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TB mod downsides?

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Old 05-07-02, 12:31 AM
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what 7

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Question TB mod downsides?

Hey guys, what are the TB mod downsides? I'm going to do this soon, and I want to know if there is a reason why I shouldn't.
Old 05-07-02, 12:51 AM
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low end power loos
Old 05-07-02, 03:47 AM
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Originally posted by DCmina
low end power loos
^There is no truth to this.

Downsides: Cold start is affected; idle may not stabalize until engine is warm.
In very cold climates, engine may not idle at all until warm.
There is no change to low end power, only an increase in top end power and smoothness, a tad bit better thriottle response, and a tad bit better boost response. Last two are more noticable with TB porting.
Old 05-07-02, 07:25 AM
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Con: No cold start fast idle cam.
Pro: The opportunity to remove the coolant line that starts under the upper intake. It blew out and stranded me once , so it’s now capped off..
Old 05-07-02, 08:50 AM
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sorry, that's what I read in the forums

I did a search, and this is what I found:
https://www.rx7club.com/forum/showth...&highlight=mod

https://www.rx7club.com/forum/showth...&highlight=mod

https://www.rx7club.com/forum/showth...&highlight=mod
Old 05-07-02, 10:38 AM
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i agree with scathcart, it's a good mod just be careful with the throtle cables if you shorted or lengthen them it's hard to get back to perfect. but i'd recomend it it was at least fun and interesting if not frustrating (note: the tb mod was not what was frustrating me)

james
Old 05-07-02, 01:10 PM
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i did the tb mod and i still gots to 3 when i start it up in the morning did i miss out on taking something out
Old 05-07-02, 03:01 PM
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the 3k rpm start-up is not related to the throttle body. its controled by a small wire on the bottom of the radiator. there is a plug on the bottom drivers side of the radiator with 2 wires coming out of it. one of those wires controls 3k rpm start. you pull one of em out to diable it.
Old 05-07-02, 04:49 PM
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I have a 91 TII and there is nothing on the bottom of the radatior. Where is that. How does it jack up the RPM like that if it dosn't have any control on the throttle cable?

James
Old 05-07-02, 04:56 PM
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Any link on how to TB mod?
Old 05-07-02, 05:22 PM
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Originally posted by KNONFS
Any link on how to TB mod?
http://fc3s-pro.com/TECH/HOWTO/TBM/tbm.html
Old 05-07-02, 05:35 PM
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Originally posted by Wankel7
I have a 91 TII and there is nothing on the bottom of the radatior. Where is that. How does it jack up the RPM like that if it dosn't have any control on the throttle cable?

James
You don't have one. Try starting the car in gear. Maybe remove the AWS? Dunno on the last one...
Old 05-07-02, 05:40 PM
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Originally posted by DCmina
sorry, that's what I read in the forums

I did a search, and this is what I found:
https://www.rx7club.com/forum/showth...&highlight=mod

https://www.rx7club.com/forum/showth...&highlight=mod

https://www.rx7club.com/forum/showth...&highlight=mod
Even in your links I couldn't find anyone discussing a low end power loss. Ted was talking about creating a bit of a hesitation or bog if you mash the throttle to WOT at low rpms, no power loss.
Old 05-07-02, 06:48 PM
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I have also never experienced any low end power loss with this mod. It works really well and the response is better. The best thing is that I have just recentley did a before and after test using my Power FC and Intake air temp. dropped about 7-8 deg. after doing this mod.

I see no real drawbacks to doing this.
Old 05-07-02, 07:45 PM
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I've been contemplating this mod also.

Since i live in MN (where it's cold 5/12ths of the year) i really need a steady idle for warming up the cold mornings....

anyone else in a similar situation?

Also, how much coolant goes through the intake? could this possibly effect cooling?
Old 05-07-02, 08:05 PM
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Hmm, I'm pretty sure I read that before. Not in the links I posted, but I read it here.
Old 05-07-02, 10:03 PM
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You’re only removing a restriction in the throttle body, so there’s no reason why that would cause a loss of power anywhere. Part of the job of those dampened throttles is to stop the secondary ports getting a sudden whack of air when the accelerator is pushed down sharply. As Ted has said, that would cause stumbling at lower rpm due to suddenly incorrect mixtures before the ECU caught up.
Old 05-07-02, 11:45 PM
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Just do it and be happy. I did it and I am. It doesn't get too cold here in Seattle but I try to let it warm up for a few minutes anyway before I take off. The response is all worth it.

jerk_racer@hotmail.com
Old 05-08-02, 11:27 AM
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i moded and ported my tb took the better part of a day and i have had no problems no low end power loss nothing, just much better responce.
Old 05-08-02, 11:45 PM
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If you want to only remove the secondary throttle plates, and NOT remove the coolant line (because of cold climate conditions) then you don't really need to remove the throttle body from the engine do you? You just open it up, remove the plates and the bar and plug the hole?
Should I remove the dashpot too? It won't be doing anythign anyways right?

Thanks,
Nima
Old 05-09-02, 07:59 AM
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Those secondary throttle plates are controled by a device that has the coolant flowing through it. If you take the plates out of there and leave the thermowax there with coolant running through it you have only achived half of the advantage of this modification. The other half is not having this coolant line under the manifold. Not having this line there makes taking that manifold easy to get off.

When I was thinking about doing the mod (For months and months) I was big wuss. So finally, I said the hell with it. I did it. So just do it

James
Old 05-09-02, 07:59 AM
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Oh yeah. The dashpot. From what I see you need that thing so the throttle plates dont slam shut.

James
Old 05-09-02, 10:42 AM
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you only need the dash pot at the back of the tb go to ted's site fc3s-pro.com and look it up it is rather easy. and forgot to mention i did get that anoying hesitation wot condition but i'm under taking action to remedy this crap.

james
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