my next course of action. I'm going to put a new upstream o2 sensor in because it was really sooted up from running so rich with the 7mge injectors at idle and then I'll mess with the FIC tuning. I'll try to get some video of this process as well to help others who may be wanting to use the FIC.
 
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Discussion Starter · #156 ·
So I upped the fuel pressure to 60psi at idle with the vacuum port connected to the regulator. Now my AFRs at the top of 3rd are in the low 11s. The car feels faster than it's ever been. I need to try out my dragy to see what kind of times it lays down. I also plan to get it dynoed again sometime soon.
 

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Discussion Starter · #157 ·
Here's a quick video of a pull going through the gears.

 

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Discussion Starter · #158 ·
138106
Dynoed the car again today. It made 304HP/303TQ on stock injectors set to 60psi fuel pressure.
 

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View attachment 138106 Dynoed the car again today. It made 304HP/303TQ on stock injectors set to 60psi fuel pressure.
That’s pretty solid gains overall.
A few questions if you don’t mind:
1. What boost pressure?
2. what were your AFR?
3. I know you run the FI-C for fuel control but from what I recall, you aren’t even using it right? Are letting the stock ECU compensate completely on it’s own?
4. is this on the 7M injectors? What is the difference between 2JZGE and the 7M?
 

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Discussion Starter · #160 ·
Here's a video from inside the car. You can see the afr and boost reflected upside down on the glass. FIC is bypassed with the bypass plug. Stock injectors just letting the stock ecu handle fueling. the 7mge injectors were too rich at idle for the stock ecu to compensate. It was fouling the o2 sensors.

 
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