RB20 Cheap turbo upgrade.. few questions

[Cool Hand Luke]

Ok i thought i had my ideas of a good turbo upgrade sorted for my RB20. I was going to go for an RB25 turbo, then leave it like that for a while and upgrade to a hks2530. However now after reading more, ive become not more, but less certian on what i want to do . My hunger for more power is getting strong, but i dont really want to spend $2500 on a new turbo at the moment, so i have a few questions.

At the moment i have these mods:

Pod Filter

Turbo back 3" exhaust, with seperate dump, & gutted cat

550x270x70 PWR FMIC with custom end tanks

Bleed valve

VL Turbo fuel pump

I have an Motec M4 coming (i know its not the best option, however its off my race bike and will only cost me $1000. New it cost around $4000 with upgrades and IEX expander.)

With these mods (motec excluded) what power would i be getting now, and what gain could i get from correct tuning? I havent been to the drags with it so i dont know any et's yet

RB25 Turbo: Seems like the best all round solution, but will only give 15-20rwkw gain over mine, which seems not so exciting . With correct tuning what sort of rwkw can i expect from these? Ive also been told that i could safely run 16psi with it as its feeding a 2l not 2.5, and therefore less stress, is this true?

VG30 Turbo: How much boost can i run with it as it has a steel wheel, and for people who have had one before, when does it really start to pull hard in say 2nd gear? Also will the VG30 turbo fit straight up no other mods required and with good tuning, what sort of max power could i get from it?

TO4E: I read that clint32's RB makes 234rwkw with an TO4E. How much is one of these, how easy is it to get and does it have an external wastegate? I know that some people say it would have terrible lag as its big and plain bearing, but im well aware that a 2l 6 wont be like a BA turbo, nor would i expect it to. When would a turbo like this really pull? I read that clint's made full boost by 4500rpm, would it start pulling hard before or after then?

GCG HI-Flowed RB25: I thought it was a fairly expensive option, as GCG dont have cheap prices, but sydneykid was also saying in a post that 250rwkw is achieveable with this turbo, and the boost wound up. How would this be in terms of lag etc?

Being in a 180sx, what sort of times could i expect if it hooks up with say 200, 230, and 250rwkw. Just so i can get an idea of what difference in performance it makes as i know well and truly that dyno figures can mean not so much in the real world.

[Fast31]

i dyno'd my GTSx yesterday with the following mods

550x300x70 cooler

microtech MT8 computer

3 inch mandrel bent exhaust

13psi

made 161rwkw on the dyno.

My old RB20 setup made 227rwkw, with a TO4 turbo, big injectors, big fuel pump, Haltech computer and 17psi.

was very laggy, the turbo was'nt the best match for the motor, but when it come on boost, hang on tight.

for a drag car it was sweet, but alittle too laggy for a streeter

[Clint32]

The to4 requires and external gate but i mounted mine on the stock manifold to reduce the cost. It pulls hard from under 4k and makes full boost by 4500, when driving normally it pulls hars with no noticable lag. The only time the lag is noticable is when you are just crusing along and you put your foot down you have to change down to get then revs up. But if you are driving hard and keeping the revs up the lag is not noticable.

The highflow is probably the best bet for ease of fitting and drivavbility but you would need a rb25 or vg30 turbo to start with for good results.

With 234rwkw my car has run a 13.4 at 112mph, but i broke the gearbox so i didnt get a decent run, i expect to run a 12 very soon.

[Bl4cK32]

Yer aiming way too high if your trying to get 250kw with an rb20. What sort of power are you trying to end up with? The rb25 stage 2 high flow, ive been told "wont even run on an rb20, it surges then cr*ps itself, makes full boost by 4500 rpm."

[Cool Hand Luke]

What were the specs of your to4, and what price was it?

[Clint32]

0.6 ar comp and exhaust housing, the exhaust wheel was a little big about 59mm from memory, i got it as it was cheap, about $1000 for it all up once i got it recod, cost about $1700 for turbo, wastegate and manifold modifications.

