RB20 intake manifold?

[stldrifts13]

Ok, so i did a little searching( maybe not enough, so no flaming please) but has anyone on here modded their stock RB20 manifold so that the throttlebody is facing the front of the car like the greddy, RIPS, etc. im sure i've seen this before, but i can't remember where. I remember it looking like they just cut off the front of the mani, welded it closed, and then re-welded it to the side of the manifold. it seems like a cheaper alternative to the high priced after market manifolds. Im not really looking for HP gains, i'm really looking to do it for convenience. if anyone has any knowledge of this or has a link to somewhere that does, i would appreciate it.

[themadscientist]

the manifold was not designed to flow that way, the runners meet the plenum at 90-degree angles and I would expect the first two or three cylinders to get starved. I am not saying the OEM layout gets me excited either but at least it was designed with that TB placement in mind. I would prefer making a plenum that bolts onto the OE lower manifold.

[stldrifts13]

yeah, i kinda figured air distribution would be a problem. looks like i need to stop being a cheap *** and shell out the money for something new. thanks for the input!

[Bronze MFP]

is the oem manifold really that bad? if you're not going for crazy HP (like 400+) it doesn't seem like a bad design to me. decent size surge tank, decent distribution to the runners (might feed 3,4 a little more than the rest, but show me a mani that wont favor a few cyl over the others)

[stldrifts13]

im not looking for high hp at all, just looking to making working under the hood a little easier. it's all for convenience and i don't feel like paying out the *** for an after market mani. i just think that it would make the engine bay look a little cleaner too. im fine with the stock one for now though

[nizmo zilvia]

OEM isn't bad at all. Reason some get it like me because of the piping and better air flow it would receive. But then again you'll kinda pay off your @ss for one. Its actually worth it. A lot easier to work on the engine having a custom one built. My .02 cents.

[Sil240]

It really is sooo much easier working on the motor without that huge ITM.But if your going to have someone weld up your stock ITM, why dont you have someone make you a upper Plenum.Or call Top Hat motorsports and BEG him to make you one.Or buy a Knock off Greddy RB25 ITM and put some elbow grease into it and then have a adapter plate made to fit the RB20

[RB20Skyline]

From what I understand the longer intake runners of the GTS plenum areok up to 500hp. Above 500hp use the stock GTR intake plenum, whichhas shorter runners / multiple throttlebody's, which is suited to higherHP applications and throttle response. There's an adaption kit you can buyfrom Japan for the stock GTR plenum conversion on RB20DET's. I think ithas a conversion plate for the bolt pattern as they are different.

Also be aware the stock GTR intake plenum has flow problems aroundI think was cylinder no 6. The upgraded Nismo intake plenum fixes thisproblem.

The trick on the racing RB20DET's (with a stock GTR type of intercooler)was to make the intake pipe cross where the fuel regulator is located,then do a curve bend to the throttle body. It worked up to 460hpwithout problems. From what I understand this design supposedlykept the intake piping away from the radiator fans flow, etc thuslowered intake temps.

[stldrifts13]

hmmm, i didn't know there was a conversion kit for the gtr plenum--->rb20. that sounds like a good idea if it's not that expensive. like i said though, this is all for convenience. im not look for high hp, just a less of a headache when i open my hood. i really appreciate all the input guys, thanks!

[JerryRigRB240]

You can also saw off your lower runners before the injector holes and weld on a 26 plenum to it.

[Sil240]

hmmm, i didn't know there was a conversion kit for the gtr plenum--->rb20. that sounds like a good idea if it's not that expensive. like i said though, this is all for convenience. im not look for high hp, just a less of a headache when i open my hood. i really appreciate all the input guys, thanks!

Anything RB26 or JAPAN is not going to be cheap.I remember hearing about this but for the RB25, I guess they made one for the 20 also.If your gonna spend that Money have someone make you a uppoer plenum just to route your IC.

[stldrifts13]

yeah, i think you're right about that. anything gtr is expensive.....however, welding the gtr plenum to the rb20 runners sounds likea good idea, as long as it's reliable. and would there be any tuning required? i think the black plenum would be great considering my valve cover is black too. But that sounds way too easy. has anyone seen that before? pics?

[JerryRigRB240]

Hope that helps bro

[RB20Skyline]

You have done a awesome job with that intake plenum JerryRigRB240.

I don't think the plenum itself would be expensive but I guess thethrottlebodys, etc would.

