BDC

Roger that. I was mistaken. I haven't used that thermowax in a very long time but I knew it had something to do with cold idling.

B

BDC

Absolutely. It will be a giant vacuum/pressure leak into the atmosphere. There will be two holes leftover if the thermowax and the opposite side mechanics are removed.

B

BlaCkPlaGUE

I read a writeup on the TB mod a long time ago saying that you had to plug the coolant passage that runs through the TII throttle body. You don't, it just leads to a connecting pipe on the other side of the TB that you can cut off. It does not connect with the vacuum of the intake at all.

I really want to get mine ported like some of your guys's, that looks awesome! I LOVE how some of you guys even ported the damn shafts for the throttle plates for more airflow! thats wicked!
Im working on my TII TB right now, dissassembeling it, so when its down to nothing, I should send it out to get ported.

vincentwashere

port it yourself, its easy im doing it right now, find some pics and try to replicate it make the center sharp and smooth for more flow

BlaCkPlaGUE

I have no porting experience, I have no tools for porting, I have no idea what im doing. I don't mind sending it away to get done. It would probably cost less sending it than buying the tools and it will get done properly.

We need a 'porting' guide. Not on a specific part, but just on porting in general, hints/tips, tools needed, etc.

BDC

Send it to me, BlackPlague. I will do a killer, unparalleled job on it. Toss me a PM.

B

Modified 7

so if i port my na throttle body...its pointless?

patman

iTrader: (3)

porting tools are cheap. buy a dremel - $20, and a set of metal cutting bits for it $11, and maybe a grinding/polishing kit -15?

so thats like...40 bucks total, and you can port lots of parts with it, not to mention various other jobs that it can be used for.

as for porting itself...theres really not much too it. the trick is to visualize how you want it to look when its done, then just take off a little bit at a time until youre there. try to make all edges rounded and smooth, so that it will flow nicely.

pat

NZConvertible

I wouldn't say pointless, but you have to expect only very small gains. The stock TB is huge compared to the NA's output, even on a modded engine. Remember lots of people have made over 400hp (turbo'd) with exactly the same TB. Given that few NA engines with the stock manifold/TB make even half that, you shouldn't expect much from slightly improving flow through something that isn't much of a restriction to start with.

Also keep in mind that I have not seen even one person offer conclusive proof of the gains from doing this, on NA or Turbo. By that I mean before and after acceleration times or dyno results. Lots of "It felt better" or "It felt faster", but nothing concrete. Also a lot of "It looks so much better", as if that means something...

pengarufoo

What metal cutting bits are you going to get for $11 that will survive long enough to even finish one throttle body? Let alone various other jobs? MAYBE you will get one carbide bit for that price, dremel brand, and it will not last and be too small!

For good quality carbide burs of various shapes and sizes you will easily spend $100+ for a set, not to turn anyone off from doing this themselves, but it's a fact. I strongly recommend doing this yourself as it's not that difficult and it usually costs far more than the cost of tools to have someone else do this, and the tools will be with you for other porting jobs in the future.

In fact, if you have never ported anything before, the throttle body is by far the best place to start before you even consider touching engine ports, you have to start somewhere so why not here.

Check out http://mscdirect.com for rotary tool carbide bur sets.

You can also assemble a manometer for only a few bucks and with the help of a shop vac you will be able to easily flow test your porting to see what works and what does not, and compare your modified version to the stock one....

Someone posted photos earlier in this thread of a pretty decent porting job and they had even narrowed down the throttle shafts to an aerofoil shape removing the bolt heads altogether. That throttle will likely flow better than any of BDC's photographed throttles, considering the throttle shafts were all left stock in his and reducing those to an aerofoil will have more effect than any polishing of the bores will have.

