Is ~400whp realistic with this?

[cschepp]

Plenums won't fit unfortunately. If they would fit ou would see many 20 guys running the affordable the front facing greddy that is made for the 25. Injectors I believe would difference because the 20's are top feed and the 25's are side feed. One way to take care of that though would be to grab rb26 injectors and resistor pack and then later on you can just upgrade to bigger top feeds which have more potential in the hp area. I have seen side feed injectors top off at 1100 cc injectors and top feed are easily available for pricing at a higher range. I personally ran a 25 with rb26 injectors and modded rail to fit the 25 plenum. Great investment if you want big power!

[BongRips]

Well this is my plan for now, I think its fairly decent. Upgrade my 20 for now and run it next summer, then the year after I'll swap it for a 25 as my buddy will have fash for my 20 by then. That way I can run a quick 20 for a year, then get like a g to 1500 for my engine, tranny, ecu, etc as it will be modded which I could put towards an rb25 and injectors, plenum, and whatever else I need to swap out to run it nicely.obviously the 25 will make a lot more and handle a lot more power than a 20, but I can wait a year to do that swap, I just want something to put down some decent numbers for a year or so

[BongRips]

Just realized I should probably upgrade my coilpacks too. I didn't notice any red dust on them when I changed my plugs 5k ago but doing a build it would be good to upgrade those right? And I never paid attention to the coilpack holders, are they plastic or metal? And for 30 bucks, should I throw on new aluminum ones? What would be good oil and water pump upgrades and oil cooler and fpr's? Just wanna get my list as complete as possible so I can have a price guideline to know how much wiggle room I'll have for other random stuff

Edit:

Would the N1 oil and water pumps work fine? I saw that the N1 oil pump is over a grand cheaper than the tomei one and I'm hoping the N1 is good enough. Also, would a cheap oil cooler kit like this work? http://item.mobileweb.ebay.ca/viewit...id=76926851505
I couldn't find any direct fit kits for the rb20 but saw the greddy kits for the 26 for around a grand and I'd like to be able to save a few hundred with a cheaper kit

[BongRips]

And if I were to get a more conservative tune for around 350whp, would it be a lot more reliable? I plan on doing some weight reduction too to get the power to weight ratio better. Hood I can go for gtr or carbon, how much lighter would carbon be? And would it be possible to get down to ~2700lbs on a gts-t with two 10" subs installed where the rear seat would be with a fibreglass box? Doors are replaceable with gtr doors which are lighter right? What about trunk? And would racing seats be lighter than the stocks or are the stocks lighter than the average weight racing seat (none carbon or lightweight models)

[TheyKilledKenny]

The less boost you run the more reliable your vehicle will be. N1 pumps should more than adequate for your goals (I run them). You have to remove alot of weight to really experience any difference in a vehicle, unless ur a hardcore dragstar and have consistent quarter mile times. The old assumption is that 100 pounds less weight is a tenth of a second improvement on your quarter mile time. I think that ratio applies more to heavy muscle cars than our light imports. Our cars are already light so the improvement is less significant. As for brands of parts look at some build threads and google product reviews. You can spend more time writing a post asking about them than actually learning about them by reading.

[cschepp]

Ok so here is what I would do then.... You said you would like to go from the 20 and transfer the parts over to a 25 right? If you do coil packs, all the exhaust side work and leave the intake side alone then you could swap everything over to a series 1 rb25 which has alot of similar parts to the 20.

Now as for reliability I would definitely do these things depending on what you will use this for and such:

-n1 or nismo water pump(200$)
-n1 oil pump(250$)
-oil cooler( not really needed unless your tracking the car(500 new, 250-265 used)
-I would personally grab a set of head studs for the just in case factor
-new thermostat(nismo,65$)
*** now lastly if in maybe a year like you say you buddy will be getting the motor I would say do the head gasket and get him to pay a little but of coin. If you do go spring for a metal one than atleast both you and your buddy know that it won't be bad for when he uses it. Just for your peace of mind when you pass it on. Also something that could benefit you from doing this is to do an inspection on the cylinder walls well you have the head off. There is no point in investing money in a engine that is shot, and possibly give it to your friend.

Anyways that's just a possibility that I threw out there. This would be using your noggin if you ask me. Wish you the best of luck.

And if you seriously wanna save some weight don't had a sound system man. I would say that's prolly 100 pounds on the car! Cf stuff is nice but if you wanted a carbon hood with the Gtr look you would need to really look hard or just convert to a Gtr front end.

[trickey1991]

u can buy just the front facing "plenum" only that bolts to your stock intake mani for the RB20DET on ebay..theyre around 300.00+ shipping .. ive read reviews and suppose they work pretty good and are pretty straight no crookedness in the aluminium

[Skym]

Close to 400whp dynorun with R32 RB20DET (done in Canada, stock intake plenum) -

http://www.youtube.com/watch?v=X_mibuiFSuk

Drifting -

http://www.youtube.com/watch?v=ak1dJrSgJqo&feature=mfu_in_order&list=UL

The short oilpump drive on front of RB20 crank is something I would worry about. There is a way to work around it without rebuilding engine and fitting a aftermarket oilpump drive collar, upgraded oilpump (Nismo oilpump or upgraded gears in N1 oilpump).

