Thread: Bored Throttle Body or Q45 TB

In my past experience (T25 and T28 DET) I've seen some very positive benefits/throttle response with going with a bored Throttle body. I believe it was a 62-63mm, definitely not 64mm.

Now I'm going with a VET, and want to replace the puny 60mm TB. Since I want cruise control I can't use my high port throttle body, thus am thinking about either finding a bored lowport one, or just going straight to the Q45 9mm throttle body.

Searching through the old forum some folks mentioned worse throttle response on such a big throttle body. I am looking for good flow, the intake manifold and head is getting ported (port matched) and polished.

if you go with a ported or bored throttle body, or even the q45 make sure you pull the intake manifold and portmatch the throttle body to the intake manifold, otherwise the larger throttle body would just make the intake manifold a bottleneck, that way you will have a consistant transfer of flow.

Oh definitely, actually if you don't port the intake manifold you will technically get worse flow. Here is a quick sketch in Paint.



Having a smaller throttle body then the intake manifold would have less flow restrictions then having a large throttle body on non-port matched manifold.

nice depiction.

i would say a bored out throttle body would yeild good performance and flow. the q45 throttle is awsome but kinda a overkill, unless you are going big big power, with big turbo, and throttle matched intake intercooler piping. otherwise i think the bored out throttle bodies can yeild you just as much power without the overkill of the Q45.

Agreed, 90mm is a bit too much. I'm wanting something around 70mm. But 64mm is fine. The next hard part is finding a bored low port throttle body.

Im sorry to thread jack...
Vadim since this is your post you can feel free to edit/delete my post if you feel like it...

I was thinking on doing this to my DE, so basically what I need to do is port match the entrance of the IM to the Q45? to avoid the smaller transition right?

yes, you need to port out the entrance of the intake manifold the same diameter as your throttle body to have a smooth transition of flow.

you could bore your own throttle body, or ''port'' the throttle body, i dont have picture of the ones i used to do. the only problem is you would run into the issue that the butterfly is going to be the same size is stock.

you could port the inlet and outlet larger however im not sure how thats going to effect the transition of flow with the throttle body, the butterfly in fact might become a bottleneck

I'm sorry but didn't you say VE? Dosen't the VE have a different intake manifold and TB then the DE's? Kinda loss as I don't know much on VE's, but this is what I have always assumed. And why not N1 TB? aren't those suppose to be real nice on VE's?

What are the advantages a bored throttle body has, vs a Q45, that outweighs the extra cost?

Also read that some Q45 throttle bodies are actually 85mm. Not sure if that is related to certain years or what.

The 3.5L Nissan Pathfinder throttle body is supposed to be 70mm. Has anyone tried using one of these?

No worries bro . Q45 is quite a bit of an overkill on NA DE. You might actually loose too much low end power doing that. I would suggest just going bored 64mm .



I tried boring my own out. Didn't work out too well with the dremel. What's your method? .



It has a different IM but same bolt pattern. General school of though is, if you don't want cruise control use VE TB. If you want cruise control use Lowport. I have a spare lowport and it bolts right up.

N1 TB is $450, that's new from Gspec, not sure about used.



Q45 is pushing it. Also Q45 might not have cruise control either (which is why I'm switching).

Most new Nissans are drive by wire, makes it hard to use cable TB's.