How to Make an na Throttle Body into a Turbo one.

**allmazda** · 1-31-08, 0:41

I got an offer to buy my new TB for my 88 626 Turbo. I did not have another new one for the gen1A turbo so I got to thinking and yep all of the sensors are the same for both turbo and na TB's. The only diff is in the extra vacuum lines for the na. So off went my semi-new TB to its new home and on went a na tb to my turbo.

Only regret is I was in a rush to get it done and could have choosen better looking bolts. Well I had to use what we had on hand. Due to my back I can not do very much these days and my Nissan buddy was willing to do the swap so I did not complain.

Here is the before shot of a new 88-89 NA TB. Notice the vacuum lines on top.

I did not take any pics of the "amputations" in process but what he did was cut the vacuum nipples off flush and then drilled and tap the holes so we could cap them. Could have used vac lines to loop them together but it only took him a few minutes to operate.

Here are some shoots of it installed.

End result is it fired right up. The idle screw had to be adjusted to idle it up some. Runs fine with no problems.

**compnut21** · 1-31-08, 3:02

does the non turbo tb have any hp gains or losses? also nice work.

**allmazda** · 1-31-08, 8:34

No gains or losses because they are the same. The butterflies are the same. The timing advance on a GT is computer controled. On a na it is controled by vacuum.

**Zach** · 1-31-08, 10:38

Now just make an SVO 65mm Throttle Body Work and I'm sold

mazda mx-6 gt · 2-2-08, 0:22

lol what is the point of the larger throtel body
jake

**compnut21** · 2-2-08, 1:19

more air flow?

**Manifest** · 2-2-08, 8:24

I always figured that I could use the lines for things like a turbo boost guage, and rising rate fuel pressure regulator. But since my original is still good, no reason to test it yet. Also if mine was to go bad, I could always swap the electronics off the NA one and I would be good to go. All good ideas, and good to know that some of these are still around.

**allmazda** · 2-2-08, 9:14

I do not have a boost gauge but that is a great idea.

The best way to get more airflow would be to drill the smaller hole the size of the larger hole and take the larger linkage and butterfly from another TB and install that where the old smaller one went. There is enough material to do this.

**monoxidechild** · 2-2-08, 10:19

why not just plug them with vacuum plugs? same thing you did, but with no real work involved

**allmazda** · 2-2-08, 11:10

Yes we thought about doing that. But with a cut off wheel and drill press it took about 5 minutes for him to cut them and drill the holes for the tap. Took the most time finding enough of the same bolts to use.

He is used to working on the 240sx's (I am not sure what the JDM engine is called) and his customers like a lot of boost. The turbo does not have vacuum before the TB butterflies and he said it might blow the caps off. Not likely with my 326K stock turbo but he over does his stuff.

So yes I could have but time was not an issue.

**monoxidechild** · 2-2-08, 12:10

understandbale.

its cool to see a brand new TB too. havent seen one so clean, even right out of the parts washer, they dont look that good.