rb20det parts and ideas

F

fudi

More Doors 4 whores
hi folks

i am looking at building an rb20det at the moment whats peoples opinions on wheres good to get parts ?

im looking to do a full forged setup with 26dett cams in the head do i have to swap over the 26 valve train as well ?

anyone have any experience of porting and polishing the head ? did it make a noticeable/worthy difference

list of to do kinda looks like this
block chemically and ultrasonically cleaned
have oil ways coated (cant remember what its called speeds up oil return flow?)
crank flywheel and clutch balanced
crank polished
new bearings
forged pistons and rods and all new pins rings and seals
block decked and honed
new pumps
head stripped and cleaned and ported (if worthwhile)
cleaned
rebuild with chosen valve train and cams

anything else to consider
 
Can i ask why you're using an RB20 and not something newer? Do you have an engine in need of rebuild?

It's just the blocks are, at newest, 20 years old now. You would be amazed how easy it is to get a reliable 400whp + mountains of torque out of a NEO RB25DE+T. They are newer engines, flow much better and have a better torque output.
 
What power you after? What you want/expect from the engine? Fuel, revs, power, torque, response, etc.

Seems a mega amount of work to even be considering leaving the head stock on an engine which has a pretty poor flowing head.

That oilway thing sounds a waste of time over just having an oil system that works properly.

RB20 rods are almost as wide as they are tall, I doubt you'd break them.

Putting RB26 (solid lifter) cams in a RB20 seems a total waste of time when more than wild enough RB20 cams exist.

Lot bigger issues with building a good RB not mentioned.
 
port the head, but polishing is not a good idea, rough edges cause turbulence which mixes the air and fuel better. Port matching is one of the best things to do on those heads, like Stavros said, It all depends on what power your after too. Decent turbo too, something like a gt25/30 is pretty awesome on those, or a td05 18g which is what I'm getting for mine. I find 20dets a bit lazy standard and scream for more boost, but iv'e seen stock ones run good power with no issues. Hope this helps.
 
Super short stroke, so nothing worthwhile low down no matter what, but can rev for ever. I had a GT2871 and it was dogshit. Total shite. Don't matter what boost you give it under 4k, it won't be great, and something 2871 size will be dead before a RB20 comes in to its own at high revs.
My 2871 made 15psi boost by the time the proper turbo I put on after was making 5. Despite this, there was more torque at 5psi than there was at 15 with the 2871.

Mine was 470bhp with positive boost from under 3k, mental fast from 4k, and didn't drop power even at 8k, on stock head and cams. Would've been more like 550 according to Greg with cams and more boost.

Shit and underwhelming stock, shit if you get the turbo spec wrong, weapons if you do it right.
 
Really? I imagined they would be quite good, I've got one of those and was going to try it out. What's shit about it dude? I was going to run it on my mines ECU just so I could run more boost for the moment, not worth it?
My mate has an hks gt25/30 and it was sick. Boosted all they way, and on a 25 det too, so I thought they'd be good. Was your with a T3 exhaust housing or modded manifold?
 
Was dogshit. Made 300+ of course, but it was shit. RB20 just felt like an RB20 does normally, bag of wank, despite full boost from the off.

These HKS GT2530s etc seem ok on a RB25 (as anything does when it's 2.5ltr and some boost) until you try a better turbo instead, then you realise a decent thing thats bigger actually gives better performance at all rpm.

Was a manifold adapter to fit it, and a custom downpipe of course. Glad i didn't go to the effort, as it was crap, I hate 2871s and similar turbos, on any engine.
 
You must log in or register to reply here.
Back
Top