Standard Gtr Plenum Modification

[boostin31]

Im thinking of just removing the standard ITB's and welding a throttle body flange on to the front.

Pros:

Looks neater, (no vaccuum bar, no throttle linkages etc)

makes it easier to tap in for vacuum sources

Something different.

Cons:

?????

Is this a silly idea? Been done before??

[blue_vl_t]

You are correct, i cant see why it wouldn't work.

Worth noting is that the intake runner is now considerably shorter which changes the characteristics of the engines response

somebody correct me if I'm wrong but i think shorter runners are best for a peakier, higher rpm engine in terms of efficiency.

To be honest, it would be great to see back to back results, if little difference is made, it will be tidier and easier to get to things in the engine bay.

You may want to check the ports are matched too, I assume you will run one large throttle body on the front.

[boostin31]

The throttle plates are only about an inch thick so i doubt it will make much difference to the intake length. Im pretty sure shorter runners will give it more low down response, then ill just wack a generic 80mm ebay throttle body on the end. bobs your auntie.

[JKR-32]

The throttle plates are only about an inch thick so i doubt it will make much difference to the intake length. Im pretty sure shorter runners will give it more low down response, then ill just wack a generic 80mm ebay throttle body on the end. bobs your auntie.

Negative sir. Longer runners for low down response and torque. Shorter runners for higher revving engines. An inch is a fair bit also. Say the runner is 4" long total and you take an inch off it. You effectively just removed 25% of the runner length.... (4" is just a guess, by the way, I have no idea how long they actually are)

[bubba]

This is pretty much what I did for my 32 but onto RB20 runners, with Q45 t/b on the front there's not a lot of room to get the bends onto the new GTR pipework but I'll worry about that after the engine is back in.