agiagi

Hi. I have looked at several options for replacing/modifying the stock airbox on my SC400 ('92) and used my old hotrod eye to deal with restrictions inherent in the original design. The air-box snorkel uder the pass. side headlight was cut back a bit and serated. then, the forward upper-right side of the filter retainer/housing forward component was augered w/ 4 overlapping 1" circular openings to provide for more air-flow while being positioned awayf rom the engine compartment heat. Of couse, a K&N filter is inside the housing.

FYI

Mike Torst
'92 SC400 modified...

Lex Luthor

results.....

agiagi

Engine pulls stronger at high rpm, similar to having the filter retainer removed from the airbox. Still quiet too.

Mike
'92 SC400 modified

bolts_cj77

go to

http://www.users.bigpond.com/pgscott

and follow the links to the BFIhttp://www.users.bigpond.com/pgscott

Peter has done all sorts of testing with different airbox mods.

SCV8

I was surprised at how close that snorkle was mounted to the bumper structure up in there.I trimmed that on my car,and noticed a big difference as well.After the addition of an aftermarket ecu with bumped up timing,accelerator pump shot effect,I removed even more of the airbox,but most of the improvement had been at the first go around,since the restriction is in the airflow meter,and the big hole just bombards the a/f meter momentarily,then is very similar to what it would be through the cut-back snorkle,once a steady flow is established through either one.
Another thing you can do is to radius the surfaces opposing the airflow on the entrance of the a/f meter, just be sure and radius the portion between the bypass passage and the main passage,starting at the bypass opening.If you just file the thing into a blade from both sides,the bypass will flow more and mess up your idle mixture as a result.

agiagi

Humm, sounds like another DIY project for next weekend. Thanks!

Mike
'92 SC400 modified

007lexus

hey agiagi,

just curious what mods have you done to your SC400?

007

agiagi

Hi. regarding mods - G-Force ECU modification, airbox opened (as above), K&N, High flow- common chamber cat, 2.25 true dual exhaust, Dynaflows, 160 degree thermostat, steel high-density fin-count radiator, Drilled/slotted rotors, new drivetrain (tranny, driveshaft, rear end, half shafts, bearings etal), Iridium plugs, late series front clip, usual new parts (water pump, power steering, timing belt, etc). Nothing really bigtime, like a blower....

Mike
'92 SC400 modified

ChrisK

iTrader: (1)

agiagi,

Where did you get 160 degree thermostat?

Thanks,

agiagi

The 160 degree thermostat is TRD 16340-SP030
90916-03100 71'C, 160'F

as to mods for sc300, I do not know if the airbox is the same, but the idea is to suppliment the airbox with additional cool airflow - My additional opening measures 4 inches by 1 inch, upper-right side forward airbox shell.

Mike
'92 sc400 modified.

933005spd

Why don't you remove the entire assembly and replace with a conical filter? The stock box is definatly a bottleneck same type on both 300 & 400.

Peter

Lex Luthor

You know, I tried removing my intake snorkel, top end power definitely picked up, but I got a bad low end bog that was unbearable. I can only attribute this to turbulence introduced before the airflow meter, but others have had a similar experience. I put the snorkel back in, problem solved. Peter Scott's data on the intake is very valuable, I wouldn't proced with any cutting before reading it. Did trimming the snorkel increase power for you without introducing a bog? If so, please explain exactly what you did, if ya got a pic it would be bueno.
Thx,
- Jon

Keith13b

iTrader: (3)

LEx,

I have removed my snorkel about a week ago. I HEAR a bog sound, but I don't 'feel' the bog. The bog I hear is just noise coming from the intake. Do you actually feel a bog? Removing my snorkel made a huge improvement. I hear people talking about this bog, but to me at least, its just a noisier intake.

Just my .02 cents.....


Keith

Lex Luthor

Sup, Keith-man. I have a pretty sensitive butt-dyno, and yeah, I could feel a bog. At first I thought the same thing, I was just hearing it (and it did make a hellofa low-frequency drone as it sucked air), but it definitely bogged. I would give a good amount of gas from a stop, and the car would bog, I would move the gas pedal down another 20% as it was bogging, and it would make absolutely no difference, as if I had never given it more throttle, it was very upsetting. I was worried it was something else, since I couldn't believe it could just bog out like that from the stupid schnazola, but sure enough, I put the schnoz back in, and the problem was solved. I have to admit, though, top end power was definitely improved, third and fourth gear pulled harder for sure, especially flooring it from a roll, when it kicks down into a lower gear, it ran nice, but the bog was unbearable. Anyone else that's had the same thing happen? Keith, are you sure it runs the same or better in first and second gear?
- JonJon

Keith13b

iTrader: (3)

I drive pertty slow most of the time, and the rest of the time, its to the floor. My question is : does it bog between certain rpm's (I never really paid attention). Remember I have a 3500 stall TC. So when I hammer it, I'm immediately up there in the rpm's. So I'm thinking that I'm just running thu the bog before the TC locks up. I don't notice the bog at low or moderate throttle, it's only 3/4 throttle that I hear it (I love the intake sound now BTW). But I don't hear it at all when I punch it. I guess I just have to go out to the car and run it hard on the drive home today to do some Research.

I'll post my results tomorrow

I'm outa here to waste some gas - Later


Keith