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NEW TO ALL THINGS NISSAN
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Hi,

I've been back tracking through my page and remember thinking about getting a 'Throttle-Body Spacer'... I have an R33 GTS 2L Non Turbo

My question is :- What is a throttle-body spacer, what does it do, is it a good/bad idea & how much are they ??

Hope someone can help as I seem to have forgotten about doing this mod for some reason and may well do it soon, depending on whether its a good/bad idea etc..

Please reply asap

Regards - Martin.
 

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i mean i guess you could get a spacer that swirls the air to mix fuel better ... beyond that i couldnt see any benefit in moving the throttle body away from the plenium

anything you do with the 2.0 lump is pi$$ing in the wind though, just hold your horses and save the money for the propper ... it will come soon enough
 

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The idea of throttle spacers is to try and increase torque slightly by extending the effective length of the intake, but inn practice they don't really accomplish anything as they are far to short, save your money.
 

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Have you got any references for that tricky ?

Sent from my GT-I9505
yeah , look at the std plenum yourself , look how long the ******* is , is a 1 or 2 inch spacer going to make that much difference on a plenum with a runner length of probable 20" already?,

2 inches on 20 is only a 10% rise , doubtfull if youd see a 10% gain though

Dan
 

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I meant any kind of reference matetial link to how plenum length effects a torq curve .. I just don't understand how it could have an effect

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its like on old carbed motors , if you used a long trumpet rather than a short trumpet on a carb it increases lower end torque and power , shorter trumpet gives the oppersite of higher end torque and power, i believe that it increases the air speed as the air is under vaccumm longer , its not so dramatic to try and get the 'air fuel mix' like you spoke of earlier on on a turbo engine as much , nor on this style of manifold that has a 'dry runner' setup where no fuel actually touches the manifold itself , the injectors squirt directly into each port on the head , more air speed will increase the efficency of atmosiation (sp?) as more air speed will help disperse the fuel , but once under boost it has plenty of air speed ...

one thing i recently learned that by 'polishing' a manifold runner to a polished finish you actually loose air speed , to have a slightly roughewr finish such as a 200 grit finish in the runner you actually speed up airflow , but that is a whole different kettle of fish !

Dan
 

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Are the rb runners tuned?
.. I read that to see gains you would need a spacer 1 m long a least making it pointless

Sent from my GT-I9505
 

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Have you got any references for that tricky ?

Sent from my GT-I9505
I don't but if you research the subject I an sure you will find something.

its like on old carbed motors , if you used a long trumpet rather than a short trumpet on a carb it increases lower end torque and power , shorter trumpet gives the oppersite of higher end torque and power, i believe that it increases the air speed as the air is under vaccumm longer , its not so dramatic to try and get the 'air fuel mix' like you spoke of earlier on on a turbo engine as much , nor on this style of manifold that has a 'dry runner' setup where no fuel actually touches the manifold itself , the injectors squirt directly into each port on the head , more air speed will increase the efficency of atmosiation (sp?) as more air speed will help disperse the fuel , but once under boost it has plenty of air speed ...

one thing i recently learned that by 'polishing' a manifold runner to a polished finish you actually loose air speed , to have a slightly roughewr finish such as a 200 grit finish in the runner you actually speed up airflow , but that is a whole different kettle of fish !

Dan
On the right track although with carbs the stack was to increase airspeed to aid atomization, as carbs are notoriously bad at this, so anything that helps...

As for the throttle spacer, your right because in order to make any appreciable difference it would need to be considerably thicker than any I have ever seen, I think a lot of the spacer kits you see rely more on thermal decoupling which achieves very little anyway,
On a turbo engine because its designed around prssureised air there is even less point.
And you also partially right about the port and polish, its again more centered on N/A engines as once under boost there is little to be gained unless going for ultimate power, the smoothing obviously helps, but if you mirror polish the intake runners after the injectors it can lead to the atomised fuel dropping out, but its mainly because a slightly roughened finish will cause disturbed air which in turn aids atomisation and suspension of fuel, along with in increase in airspeed from removing obstructions to flow, with an N/A engine, as its just an air pump.
 
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