Jump to content
SAU Community

Recommended Posts

ive got a worked rb20 with around 240 260 rwkw mark

my boost comes on full at 5000

ive been thinking about changing my diff gears reason being:

for the street - on take off at resonably low revs say 3000rpm ive got pretty much no power

what do you guys think?? id like to be able to launch at lowers revs and have a bit more power to accelerate quickly

i know i would probably wheel spin way easier than even now but would it be too much?

could i get a good set of treads and still do the gears

just want your veiws?

im kinda sick of V8's pulling away from me off the line thinking they just beat me in a drag when i dont launch at 6000

if you know what i mean

Link to comment
https://www.sau.com.au/forums/topic/261130-r32-thinking-about-new-diff-gears/
Share on other sites

well if boost is coming on at 5 grand theres a few obvious issues

1) how is the tune?

2) what size turbocharger housing? its obviously too big

3) displacement vs power output - ie your trrying to make too much from a small engine

diff gears will help but i would look at what size rear housing you have

if you can change both, that would make a massive difference

dont bother with antilag, its not a street friendly, use daily solution

ok i reckon my car would drill any other rb20 with a smaller turbo

the rb20 is made to rev and ive even put both dyno's up against eachother with my turbo it only comes on power 500rpm later than a 2530 (small turbo good response) with about 40 kw less

anyway i just took it for a drive and launched it at around 4 - 4500 rpm and its actually quicker than i thought

it came on boost straight away and took off sideways

maybe im trippin id just like that lttle bit more in low revs

are you talking about a shorter or longer diff ratio?

a shorter diff ratio will make it come on boost at a higher rpm in the same gear, but you'll be doing less speed when it comes on boost. a longer diff ratio will bring it on boost at lower rpm but higher speed

a ratio that'll give you more in low revs will make the car slower overall, in general

Put in the gears or whole diff from an R32 auto.. it has a 4.3 ratio.

will give you a lot quicker acceleration down low which is fun for a street car. You will top out at around 200km/hr with those ratios, but for a street car that's probably not a concern.

i left my auto diff in my 33 when i done a conversion. personal, i think it would be a waste as i have 300 hp but cant get it to the ground as it zips through the revs and easily lights up the back wheels in 1st. slight loss of traction in 2nd when boost cuts in. a taller gear ratio would help stop this. the only way to stop this is get on the go peddle a bit slower.

He already has a 4.363 diff ratio so.... didnt you change the turbo from teh 3082 or whatever it was you were running? But you now seem to have as much lag as you did before?????

You can change the diff (i havent changed mine...its an option as i am about to go to a larger frame of turbo) but really if you want response or you can do is go smaller frame turbo. You may get minor improvements if you put the std inlet manifold back on or get a better manifold...depending on what you are running at present.

But yes, a 4.6 diff will help it come on at lower road speeds, but keep in mind that since you run 16" wheels you will be reving at about 4,000rpm on the highway :banana:

Put in the gears or whole diff from an R32 auto.. it has a 4.3 ratio.

will give you a lot quicker acceleration down low which is fun for a street car. You will top out at around 200km/hr with those ratios, but for a street car that's probably not a concern.

Got one of these in mine. I top out at 250.

yeah went with the 3071r but found out that the spring in my wastegate was only a 12psi spring so it was opening up and not holding boost as well as it should so that is contributing to the lag

it will be much the same as the td-o6 brisby....

id like to compare mine and yours one day just to see if we can make any other improvements to the setups

i cant yet say what power cause im still wating for a 17psi spring and final tune but we did a small test to see by holding the gate closed and it made 4psi more at the same revs by closing it

i think it made like 184kw at just under 5000rpm with the gate closed

so we still have 2000rpm from there to play with at full boost

im sure i will see 260rwkw quite easy at 19psi

the old tune with the old turbo made 260 but we detuned it

this turbo does feel just that slightly more responsive but not much and i think im making around the 220 230mark

now at 17psi with the 12psi spring still

im still unsure bout cams cause for the money to install/tune ect ect ect wont be a major difference

as for engine work i flowed the head just a mild port and i chucked on a plenum

i think i just gotta get used to the real loud REVS of my car off the line and just get used to people looking at me thinking im another idiot hoon on the street

cause the only way to launch an rb20 is to give it all most of us guys would vouch for that.

even with a stock turbo it was laggy

i just reckon maybe diff gears would change it a little but your right then the revs would be higher at cruising speeds (100km)

and i reckon they are already high as is also with a good launch it just wheelspins it would be way worse with diff gears

but anyway i was just thinkin out loud

when is the next drift/track days ???