Ross external oilpump kit -

http://blog.rossperformanceparts.com/nissan-skyline-external-oil-pump/

[BongRips]

Thanks for that! the reason I'm going to FF plenum is to keep lag down as much as possible as my fmic isn't a turnkey. So are the Nismo and N1 pumps different and if so, is my assumption that the Nismo is better correct?
@Trickey, are you talking about the GSP "plenums" without runners in them like the one in the link?

http://www.ebay.ca/itm/RB20DET-RB20-SKYLINE-R32-TURBO-INTAKE-MANIFOLD-PLENUM-/160639716310?pt=Motors_Car_Truck_Parts_Accessories&hash=item2566df8bd6

Honestly, I'd rather spend a bit more cash and get one that has the runners in it like this:

http://www.ebay.ca/itm/230476429810?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

For a G you get a nicer plenum with runners inside, the water line, 90mm TB, and fuel rail. I think it's a better deal but I don't know really

[M13]

Do some more reading on this matter (via search) before tackling this, I've laid out what's needed.

I have a 20 that does 360RWHP @ only 16PSI and reliably. (just did comp test after 2 yrs and it's 142PSI all across, keep in mind I have 264 duration cams which lower some compression)

400RWHP would be easy to squeeze with a few more lb of boost, but I believe the transmission won't be able to take more reliably. These engines can take 450RWHP (500BHP) with a good tune and supporting mods, the weakest link is the puny 20 tranny.

The key to reliability is well-budgeted supporting mods. Anyone can turn up boost on a stock motor and try to make power, but it takes patience and knowledge to keep one running for more than a few months.

[BongRips]

well i don't think i'll need to boost any higher as i've seen dynos of a couple cars running these turbos at 16psi (highest efficient psi) making 392 and 395 rwhp (posted in a different forum) and that's close enough to 400 for me. but i definitely am worried about the tranny. and i'm pretty sure 450whp is over 500bhp (basing from 15% power loss to drivetrain) because 400whp is around 470bhp. it's good to know the 20s can handle that though as i've heard varying responses from 300whp-400whp being the limit for stock internals, some say higher too.

[M13]

well i don't think i'll need to boost any higher as i've seen dynos of a couple cars running these turbos at 16psi (highest efficient psi) making 392 and 395 rwhp (posted in a different forum) and that's close enough to 400 for me. but i definitely am worried about the tranny. and i'm pretty sure 450whp is over 500bhp (basing from 15% power loss to drivetrain) because 400whp is around 470bhp. it's good to know the 20s can handle that though as i've heard varying responses from 300whp-400whp being the limit for stock internals, some say higher too.

The 20 block is very sturdy compared to a 26 as long as you do all the necessary maintenance and supporting mods.

A tune is also vital as a bad detonation can shatter fully forged internals.

[Skym]

N1 oilpump has bad metallurgy on the gears which are known to crack when used on racetrack. There are upgraded gears you can buy for N1 oilpump with better metallurgy and I gather is what they run in N1, Group-A engines. As far as I know, they rebrand a N1 oilpump with upgraded gears a Nismo oilpump. The Tomei, JUN, etc pumps are said to have better metallurgy with gears than N1 oilpump, N1 oilpump with upgraded gears.

N1 oilpump gear kit -

http://www.rhdjapan.com/reimax-oil-pump-gear-kit-skyline-gt-r-rb26dett-54021

The safe limit for stock GTR pistons (I think stock engine, stock or mild upgrade with turbo's) seems to be 1.2-1.3bar (17.4psi-18.85psi using 14.5psi = 1bar). Anything over 1.4bar (20.3psi) and it cracks block, 3x pistons. I assume that's when leaning on engine with tune hence high cylinder temps.

The fully forged Group-A GTS-R RB20DET last's 3000 hard driven, reliable km between rebuilds (RB26, V8's are the same when driven hard with wetsump setup). From what I can remember, that's with compression into 7's for RB20DET.

That's running up to around 1.7bar, 332rwkw (433whp) for a whole race -

http://www.youtube.com/watch?v=7fEGXNJgfHg

Oh, I meant to ask you M13 (also helps OP), your using the Deatchwerks injectors with new set of stock RB20DET injector O rings???

The biggest problem I've noticed with trans is rear wheels hooking up (drag slicks or semi slicks) and putting excessive strain on drivetrain. If rear wheels spin, shouldn't be a major problem as there is less stress on drivetrain.

[BongRips]

So I should be my internals should all be good then eh? And yea I know a tune is crucial. That's why I'm opting for the Haltech ecu as I've heard the "auto-tune" feature is pretty damn reliable on it and most people don't need to tweak anything once that's set. I will probably be running g-force drag radials. Should I do head gasket and head studs or should I be ok? I've already started pricing things and choosing brands but all I need now is to choose an fpr. Including the bycas kit to lighten up and stiffen up the back end. Also, what is the oem coil pack bracket made of I can't find out anywhere. And for $100 should I replace it with a lightweight alloy bracket with the yellow jackets since they are like $200 cheaper than splitfires for the same performance

[Skym]

Lowering compression into 7's helps with reliability and amount of boost you can run with stock or aftermarket pistons. I noticed one person swapped to 2mm? HKS? headgasket to drop compression into 7's with stock RB20DET bottomend and had mild 256 duration cams (400hp at engine). But the lower compression affect's off boost performance. Normally you use a 1.2mm (stock thickness) Tomei metal headgasket, correct ARP head studs.

Headgasket thickness and how it affects compression with stock pistons -

http://www.tomei-p.co.jp/_2003web-catalogue/e105_RB20_gasket.html

Some aftermarket ECU's now have auto-tune for fuelmaps and stock ECU does with tuning software. It's not just fuel, but ignition that needs to be adjusted to suit changes in fueling and can't see the result's of adjustments to ignition timing (power, torque curves) without a dyno. Also with auto-tune you need to know the A/F ratio's to input into cells on auto-tune map.

If running drag radials, rwd GTR gearbox (cut off transfer case, weld plate over hole), GTR propshaft, GTR differential (subframe, diffhead, driveshaft's, brakes, rear shocks) from a crashed R32 GTR.

Coilpack mounting bracket looks like aluminium to me, as is light grey looking.