PlanoSER

Please Help provide feedback or possible solutions for this. Here is the vehicle/mods info. Upfront I want to mention I swapped a low miles (21K) junkyard motor that was sold to me as being from a 6th gen. I have reason to believe it may have actually been a Quest motor if that makes any difference. I did a compression check last night and pulled around 215 across the board (lowest 200, highest 220psi)

2002 6MT: Place Racing CAI / Cattman Headers / 2.5" Y-Cutout / Stock Exhaust / UDP / NWP IM Spacers / Exedy OEM Clutch / 6Gen 6MT Trans / 18" SSR Comp_C Wheels.

I went to dyno my car w/ the above mods on it -- it is very hot today. I went to a domestic shop called HPP - they were pretty friendly, however could not? (or were not willing to?) pull my RPM signal so my dynos have the MPH on the bottom axis (sorry guys.) They also said they couldn't provide the runfiles (I found all this out ofcourse after the car was strapped down..) I had them dyno in 4th gear.

Anyways I went in hoping to possibly hit 240whp? You are about to find out the disappointment I felt.
Here first is a screen shot from wunderground of the weather stats:



I first dynoed 2 runs with the cutout closed, running from cattman headers to straight through pipe to the stock exhaust system. On the third run I crawled under the car and removed the cut-out plate which dumps out right after the headers. Here you see the STD charts comparing the closed cut-out vs open cutout. It gained roughly 7whp throughout the RPM band. 214whp vs 221whp:



Here you will see a chart with the STD#s of the exhaust closed w/ the Air Fuel readings at the bottom (214.2 whp.) The dyno op mentioned my A/F ratios looked good to him and didn't really need a whole lot of tuning - he said it was pretty flat 12.6-12.8 range through the topend.



And finally, here is a chart w/ the SAE #s comparing the closed exhaust 210.1 whp SAE vs Open cutout 217whp SAE.



This is really disappointing to me and I am looking for answers as to why the #'s were so poor. Do the HP curves look like the VIAS is functioning properly?? My freaking stock Altima 3.5 5spd with a K&N flatpanel put down 214whp (at a different shop.)

QNO_A32

iTrader: (7)

well the quest come with 240hp/242tq. so youre down 15bhp already....

Grand_hustle17

iTrader: (22)

that is true

rroderiques77

iTrader: (45)

What kind of dyno is this? Those numbers are way too low in accordance to your mods.

Runfiles would have been nice.

PlanoSER

I'm not 100% certain it is a quest motor b/c when I bought it they advertised it as an '05 6th gen Maxima engine. I just have reason to believe it might be a quest motor instead due to the position of the notch for teh crank position sensor on the upper oil pan not matching up w/ my trans when I swapped the motor in. ( had to swap upper oil pans over from old motor )

Even if it is a quest motor we all know Nissan's HP ratings for the VQ35DE lineup are a mystery at best. See: Reference at end of first post to my stock Altima dyno #'s which is also rated at 240hp from Nissan..

Thanks for your valuable input


I pulled this from the dynojet website for this shop:
High Powered Performance Racing LLC
Model 248x

PulsarGTS

iTrader: (6)

I dont think the VIAS is functioning properly. It would be easier to tell if the screen shots were in rpm. It looks like it never comes off the lowend runners.

Grand_hustle17

iTrader: (22)

why thank you

MIK3

iTrader: (12)

I'm guessing a mustang dyno (which might be the first problem) judging by the site.

t6378tp

iTrader: (69)

I would not worry the only real go fast mod you have is a cai and headers but nothing to tune it with

if you want to compare then dyno the cars on the same dyno machine

m_turner_02

iTrader: (3)

don't really understand, but the altima is rated at 250hp and 250tq...damn near the same as the max. shouldn't all fwd vq35de's be rated the same? the only way to tell if you are low compared to others with comparable mods is to have someone else strap up to the same dyno that has also been dyno'd at another place and produced more "normal" numbers. it is a dyno, and it is not the end-all be-all for how much power you are putting out....it should be used for tuning purposes only. go get tuned and get back on the same dyno and see what your gains are

mist max2000

iTrader: (16)

if it is your VIAS,... maybe try to buy a block off plate.. and see what kind of difference that makes... IIRC.. they are on sale till midnight tonight...i say try another dyno... one that will give you runfiles and RPM . . .or take it to the track and see what you are trapping

PlanoSER

I posted this information above already: Dynojet 248x

I thought tuning might help too, but the A/F actually looked pretty solid and the dyno op agreed. It was around 12.6-12.8 through the upper RPMs. Do you think leaning it out a few points would make a drastic difference???