the last drift day was awesome

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • As discussed in the previous post, the bushes in the 110 needed replacing. I took this opportunity to replace the castor bushes, the front lower control arm, lower the car and get the alignment dialled in with new tyres. I took it down to Alignment Motorsports on the GC to get this work done and also get more out of the Shockworks as I felt like I wasn't getting the full use out of them.  To cut a very long story short, it ended up being the case the passenger side castor arm wouldn't accept the brand new bush as the sleeve had worn badly enough to the point you could push the new bush in by hand and completely through. Trying a pair of TRD bushes didn't fix the issue either (I had originally gone with Hardrace bushes). We needed to urgently source another castor arm, and thankfully this was sourced and the guys at the shop worked on my car until 7pm on a Saturday to get everything done. The car rides a lot nicer now with the suspension dialled in properly. Lowered the car a little as well to suit the lower profile front tyres, and just bring the car down generally. Eternally thankful for the guys down at the shop to get the car sorted, we both pulled big favours from our contacts to get it done on the Saturday.  Also plugged in the new Stedi foglights into the S15, and even from a quick test in the garage I'm keen to see how they look out on the road. I had some concerns about the length of the LED body and whether it'd fit in the foglight housing but it's fine.  I've got a small window coming up next month where I'll likely get a little paint work done on the 110 to remove the rear wing, add a boot wing and roof wing, get the side skirt fixed up and colour match the little panel on the tail lights so that I can install some badges that I've kept in storage. I'm also tempted to put in a new pair of headlights on the 110.  Until then, here's some more pictures from Easter this year. 
    • I would put a fuel pressure gauge between the filter and the fuel rail, see if it's maintaining good fuel pressure at idle going up to the point when it stalls. Do you see any strange behavior in commanded fuel leading up to the point when it stalls? You might have to start going through the service manual and doing a long list of sensor tests if it's not the fuel system for whatever reason.
    • Hi,  Just joined the forum so I could share my "fix" of this problem. Might be of use to someone. Had the same hunting at idle issue on my V36 with VQ35HR engine after swapping the engine because the original one got overheated.  While changing the engine I made the mistake of cleaning the throttle bodies and tried all the tricks i could find to do a throttle relearn with no luck. Gave in and took it to a shop and they couldn't sort it. Then took it to my local Nissan dealership and they couldn't get it to idle properly. They said I'd need to replace the throttle bodies and the ecu probably costing more than the car is worth. So I had the idea of replacing the carbon I cleaned out with a thin layer of super glue and it's back to normal idle now. Bit rough but saved the car from the wreckers 🤣
    • After my last update, I went ahead with cleaning and restoring the entire fuel system. This included removing the tank and cleaning it with the Beyond Balistics solution, power washing it multiple times, drying it thoroughly, rinsing with IPA, drying again with heat gun and compressed air. Also, cleaning out the lines, fuel rail, and replacing the fuel pump with an OEM-style one. During the cleaning process, I replaced several hoses - including the breather hose on the fuel tank, which turned out to be the cause of the earlier fuel leak. This is what the old fuel filter looked like: Fuel tank before cleaning: Dirty Fuel Tank.mp4   Fuel tank after cleaning (some staining remains): Clean Fuel Tank.mp4 Both the OEM 270cc and new DeatschWerks 550cc injectors were cleaned professionally by a shop. Before reassembling everything, I tested the fuel flow by running the pump output into a container at the fuel filter location - flow looked good. I then fitted the new fuel filter and reassembled the rest of the system. Fuel Flow Test.mp4 Test 1 - 550cc injectors Ran the new fuel pump with its supplied diagonal strainer (different from OEM’s flat strainer) and my 550cc injectors using the same resized-injector map I had successfully used before. At first, it idled roughly and stalled when I applied throttle. Checked the spark plugs and found that they were fouled with carbon (likely from the earlier overly rich running when the injectors were clogged). After cleaning the plugs, the car started fine. However, it would only idle for 30–60 seconds before stalling, and while driving it would feel like a “fuel cut” after a few seconds - though it wouldn’t fully stall. Test 2 – Strainer swap Suspecting the diagonal strainer might not be reaching the tank bottom, I swapped it for the original flat strainer and filled the tank with ~45L of fuel. The issue persisted exactly the same. Test 3 – OEM injectors To eliminate tuning variables, I reinstalled the OEM 270cc injectors and reverted to the original map. Cleaned the spark plugs again just in-case. The stalling and “fuel cut” still remained.   At this stage, I suspect an intermittent power or connection fault at the fuel pump hanger, caused during the cleaning process. This has led me to look into getting Frenchy’s fuel hanger and replacing the unit entirely. TL;DR: Cleaned and restored the fuel system (tank, lines, rail, pump). Tested 550cc injectors with the same resized-injector map as before, but the car stalls at idle and experiences what feels like “fuel cut” after a few seconds of driving. Swapped back to OEM injectors with original map to rule out tuning, but the issue persists. Now suspecting an intermittent power or connection fault at the fuel pump hanger, possibly cause by the cleaning process.  
×
×
  • Create New...