hey guys can someone please explain the damned TB mod to me...i know its for more power..and thats what we want of course. now, how do i go about do this mod?

 

it is the worst thing you could do to a running rx-7.

and no you wont get any more power, just a bad idle.

 

hey if you want i can do an even trade with you for my modified tb. i want to go back to stock. just shot me a pm

 

you'll find most people mod there TB and want to go stock... good luck doing it if you do. i for one will trade you mine as well.

 

The people who have done the TB mod and then want to go back to stock are the ones that screwed it up.

That said, I don't recommend performing the TB mod unless you have a real reason to do so. You won't gain any more power, and if your throttle body is working properly (or you have an NA) you won't see much in the way of improved throttle response.

 

here's a great write up...

http://rotaryresurrection.com/2ndgen...s_removal.html

 

The link above should not be called "emissions removal". Removal of the thermowax and dashpot is not a good idea on a daily driven car. These are race only modifications that have no benefit (only downsides) on the street.

 

thank you aaron your a well eduacated man ha ill definatly not be doing th TB mod now...but whats the intake mod that has something to do with removing some butterfly thing...crap i dont remember at all to be honest something in the intake..

 

Done this while modifing my intake, removal of emissions etc. If you are mechanically minded then all you have to do is look at the TB and you'll know what needs doing, removing the first set of butterfly valves etc.

As modding mine wasn't a singular mod I cant say what the improvements were, but I have no problems with idle etc, even during the cold winter months. I had two TB incase I did screw it up but I didn't. It is nice to give it all a clean and service at the same time.

Good luck

 

http://fc3spro.com/TECH/HOWTO/TBM/tbm.html

there is a link to a how to do the throttle body mode (including removal of the secondary butterflies). just ignore the parts about taking the thermowax off if you don't want to do that.

 

DON'T DO IT

I did it a few years ago and after a few months of having it I had to buy a new untouched TB.

PROS...

If your car is ported or boosted you may see 3-4 HP out of this if you port the TB in addition to the gutting of it. You will see NO improvement of performance.

CONS...

When you start the car in warm or cold weather (mostly cold) it will not hold idle for at least 8 minutes of idling or 3-4 minutes of driving. Basically until the T-stat opens up. You need the wax pellet just because its a total pain in the *** and quite frustrating to have your car constantly die on you when you take it out of gear.

I guess if you remove the primary throttle plates and retain the wax pellet you should be ok.

 

This modification got started when it was found that Turbo's ran the coolant through the throttle body. This helps bring the intake air temp up if there are sub freezing temps.

But as a draw back it also heats the throttle body on warm days. In some high performance cases this can result in detonation or other hot air issues.

Now non turbo FCs do not have to worry about this as the coolant line is external to the throttle body.

In some high performance/race cases you would not want to heat the throttle body up on a Turbo, so you perform a partial or complete Throttle Body Mod and in many cases give up the car idling and running correctly at colder temps.

But the simple solution is to remove the coolant from entering into the throttle body on Turbos and have it only enter the Cold start assist thermovalve. But to do that is above the ability of many people as it requires drilling and tapping as well as adding threaded to hose barbs.

Here is a picture of a Turbo throttle body with the mod performed, but so that it retains cold drivabilty. What you can't see is that the back coolant passage out of the cold start assist valve has been drilled and tapped and a plug placed in so that the coolant can only run through the cold start assist valve and not into the throttle body. The hose from the BAC is relocated to the new drilled and tapped right angle threaded barb in the picture, instead of through the intake manifold and throttle body to the back plate of the motor.



Now on the non turbo the 2nd set of throttle plates is also used to keep the owner from abusing the motor when the engine is cold. So removing them really only helps at low coolant temps (which frankly you really do not want to be abusing when cold anyway). There is no real performance gain doing this mod on a non turbo car, since it does not have the same issues as the Turbo with the coolant routing.

 

I'm actually impressed at the responses here! A year ago you'd have found people on here proclaiming the superiority of the tb mod. Now we've got smart people responding!

It's amazing how many different "mods" are popular for these cars that do nothing at all and in some cases hurt performance. I think most people would be shocked at how few things you really need to do to these cars to make them quite nice as well as what things you can not do and not miss.

 

so now that i have royally screwed myself doing this tb mod 2 years ago. would anyone have a untouched 87-88 tb to sell to me?

 

if you are sweating the possible 1-2 hp increase from the TB mod, your car is too slow anyway

if you are sweating the possible increase in detonation from coolant running through your TB, your tune isn't safe enough

one of the best things I did to my car was put my thermowax and dashpot back in.