'02 Altima was rated 240hp. And I agree dyno is mostly used for tuning purposes but I wanted to see how healthy the new motor was. Guess the track will be the real indicator :P

Funny you say that mist, when I got home I was so mad I removed the VIAS valve and installed a blockoff plate that my brother made for me awhile back. I agree with above though, if I get dynoed again it will be at another facility that will provide run files and pull the rpm signal. I was supposed to goto a dynoday for only 35 bux but it got cancelled 30 mins before go time. I was upset b/c I rushed to put the NWPz and UDP on that morning and wanted to see some #s so went to this HPP shop instead, paid $60 to go home heartbroken lol.

The old motor was running high 13's at 101.X in August last year and that was without the NWP spacers on it.. I never had any dyno #s on that setup to compare this to. I guess I will just need to bring this one to the track and see what she runs.. The old motor is going into another members 4th gen -- The dyno results yesterday made me wish I kept it instead lol.

jkpgt96

ok well te temp on the dyno is not helping, but the dyno op should be able to account for that some.

12.6-12.8 is too fat for na. typically shoot for 13.5 for a simple bolt-on n/a car, but this is not gonna give you the power you are searching for. Soomething seems off though, b/c i made 214/233 bone stock in mine. However, i agree with others hit the track and find out how it runs..

PulsarGTS

iTrader: (6)

12.8 is typically where vq35s make the most power. If he is running the OEM cat he may have to tune higher as is will through off the readings. Its even possible the maf could be bad, not likely but possible.

PlanoSER

Stock cat is gone, and I have a spare MAF I can try.. it doesnt run like the maf is bad it feels smooth...the o2 sensors are originals with over 120k however judging by the a/f ratio they seem to be functioning fine. For some reason I think the timing must be low but don't know how to measure. My friend w/ a Titan has that uprev/osiris ecu he said he may be able to plug into my car and pull some readings for me.
I'm going to try to play w/ the GTimer I have today to get some #'s with that till I can get to a real track. The heat is pretty high though so I'm sure that will play a factor as well..

PulsarGTS

iTrader: (6)

True Im sure the heat had something to do with it. I personally wont even push my car hard once its over 85*.

PlanoSER

So, I took her to the track today -- 1/4 mile dallasraceway.com in crandall, tx. Weather was 97F and 29.35 barometric pressure per wunderground.com -- DA calculated to over 3700ft.
Even w/ the weather I was immediately disappointed w/ my first 2 runs:
both were 14.6 @ 94mph -- WEAK, guess the Dyno didn't lie.. sorry I left the timeslips in the car but can scan them in tomorrow.

I then reset the ECU w/ the ignition/gas pedal trick and ran a 14.5 @ 95mph

After that I let the car cool off a bit and pulled the plate off the exhaust cutout which dumps right after the headers.

From there I immediately ran 14.2's at 97mph. After a few more runs I began to realize the power feels like it drops alot after 6K RPM so I started shifting at 6K instead of taking it to fuel-cut.. I eventually hit a few 14.1's and trapspeeds were in the 98mphs.

Still very disappointing to me considering the old motor was hitting 13.9s @ 101.X last summer without the cutout or nwp spacers... I think the DA was worse today though for what that's worth.

