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Hi All,

My RB20DET plenum arrived yesterday so this weekend i'll be installing it. My question is that when I changed the exhaust manifold I found that i had a bunch of broken exhaust head studs. Am I in for any simular supprises with the intake side of the engine?

Cheers,

Ian

Edited by GTST4Newbie
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Thanks guys. I'm still working on modifying the plenum to fit an additional 6 injectors so I can run 2 fuel rails. One with RB20 injectors and the staged set with a set of gtr 440cc injectors. The goal is to be able to get a very economical low end tune on the RB20 injectors but have the fuel for 25lb boost, and 400 Awhp.

I'll pics pics of the progress as it happens.

Cheers,

Ian

  • 2 weeks later...

Well its done..!

It took working on it on and off over 6 days to finish it properly. I had to re-work the water plumbing under the plenum, and also had to remove the hydraulic line from the clutch master cylinder to get it on the engine, but other than that it went on fairly easily.

I took the opportunity to do an oil and plug change, and installed a full flow oil system (cooler and remote filter) at the same time.

Detailing things as i went, the plenum is metalic blue with a lot of clear coats, fuel rail is modified with new 1/8th bsp fittings silver soldered onto it, and painted flat black. The throttle cable is off a R31 skyline, which is about 20cm longer. I also made a alloy throttle cable bracket.

I'll be painting the 4" intake piping the same colour. The rocker covers will be either polished or painted silver metalic, and i'll re-paint the coil cover satin black to finish detailing things.

As for how it works, well its still being tuned. Its certinaly no worst than the stock plenum was. Inside the plenum there is 6 50mm velocity stacks on each port, so it should be a little better in top end flow. It doesn't seem to have sacrificed any low end that i've noticed.

Attached are the before and after pictures...

Cheers,

Ian

post-26553-1152333118.jpg

post-26553-1152333251.jpg

post-26553-1152333278.jpg

post-26553-1152333304.jpg

Edited by GTST4Newbie

Rocker covers will be polished alloy or silver with a clear coat. Coil pack cover will be satin black. Intake pipe will be painted blue like the plenum.

I'll be running 25lb max once i get the 1600cc staged injector installed before the throttle body. Next upgrade is installation of the nismo gmax twin plate clutch i just scored. Hopefully that will happen next week.

Not so much looking for a specific power figure, though around 400hp at all 4 wheels would be nice. I'd like low 12's or better on the 1/4 mile in about 2 weeks...

Cheers,

Ian

Edited by GTST4Newbie

Made by stryder in taiwan. Was a bit of a bitch to install but its worth it now its installed.

Still tuning the car, and am running 1 bar boost with the gtr injectors in it again. All seems good so far.

I'm adding a 1600cc staged injector next weekend so that will allow 24lb and a final tune to around 350 or so hp at the wheels.

Adding a nismo twin plate clutch too some time later this week too...

1600/6 = 266cc per cylinder + a 440cc gtr injector= about 700cc per cylinder.

This means i'll be running all injectors at about 75% duty at the most at max rpm.

I'd maxed out the standard GTR 440cc injectors at 100% duty with a 12:1 AFR with 20lb boost with the last tune at 6500 rpm. More RPM would have meant it would have been around the 14-15:1 AFR at 7500 which would have been a melt down. Thus the addition of a staged injector.

Edited by GTST4Newbie

http://cgi.ebay.com/ebaymotors/Nissan-Skyl...sspagenameZWD2V

But I got mine for $399 USD + freight. Cost me about 550 AUD delivered, and they kindly declared the package as being worth $100 so no import duty or GST etc.

Nice... Good pricing...

What i did dig up is that it uses the standard runners... Damn half english explinations...

Is that true... What throttle body did u end up using?

Edit: I have sent an email to the seller requesting more info. Also they had rb20 and 26 manifold listed but no 25's so i have emailed about that too. Thanks for helping out mate.

did you do any back-to-back testing?

i.e. a run before the manifold was installed, and then again afterwards? would be interesting to see what (if any) difference it makes...

also, where do i find information on this R.I.P.S. manifold i keep hearing about both here and on SDU?

is it worth buying (i.e. are there any power gains) or is it more just the convenience of having the throttle body at the front of the manifold?

reason i ask is there's been results that show that with some manifolds, you will actually go backwards in power/response/flow...

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