New engine questions, - sydneykid?

[Cool Hand Luke]

Ok, im going to change engines on my car, from what ive read i have a few options, can anyone answer these questions:

RB24 - I have a RB20 at the moment. How much would it be to build it into a 24. I have an R34 GTST turbo, what sort of power outputs would be expected, and what sort of ecu mods would be needed? This would be my first pref it could be done for under $4000, but maybee im going to be laughed at for that. Also a aftermarket turbo could be budgeted. How are they for torque? Ive heard they would be happy to rev to 9000rpm?? I guess the only bad thing about this is that i have to buy a 25 gearbox and that will cost alot...

RB25 - How many RWKW would i expect with FMIC, POD, turbo back exhaust? I want more than my 20 has

RB30DET - The main problem here is clearance issues.. How much higher is it than an RB25?

[Roy]

Whilst using the R34 turbo, id say stick with the RB20 and stock internals. An RB24/25/30 isnt going to really shine unless used with a larger turbo.

What are you wanting to do with your car once its finished???

That should have a large impact on the course you choose. If you just want to go a little bit quicker then id say a slightly bigger turbo that can reliably run 1.2bat with std RB20.

... and you have PM

[Cubes]

I've driven around on low boost (10psi) as of late for a whole tank.

Flicking to high boost made the car feel fast again. The RB20DET really does like that extra 5psi of boost its amasing the difference it makes.

[rb25]

I'm not sure about the cost of upping it to 2.4L. I'd imagine you'd de-stroke an RB25 crank, or stroke an RB20, but it might be too much of a reach for the RB20 crank, and i'm not sure about what rods you'd need to use as well....

The RB30 block is about 25mm higher than the RB25.

If your using the stock R32 GTSt ECU I guess a remap would be fine for most combinations.

I would go for something very revvy and responsive:

1) Hi-flow the R34 turbo

2) re-map the ECU

3) fuel system

thats if the drivetrain and handling is all good.

-rb25

[R31 POWER]

Joel how are you making 10psi on low boost,coz the lowest I can get is 12psi and thats with no bleed valve.

[Cubes]

Its 10.9 psi.

And thats according to the digital readout on the Blitz SBC-iD read out.

When I had the bleeder in there, the stock boost setting was 12psi, the restrictor bumped it up a little.

1psi is not anything to worry about maybe my EBC reads boost incorrect slightly or your guage reads boost incorrectly.

[Cubes]

Its 10.9 psi.

And thats according to the digital readout on the Blitz SBC-iD.

When I had the bleeder in there, the stock boost setting was 12psi, the restrictor bumped it up a little.

The EBC reads boost exactly to the .1 as the Dyno Dynamics Dyno at RPM.

What boost guage are you running? 1 psi is nothing to worry about.

With the stock exhaust etc it made 115rwkw dead stock on 8psi.

With the AF's around 12:1 on 8psi it made 125rwkw.

Exhaust fitted and boost bleed it made 152rwkw on 12.5psi.

FMIC fitted and still 12.5psi it made 155rwkw.

EBC and 1bar it made 164rwkw.

The dump pipe isn't really the best as it has a V shape smack in front of the exhaust wheel.

The 3" pipe they used obviously wasn't stretched enough/properly.

That will be going soon.

[Cool Hand Luke]

The reason i wanted to change engines is because my 20 gearbox blew up, and it will only do it again. I could buy the TD06 and a 25 gearbox but that would cost around $5000, plus ecu mods. I figured if i bought a 25, it comes with the gearbox and a bit more top end, and a fair bit more midrange..

I could afford a 26, but how much could i sell the 4wd gearbox for?

[Sydneykid]

Hi Luke, here's what I would do with your budget;

1. Ball bearing hi flow the R34GTT turbo $1.8K

2. Split dump and engine pipe $0.5K

3. Adjustable camshaft pulleys $0.4K

4. Chip R32GTST ECU inc dyno $0.8K

5. R33 GTST gearbox $1.0K

6. If you don't have a FMIC then a standard R32/33 GTR intercooler is the go with alloy pipework $0.9K

6. If you haven't already upgraded the fuel pump, then a standard Z32TT or R32/33 GTR fuel pump is the go. $0.3K

7. You will need an adjustable fuel pressure regulator to stretch the standard injectors $0.3K

For a total around $6K that will give you 200 to 220 rwkw at 1.3 bar depending on the tuner and your engine condition. All the bits are transferable to an RB25DET later on should you want more.

You can make a 2.3 litre out of an RB20 by using a RB25 crank and 4AGZE pistons. To get to 2.4 litres you use an RB26 crank. JOnJOn has done this sort of stuff to an RB20, look up his posts.

For reference, an RB30/RB25DET is 38 mm taller than a RB25DET.

Hope that helps.

[Cool Hand Luke]

Thanks sydneykid, helps alot.

As normal, ive thought of something better. If i bought a 26, how much could i sell the 4wd gearbox for? If i buy the right car i can get one.

The way i want to do this is actually pretty complex, but another 180 im looking at has a kevin kent SR that has 310rwkw. I could sell that engine and buy a 26 with change left over...