[Fast31]

Clint32

How did you go about welding the wastegate to the standard manifold

[Clint32]

here is a pic if works, pretty simple to make, but needs to be welded on propery cost $200 just to do this.

[rbs13]

wtf aiming too high for 250rwkw on a rb20.. your nuts mate :Djms have their drift 1via making round 250 with rx6 with std internals but good tuning i bet.. but i think that car gets put through utter crap when it gets taken out! i firmly belive that 250 is made pretty easy but it would take care ful tuning to make it reliable. rb's have low compression so it should be alright with taking 1.3-1.4 bar boost with good premium fuel etc.

[Roy]

rbs13, the engine your thinking of had a TD06 Trust trubo. The RX6 one of the turbos on the R33-RB25

[Bl4cK32]

Yeah mate - not all of us have the supply of parts, and spend grands on tuning to squeeze out 250kw out of an rb20. How much money do you think it would cost to get 250 kw out of it -10g?

Now compare it to say an rb30 bottom end with a 25 head. Im told this engine produces the same output as the rb20det with no turbo. 10g compared to say 2g for a rebuilt motor package. Thats what I was trying to say.

[Fast31]

if you can build me a RB 30 bottom end and RB25 head , for two grand and make more than 250 rwkw ill drop the cash over tomorrow

[Bl4cK32]

i didnt say itd make more than 250 , but youd be closer than spendin 10g on an rb20

[Fast31]

ive got 227RWKW out of my RB20, heres how i done it.

Haltech E6K. 2600 fitted and tuned

2nd hand T04, 1000 bucks

3 inch mandrel, 700.

Front mount cooler, i used a truck core cost me nothin but say 2000 for a schmik one.

Series 5 RX7 injectors 500, Bosch motorsports pump, 350

total $7150, if you had to add labour for the fitting of the turbo, pump and the injectors then $8000 would be getting close.

Its not cheap but the Results are worth it

[Bl4cK32]

Exactly. Thanks for sharing man. The rb30/25 will cost you ~2000. Then add a stage 2 gcg 500hp high flow for ~2450. Where now lookin at 260ish rwkw on 15 psi. maybe add a few extra $$ for some parts.

Spendin probably be the same but look at the end results of the two.

[Cool Hand Luke]

Unfortunatley its not as easy as that. For 2 grand, i agree that you could build up an RB30/25. What about the money for installation and removal of the engine, purchace turbo etc Not to mention that this is my daily driver, so the time it needs to be off the road. Also i dont think that will fit in a 180sx. How much taller is the twin cam 30 over a 20? Even with custom engine mounts i can only just clear the bonnet with the intake pipe running over the top. So add another $1000 for a intake, $800 for plumbing.

Im not disagreeing with what you say, but personally i'd rather have an rb20 with 230rwkw than an rb30 with 250. And anyway, i was just asking a few questions about turbos, not engines

[Cool Hand Luke]

There is a TO4E for sale, it says it has an internal wastegate and suits 3SGTE. Are they all TO4E's the same?

[Roy]

The RB25/30 will cost more then 2 grand wont it. How much are you expecting to pay for the head, the block with internals, the drilling and tapping for timing chain, machining to ensure you end up with the right compression ratio, labour to remove and reinstall, cost of new gaskets, etc etc.

A new timimg belt, new water pump, and associated bearing and idler pulleys will cost inthe vicinity of $500, or did i pay too much at my 100,000km service.

I never thought the RB25/30 setup is anywhere near that cheap.

[Bl4cK32]

sorry dudes but your wrong. Im currently doing the above with help from a colleague, so there is no labour costs. And yes it is cotsing 2k for the engine. 770 for rebuilt rb30 block, 750 for rb25 head. then its 500 for any left overs. The cost of the turbo is ~2450.

Yes the height is ~30mm taller.

Now, forget what I said about the damn engine and go back to my original comment. The Rb25 high flow wont run on an rb20!

[Cool Hand Luke]

a wrecker up here has a vg30 turbo off a single turbo vg30? Is this right, or a different one? I always thought they were twins? I remember reading one has a ceramic and one a steel wheel? If so what are the boost differences between them?