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ive got a cut and rewelded stock rb25 plenum on my rb25 motor. just wondering if there ok in terms of flowing evenly to all cylinders. just because i have recently done a compression test and the number 6 piston i think it is (closest to firewall) is down to 50 psi or so. the others have a fair bit of variance also.

i just wanna find out if people think thats what would have caused it or if it would have happened if it was normal style. coz ive got a rb30 twincam motor il be putting in soon but dont wanna put it in with that plenum if its gunna make the new motor do the same thing.

ive got a greedy copy plenum here also i could put in but im thinking il just use the standard one again for ease of installation coz i think the greedy one is sorta hard after looking at the guide. or is it really not that hard to put on in regards to changing a few pipes and throttle cable mounting and stuff and i should use the greedy copy one with 80mm throttle body?

this is the one in my car. would it flow evenly and stuff. the vl turbo guys have the same sorta ones and its very common for them to have it made like my one. one of the main shops even uses that sort on a 8 second drag car rb30. i think

r33skyline015.th.jpg

also, will i have the problem with the bit hitting the bonnet with this current plenum since its different? cant remember where they hit the bonnet with rb30 bottomend with rb25 head.

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i did this to my r33 and added a 90mm throttle body, i actually got an extra 13rwkws and now i upgraded my turbo to a t67-25g on stock internals running 304rwkw and its fine, it improved the response also. and doest hit my bonnet but mine is just a rb25 bottom, my throttle cable also reaches

yer they used dog turds when they welded it bro

the look of the weld mainly determines the quality of the weld. In your case is slapped on there and that usually means a total lack of penetration. Sooo... it means it will crack or leak, neither of which you want to happen.

Good call on the low comp. Sort the motor before messing with plenums.

Besides that, i dunno why you'd go to the trouble of welding it up for poor flow etc. when a greddy knockoff plus a little bit of work will only set you back a few hundred bucks.

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