Rb25 Turbo Onto Rb20det

[WazR32GTSt]

i'd love to take you up on that offer, gordon, but i am unfortunately going to perth for the weekend and i leave tomorrow morning!

no boost until 3500rpm?? or full boost at 3500rpm?? The guy i spoke to said it would lag by about 500rpm more than the rb20 turbo

maybe i should be looking at intalling an exhaust cam gear at the same time.. i want to keep the car drivable, after all, as its a daily driver..

hmmm exhaust cam gear (maybe $150), plus labout maybe an hour ($70), then tuning ($100). its not so cheap, but if i'm going to do it i might as well do it properly...

but then if i go down this path, i really ought to be looking at ECU and fuel pump. i've already got some sort of chipped ECU in there but it runs way too rich. will the fuel pump hold up ok with just an rb25 turbo?

so many questions..! sorry..

[predator]

hmm, damn, i was feeling bored too

well its about fullboost by about 3800 I remembered (as measured on safc).. it starts before that, but its pretty snappy.. i.e.. nothing nothing... ON

But there were things I did think to reduce that (like you say).. cam gears, cams, different stall speed, proper aftermarket ecu that can handle auto, etc.. but you know it all adds up into an expensive proposition.

I went to a GTR pump and nismo FPR just for safety on the fueling so no idea if it underfuelled - $300 all up.. bargain for some reliability.

[WazR32GTSt]

well i have the turbo, i may as well get it installed.

if the lag sucks, i'll just bite the bullet and get some cam gears...

now, if i can jsut find some barstard that will actually sell me their elbow pipe, then i'm in business

if i had a dollar for everyone that "didnt want to separate" or "sold it already" then i would have a GTR by now...

[WazR32GTSt]

time for an update...

in perth i visited a parts shop and picked up an elbow pipe for $15 !!

so now i'm set for the turbo

and.. visited our friends at Mercury Motorsport, ordered cam gears and booked in rb25 turbo install, cam gear install, and cam gear tune on the dyno

they guy suggested fuel pump and told me about a $350 walbro option.. i suggested a gtr pump that i know i can get for $100ish, but he said they are old and not worth it.

did the gtr pump work ok for you, gordo?

anyone else had any experience with fuel pumps after an rb25 install?

[predator]

did the gtr pump work ok for you, gordo?

anyone else had any experience with fuel pumps after an rb25 install?

They may be old, but at least it works unlike the walbro.. I'm just down on the whole walbro pumps after a brand new one died in less than 3 months (thankfully not under high load conditions). I've never heard of anybody that has had a Bosch unit die on them.

[TTT]

$350 for walbro?

they are like $200 from an EXPENSIVE source.

I had a R32 GTR fuel pump in my silver r32 and it worked fine for over a year that I owned it... it came out of a 110,000km 92 GTR.

Walbro I bought I installed in my S14 and then the car was pinched after about 3 months so I can't really say any good or bad points about that one.

if you can get a gtr one for $100, then go ahead.

I might have to go visit this mercury place when I move up there.

let me know what they charge you for the turbo install.

[WazR32GTSt]

GTST - i'll PM you once its all installed with the cost (as i don't think its right to quote figures over the internet)

tey are a sponsor of hte SAU-qld club so do labour for cheaper if you are a SAU-qld member

also, they have a 4wd dyno and a dedicated s15 that they race, so they are quite the professional outfit

let me know when you come up and i'll take you out there if you like..

as for the fuel pump issue...

i was told that the reason they preferred walbro over bosch is that they are easier to install..

he actually said that the gtst pump would probably hold up ok, but the fact that its 14 years old is not worth the risk.. and the gtr pump would pose the same issues as its euqally as old

car is booked in for monday.. can't wait to see the difference it makes. last power figure was 132rwkw (with 10.5:1 AFRs), so add in rb25 turbo and cam gears and hopefully something over 140rwkw should be attainable

[ellie]

Hey mate, I installed a bosch pump into my R32 GTS-T and never looked back! The problem with the fuel pumps in the gts-t's is they don't actually just stop so you need a new one, oh no, they like to play games - cutting out intermitantly, running at a slower speed and occasionally they'll only be capable of one of the 2 stages expected of it! So if you're wanting to start getting more performance then don't skimp on this item and go the bosch straight up.

Cost me $280 self installed and there's a DIY in the tutorials section

From memory, the standard pump was rated at 165L/h and the pump I selected was rated at 185ishL/h

My model had an internal built in check valve which is also important

The 040's and 044's that are whored everywhere are rated at 240L/h or so. Huge over kill unless you have a powerful GTR. No check valve so you have to set it up externally and are an open base feed type which shouldn't be used in a skyline tank!

