Wack Dyno numbers???

[ONE80ESSEX]

I have a huge problem that needs to be solved!

This is what I have on an internally stock redtop SR20

-RB25 T28
-stock SR ex manifold
-Custom d/p with "screamer"
-650cc
-Z32 MAFS
-walbro 255
-front mount
-3 inch d/p back exhaust
-type S BOV
-Manual B/C set at 12 lbs

Heres what I made

183 hp
181 tq

The way I tuned was, I had a guy make a chip that was made for the set up i have (ROM TUNE) and he was basically going to use the wideband on the dyno to fine tune it. The A/F ratio is between 11.8-12.6 across the board. I dont have a boost leak, my compression is good and the timing is good.

NOW WHAT THE FUCK IS UP!!!

Please and help or suggestions would help a lot!

[EDacIouSX]

that might actually be right.... cause stock sr gets like 160 @ wheel so... if that is [email protected] wheel then it looks a little bit low but not too low. What are you boosting at?

[kamikazekid]

sounds like your not boosting correctly. might be that manual B/C.

[used240sxparts]

lol phil i love you...


-eddie

[used240sxparts]

its on 12lbs

[ONE80ESSEX]

that might actually be right.... cause stock sr gets like 160 @ wheel so... if that is [email protected] wheel then it looks a little bit low but not too low. What are you boosting at?


What! Theres no way! Before i did the upgrade, I had to of been making atleast 150 to the wheels on stock boost. So your saying after I put a bigger turbo, doubled the injector size and doubled the boost with a Z32 MAFS that ill only make 30 more hp..no way! Everyone else i know with a stock motor on 12 lbs makes well into the 200's with just upping the boost. And someone with 180 tq should be making mid 200's with stock internals.

[ONE80ESSEX]

sounds like your not boosting correctly. might be that manual B/C.

that could be the culprit, but i was holding 12 and then after like 5500 I would drop to 10 so its not like I was spiking 12 and going back down to like 3 lbs so idk.

[burnsauto]

that could be the culprit, but i was holding 12 and then after like 5500 I would drop to 10 so its not like I was spiking 12 and going back down to like 3 lbs so idk.

yeah i'd get a more reliable boost controller. also...whats your compression at? what kind of dyno is it?

[skylindrftr]

what rpm was max hp and tq?

[IN33DH3LP]

Your numbers seem kinda low to me. Especially with the T28, but I'm not an expert at Dyno Tuning. I have a CA18DET with the following:
XS Power FMIC
2.5" innercooler piping
2.5" intake piping, cold air intake
stock T25 turbo
3" downpipe and exhaust
Manual boost Controller (Hallman Boost Controllers)
Type RS BOV
444cc injectors
255 LPH Walbro fuel pump
stock internals
At 12 PSI I had 174 HP and 178 TQ to the wheels at 5350 RPM.
considering you have a larger turbo and a 2.0, I think your numbers should have been better. Granted your numbers are higher then mine, but it just seems like they should be higher and not within 9HP and 3TQ. Not trying to argue, I'm agreeing with you. Something seems weird about your numbers. Sorry, I'm usless and have no advice to give, just giving you something to compare it to.

[smelly240]

eek - i've seen stock boost t25's do better than that :(

have you checked your spark plugs, and do you have a graph for us?

Also - 11.8-12.6 isnt really a "safe" range for a street car (one that i imagine you'll be beating on regularly)... I wouldnt be happy with any afr's over 12.0 for a stock sr, but thats just me. Whats the condition of ur clutch? Did the fella tuning it datalog anthing for you?

usually t25's make that sort of power with just a fmic and exh... are u sure the turbo u got is a 28?

[fliprayzin240sx]

Healthy setup should see close to 160-180 on a stock T25 on stock boost. With a T28, closer to 200whp. At 12 psi, with a T28, you should see close to close to 250hp, Ive seen people put down closer to 270 on non-ball bearing T28s. AFs kinda high, shoot for 11.5 under load. Question is, who did the rom tune? Hows the timing on the car?

