Procharged 1992 SC400 "Fish bracket setup"

[spf_lexus]

Does anyone know if 15:1 is fairly safe for low throttle cruising? Sometimes I even see 15.5:1 for a split second. I can drive FI while I wait for my new FMU but njeed to know the limits. I dont ever hear detonation at that lean but inbious a WOT pull would.

 

[lexplay]

That sux about the FMU failing. can i ask how much boost your running at the moment? so are you running 15:1 with no fmu or reg?
i got a vortech 6X100-001 coming for mine, stuff knows how to use it yet though, shouldnt be too hard. i might put a fuel pressre gage on it

 

[XR8tt]

Light cruise or very light load it's ok..
Keep in mind these engines possibly have fuel cut on decel ??
From my experience with FMU's failing..
This is not new .. Often results in engine damage..
Why I prefer other means of tune...
Either extra injectors upstream or editing / fooling ecu etc

A larger plenum helps with even distribution on forced induction engines..

 

[spf_lexus]

Thanks for the afr tip. As far as getting it tuned I really do plan to get it done the right way. I have a friend sending me his vortech unit to borrow. I have a brand new adaptronic e420c w/ harness and both GM sensors. Im supposed to be graduated in August so once im done with school I plan to wire this up. I have read the wiring diagrams a hundred times over and do not really fear this install. I also already have my wideband installed and had andy @ adaptronic re-flash their WARI software to accept 0-5 volt autometer widebands.

With that in mind I also plan to swap in a set of 440cc injectors that I already have which should be just right with some room for more boost in the future.

 

[spf_lexus]

Does anyone know if the stock 1UZ fuel pressure sensor (1-wire) will work with an autometer oil pressure 0-100psi gauge? I noticed both are single wire sensors and if I can chain the 2 together I wont have to modify the oil system at all.

Also, does anyone know the maximum operating oil pressure for the 1uz?

 

[spf_lexus]

Decided that the combination of an X pipe and magnaflows was just too quiet for me. At idle its almost as quiet as a stock SC. I sort of gambled when I ordered 2 non name ebay canisters for $30 a piece but overall I LOVE the sound. 3 years back I bought a titanium JIC twin spartan exhaust for my LS400 and I swear the sound was borderline exotic. I crashed the car and destroyed the exhaust and ever since then I always wanted the canisters back on. The only way to ever improve my system would be to swap my magnaflow X pipe for a Burns stainless.



I always get my exhaust work done by the small shops. The single guy operation that made my original system only charged be $150 to assemble a bend kit + muffler kit that i provided. I just had these swapped out by another single guy operation out in colorado and charged $40 to swap it out. Im a DIY to the bone type but I do appreciate clean welds and my lincoln electric just cant make the cut.

 

[spf_lexus]

That sux about the FMU failing. can i ask how much boost your running at the moment?

I know its probably not the safest but I upgraded my 3.4" pulley that provided 7psi to a 3.2" pulley that gives 9psi. I also need to add that my MAF sensor has failed so a week prior to the fire. Im essentially running off the ECU's use of the TPS sensor. Its amazing how many subroutines the stock UZ ecu has. it has a seperate modified tune stored in case any sensor fails (not all but most). Because I have a wideband I can play with the TPS sensor and essentially play with the AFR because the ecu does not have a second sensor to reference from such as the maf sensor in my case. If I almost max the sensor out I get 15.5afr and when I lower it 3/4 of the way it drops to 11-12:1. I used to be pretty scared of ecu wiring and tuning but as of now I cant wait to give the adaptronic another shot.

 

[erikbang]

I know its probably not the safest but I upgraded my 3.4" pulley that provided 7psi to a 3.2" pulley that gives 9psi. I also need to add that my MAF sensor has failed so a week prior to the fire. Im essentially running off the ECU's use of the TPS sensor. Its amazing how many subroutines the stock UZ ecu has. it has a seperate modified tune stored in case any sensor fails (not all but most). Because I have a wideband I can play with the TPS sensor and essentially play with the AFR because the ecu does not have a second sensor to reference from such as the maf sensor in my case. If I almost max the sensor out I get 15.5afr and when I lower it 3/4 of the way it drops to 11-12:1. I used to be pretty scared of ecu wiring and tuning but as of now I cant wait to give the adaptronic another shot.