A guy with a Jeep SRT8 was impressed w/ my car?? and came over to talk to me about it for awhile. He was doing 13.5's and 100-101mph -- he told me his traps and ETs were off by a few tenths and a couple mph today (again for what thats worth) He even asked me to run.. I'll post that timeslip tomorrow too, but he crossed the line by about 3-4 carlengths ahead of me and said I surprised him w/ the amount I gained after opening the cut out.
There was also a guy he was talking to with a 6spd GTO with intake/exhaust running mid 13's and 100-101mph also. (not sure what they normally run/trap)

So, initially I felt horrible about the times but worked my way down from 14.6's to 14.1's and gained traps from 94 to 98mph along the way. I think something is holding my timing back causing the power loss. I am going to relocate the knock sensor/ground it (which I did on my old motor, but currently have in stock place on the new motor)

Any feed back guys? Like I said, I'll post the timeslips tomorrow.

jkpgt96

Honestly, that doesn't sound too bad considering the DA for your runs..The DA on my passes were ~2200 and I made basically the same power you did and only trapped 99.77 so..

You need to get tuned, I bet that makes a WORLD of difference..

PlanoSER

Thx man, I'm still going to redyno at a different shop thats running a $35 special in a few weeks just to see.. I know the weather isn't doing any favors, but still feel my #s (both dyno and track) should be better compared to my #'s last year w/ less mods. . .

Juiced SE-R

13.5 is still spiking just a tad bit high for the VQ's..


You are correct sir. But that doesn't go for every car because we all know every car is diffrent. My car is tuned around 13.1-13.3 on motor and then it drops to 12.8's & 9's above 5k rpms..

Nice times Plano I know your disappointed with your dyno results but those numbers aren't to bad at all man. My guess is your car is running pretty fat. Do you have anything to tune the car with? I just went through the whole header spill and tuning and the headers made mine run pretty rich.. My afrs were in the high 11's and low 12's on motor and it dropped to 10.1's on the spray so it def threw my tune off on my SAFCII from my previous tune but maybe your car is running pretty rich who knows? Def hope its not lean! And def go to a diffrent dyno to see if that was the issue and I know the weather isn't our best friend right now in the south haha, it def sucks cuz I tuned mine myself on the dyno last thursday and it was pretty warm! But keep your head up bro I'm sure a diffrent dyno and a tune will put a smile back on your face..

jkpgt96

Hmm..just odd. I know every car is different, but an n/a v6 vs. n/a v6 being almost a point apart to make power seems odd, but I wouldn't really know on the VQ..now I do. My car is tuned 13.3-13.6 tapering to 13.1-13.0 above 6000rpm.

PulsarGTS

iTrader: (6)

Considering the conditions not bad times at all. I wouldn't think you car is really down on power if it wasn't from the times of your previous engine. But were those times in similar conditions?

97Maximus

iTrader: (18)

where is going to take place.. for that much ill jump in.. do they offer runfiles and rpm signal?

thats great! nothing wrong with that tune..

NmexMAX

iTrader: (22)

I'm pretty sure you can call them up and have them send you the runfiles. Try that and post them. VIAS doesn't seem to be functioning properly. Get your friend to get some data via his Cipher. Most namely timing & maybe some MAF flow #'s with respect to RPM.

jkpgt96

Thanks..that was on the Probe of course.

PlanoSER

I wasn't sure either about VIAS functioning so I put the VIAS block off plate on before I ran at the track -- those times were w/ VIAS block off plate for what it's worth.. Still seems very slow IMO.

old motor with cai,headers, udp was 13.9 @ 101 -- roughly 2200ft DA that day.

new motor w/ cai, headers, udp, nwp spacers, and block off plate was 14.6 @ 94 then 14.1 @ 98 with exhaust dumped after header. -- roughly 3800ft DA.

I'm going to try to bug my friend to get some cipher logs for me this week and will post those as well as runfiles if I can get that shop to email them to me..

Not sure i'm a fan of the block off plate, I may try to put the VIAS back..

Juiced SE-R

Matt are you still planning on running Friday night?

NmexMAX

iTrader: (22)

What about the dyno? Was the block off plate there w/ said dyno?

PlanoSER

Yes, so far still plan on running Friday. I need to relocate/ground my knock sensor like I had it setup on old motor I feel this may be the key to getting the #'s back on track.

No, on the dyno the IM was in stock form w/ VIAS hooked up; the only mod to IM was the NWP spacers. . I removed the VIAS valve and installed the block-off plate after I got home from the dyno and ran it the following day at the track w/ plate installed..

