dyno'd my rb20 fri night

[b00stinbmx]

so my girlfriend is friends with a guy down at pruven performance in milford,CT so i went down there with her fri night to check out his car and the shop. i had the 240 with me so he offered to put it on the dyno. i was always wanting to since i completed the swap but never bothered. anyway...

car made 219whp and 184 lb/tq. which i don;t think is too bad for a stock rb20. problem is my AFR's were ridiculously high. running around 14.3 on full boost. i had a aem wideband just hooked up so i kinda knew of this. the guy bill who is a tuner and has a lot of knowledge told me that its prob ok but im loosing a lot of power due to the ecu pulling timing a lot to compensate for the engine knock im probably getting. i figured this was due to me using a maxima n60 MAF since i never got the proper RB one with my swap. im hoping i can squeeze maybe 20hp or more out if i get a tune to compensate for the different MAF. but he also suggested just getting a adj. FPR and see if that will help. im running a 255lph walbro but i guess its really just my MAF thats cockblocking my AFRs. just figured id share some of this info and see what you guys thought. being mostly DSM guys they all seemed to like the car a lot though and thought it was pretty cool. but unfortunately i got nothin on his 700hp+ talon

[krayton]

huh?

so does this n60maf even work without a tune or anything on rb20s?

is it scary u drive around with 14afrs on full boost knowingly. or is it worse u went to get it dynoed and the tuner with his 700hp talon doesnt say anything about driving around with those afrs

[b00stinbmx]

well if the car is pulling timing like he said then why would it be terrible. all he told me is that im losing power because of it and i should def get it fixed soon. so yea i guess that answeres the qusetion about if n60 mafs can be used without a tune and i guess they can but they are leaning the motor out

[b00stinbmx]

[Carl H]

your 'tuner' is a moron.14:1 is NEVER safe on a boosted car, cruise and idle thats it.does the aem incar correlate to the tail pipe wideband...ether way you need to figure out whats up; either device readings are wrong or you really are running 14:1.in theroy power sounds about right for a stock rb20, afrs dont but it hasnt blown up yet so chances are their wideband sensor is toast.stock ecu can pull some timing but not alot, it does not have the 5* active advance/retard that a dsm has...set map timing is set map timing cant go below that.

[dtowngoalie]

Yea 14.0 is so lean haha, almost can't be right

[maryjane]

timing has to be off to be running a 14 flat afr. why are you not running a stock 20 maf? you think your making a gain by switching mafs or did your swap not come w a maf?

hint dont boost till you fix that or your gonna break a ring land or crack a ring

[20DET]

bro incase u didnt realise 14.1 is RICH not LEAN...anything under 14.7 is RICH and anything over 14.7 is LEAN...

its running rich from the walbro pump and the reg not getting it back to tank fast enough

READ

http://en.wikipedia.org/wiki/Air-fuel_ratio

[b00stinbmx]

yea i was kinda thinking that their tailpipe sniffer might be off a little. my wideband is showing more like a 13ish at full boost but im not going to drive it anymore till i get it fixed. i have a real main seal leak now anyway so that needs to be fixed as well. and no i didn;t switch MAFS cause i thought i was going to gain anything. i am using it because i didn;t get one with my swap and i was told that the n60 would work fine.

and yea i don;t really think hes a "moron" but like you said if dsms have the ability to correct timing that much thats probably why he told me that not knowing that the RB would do the same. anyway like you guys said im not going to drive it anymore cause the car is running good and i don't want to F anything up. going to get this straightened out before i do anything else.

[Carl H]

uh oh do we have another non believe in what is ideal and what is reality...i think we do!

bro incase u didnt realise 14.1 is RICH not LEAN...anything under 14.7 is RICH and anything over 14.7 is LEAN...

this is hardly the case, 'bro', an fi car should NEVER be run leaner than 12.5:1 and that is the ragged edge where a bad tank of gas can do the motor in...in an NA car leanest I'd ever go is 13:1 but even then I run them rich just in case.14.7:1 is stociometric which means that for every 14.7 parts air 1 part fuel is consumed, it is a chemical equation which is ballanced...however it is far from ideal in an engine aside from idle and light load (cruise).

its running rich from the walbro pump and the reg not getting it back to tank fast enoughREADhttp://en.wikipedia.org/wiki/Air-fuel_ratio

you're correct in saying a rich condition can be created by a walbro pump which 90% of the ones on the market will run 10psi high nominally, never understood why the high pressure pump was sold vs the standard pressure...would aleviate the need for an adjustable fuel pressure regulator on a stock engine.

