2kMaxim

Did a couple dyno runs today. My mods are as follows:

-Short ram intake with stock resonator and K&N style filter
-Warpspeed test pipe
-Mandrel bent stainless mid pipes w/resonator delete
-Restored factory muffler
-+2 timing advance

I will post the graphs tomorrow.... But the numbers were as follows.....
178whp
195wtrq
I found this interesting....it seems those mods gave me almost no HP gains over a normal stock auto but quite a bit of torque over stock....this is based on what ive read because i dont have any "before" dynos. I also will say my A/F ratio went pig rich.....it was like 11/1.......im betting an safc tune would put me well over 200wtrq which is cool.

Thoughts?

ShocknAwe

iTrader: (3)

Well assuming residual loss over the years I suppose it does seem a bit low but every dyno is different. What dyno did you use? A dyno is best at gauging gains or losses not so much to say "my car has exactly xxx HP". A tune with the SAFC always helps with bolt-on mods and if you got some NWP spacers, you should be over 200hp. Someone is always selling an S/VAFC in the classifieds

2kMaxim

Now I'm just curious how bold I can get that torque..... Using the 20% tranny loss equation, stock I should have about 174wtrq....a 20 gain in torque is pretty awesome, since I bet 85% of the time torque is what affects my daily driving and not HP. I love the way my car sounds when its pulling from 2.5k-5k...I assume that's the torque area. Im also guessing that me keeping the pre cats in and then having free flow exhaust all the way out after that is what is preserving the torque, but also limiting the HP. If Vafc can dial me up to 205wtrq and another 10ish hp....ill have a similar wheel torque to a stock auto 5.5 gen. Ill accept that...thats pretty cool.

Rods03Max619

iTrader: (5)

So you are saying NWP Spacers will give him a additional 22hp to the wheels, I love the NWP Spacers but they are more for mid range power and a little up top, I wish they did though **** would be awesome....

To the OP get some Headers, and maybe a LW Pulley and WHAT TYPE OF DYNO.....

2kMaxim

Dynojet......which is kindof industry standard at this point.....so Im not about to go searching for some more "pessimistic" type of dyno to use. Yeah for the price of those spacers, I can't see myself doing it. Maybe if the car was brand new. What I do see myself doing though is buying a used Vafc and flattening out that godawful A/F ratio. Im not kidding it was laughable at WOT.....like 10.8-11 to 1 ratio..lol. Im just glad my car is running so damn strong at 172k miles and i can see that the mods ive done sofar were not for nothing. Hearing that De-k howl from outside the car instead of inside was a treat as well.

*as to headers i refuse to mess with all the o2 sensor nonsense with this car...i did it with my IS300 but sold that before i ever had the emmisions headache to deal with. Since its a cali car i was bale to bag the rear main cat without throwing any codes...so i consider myself lucky. Is that pulley really worthwhile?

Rods03Max619

iTrader: (5)

Your in Cali, if so what part, and on the Pulley for me yeah, and was pretty cheap like 65 bucks, some will say not worth it but me I think so, say 5-8hp, but nobody did a before and after but straight even if gave 4-5hp cool with me and yeah I know all about the industry standard of the Dynojets, hit a Dynojet 3 times, going on #4 soon since car is Tuned.....

2kMaxim

No, I have a cali exhaust layout with the o2 sensors...I dont live in Cali The Federal layout you cant ditch the rear cat without throwing a code....

Rods03Max619

iTrader: (5)

Get Headers and a o2Sim=NO CEL......

03GLEmaxima

You would see good gains midrange and top with the headers.. and that engine is bulletproof so I don't see why it wouldnt last you another 100k plus. Id run a compression/vaccume gauge test to see where your motors at and see if its worth it to continue modding. Oh and a mid-pipe to replace the helmholtz resononator would sound reallyyyy nice

2kMaxim

Clearly you didnt read where I wrote "resonator delete" I Have mandrel pipes already. No restriction from the test pipe back.......

I'm probably not gonna do a compression test...if my motor was lacking compression it wouldnt have pulled so strongly......Yeah headers, or at least y pipe would be fun, I agree but I really dont want to open that wormhole again....I know many people have o2 sims to keep a cel from coming on, but Ive yet to talk to many that actually go into the emissions testing place with them in and pass.

dwapenyi

iTrader: (3)

Before you go down the safc route, how old are your primary O2 sensors? Mainly the one in the front exhaust manifold? If it's old, replace it. O2s get tired and won't throw codes. A tired O2 tends to give bad gas mileage. Your a/f observation being rich is in line with those symptoms.

