1990 240SX hatch RB20

[Dev894]

picking up an RB20 swapped 240SX tomorrow gonna upgrade to the RB25 turbo curious on who can tune it? plan on doing 440cc injectors, only aiming for 250whp something to make it a fun but reliable daily

[Mitec]

If you only want 250 whp, I don't see the point in spending the $$$ to put in an RB25. Put a FMIC, larger turbo (heck, throw an RB25 turbo on) and some used GT-R 480cc injectors and you can get that out of the RB20 without having to buy a custom driveshaft and mounts.

[centralcoaster33]

Either way, he'd like a tuner.

Hey Dev894, Jim Wolf Technology comes to mind. AEM standalone and Nistune can be done by yourself I think. For a local professional tuner, you'll want to share your location. I'd have the title changed to "Engine Tuner Needed, Charlottesville, VA" or something to get better responses.

This thread is a few days old now. Did you get the car? Gonna share any photos?

[MeanGreenS13]

If you only want 250 whp, I don't see the point in spending the $$$ to put in an RB25. Put a FMIC, larger turbo (heck, throw an RB25 turbo on) and some used GT-R 480cc injectors and you can get that out of the RB20 without having to buy a custom driveshaft and mounts.

I actually feel like he was talking about throwing an RB25 turbo on actually. But I would actually think a disco potato GT28RS would be a better choice. You can probably pick them up for a decent price and if I am not mistaken the RB25 stock turbo has a ceramic compressor wheel, no? I think with a GT28RS a set of 550cc injectors and an FMIC with a decent tune that would be a really fun car for not much money.

[Dev894]

some reason I'm not getting notifications when people respond to my threads, I have the car currently sitting out side old engine is out new engine is mainly put together, just waiting on a few things in the mail, clutch waterpump and fuel pressure adapter then I will drop the new engine in once the weather clears up, been fixing a lot of things that the previous owner neglected or just did wrong all together, like putting the adjustable FPR on the inlet side of the fuel

[Dev894]

[Dev894]

https://photos.app.goo.gl/bIII6Vi8VLlErALm2

[Dev894]

forum is kinda weird I guess can't figure out how to post pics so the link is a pic of the car thats saved in my google photos

[flartius]

old engine is out new engine is mainly put together

So did you go rb25 then? Good lookin little hatch you have there.

Whats the plan for this car? Sleeper look, aero?

[Dev894]

old engine is out new engine is mainly put together

So did you go rb25 then? Good lookin little hatch you have there.

Whats the plan for this car? Sleeper look, aero?

its a built RB20 with RB25 Turbo that has HKS Turbine and Wastegate, 79mm pistons Cometic metal headgasket, eagle rods, all ARP hard ware. going sleeper with it

[flartius]

its a built RB20 with RB25 Turbo that has HKS Turbine and Wastegate, 79mm pistons Cometic metal headgasket, eagle rods, all ARP hard ware. going sleeper with it

Very nice, just be mindful that that turbo won't handle much above 10psi with that ceramic wheel. You had mentioned a power goal of 250 whp so I think you will be alright but just something to keep in the back of your mind.

[Dev894]

its a built RB20 with RB25 Turbo that has HKS Turbine and Wastegate, 79mm pistons Cometic metal headgasket, eagle rods, all ARP hard ware. going sleeper with it

Very nice, just be mindful that that turbo won't handle much above 10psi with that ceramic wheel. You had mentioned a power goal of 250 whp so I think you will be alright but just something to keep in the back of your mind.

thoight that was only an issue with the rb20 turbo

[Mitec]

That engine should be quite fun All of the OEM Skyline turbos all had ceramic wheels, I believe (unsure if just turbine or comp. side too). You say you have the RB25 turbo and HKS turbine - I'm not quite sure what you mean.

[Dev894]

That engine should be quite fun All of the OEM Skyline turbos all had ceramic wheels, I believe (unsure if just turbine or comp. side too). You say you have the RB25 turbo and HKS turbine - I'm not quite sure what you mean.

