InternetRoadkill

Has anyone done an experiment to see just how bad the filter airbox hurts acceleration? We all know that the opening to the outside world is too small, but I'm curious just how bad it hurts performance.

My 4R has the 285 LC engineering cam and headers and starts out fine, but quickly runs out of breath above 3000rpm or so. I'm guessing the airbox is responsible. Thoughts?

lotalucas

I started building a cold air intake for my truck. I don't have the headers or cam but it sucks air pretty hard. I have a really flexible air hose going to my air box right now and when i rev it there's enough suction to compress the hose. I think once i finish this intake it should help alot. I wish there was some way to bypass the butterfly valve though. I think that seems to have a lot to do with slowing down how fast the air goes in.

InternetRoadkill

I got time to kill this afternoon. I'm going to pull the headlight off which will allow more air into the airbox. I'll do some 0-60 times with and without the headlight & bucket installed. Stay tuned.

Team420

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Flash319

You should just do some calculations and figure out what the engine requires for air at different RPM's. Then calculate how much air you can pull through the size of the opening. I think you will find that there is not that much restriction, if any. The hard breathing you are feeling probebly has more to do with cam profile and valve size (number of valves per cylinder) then anything else.

Yota82

What is the ignition timing set at?

norcalsvx

i run a 261c cam lce header/downey intake it pulls better with the intake over my old set up (stock box w/ k&n) it help more for me with some AFM tunning (i went 2 clicks richer)

i would like to build a alum box for the filter (for a lil more cooler air) and maybe a duct instead of my corner light.


afm mod info here

http://www.4x4wire.com/toyota/minutemods/afm/

InternetRoadkill

Well, I'm surprised and a little disappointed. I made 3 runs each with and without the headlight installed. The 0-60 times didn't change much, if at all, so it looks like the headlight breather is not a significant impairment to performance.

All of the runs, except one, produced a 0-60 time of around 26 or 27 seconds. (Be still my heart.) I had one run of 21 seconds, but I think I had some help from a favorable wind on that one (the wind is blowing 25 today).

Maybe someone could try the same experiment and post some results as a comparison. You'll need to pop the grill on the left side to remove the headlight and bucket, but it's easy to do and takes just a few minutes.

My config:
88 4R, 22RE, auto (340H), A/C on,
LC Engineering headers and cat,
LC Engineering 285 cam,
Magnaflow 40 muffer, 2.25 pipes,
stock timing and AFM settings.

Robert m

iTrader: (2)

if its taking you 26 seconds to reach 60 mph, then you have much bigger problems then just a restricted air box.

Junkers88

indeed.

norcalsvx

its the auto that is killing ya , and what size tires?

abecedarian

at what rpm are the shifts occuring?

InternetRoadkill

The 4R is using the factory tire size. The auto is wanting to shift around 4700 rpm. I did notice that it's reluctant to upshift. I also noticed that there is a pretty good step between 1st and 2nd. I'm used to my MR2 which has a close ratio 5 speed, so I may be expecting the 4R to shift the same.

Anyone with a 22RE auto care to post their 0-60 times? The truck is making 19mpg which is not bad for an auto with the a/c running.

InternetRoadkill

Hmmm, it's hard to find reviews of a truck that's 20 years old, but I did find one. It didn't have a 0-60 time, but it did have a quarter mile time of 20.7 at 67mph, so this places the 0-60 time at a little less than 20 seconds. The time estimators based on horsepower and weight say around 18 seconds to a rather speedy 14 seconds (not likely). So it seems clear the 22RE is not making its full rated horsepower.

Looks like I get to poke around the fuel injection and see if I can find the problem. This should be fun since it's not throwing any codes. Oh boy! A mystery to be solved.

CJM

20+ seconds 0-60??? Thats insane, you have way larger issues.

myyota

Start with the simple stuff first, plugs, plug wires, cap, rotor, and most important the fuel filter, then see if thats makes a difference.

thook

What are the valves set at, and when was the last time you adjusted them?

norcalsvx

i really cant see a auto 22re going very fast

corax

hook a vacuum gauge up to the engine and see if the exhaust is restricted. How many miles on the 4runner?

InternetRoadkill

Based on some number crunching, it's acting like 2 of the injectors are not firing which suggests a problem with the ECU. I'm going to pull the plugs to see if there are a pair of 'dry' cylinders.

The engine is essentially new with 600 miles on it.