Throttle Body Ground (by loudboxer)

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'02 Honda S2000
Grounding the throttle body isn't going to make 'more' power overall, but on some cars it seems to make a huge difference in how quickly you can get to what power's there. In my case, the change in low to mid-throttle, mid rpm driving is significant. Perhaps this changed the torque curves a bit through a more open throttle and more fuel earlier in the rev-range? I dunno. Fifth-gear passing on the freeway is now possible (from 60 to 80 is a snap), rather than having to drop a gear or two. Off-the-line acceleration is much brisker and driving casually around town is silky smooth. It feels like someone dropped a v-6 in my 3. I forgot I had the A/C on as well... My car must have been running like a pile of s*** before, never seeming at all happy below 3500-4000rpm. Anyway, I've had a huge smile on my face driving around since this mod.

I've been PM'd about photos, so here goes:

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The bits you need. 10gauge 1/4" ring terminals, and 10gauge wire. I just guessed at the amperage though, maybe bigger wire would be safer... After a two-hour commute the wire was barely warm. The throttle body is mounted to a plastic intake, so there's no grounding path other than a small wire in the harness I would suspect.


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The path. Pretty simple if you're not too anal about things. The battery-box cover has a slot on the side where the battery-bracket is bolted, just run the wire through there.


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The TB. Four 8mm bolts hold the throttle-body to the intake manifold. I used the upper-aft bolt, the lower aft would be more secretive though little harder to get to. Put the bolt back on tight, but don't strip the plastic of the manifold.


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The Battery Neg. Run the wire between the ECU box and the battery box, up and around where the bracket bolts. That's a 10mm nut on the battery post. Get it all snug when done.

Enjoy the friskiness.
 
What's with you making all sorts of nice writeups :D

I might try this on my Protege out of boredom, I'll post if it makes a difference or not.
 
interesting, i may have to re-arrange my 1sty grounding kit a bit, IF this does indeed result in a change. subbin'...
 
MSP#735 said:
interesting, i may have to re-arrange my 1sty grounding kit a bit, IF this does indeed result in a change. subbin'...

I'll definitely give it a try this weekend if I can find a store that carries nice wire to use for the job.
 
would i get the same effect if i grounded it to the chasis where the neg battery lead goes? i would think so but i have a nice enough looking neg terminal and no more room for wires that big....
 
i didn't write this and i was surprised it hasn't been posted before in the how-to so i posted it. Most 3 (and 6) owners who have done it report differences, and the ones that have the most pronounce effect are from the ATX crowd.

For the TBs that are cable-driven, this won't do anything in throttle response, but you get a better ground to your TB tho.
 
Yeah its definitely noticable in my ATX 3 it doesnt really help power wise but is definitely more responsive.
 
thebeansoldier said:
i didn't write this and i was surprised it hasn't been posted before in the how-to so i posted it. Most 3 (and 6) owners who have done it report differences, and the ones that have the most pronounce effect are from the ATX crowd.

For the TBs that are cable-driven, this won't do anything in throttle response, but you get a better ground to your TB tho.

yeah... proteges and non-US 3s & 6s have cable throttles anyway
 
Ok I lied, I didn't try it this weekend. I forgot that the 3 had an electronic throttle, so this wouldn't really do anything for the Protege.

I did check on partsexpress.com for pricing for all the 4 gauge cable and connectors I need to make myself a grounding kit though. It should be fun :)
 
this only works for cars that use the "Drive-By-Wire" system. i did this for a couple of mustang and f-150 owners cars.
 
Mileage Impact?

Have you noticed any mileage impact from this? More, less, or the same?

Thanks for a nice writeup.
 
CajunGreek said:
Have you noticed any mileage impact from this? More, less, or the same?

Thanks for a nice writeup.

All it does is decrease the throttle tip-in delay, provide a more linear acceleration give you smoother shifts. ATX owners report the most "gains".
 
Cool, thanks for the pics. Does anyone have the torque specs of the throttle body screw? I know I would likely strip the plastic of the manifold or not tighten it enough.

BTW, anyone actually notice an improvement with the intermittent rough idle or A/C?
 
blondee_yvr said:
Cool, thanks for the pics. Does anyone have the torque specs of the throttle body screw? I know I would likely strip the plastic of the manifold or not tighten it enough.

BTW, anyone actually notice an improvement with the intermittent rough idle or A/C?

TB torque spec is 6-8ft/lb. Members have reported better idle and smoother acceleration. Not sure about the A/C.
 
So this does nothing for the Protege?? I did this mod to my Protege and I noticed some difference, What could it be then, since it is just a Cable throttle?

There is a distinct difference!
 
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thebeansoldier said:
TB torque spec is 6-8ft/lb. Members have reported better idle and smoother acceleration. Not sure about the A/C.

Thanks!

I am sure it wouldnt hurt the A/C. Damn, I thought I had a torque wrench, I think someone borrowed it and never returned it. (glare)
 
I tried this mod (2006 Mazda 3) and it did nothing at all! Before I started, I got out my DVM and measured the resistance from the TB to the cars neg. battery terminal (open circuit). So the TB is completely isolated from the ground of the car. With this isolation in mind I had my doubts, but decided to give it a go anyhow - what a waste of time. Can anyone give me a valid reason why this would do anything to the throttle response? Thanks
 
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