D Moolah

iTrader: (1)

He was implying you get a short ram intake to replace your Helmholtz air intake resonator. That would change the sound dramatically and might give you a couple extra ponies. Good numbers, pretty close to what I had in my 97 Maxima with the 00VI. I dropped around 176/195 with an VAFC dyno tune.

carsnwomen91

you should also add a y pipe, that gives a good lump of torque in the whole mid rpm range and it'll cost less then an safc and for sure over 200wtrq

2kMaxim

Oh ok......meh, I dunno....from what I read searching around this forum...the difference between an airbox delete/ cone filter setup and a regular ram intake is negligible. I've also heard the car actually runs better with a resonator to kill intake turbulence.

My o2's are new.......the only one i didnt personally replace yet is the rearmost one.

Yeah Im pretty happy with the numbers...they show I didnt mod it for nothing I honestly wasnt planning on getting a tuning computer until i saw that fuel curve....thats free HP! Well, not free...but you get it..lol.

Yeah ive heard this alot...I just reeeeally dont want to deal with o2 Simulators and all the emissions nonsense. Emissions places really dont care for that sort of stuff....lol

Max_Gator

You can look at your dyno graph and see where max torque is...

MoncefA33

iTrader: (6)

For a basically stock "AUTO" DEK that is actually good.

dwapenyi

iTrader: (3)

When I had my previous max I had a Y pipe and CAI and I remember 184 TQ. I think hp was 172...not sure foggy memroy on the hp number.

2kMaxim

Ahhh cool. So its likely I did pick up a few Hp over stock then? Just not as much as the torque.....must be my energy...lol......my Is300 was a torque queen too....i had 208wtrq before i sold it.

Ill try to post up the graphs when they email em to me...hopefully today

dwapenyi

iTrader: (3)

What kind of rims do you have? I had 17s when I did mine.

2kMaxim

16's like a boss :P

dwapenyi

iTrader: (3)

When I finally get round to doing my I30, it will be with its OEM 16s as well. Bigger rims look better but I want all my NA power

2kMaxim

Yeah for sure. Actually i like watching the 5 spokes spin better than the 6.....

dwapenyi

iTrader: (3)

I know you said you refuse to mess with a Y pipe because O2 emissions etc but, wow, its the biggest bang for buck mod on our cars. AND, added to all your mods, your car would really take off.

Holy cow.

2kMaxim

Im looking into it. I just discovered something that might be a game changer....i guess warpspeed makes a ypipe for the cali models that allows
you to retain the bank 2 precat. The guy told me on the phone it doesnt throw a CEL because we dont have a rearward o2 sensor. I need to research this more......

benjie

I had a warpspeed Y on my 99 Cali 5 speed and I've had no cel and I pass inspection everytime. I'm in NY.

carsnwomen91

i don't.get how it.would throw a code having a y pipe and removing cats... How can an o2 sensor know that?? I'm in Canada and emissions are becoming mad strict for the newer cars, cel equals a fail even for non emission related equipment (i know, stupid) but just make some extra o2 bungs and screw them in, no?

You should still pass emissions without precats... And by having the main cat still in place you should pass the sniffer too.

Aren't the precats just there to remove nox quicker at start up? On start up my exhaust will smell like I don't have a cat until about 2 mins of warming up... Then After the o2's start reading 14.7 i get some condensation and a almost no Unburnt gas smell out the exhaust

foodmanry

iTrader: (15)

You should be able to pass emission sniffer tests with a y-pipe. I mean should as in theoretically. On my 2k I had a y-pipe for almost 200,000 miles. Then three years ago I started having problems passing the emission sniffer test for California. The first test was high on Nox...like REALLY high. I ended up replacing all of the EGR parts initially and second test still HIGH on Nox. The shop ended up replacing my main cat and third test still did not pass. I had the shop reinstall my stock y-pipe and the fourth test the care finally passed, although not by much.

Fast forward to 4 months ago when I was due for emissions testing again. I was scared I wasn't going to pass so I ran the fuel low and added denatured alcohol. This worked like a charm in dropping my Nox emissions like a rock, but my CO and HC went up a bit barely passing.

