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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

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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

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