Very nice! Exhaust looks great! I noticed you've decreased the pulley size...so does that mean you'll be wanting to sell the 3.4...hint hint>>?

 

[spf_lexus]

Very nice! Exhaust looks great! I noticed you've decreased the pulley size...so does that mean you'll be wanting to sell the 3.4...hint hint>>?

Thanks man. Im for the most part a broke college student so normally I am always interested in selling unused stuff for cash but I need to keep the 3.4". My rising rate fuel regulator failed so I had to swap back to my original pulley to keep from running lean.

 

[spf_lexus]

Finally got around to modifying the oil pressure sensor with a T section to house the sending unit. It fit within a cm in all directions. I used a small amount of teflon and everything is leak free. 25psi @ idle and 75psi @ freeway.




2 weeks back my carbon hood latch broke and damaged my OEM carbon hood. I got a deal on this one and plan to install pins this time. This is a seibon TS-II hood. 30lb lighter than oem. Im real busy this week so saturday I will be installing it.

 

[stevechumo]

You should install the hood pins to hold down the CF hood. There're several situations where the hoods flying off. If your hood is 1 piece from top to bottom and is very rigid with no flexing, then you probably don't need the hood pins. But if the top layer is glued to the bottom layer, then you need them for sure. Some CF hoods are better than the others, but don't take your chance.

I talked to a Seibon rep awhile ago and he also recommended the hood pins on his hood.

Another thing is if your engine bay is too hot, you'll need insulation under that hood. Otherwise, the heat will damage the hood.

 

[spf_lexus]

You should install the hood pins to hold down the CF hood. There're several situations where the hoods flying off. If your hood is 1 piece from top to bottom and is very rigid with no flexing, then you probably don't need the hood pins. But if the top layer is glued to the bottom layer, then you need them for sure. Some CF hoods are better than the others, but don't take your chance.

I talked to a Seibon rep awhile ago and he also recommended the hood pins on his hood.

I plan to install hood pins when I get back. My last Seibon hood was fairly rigid but what made me think twice was when im cruising at 80mph on the freeway and pass a semi truck, the hood will "bounce" up and down like a psycho trying to escape a stright jacket. 99% of all CF hoods are built like you said, fiberglass frame w/ carbon layer over the top. The safety catch is the real concern though IMO. My latch itself popped loose and the safety catch didnt do a thing. Just flew open and essentially grenaded the corners of the hood when it smacked the windshield. Very embarrasing when it happens in broad daylight Lol.

Another thing is if your engine bay is too hot, you'll need insulation under that hood. Otherwise, the heat will damage the hood.

I wanted to swap the fiberglass insulation layer underneath the OEM hood but Seibon does not provide a means to fasten it down. Frustrating. Anyway I think im safe with the heat department... remember my engine fire a few weeks back? Well that puppy melted wires + plug connectors and caught a rag that was under the hood on fire yet the hood itself never discolored or melted, per say. This event also happened w/ the hood closed, so much more heat than a standard boosted engine! I think now that I have sufficient venting, the chances of damage/discoloration should diminish.

Steve, did you manage to attach the stock insulation to your CF hood?

 

[stevechumo]

The safety latch on the CF hood is just to lock it, but not to secure it. If it popped and you're still ok, then you're very lucky. Should have bought a lotto right after that. LOL.

I sold the CF hood when it started to fade due to the heat, so I didn't put on any insulation. On my current hood, which is the OEM hood that has a cut for the hood scoop, I cut the insulation sheet to the shape of the hood & glued it. Ebay has those insulation sheets for around $50. Worked pretty good.