[Z U L8R]

....i made 240hp 260tq (i had a billet steel flywheel) on a bone stock sr20det with a front mount and exhaust at 14psi on the stock sr t25. my sr20 went 2 years at 14psi...granted i replaced 2 t25's then eventually went to an s14 t28, never had a problem with the s14 t28, and i ended up selling the car. the guy went a couple months then had valve train problems....as expected. rb25 turbo < s14 sr20 turbo. cermaic sux

you've got all the other mods except a good turbo. that's what the "culprit" is....you definately don't need 650's, if you were to get 550's then you'd be able to get an safc2 and not have to mess with the ecu, but whatever works for you.

if you put an s15 t28 on there and got some rocker arm stoppers you should be right at 290-310rwhp @ 17psi depending on tune, in GA we have 93 octane, i dunno about the gas where you're at but u shouldn't have a problem running 17 psi on 93 octane.

here's where my favorite debate comes in.

if you want more than 300-350hp you should have gotten an rb20. stock vs stock the sr20>rb20 BUT! doing the same upgrades, injectors, maf, turbo, tune. you'd be able to make rb20 350rwhp way more reliably than an sr20 at the same or even a little less hp. plus it sounds better, and revs higher. cam on valve ftw. sr20's have too common of valvetrain issues. the rb20 won't have piston problems @ 350hp if your tuner isn't a nub. just my 2cents.

upgrade your turbo. gt28/71'll put you at 330-360rwhp but you're gonna be pushing the motor, and if you go passed 17-18psi i'd highly recommend 100 octane or better. gl man
Dave

[Koopa Troopa]

if you want more than 300-350hp you should have gotten an rb20. stock vs stock the sr20>rb20 BUT! doing the same upgrades, injectors, maf, turbo, tune. you'd be able to make rb20 350rwhp way more reliably than an sr20 at the same or even a little less hp. plus it sounds better, and revs higher. cam on valve ftw. sr20's have too common of valvetrain issues. the rb20 won't have piston problems @ 350hp if your tuner isn't a nub. just my 2cents.



Yeah, you wish.

There's all too many 450 whp+ stock bottom end SR's running around here for you to be saying the SR is going to have piston problems at 350hp.

[Enjuku Racing]

^hahahaha. RB20 is almost useless. Back on topic. the RB turbo you are using are you sure its an RB turbo, I would honestly get rid of it. You would be better off with the S14/S15 turbo. Ceramic exhaust blades suck.

[Z U L8R]

hahahhaa. ^ that's what i said

i had my sr20's back in 2000-2002. i never had any valve train issues with mine. but all i see nowadays are sr20's with valve train problems. dropping valves, the little shims inbetween the rocker and the top of the valves coming out etc etc etc. it's reformed my opinions of sr20's. i personally don't think they're all that great anymore. for a 4 cylinder, 4g63> sr20 all day long. some people need to expand their automotive knowledge across a broader horizon than solely nissan. a lot of internet racers are suffering from tunnel vision. i love nissan, i'm hardcore nissan all day long, but i'd buy a 2j over an rb26 all day long.

my emphasis is mainly people give sr20's too much credit and rb20's not enough. in all honesty i think rb20's are more reliable than sr20's. everyone was so quick to jump on the sr20 bandwagon, but if you talk to some of us rb guy's that don't stay stock forever and a day, you'll see for yourself, hp vs hp, mod vs mod, rb's a more reliable engine.

the guy with the same gt30/71r with a FULLY BUILT sr20 made 435rwhp and i believe the dyno was 315 peak torque which was at 5800 rpm.

my rb25 has ALL STOCK INTERNALS. all i have is a metal hg and arp studs. i make 350ft lbs @ 3700rpm, with a peak torque of 381ft lb's at 5500 with the same turbo as the sr20 guy.

he redline's at 7200, i can go to 7400 np.

here u may agree with me and say well rb25 > sr20. i just wish there were more guy's that would spend the time to build an rb20. shit the motor sets are only 900 bucks wtf!

sr20 upgrade the turbo, maf, injectors, +tune
rb20 upgrade the turbo, maf, injectors, +tune

let's say both motors get z32 mafs, 550's and a gt28/71r, everything else is stock, no cams or bottom ends, if you have info on the sr20 with or without RAS then fine but really. the example is who made 350rwhp the longest and didn't have a problem. or a least when the motor failed, what is the fix.

