Help me. Need to rebuild rb20

[Rb20detboy]

hey everyone. i'm still a little new to the forums just lurking around taking in all the info. ALL INFO IS APPRECIATED!

basically I blew my headgasket on my rb20det out of a 94 skyline in my 240 and want to repair the head gasket. I turned off the car right away. I found there was rust in my radiator and i'm guessing that's the culprit and considering the radiator is from a stock 240 motor. I just need to know what else I should do to ensure the car will be running properly after I'm done. if anyone is familiar with this kind of job I really appreciate your input. i'm trying to keep costs minimal. so far my part list is

new radiator
full gasket set
resurface head
new water pump and timing belt with timing belt tensioner
oil and oil filter
coolant change
spark plugs (copper bcpr6es-11)

I also want to upgrade my turbo while i'm at it to the hks 2530 if anyone has some hookups on that let me know

[fliprayzin240sx]

Just get a cheapie T3/T4 turbo...should be good enough to get you close if not over 400hp.

[Rb20detboy]

is t3/t4 turbos a direct bolt on to the rb20?? and i'm keeping stock internals. any tips on what else i'd need for the head gasket job? thanks!

[fliprayzin240sx]

RB20s are T3 flanged just like VG30DETTs.

But honestly, fuck RB20s, get an RB25DET...

[SmogSUX]

You won't make huge power out of the RB20, but since you've already got it you've pretty much passed the point of no return lol. But yeah find a REALLY good radiator. DO NOT cheap out on that with the RB in an S-Chassis. The RB motors produce a ton of heat crammed in your engine bay. ^Doubt you'd make 400 hp like he said, but who knows? T3 flange try out the Holset HX35. It's a decent sized T3 turbo. If you have the fuel for it and ems go for it. If you're running stock ems you really shouldn't upgrade the turbo..unless it's slightly bigger.

[Rb20detboy]

I wish I wouldve started off with the rb25 instead but didn't have enough cash. I got the rb20 in there so just working on that for now. In the future i'll sell it and move up to something bigger and better. for now the rb keeps a smile on my face. so i can get a t3/t4 turbo and bolt it right up with the t3 flange. sounds good. any recommendations on upgrading any of the lines

[Rb20detboy]

yeah i'm upgrading the radiator to the biggest I can fit in the bay lol. i'm happy with anything over 300hp. fuel wise the only upgrade i have is walbro 255 pump and nismo FPR. I wanted to stick to the hks 2530 because most people say its just plug and play with the rb motors.

[SmogSUX]

...so you have no piggy back or ems? If that's the case I'd recommend waiting until you buy an RB25 down the road and get a PFC for that.

[Rb20detboy]

I was planning on just getting these mods and tuning my ECU or buying a tomei ECU

[DJDANGER24]

i ran a 2530 in my old RB20, made 320ps in Okinawa. That was a 1.2 bar with a blitz ecu. but if you want, i got a 60-1 that you can slap on that RB20. with a good ems and fuel you can net around 400

[Rb20detboy]

what exactly is ems? and how do I go about installing and tuning it? i'm interested in the 60-1 turbo you got. how much you looking to get. what brand is it.

I think this turbo is going a little off topic lol. I'm mainly looking for more info on my head gasket job. I need to know if I should check anything else out. I don't want to put all this back together and find a rod knock or something lol.

[SmogSUX]

Engine management...like Power FC, Nistune, etc etc..


But yeah with the head gasket:


Inspect the valves. If you see any burning or w/e you may need the valve seats ground and have to do a valve job. My 240s head had a tiny bit on it, but I ignored it since it's a budget project (I've got under 1k into the whole car and motor lol)

Other than that make sure u torque stuff in the correct order and use a torque wrench.

[Rb20detboy]

how much do valve jobs usually run for? the main thing i was worried about is that the bushings would be damaged inside the engine. would it be smarter to get a power FC or just tune the stock rb ECU

[SmogSUX]

Not sure...with my old S30 I was gonna go RB25 and Power FC..don't think they offer Power FC for the RB20 though. and they cost around $700.