 

[spf_lexus]

The car wont see any freeway use until im back because im towing the SC behind a u-haul so i'll be safe until im back. Pins for sure though. Not skimping this time around. I am planning to order a bunch of thermotec heat insulation for my floorboards... ill have to see if they make an insulation layer as well. I have been told that Seibon is one of the few that actually uses a UV protectant on their products to eliminate the fading. I'll most likely add some form of heat blocking material.

 

[spf_lexus]

Here's a few shots of the new hood and my HVAC deletion/gauge install.

 

[stevechumo]

Is that the cop watching out for your car? LOL.

The Seibon hood fits really nice. It fits a lot better than the VIS that I had. I don't like the hood pins that much, but it's better safe than sorry.

Are you looking to drop that a little more? It looks somewhat high for a boosted ride.

 

[spf_lexus]

Is that the cop watching out for your car? LOL.

Yeah he sure was. I picked a quiet dead-end street along side I-25 and as soon as I jumped out to snap some shots this cop stops off the shoulder and starts asking me what i was doing. He thought my car was broken down. Lol. I dont know why I broken down car would stop angled in the middle of the orad w/ the owner snapping away pics but o well. He gave me a thumbs up and drove off. Just bad timing for a photo shoot!

[QUOTEThe Seibon hood fits really nice. It fits a lot better than the VIS that I had. I don't like the hood pins that much, but it's better safe than sorry.

Are you looking to drop that a little more? It looks somewhat high for a boosted ride. ][/QUOTE]

I get that a lot! The town I live in, Pueblo CO has some of the worst streets you'v ever seen. Every road has pot holes big enough to swallow a VW bug. The front/rear is actually level but i totally agree... it needs another 1/2" drop in front and 1/4" in the rear. When I get home in a few weeks its going to be dropped some more. I also have a slighty teisted front sub frame (salvage title here) and I can never seem to get the camber totally zero'd because 1 side is slightly bent. I will have a major decision when I get home../ replace the SC with another shell or swap sub frames and deal with the "bondo'd" rear fender myself.


As for Seibon, both hoods I have installed had flawless fitment. However I found it weird that Seibon uses 10mm bolts to fasten the hood versus the stock 12-or 14mm (forgot exact size) bolts. My guess is that they want some extra alignment room for the bolts?

 

[spf_lexus]

I know this may sound a bit "shady" but I promise it happened by accident!


My gauge cluster had burned out needles so I went to a salvage yard for a working unit. I installed it and everything lit up like it should... however the early SC has its odometer built into the cluster so I ended up trading my 210,000 mile odometer for one with 185,000 on it. Weird right? Anyway I doubt 25k will make much of a differece with this old of a car with a salvage title. I just found it weird how Lexus had build in security features but left the odometer so "old school". I remember years back when my neighbor cracked into his odometer in a MKIII supra to lower the mileage for a quick sale but I never expected lexus to follow suit.

 

[spf_lexus]

I know its been a while since I updated any real progress but I have been busy finishing my degree out in colorado. I just finished my last class and should be moved back to california in a few days. I have not forgotten about my 4.7L hybrid engine and my apaptronic ECU.


When im home I plan to install the 4.7L with the factory ECU and injectors (without the procharger) and break it in for about 1,000 miles. I have spent some time reviewing the install for this engine and plan to use my spare 1UZ loom for the standalone.


I have a small question regarding injector size:

My procaharger is producing about 9psi at sea level, and with a 4.7L block im expecting around 6-7psi? I can aqueeze maybe 2 more psi before the P1 besomes inefficient so 9psi will be my total target with the 4.7 block. Will a set of 440CC RX-7 injectors be sufficient with a standard 255lph walbro?

 

[stevechumo]

I boosted my car at 15 psi for standard driving with those RX7 injectors and a Walbro hp 255 lph. I even once boosted to 20 psi without any problem. Those injectors and the Walbro should be good for around 550 bhp. My fuel pressure was tuned at around 20-25 psi only. If I turn up the fuel pressure, I even can get a little more out of it. If I'd go back, I'll go with the Supra TT Denso fuel pump. I believe it pumps out 325 lph. It's also a high pressure pump.