Hello guys..........ok I just raced a 427 Cobra Jet, my neighbor and he got me by about one car length, he did have the jump out of the hole and he runs in the mid to upper 12's in the qrt. I must go faster!

Question:

My baseline dyno is 333rwhp......my A/F is very conservative and low 10's in the upper rpm band. What would be required as far as tuning to be near 370rwhp? That is the question for you.

A/F adjustments to 11.4:1 across the board and slight timing?

Please give input on tuning requirements to acheive 370rwhp, but engine reliability is very important to me.


THXS!

FluidZ

 

Anyone?

 

Uhm, well I love you fluidz but my mom dropped me on my head as a child and so I'm not that bright

 

fuel pump and injectors.......up the boost with some pulleys.......plenum.........cool down that intercooler.........have you gone to see Henry yet?.......he might have some ideas too

 

fluidz, my recommendation is to gradually increase timing retard starting at 1 degree at say 3500 rpms up to 6 degrees or so at redline.

As for A/F ratio, you'll have higher numbers in between the 500 rpm increments due to the SS box. If you keep those A/F sinusoidal peaks in the high 11s above 6000 rpms and very low 12s between 5000 and 6000 you will fine, in my opinion, so long as you're taking out timing.

But that's just my opinion--based on 4000 miles of daily driving with many WOTs to redline every day.

Keep the belts properly tightened, retard the timing, and keep a regular eye on that A/F ratio.

--Steve

 

after reviewing ENTHUZD SS Box modified map set to 393rwhp on 93 octane gas...........his timing map was set at .5 degrees retarted at 4,500rpm, 1 degree from 5,000-5,999 and 5.5 degrees at 6,000 through redline. Sounds very aggresive to me and I dont have big enough balz to do that.......

 

help me understand then.....

if you retard the timing, you lessen it, which causes a richer a to f mixture, right??

ifso, would'nt this be a safer (therefor not as risky) environment??

es =

 

Fludiz,

Did you plug in and see what the timing map Vortech ships looks like?

 

I am going to tonight.

 

Try running a nitrous spray bar on the intercooler, are you running nismo headers or stock? what do the guys a comptech say? how many lbs of boost are you running?

 

Ok, look. Cooling the intercooler, increasing boost, adding headers and such are all good advice. But first things first. I would estimate that a custom tune of the SS box will add a good 40 HP to your numbers.

Looking at the dyno sheet you've posted where it shows A/F versus RPMs versus boost, it's obvious that you are running too rich from 5000 rpms on up. But you're also running more rich than necessary from 2000 rpms to 4000 rpms. There's no reason the A/F ratio needs to be in the low 11s in that range.

Also, if the R4 software doesn't show 8 psi at 6500 rpms, you might want to recheck the tensioning of the serpentine belt. You should be able to just barely turn the belt completely upside down if you twist it. IMO, if you can easily twist it upside down then it's too loose and you're losing boost.

--Steve

 

belt tension is PERFECT, you can turn it 90degress and thats it, PERFECT...........SS Box tune I estimate 380rwhp, this is happening in the next few days................

 

How do you guys know what the A/F is supposed to be in all the RPM ranges ?

 

well I will not be tuning my car for at least 2,000 miles. This is advise from my tuner, COMPTECH USA...........they mentioned and confirmed the 350Z has multiple maps in the ECU and that my car is very very safe as it is right now and want me to hold off for at least 2,000 miles before I tune her to make sure nothing funky goes on if my car swithes to a leaner map.......they also mentioned the safest way to acheive higher HP safely is to tune it slowely over a period of time.

COMPTECH USA......former contract race engine builder for Honda Motorsports international, I think I will listen to there advise. Even the WELL KNOWN HERNY down at MOTORSPORT DYNAMICS in Sacramento,CA stresses his concerns with the 350Z ECU multiple map issue.

Tuned to the optimal point of power is great, but if the stock ECU remaps something a little lean, kaboomo.......that is the unknown issue at this point in the new 350Z short life. ENGINE MANAGEMENT is the MAJOR problem and the UNKNOWN POSSIBLE KILLER of our motors at optimal high HP tuning.

I beleive anybody can yeild super high HP numbers today, the question is who can reliably yeild high HP numbers today and still be driving the car a year or two from now and 20,000 miles down the road?

That is the truth, the whole truth, nothing but the truth and I'm stick'in to it.

 

Fluidz... this probably is pretty decent advise, but I think you have some room to play right now. I'd see if they will dial it in a little better with a plan to revisit them in 2000 miles. As I recall you were running 333rwhp at the moment. You should be safe with a tune that will give you 360hp or so. Later, you can go back for as much as possible.

Of course, my feeling is if the install is done well and the tuner is competent, you should be able to tweak it all the way as soon as the kit is in. I've got 800 miles on my install (400 miles at the fully tuned 420hp level) and have had no issues with fuel or timing whatsoever. Driving it to Nashville next weekend so I will give a full report when I return. I should have around 2000 miles on the SC by then.

 

mcduck, what other mods do you have other than the Vortech?

Thanks man,
-Brian

 

If you haven't already done it, get yourself a wideband A/F gauge like the AEM UEGO A/F gauge so you know when something goes out of wack.. EGT will help too..

Don't go cheap on the gauges.. they may save your motor one day.

--mike

 

I agree with everything said here. As you know, the main reason your numbers are low is you are running uncessarily rich almost everywhere. I would shoot for 12.5 to 11.5 across the board. That alone should get you well over 350hp, and still leave you sufficiently rich to avoid detonation...especially at the higher RPM's.

 

Actually the main reason the hp is under 350rwhp is because of the timing being sucked out. The A/F being a tad rich dosent help but I really think the biggest hold back is the timing being retarded, its needed but how much is needed is the hard part to deal with when it comes to bed time.

 

AEM UEGO A/F - have one.