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Throttle body mod. ?

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Old Feb 26, 2006 | 09:46 PM
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Throttle body mod. ?

Ok i search could not find. I did the tb mod on my 87 TII. I left the thermowax. Well anyway my ? is what do you do with the vacuum hose that comes from the water thermo valve and goes to the round thing on the other side of the TB , don't know what its called. Its round and has a rod coming out of it that's conneceted to the throttle plate shaft arm assembly. Do i just cap it off, if so where at the uim where it feeds the water thermo valve and eliminate the thermo valve completely, or cap it where it come's out of the valve. Thanks Tony
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Old Feb 27, 2006 | 10:08 AM
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It's the secondary double throttle.
On an NA its job is to keep you from WOT on a cold motor.
On a TII it also slows the opening of the secondary ports.
If you remove it's vacuum control, you can either wire the double throttle open, or remove it entirely.
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Old Feb 27, 2006 | 10:16 AM
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remove it!

this is how mine have turned out. ive done three so far, and you get faster and better at doing them with time.

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Old Feb 27, 2006 | 10:19 AM
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How mutch does the TB mod help? Is it hard? i have removed all the parts i dont need but i havent modded it with my dremel yet.. (dont want to damage it).
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Old Feb 27, 2006 | 10:24 AM
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eh. just sorta have to do it. its time consuming to get it to be polished on the inside again, but i dont have ideal tools.
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Old Feb 27, 2006 | 10:30 AM
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mine was knife edge ported.
Attached Thumbnails Throttle body mod. ?-portedtb.jpg  
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Old Feb 27, 2006 | 11:08 AM
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water thermo valve. what do i do with that. ive already removed the double throttle i need to know if i can eliminate the water thermo valve completely. Thanks
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Old Feb 27, 2006 | 11:37 AM
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i removed it.. and the car runs..i just followed this writeup http://www.rotaryresurrection.com/ro...emisremov.html
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Old Feb 27, 2006 | 12:25 PM
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The porting is a waste of time IMO.

I don't think you'll notice a difference unless your going all out 500hp.
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Old Feb 27, 2006 | 01:45 PM
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Originally Posted by Digi7ech
The porting is a waste of time IMO.

I don't think you'll notice a difference unless your going all out 500hp.


I am
but I am thinking that I might build a custom upper intake manifold and run a huge mustang TB. Even ported this TB is very small. Once you go standalone you can run any setup you can think up.
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Old Feb 27, 2006 | 02:26 PM
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^true. I bet even using a RE or REW TB would help since they're a bit bigger.
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Old Feb 27, 2006 | 03:27 PM
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yes they are bigger but not anywhere near 90mm from a FAST unit.

http://www.jegs.com/webapp/wcs/store...0703&langId=-1
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Old Feb 27, 2006 | 03:43 PM
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Well......
I guess that would work....

lol. That's gotta be a crazy manifold your making
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Old Feb 27, 2006 | 11:14 PM
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Originally Posted by my-sons RX-7
water thermo valve. what do i do with that. ive already removed the double throttle i need to know if i can eliminate the water thermo valve completely.
If the thermovalve just unscrews from the thermowax then you could remove it and plug the hole with a threaded bung. Easiest would be to just leave it there and remove all the vac lines. Cap the vac nipple at the UIM.

Originally Posted by Digi7ech
The porting is a waste of time IMO.
I wouldn't call it a waste of time but I would call it a waste of money. It's the sort of thing that's worth doing yourself but definitely not worth paying someone else to do.

In my case the UIM and TB were off the car for vac rack removal and the die grinder was out for another job. What else was I going to do?

Polishing the inside of the TB, now that's a waste of time...
Attached Thumbnails Throttle body mod. ?-dsc00824.jpg   Throttle body mod. ?-dsc00826.jpg  

Last edited by NZConvertible; Feb 27, 2006 at 11:16 PM.
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Old Feb 28, 2006 | 04:51 AM
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NZConvertible I knew you would come through, there where gitting of my subject. BTW do you know the plug size in case i want to remove it. Thanks Tony
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Old Feb 28, 2006 | 05:50 AM
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No idea sorry, J-spec engines don't have them
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Old Feb 28, 2006 | 06:24 AM
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http://fc3spro.com/TECH/HOWTO/TBM/tbm.html

theres the write up for it.Its very good and detailed.

jake-
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Old Feb 28, 2006 | 10:51 AM
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Originally Posted by mazda se
http://fc3spro.com/TECH/HOWTO/TBM/tbm.html

theres the write up for it.Its very good and detailed.

jake-
I did their mod. but thay don't say anything about the water thermo valve. thank for the help anyway. Tony
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Old Mar 1, 2006 | 12:44 PM
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Originally Posted by my-sons rx7
I did their mod. but thay don't say anything about the water thermo valve. thank for the help anyway. Tony
2-5th picture show the removal of the thermowax/coolant assembly.

You remove it then remove the linkage for it. You then remove the secondary butterflies and cap the hole it creates.
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Old Mar 1, 2006 | 03:56 PM
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Originally Posted by Digi7ech
2-5th picture show the removal of the thermowax/coolant assembly.

You remove it then remove the linkage for it. You then remove the secondary butterflies and cap the hole it creates.
Im not talking about the theromwax. Im talking about the water thermo vavle it has two vacuum lines on it. i keeping the thermowax. I removed the secondary linkage and butterflies.
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Old Mar 2, 2006 | 05:55 AM
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PLug it off or use it for an aftermarket boost gauge!!!
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Old Mar 4, 2006 | 12:43 PM
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Can someone tell me the effect of doing the TB porting mod? HP gain, respons ?
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Old Mar 4, 2006 | 12:53 PM
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I don't think it's about HP gain. More about flow characteristics. Without the big secondary flapper+rod in the way, there is tons more potential for flow. And when knife egded, the air is directed right thru the TB, rather then being shifted around, creating turbulence, like stock.

HP, I'd *guess* maybe 1-2 hp tops. After you have learned to work the throttle without the secondary flapper, response would be greatly increased.
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Old Mar 4, 2006 | 01:06 PM
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I just did the tb mod on my 88 n/a, and it made a world of difference. Took out the secondary plates and linkage, kept the thermowax. There is not really reason to remove the thermowax, unless you like holding the throttle for several minutes everytime you start your car.

Without the secondary throttle plates, I noticed a whole lot better throttle response, quicker reaction to the throttle, but not a whole lot of difference at higher rpms.
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