[240SX GT-S]

I have an RB25, and like you, I found the throttle body/crossover pipe annoying. So I cut it out of the middle and welded it to the front. I saw another guy on here somewhere do it. He had a red S14, from Austrailia. I try to get a hold of him to see how it ran, but he seems to have dissapeared. I'll let you know how mine runs when it gets to that point, if you're still interested.

[stldrifts13]

I have an RB25, and like you, I found the throttle body/crossover pipe annoying. So I cut it out of the middle and welded it to the front. I saw another guy on here somewhere do it. He had a red S14, from Austrailia. I try to get a hold of him to see how it ran, but he seems to have dissapeared. I'll let you know how mine runs when it gets to that point, if you're still interested.

Yeah, i'd love to hear how it runs when you get it finished. JerryRig, that is exactly what i was looking for. yours looks really clean. was there any tuning involved with that, or did it just bolt on and go? how much was the plenum?

[JerryRigRB240]

I think there's a plenum on ebay for 275.

If I were you I'd try to get some importer to get one for you at a better price, cause imo that's too expensive.

I wouldn't say there's tuning involved, but I'm running a very tuned setup so I'm not exactly sure what you'd have to do for a stock motor.

[stldrifts13]

I think there's a plenum on ebay for 275.

If I were you I'd try to get some importer to get one for you at a better price, cause imo that's too expensive.

I wouldn't say there's tuning involved, but I'm running a very tuned setup so I'm not exactly sure what you'd have to do for a stock motor.

yeah, i saw that plenum. $275 seems like a lot. From what i've seen on here, most people with custom or aftermarket plenums have said they've gotten an increase in throttle response. is that because of the shorter piping? and yeah, my motor is stock minus a few bolt ons. im hoping i can get away with not having to tune it, cause christmas season killed my bank account.....

[JerryRigRB240]

Yeah, there's an increase in throttle responce, both from better flow and from the shorter runners/ic piping.

The downside to that is you lose a lot of midrange torque... and the 20's lacking in that area as it is. Basically your engine will be less streetable and more responsive on a track, so if you're not on a track a lot, or running high hp #s it probably won't be a good idea.

[nissanman04]

u won't NEED a tune, but it would be beneficial

[stldrifts13]

Yeah, there's an increase in throttle responce, both from better flow and from the shorter runners/ic piping.

The downside to that is you lose a lot of midrange torque... and the 20's lacking in that area as it is. Basically your engine will be less streetable and more responsive on a track, so if you're not on a track a lot, or running high hp #s it probably won't be a good idea.

yeah, this car is my daily and needs to stay streetable until i buy another car. im thinking i might just stick with the stock one for now. but when i do cahnge, i think i will definitely go with the gtr plenum. Unless i can come up with the cash for this bad boy....http://www.tweakit.net/shop/product_inf ... ts_id=1453

anyone heard anything about it?

[nizmo zilvia]

Yea I seen it. I just didnt want to spend that much when I could get a full new intake manifold for cheaper.





-------^^^^^^^^^^------- 96' Maxima TB

[jdmser]

Get your o2 housing off your steering shaft before you start messing around with this.

[greenmonster80]

Yea I seen it. I just didnt want to spend that much when I could get a full new intake manifold for cheaper.





-------^^^^^^^^^^------- 96' Maxima TB

Ok I'll bite.....From where? I'll buy it today if it the same as your pic..

[nizmo zilvia]

[email protected]

Email him and tell him that you saw it on nico from me.

[stldrifts13]

Get your o2 housing off your steering shaft before you start messing around with this.

Lol, funny Tom. Im working on that too....car's still running strong too. NO more overheating!

[dwnshfter]

for [QUOTE=nizmo zilvia][email protected]

Email him and tell him that you saw it on nico from me.[/QUOTEfor real? i want one too! price?

[Yellow4g63]

Don't forget to tell them about what you needed to do to make it work. Like the adapter plate you need to bolt on the stock Throttle Body.

[nizmo zilvia]

I don't wanna high jack this thread so if you interested in this message me on AIM: Chuki RB . What I'll do is email him and tell him small problems I encountered like wrong iacv, tb for maxima not rb, and another small one. But its nothing I couldn't fix or spend a large amount of money. I'll let him know. Thanks Yellow.

[RB20Skyline]

Here's the Nismo intake plenum kit I was talking about. Have a look atthe last runner (cylinder 6) compared to the stock GTR intake plenum -

http://www.uniqueautosports.co...m.jpg

Found it here -

http://www.uniqueautosports.co...e.htm