I was going to fix the few dents on my car and sell it, as i can get as much for this as i could buy the above 180, plus it has already got tein suspension and full roll cage etc which mine doesnt. All this works out fine with the RB26, as long as i can sell the 4wd gearbox for a reasonable price.. ala 1500ish. So i would have maybee 6-8000 for an engine conversion if anyone has any other suggestions, it just has to be a 6cyl. 2JZ?

[Sydneykid]

Hi Luke, you will still need an RB25DET gearbox and your not going to get 310 rwkw out of a standard RB26DETT. A good RB26DETT complete ready to run is going to cost $6K, plus $1K for the gearbox, $1K to fit, $1K for the radiator, $1k for the oil cooler and remote filter, $1.5K for the clutch, then what ECU are you going to run?

Lat time I costed an RB26DETT conversion there was no change out of $12K with not much more than standard power.

This is a Skyline forum so lets kill the 2JZ idea, the turbo/turbos is/are on the brake master cylinder side. This not good in a small engine bay.

[rb25]

yeah - the 2jz-gte has the intake on the opposite side to nissan 6cyl. engines - forget it, nightmare

[Cool Hand Luke]

I know that i wont get 310rwkw, but im not fussed if its less. it makes 310rwkw on avgas/tolulene, 260rwkw on pump fuel, but even still, i want something different and a sr 180 is common .

In terms of the RB26 install i can get an engine/gearbox for $4500

RB25 gearbox for $1400

Got radiator

Sell the 4wd gearbox for how much?

Why oil cooler and remote filter?

$1000 for fit

Not sure if i would need a twin plate clutch especially being 2wd?

It comes with std ecu

Or could i build a tough RB25 for the same money?

What i want is the RB?? in the 180, because its different, light and i like 6cyl turbo the most out of any engines. Dont know what i could sell that comeplete SR, but i would have thought $8000-10000 with everything, ecu turbos etc, so that would be my budget plus a bit more. In terms of power, i want something reliable, 260rwkw or so, and able to be abused sometimes without worrying about exploding.

[Sydneykid]

Hi Luke, let's dismiss the light stuff straight away. Our 1990 R32GTST with the RB31DET in it, is lighter (1140 gs) than the 1994 SIL80 (1160 kgs) with the RB25DET in it. People compare S13's with R33's or R32 GTR's and they are lighter, but not R32 GTST's. I have won heaps of bottles of Jack with bets on which is lighter.

Moving onto your questions;

"In terms of the RB26 install i can get an engine/gearbox for $4500"

I have never seen them that cheap, a running RB26DETT is worth $6K on its own.

"RB25 gearbox for $1400 "

Last one I bought cost me $1.1K. Plus you will need a tailshaft and a speedo drive conversion.

"Why oil cooler and remote filter?

The S13 engine bay is much smaller than a Skyline and there is not as much air moving around the engine. A remote filter and oil cooler is a must for 300 rwkw.

"Not sure if i would need a twin plate clutch especially being 2wd?"

We use a twin plate in 2wd's and a triple/quad plate in 4wd's.

"$1000 for fit"

Tell me if you can find someone good who will do it cheaper and I'll use them. Wiring harness, fuel lines, water hoses, brake and clutch hoses, engine and gearbox subframes, instrument calibration, air con hoses, power steering hoses and reservoir, electric fan and wiring, intercooler pipework etc etc

"It comes with std ecu"

If it's an R32 RB26DETT then that's OK, if it's an R33 or R34 RB26DETT then it's not chippable and you will need a PFC or similar.

As I said it's a $12K job, ask around and see if anyone has done it all up for cheaper.

Hope that clarifies my position further

[Cubes]

Why not just buy a 32?

With the type of engine conversion you are looking at there is definately the insurance problem.

Sure it may be different which really it isn't as slapping the RB20/25 in to a 180sx has been done quite a few times.

Tim Possingham at RPM has also done this conversion in a car he did up then sold as he does.

If you like the smaller car i'd say go the 32 GTST and turn it in to a bit of a track car with a 25t g/box rb25 or rb30.

[Cool Hand Luke]

Ok absolutley, thats why im asking on here, because i dont know and the people on this forum do

To change the topic a bit then, back onto the 25, with say cam gears, turbo, ecu, fmic, exhaust etc what can be reliably run with them?

[Cubes]

max 250rwkw with a good tune and turbo.

Stock turbo max is around 190-200rwkw on 14psi. I havn't seen any of those 200rwkw on 14psi die yet.. i.e freebaggin & Gregpin's.

[Roy]

In QLD what is the legislation concerning weight vs cc for registration? That might be another hurdle if wanting to use an RB26 or bigger in an S13.

If you want something different throw a 20B in the S13. I cant see the engine being bigger then any of the RBs and they like to rev and like big turbos and knock out healthy power figures.

Std for the factory the 20B has more torque then the RB26, and is cheaper! A 20B S13... is very different.

[Cubes]

That would definately be different. I vote the 20B.

I've got an old 82 Mazda 626 sitting unregistered in the driveway incase the skyline blows something. 20B in that thing would be fun. I've seen VN V6's in them. Would be a good traffic light warrior with a supercharged V6 in it..

[Clint32]

Sydneykid what have you removed from the 32 to get the weight down, eventually i was hoping to get mine down to around 1100kg, i assure yours is a race car so it has only a single seat and had a cage and youvve remove hicas, a/c, heater all interior.