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As title says, i will be running a IC and megasquirt if that makes any difference but im just wondering to save me some work if i dont run a second throttle body and just run the air filter off a custom inlet will it be ridiculously loud? cheers
 

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Its not actually for noise reduction. SC has to be throttled. If you are using just one TB you need to fit it before SC and use dummy TB on intake manifold. But if you want to keep stock TB in his place (on manifold) you need second TB to be fitted.
 

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Yes i will be keeping stock, only reason i asked is because i no of someone that is making a kit without the facility's to have the second throttle for smoother air flow but hey dont bite my head off, im gunna do it he way everyone knows
 

· Dr. Eunos
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Just fit throttle body pre charger and then a dummy throttle body on inlet manifold that's what I've done, works well
That's fine unless you want to run a FMIC. Adding a FMIC massively increases the throttled volume which is a bad thing for things like engine response and idle.
[/quote]

Correct
my JR set up with a dummy throttle body on manifold and no intercooler struggles a bit with idle after a quick blat, I put it this down to the the volume of air being an `elastic` fluid and having momentum so even when the SC is throttled on the other side of the engine bay the column of air in the cross-over tube will continue moving into the manifold if a second butterfly is not there to halt it, would as Mr Slow says be even worse with an intercooler as the volume of moving (=mass of) air would be that much more.
 

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This dummy body confusing, I allways thought you ran standard body with cable to the 1.6 body pre charger that opens and closes same time as stock body...
^^^^^^^^^^^^
This is dual throttle body setup.

Dummy TB is using only on one TB setup. Your stock TB fits before SC and dummy TB fits on manifold where your stock TB was.
 

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This dummy body confusing, I allways thought you ran standard body with cable to the 1.6 body pre charger that opens and closes same time as stock body...
Time for a history lesson....

Hotside supercharging kits from JacksonRacing and Moss, (but also including the now sadly no longer existing or no longer available kits from), BRP/SOT/FM all used a dummy throttle body in the OEM position on the intake manifold, basically just a hole with the correct take-off for your idle valve. You then placed the stock TB, (or in the case of the BRP/SOT/FM MP62 kits a much larger Mustang TB), on the back of the charger.

With no intercooler this setup just about works, but any form of intercooling required you to use a small Air to Water intercooler to minimise any lengthening of the intake tract. Add a FMIC and it's associate pipework and made your own life hell as the car just wouldn't idle properly and would die when you pulled up at lights etc. (There was one exception to this, the fapping excellent TrackDogRacing FMIC, which top fed the intercooler and reduced the intake tract as much as was possible, it wasn't 100% perfect mind you).

Then one day 4 or so years ago Mi5 (moderator on here) started making noises about a clever solution he had on his car, a pre-production kit from Performance5.

Turns out he'd got a throttle body in the stock location AND a TB on the back of the charger. Everybody swooned, I copied it as soon as I could, Phil owner of P5 had invented us supercharger owners nivarna, proper charge cooling with very few downsides.

Unfortunately for Phil every man and his dog copied it and I doubt he made any money from the idea, but everyone who has a dual throttle setup should thank him (and Mi5) for inventing/implementing it on an MX5.

Now it's almost de-facto to run dual throttles. I don't however as I don't like it's downside, a whine at part throttle.
 

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Just fit throttle body pre charger and then a dummy throttle body on inlet manifold that's what I've done, works well
That's fine unless you want to run a FMIC. Adding a FMIC massively increases the throttled volume which is a bad thing for things like engine response and idle.
[/quote]

Im not, probably why ive not noticed it much, but a good thing to bare in mind if i go FMIC in future!
 
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