[steve shadows]

hahaha

I love threads like this.

"CUS EVERYONE IS SUPER GOOD TUNARSZ"

good luck man

maybe it's the dyno


whos this "guy" who made the chip for you car?

even if the AFR is on tap right, your timing map might be a stock one, because the "guy" doesnt know shit about

building timing maps for cars, so he left it as close to stock as possible.

go buy a standalone or a fake standalone like a power fc and get it tuned.

its worth every penny.

[ONE80ESSEX]

eek - i've seen stock boost t25's do better than that :(

have you checked your spark plugs, and do you have a graph for us?

Also - 11.8-12.6 isnt really a "safe" range for a street car (one that i imagine you'll be beating on regularly)... I wouldnt be happy with any afr's over 12.0 for a stock sr, but thats just me. Whats the condition of ur clutch? Did the fella tuning it datalog anthing for you?

usually t25's make that sort of power with just a fmic and exh... are u sure the turbo u got is a 28?

yea dude tell me about it, I do need to change my spark plugs but that shouldnt effect that much horsepower, im talking about im robbed like 50 hp.
And im sure the turbo is a T28 from an RB25, the guy that i bought it off of I work with and he had it on his motor before upgrading to a 60-1.


....i made 240hp 260tq (i had a billet steel flywheel) on a bone stock sr20det with a front mount and exhaust at 14psi on the stock sr t25. my sr20 went 2 years at 14psi...granted i replaced 2 t25's then eventually went to an s14 t28, never had a problem with the s14 t28, and i ended up selling the car. the guy went a couple months then had valve train problems....as expected. rb25 turbo < s14 sr20 turbo. cermaic sux

you've got all the other mods except a good turbo. that's what the "culprit" is....you definately don't need 650's, if you were to get 550's then you'd be able to get an safc2 and not have to mess with the ecu, but whatever works for you.

if you put an s15 t28 on there and got some rocker arm stoppers you should be right at 290-310rwhp @ 17psi depending on tune, in GA we have 93 octane, i dunno about the gas where you're at but u shouldn't have a problem running 17 psi on 93 octane.

here's where my favorite debate comes in.

if you want more than 300-350hp you should have gotten an rb20. stock vs stock the sr20>rb20 BUT! doing the same upgrades, injectors, maf, turbo, tune. you'd be able to make rb20 350rwhp way more reliably than an sr20 at the same or even a little less hp. plus it sounds better, and revs higher. cam on valve ftw. sr20's have too common of valvetrain issues. the rb20 won't have piston problems @ 350hp if your tuner isn't a nub. just my 2cents.

upgrade your turbo. gt28/71'll put you at 330-360rwhp but you're gonna be pushing the motor, and if you go passed 17-18psi i'd highly recommend 100 octane or better. gl man
Dave


yea man, thanks for the input. The only reason I went with an RB25 T28 is because it was on hand and I got it for 150 because my friend was selling it and it has very little shaft play and he did all the fab for it to work so i was like why not, i spent a little over 600 bucks on the set up so thats why I went with that turbo and I got the 650's because they were at hand also from a friend for 100 bucks. So i guess this is the result of going the cheap way out, but i didnt expect it to be like this.



^hahahaha. RB20 is almost useless. Back on topic. the RB turbo you are using are you sure its an RB turbo, I would honestly get rid of it. You would be better off with the S14/S15 turbo. Ceramic exhaust blades suck.

Lol agreed about the RB20, but yes I am sure its an RB25 turbo, it was off a Neo series 2 RB25. I was actually in the market for an S14/S15 turbo but could not find one in my price range at the time. And i wasnt planning on running more than 12 lbs so the rbt28 sounded good.


hahaha

I love threads like this.

"CUS EVERYONE IS SUPER GOOD TUNARSZ"

good luck man

maybe it's the dyno


whos this "guy" who made the chip for you car?

even if the AFR is on tap right, your timing map might be a stock one, because the "guy" doesnt know shit about

building timing maps for cars, so he left it as close to stock as possible.

go buy a standalone or a fake standalone like a power fc and get it tuned.

its worth every penny.