Also don't look at that "capable of 600HP" crap either that walbro love to bandy round. The pumps job is to supply an adequate amount of fuel to the motor. So L/h is where it's at!

Work shops will always want to sell you the easy option because it makes them the most amount of money for piss all time. Research, get what you're happy with and tell them what you want them to do.

Hope that helps somewhat

Waits for rebutle

[WazR32GTSt]

yeah when he said abotuhe fuel pump i knew it should be considered, but was hesitant when the 300 came out

it does make sense - most profit for the least work.. after all they are a business

i might just do it without the fuel pump, and do some research in the next few days about what to get fitted, and then i can buy one myself (save them marking the price up too) and then get it fitted in the next few weeks.. i am going back for some king springs soon so can get that done with it

[Roy]

You still got those cams in the engine?

[ellie]

Don't quote me on it as it was a while ago now but a bosch pump with the same flow of 165L/h was a

XXX XXXXXXXXXX915 and the one i got was a

XXX XXXXXXXXXX985 If you can get hold of a bosch catalogue tomorrow, it's all in there

[WazR32GTSt]

ellie - cheers

roy - of course i do. that's part of the reason why i wanted to go cam gears as i thought they might bring that bit extra out of the rb26 cams. but i always worry that whenever someone play around with things in that region it will fail to idle like others have found.. fingers crossed they know what they are doing!

will put up dyno graph when its done

what does everyone think about a power rise from the rb25 turbs and can gears? i'm hoping for 15rwkw top-end plus some mid...

(PS to those who usually jump in here.. please let's not get this whole rb26 cam thing started again!)

[Roy]

roy - of course i do. that's part of the reason why i wanted to go cam gears as i thought they might bring that bit extra out of the rb26 cams. but i always worry that whenever someone play around with things in that region it will fail to idle like others have found.. fingers crossed they know what they are doing!

I regret the day i played with the cams...being such a hack i farked up my then perfectly good/neat car...since then it has bene nothing but blown engines, hitting walls and catching on fire....but this time round i know better. Dont forget the rest of the RB26 when i throw the cams in

[WazR32GTSt]

final update...

picked up the finished car today:

- rb25 turbo

- HKS cam gears

- fuel pump

- dyno tune

old setup (minus the above) with 13psi and timing set to about 25deg BTDC made 132rwkw

new setup with cam gears at 0 and 0, with 11psi, and timing at 15deg BTDC made 133rwkw

new setup with cam gears tuned (intake +3, exhaust -5), with 13psi, and timing at 17deg BTDC made 154.8rwkw!

the most power came in the midrange too!

will post a graph as soon as i scan it

[Tangles]

you will need that elbow... I don't know why people take them off, but they seem to 'disappear' regularly.

Sorry mate - I never got the elbow as part of the deal when I bought that particular turbo (and never used) which you then bought off me (at my $200-odd loss!!! LOL).

Chase up a fella called Hooman (sau member) who sold me that turbo - he might have an elbow piece lying around, but then again he's a hardcore lier, so if you do find him, just smash his kneecaps for me pls. LOL again.

All the best with it - $100 install is a bargain; take it up and shout him some bourb's as well!

edit - read the rest of the thread... NICE WORK!@!!!

IM GLAD IT TURNED OUT FOR YOU, MATEY! lol

Edited April 27, 2006 by Tangles

[TTT]

nice work warren.

as SK has said many time before..

the rb25 turbo flows 15% more at the same boost as the rb20 turbo.

yes you made a few other mods but 13psi on rb25 turbo making about 155rwkw.

take away 15% (which is about 23) and you have 132rwkw which was your old set up.

nice.

I'll have a talk with you about these cams when I finally get up there and settled in.

[lows_13]

Realisticly the RB25 turbo is only a mild upgrade on a RB20DET, what would be next in line after that?

[TTT]

hi flow rb25 turbo

hks 2530

anyway, just found a dyno sheet from my old r32

had turbo back 3 inch

Blitz panel filter

turbo xs bleed valve

rb25 turbo

arc side mount intercooler

it was manual too.

11psi gave me 153rwkw on some dyno on shoot out mode.

stock computer had A:F at 12:1

room temps were 35 degrees

[lows_13]

What peoples opinions on these larger side mount cooler upgrades? (ARC, Trust, etc)

Are they worth the money?

What sort of power will they support?

[StealthX]

new setup with cam gears tuned (intake +3, exhaust -5), with 13psi, and timing at 17deg BTDC made 154.8rwkw!

good form!

midrange tourque FTW!