rb20det: turbos/ limits/flaws

[lexcrob]

Ive been reseaching for a good turbo to bolt up to my rb20det but seems some information is conflicting.

300zx turbo
rb25 turbo
hx35
hy35
percission 6031e / 5431e?
hks GT-RS

Its not my daily driver just a sunday driver that I bring to the drag strip. I dont see the point of spending that much money to get a ball bearing hks since it will never see an autocross. I dont have the funding to go forged pistons, crank collar or any kind of high dollar fuel management. Ive been trying to seach and follow others builds but it seems most ditch the rb20 in favor of the 25 but I happen to have 2 pretty much for free. So I figure ill just go for a mild reliable set up. Im pretty convinced on going the carlH tune route and want as much power as I can make.

Maybe point me too a some builds I can model on? Or recommend a set up to "max out an rb20" with a budget in mind. (i can fabricate and have a professional fabricator/welder buddy so thats not big deal)


My favorite build ive seen was the guy that welded two t3 1inch flanges to the stock manifold and put some holset?
I was thinking buy a egay and have my fabricator beef it up a bunch and work it for fitment a bit.?

[lexcrob]

Can anyone explain what the heck happens to the oil pump beyond 400hp? I just dont get why or how the oil pump self detonates......revs up to fast from making so much more power and hydrolocks??? crankshaft distortion?

Or why this engine has this daunting oil control problem where to much in the head what not. Why not just pull the pump apart and shim or cut spring accordingly like scca ka24de guys do? Or increase sump compacity? I loved the guy that put an external oil pump but thats just scary if it broke or jumped teeth ingenius but id rather explore other options.

Ive never seen or heard of that on any other engine. Normally its ring lands or rod bearings or maybe just blow a hole in a piston. Not o crap the oil pump spit in half.......

[Yellow4g63]

If you rev it too far it the crank will slip on the oil pump drive. This happens to all the Older RB's. I think the 34's nissan fixed that problem. The fix it to put a new collar on the crank so it won't slip. According to CarlH and a few other they reved their RB20's to 8500 on the stock springs so it should be fine. Get a Nistune Realtime board, A Z32 maf, 550 or bigger injectors, T3/T4E 50trim or what ever turbo. Just tune it and enjoy.

[lovehateRBrelations]

RB20's really respond well the borg warner s256 turbo. Ive used those one rb20's and they spool pretty quick but can flow big power. honestly tho the cheapest option and will still get u a snappy turbo that makes a lot of power is to get a RB25 oem turbo and have it high flowed and rebuilt. We have used this set up and even used the stock turbo manifold and it will flow up to 400ish hp. Other really good turbos to look at the borg warner efr series,GT2871r, precision, which i dont know a lot about personally but i know they make an excellent product. HKS GT-RS imo is very expensive for what it is, but is a quality piece. Turbonetics t3/t4 hybrid is also a nice turbo for the money. I dont know how it specifically runs on a RB20 (but i know lots of ppl use em), however We built a sentra spec v using that turbo on a qr25 fou banger and it made close to 400hp. If you really go any bigger that the turbos already mentioned you'll be in lag city since Rb20 is obv only a 2.0L engine.

[Yellow4g63]

lOl I'm in lag city with my SC61 but I'll just rev it little higher lol.

[lexcrob]

Where could i send say a rb20det turbo to get "high flowed".

I have two stock rb20det turbos that build boost and oil seals arent blown so maybe I can work with them?

[Carl H]

dont waste your time trying to modify a stock turbo...it will only blow up in the end.
2871 is a sweet turbo on the 20.
hx35 on a 20 looks something like this :
at around 16psi.
laaaaaaag monster.

[lexcrob]

That looks like perfect size for power im going for but yep lag city.......

I did find this one rb25det NEO turbo? turbine wheel looks to be steel? 750$ oem nissan sounds too good be true?

http://www.nissanraceshop.com/product/3 ... nQodhyAAZg

Im just gonna drag the thing down the 1/8mile anyways....

hx35 is looking like an option ..........

http://www.thedsmgraveyard.com/product_ ... %20bep.htm

ISIS ? I know a ton of guys around town running ebay and their still running been a year for most of them
The two guys that werent lucky the oil seals just blew out and no big deal really smoke smoke limp home.

http://www.enjukuracing.com/products/*I ... 20DET.html

[lexcrob]

Carl what kind of fuel management was that dyno sheet running im curious! Finnally sold one of my other 240's so got a little money might be able to start building this rocket.

[Carl H]

stock ecu...spent a day with that car on the dyno.
could have made more power but lifters were ticking something nasty so we stopped for the day.
20psi would have seen it well into 300's.

[lexcrob]

injector size ? just a walbro in the tank? stock rb maf and everything else?

[Carl H]

walbro, silly large 880cc injectors and z maf along with my tune...total overkill for the setup.
dude needs to downgrade to a 2871r and he'll make about the same power with 2krpm wider powerband.

[Yellow4g63]

Carl is he peaking @ 6500? or was the pull just stopped at that point?

[Carl H]

no, forgot to rescale the rpm scale for 8500 but was revving to 8.

[lexcrob]

http://www.redz31.net/turbofaq/dyno.graphs.html

^seems vg30det turbo can handle 18psi 300hp ball park

http://www.nissansilvia.com/forums/inde ... opic=25176

^these guys say its bigger than rb25det turbo

My concern is if it comes apart like rb20 and rb25 turbos......
Now if i can just find one for sale......proving to be difficult.

[Yellow4g63]

Why not just get the 2871 PTE sells a version too just like the garret. A Z31 turbo sounds like a huge pain in the a** to find because of the age. and if you do find one your better off getting it rebuilt before you even bother to bolt it on. Spend a little extra coin and get a new turbo.

[lexcrob]

http://www.skylinesaustralia.com/forums ... e__st__300

hypergear expensive but looking more like what im shooting for 1300$ sounds better than 1700$..

[Yellow4g63]

ATP sells the 2871 for 1400

[lexcrob]

hmm!

[Yellow4g63]

also Raw has a billet turbo I think for the RB25, they need a core with purchase but it should be cheaper and a easier bolt on.

[lexcrob]

raw didnt have a listing for billet?

Ill start a thread of the build here soon. Hopefully I get some time this weekend to get other motor pulled.

[Yellow4g63]

Callem Ricky knows the down low

[klh6686]

If you rev it too far it the crank will slip on the oil pump drive. This happens to all the Older RB's. I think the 34's nissan fixed that problem. The fix it to put a new collar on the crank so it won't slip. According to CarlH and a few other they reved their RB20's to 8500 on the stock springs so it should be fine. Get a Nistune Realtime board, A Z32 maf, 550 or bigger injectors, T3/T4E 50trim or what ever turbo. Just tune it and enjoy.

Just wanted to point out that it's not safe to assume you have the fixed oil pump drive unless you check it.

My best friend's R34 neo engine had the faulty oil pump drive, I took the motor apart with him.

I'm not sure if it was an early neo or what, but it's certainly a neo (solid lifters, traction control TB, plastic upper timing cover etc etc)

[Carl H]

only the 26 recieved the updated crank from late r32 builds on...everyone else got left in the cold.