Juiced SE-R

Well I hope thats the problem. Good luck getting that problem fixed..

MIK3

iTrader: (12)

Do you plan on relocating it to where it would still be functional? I plan on doing this but am not sure on optimal points so that it'll still function properly.

PlanoSER

Not particularly. The way I had it before was KS wrapped in a rag and ziptied under a coolant line above and to the left of the shift linkages.. I connected a wire to the bolt that runs through the hole in the KS and a washer & nut on the other end to hold the wire on. Then ran the wire to the chassis for ground. Who knows if it even had a positive effect or not but I'm going to redo it this way tomorrow and see if I feel any difference... I'm going to the track again this Friday & will run it this way.

NmexMAX

iTrader: (22)

That dyno shows a vehicle w/o a functioning VIAS.

PlanoSER

I had the same feeling, that's why I took the VIAS valve out and put the block-off plate on before going to the track on Sunday. However... my track#s were pitiful.

old motor last August: CAI/Headers/Pulley/Grounded_KS/Stock Exhaust - 13.9s @ 101
new motor this June: CAI/Headers/Pulley/NWPs/BlockoffPlate/Stock Exhaust - 14.6s @ 94
then Open the cutout - 14.1s @ 98

I went back and checked, the DA between the 13.9s last year and the 14.6's this year was about a 1000ft difference. I dont think a 1000ft DA difference is going to drop traps from 101 to 94mph on a car that has more mods??? Keep in mind when I ran 14.1s @ 98 on Sunday thats with the exhaust dumped after the headers which I did not have last year on the 13s runs.

PlanoSER

So, I relocated the KS --> bolted/grounded it to the chassis instead where the old battery tray used to be (batt is now in trunk.)

I took her for a spin and here are my findings (take note this is with the cutout closed, and exhaust flowing out through the stock catback system)

Roll into 1st gear.. about 3K+ its breaking the tires loose/chirping/spinning.. at redline I grab 2nd quickly and it is now trying to DESTROY the tires, spinning so bad!

The car has not done this since I can last remember. The only thing I changed on the car was the grounding of the KS, so unless there is some freak high pressure front blowing in or something else, this has to be the difference maker. **I checked wunderground.com and it is currently 91.7F and 29.8 Barometric Pressure so that obviously isnt doing the car any favors.

The sound of the intake has also changed and I also now hear a new sound I havn't before -- it is almost like the sound of the air rushing through the intake & manifold when throttle is full @ upper RPMS.

I was so happy I almost drove straight over to the same dyno place to see whatup lol. Not sure I want to eat another $63 to redyno it right now b/c I'm going to the track tomorrow. I may just let the timeslips do the talking to see if the #'s backup the difference i'm feeling or if its all in my head..

mist max2000

iTrader: (16)

you think you could take some pics for me of how yuo rigged up your KS ? ,..im glad you might of fixed your problem.. com on 13.7 lol

PlanoSER

Yeah I got one on my cell phone ill email it in and attach it somewhere. My dyno charts on the first post arent showing up anymore for some reason? yet they show up on the maxima.org album when I check? Maybe I need to relink them, gimme a min i'll post a pic of the KS

EDIT: Here it is, bolted to the bracket in front of driver side motor mount -- the battery tray is usually on this location:

MIK3

iTrader: (12)

Did you notice any visual defects on the KS itself (corrosion, cracking) or on the wiring? Might have been doing some stupid low retarding?

tookrzy4u192

iTrader: (19)

glad its running better now that you relocated it.. can't wait to see it run tomorrow

PlanoSER

No, the wiring and sensor appeared to be fine. I *did* have an issue several months ago where the car ran seriously crappy w/ lots of hesitation and I discovered the harness was messed up -- one of the wires had pulled out/disconnected. At that point I chopped the harness connector and just direct-soldered the wires and they have been holding up since.. Apparently the car just runs better w/ the KS relocated/grounded elsewhere.

Thanks man, hopefully the #'s will show improvement Have a safe trip on the way down to "Big_D"