does 64mm throttle body needs intake manifold inlet to be bored to same size?
 

Like the title says, does 64mm throttle body needs intake manifold inlet to be bored up to the same size as the throttle body to gain performance? Or do they mate up to the same diameter without modifications?

Believe me, I tried to search but could not find any posts regarding this.

You may find these helpful:

https://www.miataturbo.net/attachmen...ine=1366153558
JD/UK/EUDM "Squaretop" manifold upper plenum throttle body inlet

https://www.miataturbo.net/attachmen...ine=1366153558
Squaretop with Skunk2 gasket (notice the "ear" at the top of the photo with no gasket coverage)

https://www.miataturbo.net/attachmen...ine=1366153558
Potential vacuum leak on backside of throttle body, right next to "ear." Pencil line represents the overlap between the manifold and the throttle body... not much meat there.

https://www.miataturbo.net/attachmen...ine=1366153558
OM NOM NOM NOM!!!

https://www.miataturbo.net/attachmen...ine=1366153558
Throttle body to manifold. This would be the material you need to remove for a smooth transition. This is a tracing of the throttle body, NOT the gasket. I did this with the gasket removed.

https://www.miataturbo.net/attachmen...ine=1366153558
For fun: Skunk2 gasket against stock NB throttle body.

This is all still sitting in my garage, LMK if you need more pics.

Edit: Put some tags on this thread so others can find it :party:

/\ Very cool thanks gordon

Very welcome, I try to give back where I can.

It would be nice to hear from some other guys running the 64, I'd like to see how far they went with port work, if any.

Wow, thank you so much for the detailed reply, what happens when you line up the gasket with the intake manifold that has the lines drawn from the bigger throttle body? I assume that the gasket outlines are bigger than the drawn line?

There is play / slop in the mounting holes, when you install it open the blade and look and feel to get everything centered before torquing the bolts. Of course this is after you port the manifold as in the above post. Also to note, mine is a 94 car with a square top, and I tried to use the '94 TPS, but with the adaptor, it would hit the valve cover. I ended up changing to a 99 TPS and pigtail. IAC valve worked fine.

I'll dig out the parts and take a look tonight. I think I completed the radius section that I couldn't draw with my pencil using the gasket (it was blocked by the throttle butterfly and shaft.) But I'll see if I can't get a pic. If memory serves, the gasket is damn near perfectly matched to the throttle body itself.

I seem to remember either Emilio or Savington saying that they just pop these on and run them, but I'm too lazy to go find the comment. Its probably buried in the broken throttle shaft threads.

They work and may gain a few whp up top without matching. More gain when matched. If your rules (no rules?) allow it, match the darn thing.

I couldn't have said it better myself :party:

Holy thread revival Batman! I'm running a basic intercooled setup (NA 1800 Eunos import) with a td04l13t at 15psi with a mspnp2. I'll be ripping a quick power run today then installing the ported inlet and skunk2 followed by another power run in the next few days to see what's what. The dyno is the best in the area and has a built in weather station all sorts of fancy features so is the best I can do without fitting the thing at the garage on the same day.

I do have thermal spacers for the head to inlet and TB to inlet but I really cant see this affecting results much under dyno conditions.

I have no clue what's going to happen but i'll post up back to back dyno sheets on here if any of you guys are interested.

https://www.miataturbo.net/attachmen...ine=1467795825

https://www.miataturbo.net/attachmen...ine=1467795825

https://www.miataturbo.net/attachmen...ine=1467795825

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You better blue locktite every threaded thing on that throttle body.

Ive done the stop screw already but everything?

Some QC issues been going on or what?

Over the years we have had many reports of the screws/nuts working loose. Not the ones on the throttle shaft or the butterflies mind you, but definitely the rest of the smaller ones. Just get everything set up the way you want it and then R&R with some appropriate (read: non permanent) threadlocker.

The color is not my bag but I do like the powdercoat, looks like it came out really nice. I'm guessing with the 2 post count you don't have an intro or build thread? You should go make both :bigtu:

Essentially, yes. We view the Skunk2 as a "throttle body kit". A starting point.

Between myself and a few other vendors, Skunk2 has been thoroughly informed of each concern in detail going back about 4 years. They just don't care. Thus why we are working on our own TB for 2017.

Cheers for the heads up guys! :D
I'm a UK Eunos owner and have dipped into here for bits of info but not got balls deep yet because all the info is available without looking stupid by asking dumb questions and annoying people (I know you guys can be savage ;) )
I'll throw a bit of a build thread together this week :)

Car dynoed at lunchtime gave the following so lets see if she makes gains with the new system.

https://www.miataturbo.net/attachmen...ine=1467820628
https://www.miataturbo.net/attachmen...ine=1467820628

https://www.miataturbo.net/attachmen...ine=1467820628

https://www.miataturbo.net/attachmen...ine=1467820628

looks like a nice little car!

Thanks man. She was a POS when I picked her up but quite a looker now and has the performance to back it up with the turbo :)

aside from the tsi and vented flip up panel, nice!

Thanks man, the tsis and vented lid are two of my favourite parts :sad2:

:D

different strokes!