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Old 11-02-2003, 11:11 PM   #1
3BadHabbits
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Question Grounding Mod questions

I have that hesitation(flat spot)!!! It drives me nuts. Now Ive read about the grounding mod, but doesnt some company make one? I think HKS right? Anyway if I cant get on from them can I use like 12-8 gauge wire that we use for our amps?
Thanks Nick
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Old 11-02-2003, 11:20 PM   #2
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It's much cheaper to do it yourself.
I did it with 15' of 8 gauge power wire from an audio shop and bought some gold ring connectors.
Speaking from my experience.. the mod will solve some of the hesitation but it will probably come back.
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Old 11-02-2003, 11:33 PM   #3
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Quote:
Originally posted by Zen
It's much cheaper to do it yourself.
I did it with 15' of 8 gauge power wire from an audio shop and bought some gold ring connectors.
Speaking from my experience.. the mod will solve some of the hesitation but it will probably come back.
It's a remedy but not the cure. I did the ground mod mostly for looks, and it did help but I still have a torque valley midrange in my revs. I believe it's due to the design of the intake manifold.
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Old 11-02-2003, 11:33 PM   #4
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Quote:
I believe it's due to the design of the intake manifold.
Is the 02 and up RS manifolds different?
"the manifold"
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Old 11-03-2003, 12:50 AM   #5
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If you don't plan to do it yourself, then here's a good deal-
http://cgi.ebay.com/ebaymotors/ws/eB...tem=2440776271
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Old 11-03-2003, 01:14 AM   #6
3BadHabbits
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Wondering if the plastic intake manifold is better??
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Old 11-03-2003, 10:51 AM   #7
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or this nice one is actualy for the 2.5 and cheap too. here on ebay
Shane
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Old 11-03-2003, 01:53 PM   #8
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PARANOID56

do you think that kit will work on a 2.2? if so i think ill pick one up.

-mike
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Old 11-03-2003, 03:57 PM   #9
chris124816
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yea it will fit the 2.2
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Old 11-03-2003, 04:07 PM   #10
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Anyone have the flat spot with a 2002 and up?
Wondering if the plastic manifold is better..
Nick
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Old 11-03-2003, 06:25 PM   #11
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I have an 02, and I don't notice any flat spot. Maybe I just don't know what to look for though... is it bad enough I'd notice? It didn't pull very well on the top end stock, but intake and exhaust fixed that. I did the grounding mod and didn't notice any difference.
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Old 11-03-2003, 06:51 PM   #12
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There is a noticable flat spot...3-5K when 5k comes it feels like your flipping a tiny vtec switch
Nick
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Old 11-03-2003, 06:51 PM   #13
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on mine, i noticed that the little hesatation when you first give it a lot of gas was gone. and my head lights were a hair brigher. but that was it.
As for my kit, it should work fine, i have put it on 2.2s before and it was mostly streight forward. if you do have any questions just email me.
Thanks
Shane
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Old 11-04-2003, 12:49 AM   #14
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Quote:
Originally posted by 3BadHabbits
Wondering if the plastic intake manifold is better??
The plastic manifolds and the cast aluminum ones are exactly the same except for the mount for the MAP sensor and other little crap.

It's the design that sucks. I believe it has to do with the runner length or shape that causes some kind of harmonic feedback at that specific rev range leading to a sudden loss of power. IE: air is constantly flowing to the engine but is bounced back, when it reaches a closed intake valve, and then travels back to the cylinder when the valves open. Managing these pulses is key to determining the torque/power band of the engine.

(Someone correct me if I'm wrong cause I'm just winging it here.)
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Old 11-04-2003, 01:03 AM   #15
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i recall hearing something dealing with the electrical interference in the intake manifold screwing with the map sensor or something, in which case the plastic manifold would eliminate that problem, but i don't really notice any hesitation with the plastic intake, but maybe its just me
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Old 11-04-2003, 01:05 AM   #16
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This is SO super easy to do, and I'd say defintaly do it yourself (no kit). I spent like $20 total (did get a REALLY good deal on some hefty gold plated connectors though). It helped a little, but then it kinda came back...I don't know. I like it mostly for looks also!
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Old 11-04-2003, 12:24 PM   #17
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ok, nobody is asking the real question. If the grounding mod is fixing the problem why is it coming back? and since just grounding the car better makes the problem go away then why isn't that the problem??

