How can Rb25det rev be fixed

[smiley]

I am going to buy a rb25det and a friend is telling me to get the rb20det becuase it was a better rev happy engine and im thinking wtf...

why does the rb20 outrev teh rb25..... i hope this doesnt mean when im done with my project in low gears a rb20 will catch me

[Joe]

RPM does not equal horsepower. just because it can rev to X thousand rpm dosent mean its makes power. i GUARNTEE the RB20 turbo doesnt make power anywhere past 6500rpm, so theres no point.

you guys used to own hondas didnt you?

[smiley]

nope.... only a camaro lol was just askin , hey im curious... what mods do yuo require to spit flames lol...

saw a pic of a friends rb spittin fire

[Yellow4g63]

RPM does not equal horsepower. just because it can rev to X thousand rpm dosent mean its makes power. i GUARNTEE the RB20 turbo doesnt make power anywhere past 6500rpm, so theres no point.

you guys used to own hondas didnt you?

Ha! got you http://nissaninfiniticlub.net/...o.jpg

My peak power is after 6500. To get any motor to rev better a lighter flywheel will help. Cams move the power band higher. Unless your making a race only motor don't worry about revs. If you really want revs buy a SR20DET and do a SR20VE/SR16VE head swap. Peak power on a N/A SR20VE is 7200 and SR16VE cams push that to 7500.

[Joe]

Ha! got you http://nissaninfiniticlub.net/...o.jpg

haha

look at the curve. see how it peaks at around 6500?

thanks for proving my point.

also, what mods were those?

nope.... only a camaro lol was just askin , hey im curious... what mods do yuo require to spit flames lol...

saw a pic of a friends rb spittin fire

[eh?]

displacement > revs. Also there is no reason the RB25 can't rev as high as the RB20.

[Shocker]

better flowing turbo, cams, and a power FC, you can rock it out to 7500-8000, bobnissan was reving his to almost 9 k with stock head, i dont really recommend that, but his held up lol.

[eh?]

better flowing turbo, cams, and a power FC, you can rock it out to 7500-8000, bobnissan was reving his to almost 9 k with stock head, i dont really recommend that, but his held up lol.

Head isn't the problem, it's the oil pump... his took a dump but I'm not sure if it killed the motor.

[gawdzilla]

i've seen an ae86 rev to 13k before.. SICK!!

... on intial d

[Joe]

Head isn't the problem, it's the oil pump... his took a dump but I'm not sure if it killed the motor.

its more than a pump problem

its a design problem. it actually flows too much oil into the head wich in return leaves not enough in the pan and, violla. spun bearings

the pumps are an issue, but its a combo.

[Shocker]

yeah, besides his motor was still intact, his PT took a dump when the set screw on the compressor wheel backed itself out and began flowing oil straight out of itself. into the exhaust.

[mugengsr]

displacement > revs. Also there is no reason the RB25 can't rev as high as the RB20.

displacment>revs ??? explain an F1 engine or a super bike ?? lol j/k

as for rb25 not reving like the rb20 ... well its true the rb20 can rev higher and be stable as it has a better bore stroke ratio

[Yellow4g63]

haha

look at the curve. see how it peaks at around 6500?

thanks for proving my point.

also, what mods were those?

It dosen't peak at 6500, it's after 6500 more like 6600-6700. That was after I added the Intakemanifold and FMIC.

[Shocker]

It dosen't peak at 6500, it's after 6500 more like 6600-6700. That was after I added the Intakemanifold and FMIC.

lol that extra 1-200 rpms... big deal there.. still point being said it isnt making any further power, a 25 chart will look almost the same with similair mods, just higher hp :P...

ive been reading on how to make a 25 saftly rev lately, seems to be an oil problem as kamin said, it is the same with ALL RB motors, over oiling the head at extended high rpm uses.. such as track.. drifting.. drag... or just a crazy weekend mashing.

but its fixable, by blocking one of the heads oil feed, and putting a restrictor in the other, allowing less oil to enter the head at once, allowing for it to drain safely back to the pan in time for it to be picked back up.

some ppl in au do a "bandage" method, slightly over filling their pan to the hump on the dipstick, gets an extra liter or so of oil in there, w/o over flowing.. so theres more oil to begin with so it lesses the risk of running dry of oil in the bottom end.

[Kansei240sx]

RPM does not equal horsepower. just because it can rev to X thousand rpm dosent mean its makes power. i GUARNTEE the RB20 turbo doesnt make power anywhere past 6500rpm, so theres no point.

you guys used to own hondas didnt you?

LOL

ps. You wouldnt think that adding to much oil would as per say, windage like you'd get in a transmission from adding to much oil eh?

[Yellow4g63]

lol that extra 1-200 rpms... big deal there.. still point being said it isnt making any further power, a 25 chart will look almost the same with similair mods, just higher hp :P...

??? I'm just pointing out that it makes power past the 6500rpm point. My friends made 275hp with the same mods on his RB25. I wonder why he didn't blow me out of the water when we raced from a roll? I thought the RB25 could never lose lol.

[eh?]

its more than a pump problem

its a design problem. it actually flows too much oil into the head wich in return leaves not enough in the pan and, violla. spun bearings

the pumps are an issue, but its a combo.

From what I've seen you'll realize that issue after the oil pump problem is solved. I've seen a few oil pump gears cracked before the person realized they had a problem. Where each problem starts I don't know- all I know is keep your rev's below 8k.

[eh?]

??? I'm just pointing out that it makes power past the 6500rpm point. My friends made 275hp with the same mods on his RB25. I wonder why he didn't blow me out of the water when we raced from a roll? I thought the RB25 could never lose lol.

He was making more HP but didn't beat you badly enough. Why put the blame on the RB25?

[Joe]

It dosen't peak at 6500, it's after 6500 more like 6600-6700. That was after I added the Intakemanifold and FMIC.

seriously, 200rpm difference?

your manifold did that. and give me a break, 200rpm....and it LOOKS like a fake spike on the dyno anyway

your OVERALL CURVE ends at 6500rpm. making power past that will require money. lots.

[Yellow4g63]

seriously, 200rpm difference?

your manifold did that. and give me a break, 200rpm....and it LOOKS like a fake spike on the dyno anyway

your OVERALL CURVE ends at 6500rpm. making power past that will require money. lots.

Hmm you said

i GUARNTEE the RB20 turbo doesnt make power anywhere past 6500rpm, so theres no point.

I guess even with the evadence right in front of you ? You kill me hahaha.

[Yellow4g63]

He was making more HP but didn't beat you badly enough. Why put the blame on the RB25?

I never said he beat me lol. It was the other way around.

[eh?]

I never said he beat me lol. It was the other way around.

And that proves the point further. Does the RB20 have some magic fairy dust that makes a 240sx go faster when it doesn't produce more power?

[Shocker]

I never said he beat me lol. It was the other way around.

psh.. ive still yet to a see a BPU 20 break 12's... i havent been to the strip in a while, but i ran a [email protected] with a 1.85 60 at stock boost on an 80 degree day. toad, got his 25 to a 12.5 at 10 psi.... once again lets see a BPU 20 do that..

sorry to thread jack... was bothering me.

[Yellow4g63]

Eh? I guess my motor has some magic fairy dust in it.

Shocker I don't like to bench race. I never made it to the 1/4 after I got my fmic and intake manifold. I got 2 chances when I just had intake and exhaust and only got a 13.7@99 mph with a crappy 1.9 60'. Ohh and BPU? I use to see supra guys say that alot. Dose BPU mean intake and exhaust?