Giant loss of low end...possible causes??

[Muzzy]

1. no EGR?
2. polished head?
3. no butterflys in intake mani??
4. no cat?

would any of those cause this???
i think its the butterflys and head...wut do u think??

[muskrat]

It's #3.

JUst this weekend I put an Injen air intake on my '92 240, I drove it to work and back monday and by freeing up the air intake that much I lost TONS of low end power, so monday night I took it off and put all the stock junk back on and I'm very happy. Will be even happier if I can sell this intake for some cash!

[LanceS13]

#1. Not likely.
#2,3, and 4 can all effect the placement of the torque peak in the power band.

[wherezmytofu]

did u check if the maf is on correcly?

[wherezmytofu]

did u check if the mafs is on correctly?

[Muzzy]

yea it fine..its been this way since i rebuilt the engine and did all that stuff

it pulls hard after 3200rpm

[uiuc240]

Originally posted by muskrat
It's #3.

JUst this weekend I put an Injen air intake on my '92 240, I drove it to work and back monday and by freeing up the air intake that much I lost TONS of low end power, so monday night I took it off and put all the stock junk back on and I'm very happy. Will be even happier if I can sell this intake for some cash!

Did you reset the ECU? If not, the ECU was most likely freaking out due to the recent addition of air to the system. You need to reset it, or allow time for it to calibrate. Don't sell your intake before you try it for at least a few days. I guarantee you're not reaping the full benefits of it yet.

Eric

[Dream240]

Originally posted by uiuc240
Did you reset the ECU? If not, the ECU was most likely freaking out due to the recent addition of air to the system. You need to reset it, or allow time for it to calibrate. Don't sell your intake before you try it for at least a few days. I guarantee you're not reaping the full benefits of it yet.

Eric

Yeah what he said.
The ECU is a pretty smart little gadget. I recently moved to 4200 altitude area from Southern Cali and it took about a week for my car to perform back to normal. The start ups were sluggish and the acceleration was very weak. Now it's still a little weaker than before but I assumed that it's because the air here is thinner. Whatever you do, don't sell the intake just yet. Put it back on and give the car about 300-500 miles to adjust. The injen intake really produces good overall power from your stock setup when compared to the stock airbox. And it has that really cool rumble when you punch it.

[Muzzy]

well can i take the upper half of any KA intake mani (91-98) and put it on my 91 KA or just 91-94?

[muskrat]

Originally posted by uiuc240
Did you reset the ECU? If not, the ECU was most likely freaking out due to the recent addition of air to the system. You need to reset it, or allow time for it to calibrate. Don't sell your intake before you try it for at least a few days. I guarantee you're not reaping the full benefits of it yet.

I did not reset the ECU, wish y'all had told me that when I asked about it the day it was in, the only reply I got here was "Yes, it will bog down."

I am very happy with the low end acceleration on the car, if I am going to lose any of it putting the Injen back on then I don't want it. My car is not a race car, just a street car, so all I care about if 0-60, and maybe even more 0-35.

If I was to reset the ECU with the Injen installed would my torque improve? I heard a bigger air intake just helps the top end.

[uiuc240]

Torque (or low-end grunt) is affected by two things on the intake side:

1. Length of tubing (longer makes more bottom end, shorter makes more top end).
2. Diameter of tubing (larger diameter lowers air velocity, which allows it to breaths better up top...smaller diameter fills up with air faster, and makes good power down low).

All upgraded intakes with larger piping will lose a LITTLE bit of low-end torque, but the affects are minimal. After a couple days of driving, you'll stop even noticing it. Oh, and the ECU *does* have a big effect on it.

Eric

[deviousKA]

your problem is the removal of the secondary butterflies, i cant believe it even idles or drives at low rpms with them out. i was debating whether or not to remove them earlier on. search, i have a post on it

[Muzzy]

yea it still runs fine.
240sx.org said it freed p HP but had a ruff idle but said nothing about loss of low end

[deviousKA]

Read the post Removing secondary butterflys (http://www.zilvia.net/f/showthread.php?s=&threadid=32609) you even replied. the butterflies help swirl the air/fuel increasing low end torque. what do you mean polished your head? the ports? did you polish your intake side? that could also be part of the problem, if your going to polish or port, the intake side is not the one to do. still i am unclear as to whether you have ka24e or de

[Muzzy]

DE and yea i polished the intake side too

[Titan]

Originally posted by Muzzy
DE and yea i polished the intake side too

Why? You're supposed to leave the intake side rough to the touch. This allows air turbulance and mixes the air with the fuel better. If you polished it, you're going to have fuel separation issues.