Well I finally got my car finished and took it to the dyno. It put down 212 hp and 203 tq. Better than I was expecting with what I have done to it.

I have the following performance modifications:
pop charger
MEVI
Cattman headers
High flow cat
catback exhaust
Apexi VAFC II
JWT valve springs
Quaife LSD
suspension
*EDIT*
forgot a few things, sorry!
5 lb flywheel
Definitive UDP
Exedy stage I clutch

 

Can I get this put in the moderated section?
*EDIT* nevermind I read the sticky.

 

I want your headers!!!!....nice numbers

 

thats pretty sick..

 

All this power without an ECU? Very impressive indeed...

 

Good stuff!!!!

 

Nice numbers!! I'd be extremely happy with those numbers and no ECU.

 

Post the run file so we can compare.

 

woah, i'm extremely jealous. I want my car to put down those numbers N/A.

 

AWESOME #'s man that is the most i have ever seen on a NA 4th gen

 

Damn good numbers. Congrats.

 

how come you have Valve springs and no cams?

 

I couldn't afford the cams and I autocross anyway so I didn't want the low end loss. I did however atleast want to put something that will help guard valve float with an extended rev limiter. And since I was doing a full rebuild anyway I figured I should install them while I had the engine apart. SR20DEN, I willl post it later on today or I can e-mail you them aswell.

 

Wow, and no ECU, I wonder what you would run in the 1/4, nice #'s man. Do you have any prior dynos to compare?

Wow that is amazing, didnt iron lung put down 212 w/ cams and open headers -no MEVI?

That's a cool engine we got here.

What tuning did you perform for a/f ratios,
Anyway, Congrats on the most HP n/a 4gMax I know of!!!!

 

I haven't seen any cars that are performing well with those JWT cams anyway. You did yourself a favor by not buying them.

 

your #'s are awesome espically considering you have no ECU. i assume your redline is still 6500rpm since you have no ecu and also from looking at the graph. i take it that MEVI and no ecu is not such a bad thing since you have so much TQ. How had was it to tune using the VAFC and also how difficult is it to control the MEVI with VAFC. nice job

 

When I put the MEVI on I did lose torque. I have all of my pre MEVI and post MEVI dyno's as well as pre rebuild and post rebuild dyno's. I did however write this post in a rush and my friend so nicely pointed out to me that I left out my exedy stage one clutch and my 5lb flywheel aswell as my definitive underdrive pulley. I am sorry about that I will correct my post.

The VAFC II was really easy to tune. I actually had a post about it and was supposed to put a write up about it but I got activated and was away from the org for almost a year. I will tyr to get that done soon.
I will post my air fuel ratio tomorrow aswell. It is almost a straight 14 except for a few places where it dips to 13.8. I am worried about summer time and detonation occuring if it gets to hot so I may go a little more conservative in the summer.

 

sounds good the more info you can share the better. its really nice to see a NA 98 maxima with that kinda power especially because 98 and 99's really have no ECU option or anyway to raise the REV limit to take advantage of the VI power but i noticed you retained a ton of torque. Just wondering why did you rebuild the motor? was something wrong. 13.8 is really lean and i know 14:1 is ideal but i would be scared to run that. but obviously that combo makes the power. if you could share any experience you had with tuning the VI with the VAFC it would be really helpfuly. i was going to get the SAFC but now i think VAFC is the way to go. what is involved with turning on the Vi with the VAfc is the rpm switch still needed?

 

13.8 isn't lean.

14.7:1 is stochiometric.

Above that is lean.

Below that is rich.

 

Dude. He has an engineering degree. You MUST be incorrect sir!

 

zack342, I rebuilt my motor because a butterfly valve screw came loose and was sucked down my intake manifold and embedded in my cylinder head by my piston. I have replaced all of my pistons boring the cylinders 10 over and replaced all of the bearings and done a standard valve job. I am also using ARP head studs. Anything below 14:7 is rich like SR20DEN said but it would be dangerous to run any leaner than 14.3:1 in my own opinion.