I think there is some underlying issue with my car and emissions, but I can't figure it out. I've been through everything on the car and it's showing no SES light, and I mean been through/replaced EVERYTHING.

At any rate...with a y-pipe you likely just need to make sure the car is warmed up for emissions sniffer test. Every car seems to be different, but it appears the majority with a y-pipe and cali emissions pass the sniffer test. Mine passed the first 4 tests just fine.

2kMaxim

Im not sure what the pre cats are there for BUT, I know that when my bank 2 one went bad it threw a cel. So I know OBD2 is at least monitoring some of those 02 sensors. The question is, how does it monitor the rear two in the precat (Bank 1). Heres a photo of the specific model of warpspeed Y Im looking at:

http://www.ebay.com/itm/WARPSPEED-20...7e8592&vxp=mtr


Keep in mind, its not passing the pipe sniffer Im worried about...almost all the places in GA use a direct OBD2 monitor that plugs in.......isnt the pipe sniffer oldschool? Im worried about throwing a CEL. BUT let me know what you guys think.

I think the guys at warpspeed have figured out a way to bypass bank 1 Now that I look at it...it looks like they have the bank one "heat sensing" sensor located up behind the bank 2 precat....so both downstream sensors will read OK because the one precat is being monitored twice...LOL. Thats pretty clever...thus allowing the rear precat and nasty exhaust routing to be eliminated. HMMMMMM! Not to mention i have a BRAND NEW Walker bank 2 precat I just did with a new o2 sensor. This might have been a match made in heaven.



There we go.

03GLEmaxima

I haven't seen many 5th gen dynos but you can definitely tell when that VIAS kicks in

2kMaxim

I was wondering WTF that was...I figured it was the dyno tech backing off the throttle so it wouldnt downshift...i know it downshifted a couple of times and we had to do another pull. Your idea makes way more sense!

Rods03Max619

iTrader: (5)

Look in the Dyno Section, where they post...

2kMaxim

Wait till my VTEC kicks in yo


*On a side note if you guys get the chance...see my thread about Ypipe sound*

NmexMAX

iTrader: (22)

That's pretty rich, IMO. But very consistent. Get a y-pipe, it wont be very loud, especially with the stock muffler. Personally,I'd go with some affordable headers, like OBX or find some used Cattmans in the classifieds like me.

Looks as if you're well on your way, just need to ask yourself how much you want to spend. The info is out there on how to make power on these engines, just how far do you want to go, that's usually proportional to the depth of your pockets.

carsnwomen91

Definitely an underlying issue. Before tuning I couldn't even get a reading cause it kept sputtering but After 30 mins of some quick n dirty street tuning, my readings were so low the tech was extremely surprised... I'd even pass emissions the new way (if I didn't have cel for an auto ecu in a manual lol)

NmexMAX

iTrader: (22)

True dat, sloppy was fairly modified and wasn't that high near stock, andw as slightly above even with his modifications.

http://forums.maxima.org/dyno-slips-...1-ae-auto.html

2kMaxim

Im sort of worried because my torque is nice n juicy and my peak HP is a little low......If i get this YPIPE (which Im probably going to) im thinking it will bump my HP but might really hurt my torque. Im proud of my 194.5 torque

Would you guys say Ypipe first then VAFC...in order of biggest gains?

Also me thinks I might have the VAFC click into the variable mode aright around 3 instead of 3.5ish......would help from a dig maybe.....

MoncefA33

iTrader: (6)

It won't hurt your torque. Don't get a VAFC, buy a SAFC.

But you should buy headers instead of a Y pipe.

2kMaxim

Why would I choose to not be able to control my variable intake?

Headers will surely require a bunch of o2 sims and splicing. Not so with the Y

D Moolah

iTrader: (1)

I was going to say, a VAFC for his car is perfect for adjusting when his VIAS opens...and also on his car, most HP gains come from replacing the Y-Pipe, whereas the 3.5 gains the most from replacing headers. Just pull the trigger on a y pipe and then wonder why you ever waited so long. Y pipe will NOT hurt your torque

2kMaxim

...Would have been the first mod i did had i done the research and found out it wouldnt throw a code on the cali model.

My end goal is to try to reach the whp/trq of a stock 5.5 gen auto. Which I guess is around 205whp. IF possible I'd LOVE to put down what a stock 5.5 Manual does. I guess somewhere in the 215 ballpark? That would be sick. But also a stretch for HP..Maybe I can get the torque there.....