Thats funny you mention the dyno because at work I was talking to some guys about this dyno and they said its notorious for being off. One guy said he went there after going to a different dyno and put out 287 and went to the one I went to and made 229, and then went to a different dyno and put down 285 with the same set up all the time. So maybe it is the dyno but I want to wait to go to another dyno until I say thats the reason.

The guy that did the tune for me is locally known for his "good" tunes, ive never heard anything bad about him so i trusted his tune, and he did mess with the timing, we tuned the timing then adjusted it again and lost some power and went back to the timing he had before and gained power so im good on timing, its not like he left it alone.

But yea im thinking about, after this weekends drift event, trashing the whole setup and getting a S14 or S15 turbo with some 440's and an AFC or an ECU from EFI and enthalpy and call it a day making high 2's but i want to go to another dyno to see whats up for sure before doing that.

[swayray]

that also depends on the dyno...

mine was 205hp on the dyno pack...

but on the dyno jet i'm only pushing 180rwhp

sr20 redtop stock internals
stock manifold
megan elbow
hks downpipe
3" straight pipe w/ 5zigen resonator (no muffler)
blitz fmic bov
hks intake
walbro fp
veilside ECU w/top speed limiter removed, rpm limiter raised, fuel map/timing curve optimized for premium fuel

[steve shadows]

dynodynamics reads 15% lower than a dynojet...

usually dynapack is even with dynojet.

but dynojet is notorious for big numbers.

well good luck have your tuner go with you to the dyno next time.

[ONE80ESSEX]

dynodynamics reads 15% lower than a dynojet...

usually dynapack is even with dynojet.

but dynojet is notorious for big numbers.

well good luck have your tuner go with you to the dyno next time.

O great b/c the dyno was a dynojet and the tuner guy did go with me, he was there the whole time tuning it with his program from the wideband on the dyno. ughhhhh! this is so frustrating

[fliprayzin240sx]

Umm, if you think the spark plugs are bad or worst yet, the wrong spark plugs, why wouldnt you think thats the reason for your problems? Change the gawdamn things....Look up NGK BCPR7ES, theyre only $1.20 a fucking pop and gap them to .030.

As far as the RB20 ish, why do you think theres no demand for them? Cuz they fucking suck. Explain to me why almost every non-GTR R32 i've seen out here ditch them for SRs? True, you can build them, I personally know a guy who got a mixed/matched RB25 internaled RB20 engine that bumped the displacement to 2.4 But if you leave the RB20 just the way it is with bolt ons, they fucking blows. RB25 on the other hand, is pretty stout compared to the RB20s.

[steve shadows]

and rb26 is the only direct competition for the sr in the s-chasis

although i still dont like the understeering characteristics in certain entry's

during GRIP driving

its all in peoples BAD oppinions and right to having them though haha

[ONE80ESSEX]

that also depends on the dyno...

mine was 205hp on the dyno pack...

but on the dyno jet i'm only pushing 180rwhp

sr20 redtop stock internals
stock manifold
megan elbow
hks downpipe
3" straight pipe w/ 5zigen resonator (no muffler)
blitz fmic bov
hks intake
walbro fp
veilside ECU w/top speed limiter removed, rpm limiter raised, fuel map/timing curve optimized for premium fuel

this is exactly why I have a problem...

you got 180 hp out of that when i have a bigger turbo, bigger injectors, a Z32 mafs, and on 12lbs plus everything you got and we have the same hp! WTF!!

[swayray]

what was the ambient temperature during the dyno session... mine was 65 degrees F... also what do you have for cooling?

[Sir]

sounds like your not boosting correctly. might be that manual B/C.

that would be my guess too
I had 180whp on a shitty tune (to pass smog) a while back with my stock T25 running 8psi.

[ONE80ESSEX]

what was the ambient temperature during the dyno session... mine was 65 degrees F... also what do you have for cooling?

that was high, im in south florida so the temp was at 95 and I have a scrawny ass front mount and a koyo raditatior

[ONE80ESSEX]

that would be my guess too
I had 180whp on a shitty tune (to pass smog) a while back with my stock T25 running 8psi.

yea ill be getting an electronic one soon