The rpm switch is not needed with the VAFC II

 

IMO, 13.5:1 is good for short run (drag) NA settings at high rpm . However I would tune richer than that (12.5:1) if I was going to run some type of long road race. Even that can build some pretty crazy EGTs.

 

thanks sr20den and thank you Jeff for doing what you do best..........nothing

Jeff i am a Mechanical Engineer not an automotive expert...notice how sr20den was nice enough to correct me without any comment that is demeaning or rude. i swear some of the guys in here are brutal you ask the wrong question and you get a** handed to you.

SLC98Max do you think you over bore and valve job may have accounted for any of the extra power. in any event great #'s think kinda showed me which direction i need to go.

 

Anytime you want to compare posts, let me know

 

Those are some pretty strong numbers. I noticed you're in Utah so I'm guessing your dyno had a pretty significant correction factor for altitude? Something like 1.05+ CF? What kind of dyno was this? Dynojet? Dynapack? Mustang?

Also, are you using a midpipe or is the stock intake resonator in place?

 

i think it was dynojet research from lookin at the graph posted

 

I am using a resonator. I remember you posting about a year ago about believing the stock resonator flowed better and I have been meaning to try switching them on the dyno. I have to pay $130 an hour for dyno use so I try not to go frequently. There are only two dyno's in salt lake and only one lets you be with your car for the run.

The dyno was a dynojet. I beleive it is 248 but I will check. I will check what the correction factor is on this dyno run when I get home but I am sure it is high. I need somewhere to host my dyno file so I can post it.

SR20DEN, if you still want it I will e-mail it to you but I need your e-mail address.

I was surprised by the numbers aswell but all of my previous numbers have been leading up to this with each modification. It was a third gear pull like all of my others. Also the engine was just rebuilt by me with everything new including the timing chain which is prone to stretch and alter valve timing with age so this is a fresh engine with high compression (not high ratio just very little blow by) as I had them bore out the cylinder 10 over and use tight clearances. The engine was also balanced and I had a three angle valve job done although this is the same as stock so neither of these should affect power output.

I will dyno again next week with my JWT ecu to see if my VAFC II causes it to pull timing and see what I get and I will post that dyno as well.

 

Sweet deal, man. That resonator really seems to do wonders for the VQ in terms of consistent rev range power and driveability. What I notice most is how much smoother the VQ runs, especially thru the gas pedal and clutch. With a midpipe there is more vibration thru these pedals.

I really wouldn't bother swapping it out because your power looks good and solid.

 

If I'm not mistaken this is probably the first N/A 4th gen motor with actual internal work done. 3 angle valve job and overbored. Cool.

 

Are stock sized pistons still used and i wonder if the head work helped that much?

 

I believe ironlung put down 215whp at 6500ropm with the curve still going up with the jwt cams.
The cams make good top end power but heavy maximas are not well suited for the low end loss especially ones with mevi's.
The nismo 262 I and 262 E look good

 

Dan- call me when you get ur phone working. I'm getting my ecu soon and also need to get a boost silenoid for the vi (checked it and it was bad) so once we get that done, we'll dyno our cars together. So wait for me before you go dyno yours with the new ecu.
Justin

 

Sorry I didn't get back to you on sunday. My GF hit a deer with my car and I ended up not getting home until really late. Blown agx and some bumper damage. Also my exhaust was bent slightly. I will give you a call later tonight.

 

I'll look at it tonight. Damit always something wrong with your car. Call me.

 

Excellent #s! I miss the VQ sometimes

 

Nice numbers SLC98Max!!! No JWT ECU either! You should see if Technosquare has an ECU for you... that should help you even more since some guys say that is more aggressively tuned than the JWT!

One question about the JWT springs - when you did your rebuild, is that all you replaced? What did it cost you for the rebuild if you don't mind me asking.

My motor has been burning oil for a while, but compression is okay for now... but if it goes south fast, I might look into a rebuild. If so, I am also considering the option of getting a second motor and building that on the side and slap my mods on and swap.