You'd have to ask the machine shop about the valve job...just resurfacing the head cost me $50.

[Rb20detboy]

cool thanks for all the help.

[Rb20detboy]

what do you guys think about this radiator? CXRacing Aluminum Radiator 240SX S13 KA24 CA18DET RB20 : eBay Motors (item 250577582734 end time Feb-21-10 17:15:00 PST)

[eklips3]

your not alone with rebuilding RB20's my friend !

parts are a little bit of a bitch to obtain but its nothing too bad if you know how to google.

for a radiator i bought a Mishimoto radiator, best bang for buck.
My input for a head gasket is tomei. dont cheap otu by buying a cometic ... i've heard too many horror stories. so yeah your going to spend a few extra bucks for a tomei head gasket but rest assured you'll blow somthing else before the head gasket.

if you want to make this motor able to take a hell of a beating, replace your head studs , main studs and most importantly the connecting rod bolts with ARP hardware.

replacing the bearings isint a bad idea as well. ACL bearings are the best you can buy.

im gonna say this right now as well , if you are going to get your head re-surfaced and your going to strip the motor down to a bare block.. might as well re-surface the block so you have 2 perfectly flat surfaces to insure absolutley no leaks.

but in the end you have to be prepared to spend a good chunk of change on this .. you dont really want to cheap out or else you'll regret that you did.

[Rb20detboy]

Godspeed claims 40% better cooling over stock while mishimoto claims only about 25%. don't know how much back up they have on the info though. and I'm ordering ARP head bolts but what are the rod bolts for? and how hard is it to replace the bearings? i'm running low on cash flow and need to do only whats necessary for now to get the rb back to daily driving conditions. btw I have a full OEM gasket kit for the whole car so i'm sticking to oem head gasket for now. i'm not going to push the car past 350hp tops.

[foreverdark]

Right now I am running an RB20 with a Megan Radiator with water wetter, a big ass oil cooler, and some strong BMW push fans to keep the motor cool. I drove the shit out of my car at NOS center for 4 hours straight with no overheating once then took a break for about 30 minutes and drove it for 5 more hour straight. Not once did it over heat.

Get a good 2 row or 3 row radiator.
Get a big oil cooler.
Get some strong fans.

[Rb20detboy]

ok how about this radiator. it claims 40% more cooling and includes the two fans I need. GODSPEED SKYLINE R32 RB20 RB25 ALUMINUM RADIATOR W/ FAN : eBay Motors (item 380207833453 end time Feb-24-10 18:13:48 PST)

is it hard to install an oil cooler? how about this 30 ROW OIL COOLER + FILTER RELOCATION KIT RB20 SKYLINE : eBay Motors (item 320459870494 end time Mar-07-10 19:40:58 PST)

also anybody know about how hard it is to install some ACL racing bearings while i'm replacing the head gasket. my mechanic said thats the most sensitive piece that couldve been damaged the most when the car over heated

[brn2slid]

the issue isnt cooling, the issue is longevity, the cheaper radiators dont hold up as well and as long as your higher dollar ones. Depends on what you want really, i believe in buying right, once, instead of cheap and learn your lesson the hard way, wasting the money when you should have bucked up the extra 100

[eklips3]

connecting rod bolts ... they are what connect the rods to the crackshaft they are what fail the most.

to replace your bearings you gotta take out your crank. but if you're doing a build just to get the car back on the road to daily driving then i would suggest to touch nothing in your rotating assembly. but then again if you wanna push 350 hp .. you're playing with fire there buddy you are gonna need bigger then a hks 2535 to obtain that.

as for an oil cooler ... meh you dont have to do it unless you are going to be putting the car on the track a few times. others will say this a an absolutely necessary mod but from my side , you wont be needing it.

[SmogSUX]

Problem with putting a high end headgasket in a non built motor is this:

Instead of the headgasket blowing you end up messing something bigger up lol

[SmogSUX]

Problem with putting a high end headgasket in a non built motor is this:

Instead of the headgasket blowing you end up messing something bigger up lol