Also if you would like to take it further, and have aluminum welding capabilities (I do) you can build up the leading edge of the port dividers in the throttle body, where they meet up with the throttle body walls. This will permit further streamlining of the leading edge near the walls which almost always starts abruptly in all these ported throttle bodies. I prefer to do this while I am filling the holes left from removing the throttle shaft, it gives you more material to work with when trying to get the leading edge smoothed out.

patman

iTrader: (3)

carbide bits for dremel are 5.00, and will last through way more cutting of aluminum than one TB. the TB is very soft compared to a carbide bit.

you can also get various stone bits for finish work and for cutting stuff harder than aluminum.

believe me, ive done LOTS of porting with a dremel, and while the dremel stuff isnt great, it is more than adequate.

pat

pengarufoo

Dremel bits are too small in my experiences, I've tried them as they are cheap but you get what you pay for. The shanks are made from cheap steel that is very easy to bend and with such a small diameter it can be very difficult to get a smooth shape in your porting work, you will end up with small gouges and pockets, and often end up removing more material than you planned to smooth it out. If you move up to a larger one you have to make sure the quality is good or they will not be balanced, as it's spinning at very high rpm the bit needs to be balanced... though this doesnt really matter with the tiny diameter dremel bits which are not even close to ideal for porting work.

Get a book on porting, look at the recommended bits, nobody who has done much porting would recommend using tiny dremel bits for aything but small detail work, it wastes time, money, and is very difficult to control the results.

Not to mention dremels selection of carbide bur shapes is very poor.

If you can make it work with the cheap dremel bits more power to you, I don't think it's a good idea, but if you read my post I am very pro DIY in this context so go ahead and try all the options! I wasted enough money buying dremel bits before I knew any better to buy a very nice industrial quality carbide bur set that would have worked with the dremel. I've since learned my mistake, just trying to save someone else the wasted time & money. The dremel bits are cheap, but they do not last... when you replace them often it's no longer cheap.

ScrapFC

iTrader: (5)

If you have an air compressor and a portable tank or (ideally) a nice compressor with a built-in tank you can get a cheapie air die grinder for about $20 that will do the job well. Otherwise you can get an electric die grinder for about $50. I prefer the air version because it has a softer stall. (Doesn't jerk and break stuff if the bit binds in a corner)
I got a set of 4 6" carbide burrs on eBay for $30 shipped and they meet most of my cutting needs. A 1/4" split mandrel can easily be made by slotting a short length of steel rod you can get for less than a buck at any hardware store. I cut sandpaper into strips, stick a strip in the mandrel and use it for smoothing and polishing. (Use wet/dry and keep it wet. It's amazing how fast it works.)
I agree that the TB is not a restriction in the airflow path. However, turbulence hurts flow and there's plenty of opportunity for turbulence in the TB. That's what I went after when I modded mine. I didn't try to hog out the passages for more area but instead concentrated on removing any flat faces and irregularies that would make the air tumble.
I know I gained a few HP, and my shift point moved up 500RPM. (Very handy for autox!) It was pointed out to me that if I had any HP gains, it was probably due to the extra set of butterflies having not opened all the way. IIRC, they weren't opening all the way so that makes sense. However, since they are apparently open anytime the motor's warm on an NA how could they have been affecting my throttle response? I KNOW I had a nearly 1/4 sec throttle lag before and it's gone. I now have no perceptible throttle lag. I suspect (Unfortunately I'm not very well educated yet on flow dynamics) that the turbulence is affecting the rate that the airflow can change? Maybe someone can prove/disprove this and maybe point me in a good driection for study...

vincentwashere

u dont really need any experience. its like useing a drill. eyeball it, sometimes the grinder tool if u using compressed air tool it will hop around. but its fine. doesnt need to be perfect. thats why you polish. u get a sanding wheel or sandpaper and just sand it down. i used 80 grit and then get some 400 grit or wutever and get all the scratches and dimples. dremels are worthless in this process, it will take u FOREVER. ill post some pics of mine later after i repolish it. oh yeah remember to get a course grinder bit (carbide). if u get one that has the cutting slots too close it will not work good on aluminum