How to turbo your N/A

[666DAN]

Update: New 70mm exhaust made a massive difference, helped with flatspots in the power curve. High-flow cat and dump pipe still to come.....then one day I'll have a FINAL dyno result.

[dondesoto]

Have you ever taken it to the drags 1/4 mile time would be interesting .

Your high compression turbo set really interests me . My rb30 has an r33 rb25de head , using the rb25de pistons gives me 10.5 compression . a boost of 5 psi would equel a 7 psi boost at 10.0 compression . I,m part the way there in that i,m allready using rb25det injectors and have bosch 040 fuel pump , and i,ve got a rb25det exhaust manifold sitting under the workbench . So really i just need a turbo , oil and water lines and intake and exhaust pipes . Currently i,m using a 68 mm xf falcon t/b , and the afm is the same they use on stock rb25det .

I still have to sort out a fuel starvation prob i had when running at lake gairdner speed trials , need bigger fuel lines and maybe a swirl pot . I,m also using the stock rb25de ecu with an safc 2 .

[666DAN]

Funny you should mention the starvation, would have though that setup would be fine...even for a turbo???

No 1/4 mile times yet...even though the others guys are calling me weak for not taking it down to Willowbank

We'll have to talk RB30's soon, I'm looking at building an RB30DET Neo, so you may be able to give me some guidance!

[Turbine]

Hello Skylines Australia. I have an interesting subject i would like to chat about.

My project is to produce as much power out of the RB20 engine with the least amount of effort, meaning i want it to breath easily.

I have a couple of things i want keep constant though, for now at least.

8000RPM rev limit

standard crank rods and pistons

Aftermarket exhaust manifold

Modified stock intake

I would like the torque curve to start its climb upwards at right on 4800RPM. At least be well on it's way upwards. Before this speed I'm not interested in making grunt.

This engine has an Autronic SMC ECU attached to it, is a 3 speed automatic with a trans brake - Drag use only.

Their is also another important thing about it, it's a normally aspirated engine that i wish to run boost in.

Sounds impossible??? I think not

I have plans to upgrade the bottom end and the head, but for the moment all I want to do is run this settup with the propper turbo, injectors, intercooler and things like this.

I do have a goal of 450-500BHP, so i need to know from you guys what sort of turbo I'd need to run that sort of power. But if I get responses of numbers of models of turbos I'm lost, I have very little knowledge of what a gt30/gt40 has to offer in the way of airflow capacity under boost.

I'm looking for something different, the right combination of parts to run low boost levels but with massive AIRFLOW in mind.

Like an RB20 that kicks a 25's butt.

I'm sure somebody would like to see that

Thanks guys

Turbine.

[paulr33]

hi turbine,

you should look at doing an rb30 bottom end conversion. if you do use the stock rb20 block it will be ok youll have to tuffen it up a little and the gt30 on rb20 will be laggy as all hell, forget gt40 its way too big. check out threads in forced induction titled "top rb20 260rwkw club" see what configs they are running and check out the rb30 bottom end thread as well. can be done for about $5k but then you need turbo and other associated stuff with it so 10k at least. the 25t has more torque, better turbo and better airflow. does the smc communicate with the auto box or is it a non auto based ecu?

[Turbine]

Hello paulr33

The SMC is a standalone ECU, almost the altimate engine management system.

I'm not realy interested in the RB30 bottom end just yet. It's easy horsepower that way.

When you say about the gt40 turbo being laggy, thats good if it is laggy below 4800RPM because it's a drag car, I dont intend to have midrange power, I'm aiming for top end high revving horsepower. So will the gt40 be good at 5000RPM to 8000RPM?

[paulr33]

yes i understand what the smc is, does it have support for auto or is it a manual only ecu? what happens during gearchanges? does it have logic for automatic gear changing or does it just keep the throttle nailed. the gt40 is on the xr6turbos 4 litre so it should be mega laggy on an rb20

[Turbine]

Yeh you can use some of the auxilary outputs for solenoids both on off and modulating, but as far as controlling gear changes I'm not sure.

It wasnt what i intended to do with it.

[paulr33]

you should find out how your ecu handles the autobox cos at the power rating it will fry the gearbox and give it all kinds of hell. if your stuck with smc and it doesnt support the auto (as in has no logic for gearchanges) then change to a mechnical autobox. only electronic autoboxes will get fried and a mechanical one is fine

[Turbine]

Gearbox is good for 450kw engine (reliably), has a transbrake and high-stall converter, full manual operation.

If you are just interested in drag racing, their is no need for gearbox logic really, just do trial runs at different RPM's and watch what happens to th E.T and MPH.

Circuit cars, well thats a different ball game.

[gatty]

i think what he's saying is that like with the 33's there is no ECU out there for the auto box - which means it doesn't changes gears at optimum times and other crazy shit like that...

[Denzo_GTR]

Okay just a thought but why wouldnt it be better getting a Engine Implant or just saving up for a GTS-T or a GTR. . . I mean doing it your self i just dont think you would be worth all the trouble. Look i know you may be cheaper to convert the skyline yourself but i dont know the timeline comes into. My mate got his Skyline GTS converted and it took him over 6 months to finally do everything. . . thatz souceing parts. . getting them installed. . tuning. . . geting conversion correct. . . and itz not a simple wack it on and it will go. . .itz alot tougher than most people think. . .

[Gung-Ho!]

Ok, search forum was a no go for info. so.....i'll try here.

Can all the turbo bits from an RB20DET simply bolt onto the RB25DE? I found a great donor car and want to try it if it'll work. I don't plan on using more then the stock boost (or just slightly more) and only want to touch the 230-40HP range. More is nice, but if not then as close I can get will do.

[gatty]

you could use the rb20 stock turbo i guess - but not manifold etc - you'd be bess getting stock rb25 bits mate

[Squizz]

Exhaust manifold is the same for 20/25

[meggala]

interesting thread 666dan still waiting for a power figure from your car?

I have a cefiro with an rb 25 defrom and r32 I will be considering the turbo route over the next 12 months. jsut deciding if I want it or not.

from memory crooser had this set up for 2 years or so then pulled the otor and checked it and the was no additional wear.

meggala

[sindows]

If i get the RB25DET and the GTST Brakes and possibly suspension, will i need to change my 5 spd manual gearbox?

[gatty]

http://www.skylinesaustralia.com/forums/sh...196#post1360196

check out there dan - what you think bout that idea?

[666DAN]

Yeah gatty that's a better idea, that's the way all of the GReddy bolt-on kits work....forgot to mention it!

If you do a search you'll easily be able to find installation instructions for the RX-8 or 350Z kit, go by what they do.

[gatty]

sounds sweet - i am considering doing all of it myself - helping a mate fit a new turbo to his - it doesn';t seem to be all 'that' different