-jeff
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Old 11-04-2003, 12:47 PM   #18
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I think it has something to do with the knock sensor. It has been discussed before.
Has anyone gotten hesitation with no mods?
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Old 11-04-2003, 01:16 PM   #19
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Quote:
Originally posted by Zen

Has anyone gotten hesitation with no mods?
yeah me, before I did the grounding mod

I think your right, about the knock sensor, I wonder if we have something like this ( http://forums.nasioc.com/forums/show...hreadid=302047 ) that'll work on our cars, for the hesitation.

-jeff
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Old 11-04-2003, 02:18 PM   #20
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Quote:
Originally posted by obyone

It's the design that sucks. I believe it has to do with the runner length or shape that causes some kind of harmonic feedback at that specific rev range leading to a sudden loss of power. IE: air is constantly flowing to the engine but is bounced back, when it reaches a closed intake valve, and then travels back to the cylinder when the valves open. Managing these pulses is key to determining the torque/power band of the engine.
I keep seeing the "hesitation" topic come up all the time, and I've been thinking that both the ECU (grounding mod) and the manifold design, as described by obyone, are to blame for the deadband. I personally get the little "VVT-like-switch" effect at about 3000 RPM or just a hair over, and I have no engine mods. And other folks say they get it at 4k or above. But we can all agree that we get it somewhere. The grounding mod seems to have some benefits for most people, but the hesitation always comes back. So I think it's a little bit of both. Here's my reasoning:

If everybody experiences the "hesitation" problem, then fundamentally there is some minor design flaw, possibly hardware related. Many people are able to temporarily remedy the hesitation by an electrical change, changing the way the ECU views and operates with respect to the "perceived problem." The ECU itself is constantly learning and watching how you drive and attempts to correct what you have corrected so as to operate in the factory defined parameters, which would explain why the problem always comes back. Back to the hardware issue, harmonic wave fronts are known to adversely affect manifold runner flow. I won't get deep into this subject, but suffice it to say that like obyone described, the sound wave fronts actually reverberate inside the runners and slow the air flow at certian notes, or as we know them, engine speeds.

(Also just winging it here)
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Old 11-04-2003, 04:57 PM   #21
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If its coming back then its just more than a electrical problem. Something has to be sending the air "backwards". My car (right now) is all stock. I step on the gas and there is power to 3k, flat spot from there to @4500-5K and then the "vtec kicks in" back to its normal power band. I wonder if porting would help or honing?
Nick
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Old 11-04-2003, 05:16 PM   #22
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Since the ECU goes into closed loop mode at WOT, would it not make sense that flooring it at low rpm simply makes it run too rich? I know when I pass people and I don't downshift, I take off faster if I roll into the gas instead of flooring it.

Yeah my car is slow at low RPM, but, duh... most cars are...
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Old 11-05-2003, 04:10 PM   #23
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One suggestion for grounding mods- the expensive kits you speak of SHOULD be made of a 4 guage, not 8, and the connections are gold plated AND soldered providing better/faster current transfer. I plan to spend the extra $ for a better kit b/c I've heard pple using this one (kastleskorner.com sells it) say it was a good improvement in overall drivability and the way the engine ran cold or hot. You're also not going to notice a change in "hesitation" if your intake/exhaust system is still stock.

If desired, you may try reseting the ECU once the grounding is done- I did this with my intake (no ground mod, yet) and noticed a sizeable difference in power and throttle response. Your ECU is set at the factory and is "supposed" to learn as you drive but you have to realize it is set for the stock intake and exhaust. I say every time you do a power mod, it is good to reset the ECU so it can start learning the correct MAPS to match your engine's now modified way of breathing.
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Old 11-05-2003, 05:50 PM   #24
PARANOID56
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Ok, let me but in here a little. 4ga wire is way overkill. The voltages we are dealing with here are so small that even 10ga is overdoing it. I will agree with soldering the ring terminals, this will help a lot, as long as the soldering joint is done correctly. I however have not seen another kit out there that solders there joints, especially 4ga kits, as that is some huge wire to be soldering correctly. I tried to look at that site but it appears to be a bad link.
As for ring terminals if you want the lowest resistance get solid silver terminals, as these have the best conductivity. (they use gold as it has a better resistance to corrosion) The people that go with 4ga wire usually just do it for the looks. Gust go down to your local stereo shop, get some good 8ga wire, some nice gold ends, and silver solder and have at it. Make sure you shrink wrap the ends too. You will save your self the most money that way. As 98% of all grounding kits out there are universal kits and are made to fit a lot of engines, so your kit most likely wont be any worse then there’s, but a whole lot cheaper
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Old 11-06-2003, 11:02 PM   #25
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I guess going with 2 gauge was WAY over kill then

I just kept thinking about the power being produced by my altenator, I wanted a good balance
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