I strongly reccomend you do some reading on engine fuel tuning before you tell some one that its ok to be boosting at 14:1.

[Yellow4g63]

bro incase u didnt realise 14.1 is RICH not LEAN...anything under 14.7 is RICH and anything over 14.7 is LEAN...

its running rich from the walbro pump and the reg not getting it back to tank fast enough

READ

http://en.wikipedia.org/wiki/Air-fuel_ratio

lol I think I have heard that before.

[PorkChopExpress]

the 255 and 255hp flow the same until you get over 70psi. only difference is the relief valve. why would people run it that high? well i run my base fuel pressure at 55 psi to get the most of my 440s.

[maryjane]

bro incase u didnt realise 14.1 is RICH not LEAN...anything under 14.7 is RICH and anything over 14.7 is LEAN...

its running rich from the walbro pump and the reg not getting it back to tank fast enough

READ

http://en.wikipedia.org/wiki/Air-fuel_ratio

OMFG another one of these!!!

haha! your the second retard that has said that! haha! sure run your motor at wot (under boost) and tune it for a 14.7 afr, hope youve got deep pockets!

this is for you

thanks for a new sig!

[mattblancarte]

14:1 is ridiculously lean for a boosted car.

If I were tuning for pump gas, I wouldn't go any leaner than 11.8:1. My car is tuned at about 12.3:1 and I run 101 octane.

[Yellow4g63]

OMFG another one of these!!!

haha! your the second retard that has said that! haha! sure run your motor at wot (under boost) and tune it for a 14.7 afr, hope youve got deep pockets!

this is for you

thanks for a new sig!

LoL nice now you have one for your sig too.

[EVILS14]

i was just wondering why your girlfriends is friends with a guy you dont know

[maryjane]

shes looking for that outside di^k

[Carl H]

keep it clean else this thread gets locked.

[Sil240]

I've heard of Pruven they're supposed to be good. Evo's etc...

Maybe you've got an exhaust leak, and some air is getting in. Could be why your getting a lean signal....

Try your wideband on a friends car and try his on yours.

They should have similar readings to each other, if not the same.

[b00stinbmx]

well thanks for the help. im assuming its gonna be something stupid. i checked my aem and it never read 14 more like 12.7-13 ish on full boost which still seems high but there is a high chance of a small exhaust leak if that would matter. either way what i was really trying to get at was would the rb even make that power given it was running that lean? the other thing i might add is i've been driving the piss outta the car before this dyno pull. if it was that bad i would have figured something would have happened already. either way thanks for the help from some of you who had something smart and on topic to say.

on a sidenote i should have gotten technical and said it was my gfs cousins best friend, or better yet nothing at all, so that way people wouldn;t have to worry about that please don;t post garbage in my thread so it gets locked since im just trying to get some info here.

[rb25det250sx]

do you have a 20, or 25??

OP says 20, but in your users thing it say 25..??

[b00stinbmx]

20. forgot to change that user thing.

[mattblancarte]

I'm surprised the tuner didn't have a wide band to stick into your muffler...

[b00stinbmx]

uhhhhhhh.....

he did man, thats where the readings from the dyno chart came from....

[mattblancarte]

Oh my bad, I thought you were taking the dyno readings from a wide band bunged into your manifold or downpipe. edit: durr, I skipped over a few of the posts above, on accident.

Ya if you are reading in the high 12's on your AEM, and you're reading 14's out of the muffler, one would think you have a leak somewhere in between.


Modified by mattblancarte at 7:19 PM 8/10/2009

[bounty212]

u should be ok with that n60 maf im running the same thing on my rb20 right now since my motorset came without a maf.. nice to see another local rb....

[b00stinbmx]

its all good. yea thats what i figured. that or their wideband is just screwed. im pretty certian mine isn;t its a pretty much brand new aem uego used on my buddies wrx for a few months then my car. i dunno i guess im gonna keep drivin it. and bounty 212 you on 240sxone?

[Joe]

bro incase u didnt realise 14.1 is RICH not LEAN...anything under 14.7 is RICH and anything over 14.7 is LEAN...

its running rich from the walbro pump and the reg not getting it back to tank fast enough

READ

http://en.wikipedia.org/wiki/Air-fuel_ratio

HOLD THE f*** ON

you made a thread about how a stock regulator and walboro will NOT make the car run rich

zerothread?id=439302

now youre changing your story? i thought you were the all knowing mechanic?

im not even going to go into how wrong you are about AFR's.