HKS makes an upgrade kit for the rb25 turbo

[Mitec]

That engine should be quite fun All of the OEM Skyline turbos all had ceramic wheels, I believe (unsure if just turbine or comp. side too). You say you have the RB25 turbo and HKS turbine - I'm not quite sure what you mean.

HKS makes an upgrade kit for the rb25 turbo

Hmm, if that kit replaced the original ceramic wheel I think you'd be able to run as much boost as you want. Give the turbo a once over and make sure nothing ceramic is hiding in there, lol

[TreyE]

I have a stock RB20DET with RB25 turbo running about 14lbs of boost. Turbo back exhaust, stock intercooler, intake, and I'm making 248whp/225wtq. Won't be hard at all to achieve with that setup!

[flartius]

I have a stock RB20DET with RB25 turbo running about 14lbs of boost. Turbo back exhaust, stock intercooler, intake, and I'm making 248whp/225wtq. Won't be hard at all to achieve with that setup!

You running 14 pounds on stock injectors? I'm not calling you out or anything I'm genuinely curious if you're having a fuel cut issue.

[ca18det_boy]

I have a stock RB20DET with RB25 turbo running about 14lbs of boost. Turbo back exhaust, stock intercooler, intake, and I'm making 248whp/225wtq. Won't be hard at all to achieve with that setup!

You running 14 pounds on stock injectors? I'm not calling you out or anything I'm genuinely curious if you're having a fuel cut issue.

FWIW, I'm running 12lbs on my stock RB25 turbo. Duty cycle is only seeing 85% at full boost. I would think his injectors would support 14lbs without issues. Granted there's a 100cc difference between the two, but I would still think that he wouldn't max them out quite yet.

[flartius]

Good to know, ATM I am at 10 psi everything stock but wasn't sure how far it could be pushed.

[TreyE]

I have a stock RB20DET with RB25 turbo running about 14lbs of boost. Turbo back exhaust, stock intercooler, intake, and I'm making 248whp/225wtq. Won't be hard at all to achieve with that setup!

You running 14 pounds on stock injectors? I'm not calling you out or anything I'm genuinely curious if you're having a fuel cut issue.

I have 7mgte injectors, very slightly more than stockers for RB20DET.

[Dev894]

You running 14 pounds on stock injectors? I'm not calling you out or anything I'm genuinely curious if you're having a fuel cut issue.

I have 7mgte injectors, very slightly more than stockers for RB20DET.

7mgte injectors direct swaps?

[TreyE]

I have 7mgte injectors, very slightly more than stockers for RB20DET.

7mgte injectors direct swaps?

Sorry, my mistake. They're 7MGE injectors - 315cc. Direct swap. 7MGTE injectors are low imp unlike the 7MGE.

[Dev894]

7mgte injectors direct swaps?

Sorry, my mistake. They're 7MGE injectors - 315cc. Direct swap. 7MGTE injectors are low imp unlike the 7MGE.

So i should be able to get those from autozone or something fairly cheap

[TreyE]

Sorry, my mistake. They're 7MGE injectors - 315cc. Direct swap. 7MGTE injectors are low imp unlike the 7MGE.

So i should be able to get those from autozone or something fairly cheap

I have no idea man, I don't even know why they're in my RB20 to be honest. It came with them, I didn't even notice until I was in there installing my FPR and saw light green. I'd just go with 440's 550's or whatever, they'll be tested and offer more head room for HP. Make sure you have ECU or SAFC though so you can tune for the increase in flow.

[Dev894]

So i should be able to get those from autozone or something fairly cheap

I have no idea man, I don't even know why they're in my RB20 to be honest. It came with them, I didn't even notice until I was in there installing my FPR and saw light green. I'd just go with 440's 550's or whatever, they'll be tested and offer more head room for HP. Make sure you have ECU or SAFC though so you can tune for the increase in flow.

Only looking for 250-300whp which 300cc injectors should be more than enough but if it is cheaper to go with 440s i will

[TreyE]

Idk if I'd trust used ones off eBay so I'd get them cleaned and flow tested if you go that route!