running pig rich w/o AFR tuning.

rather disappointed in the numbers.

My friend dynoed his stock 2001 5-speed with 173 whp compared to my 199.98.

 

fully bolted, meaning what exactly? also, you are running super rich! you have to deal with that issue before you will start seeing good #'s! your hitting 10:1 at 6K? and 11:1 at 5K (even at 4K your at 12:1, a typical rich range for boosted maximas)...those are all too rich for a lot of boosted guys! take into consideration that your buddy is stock, so his AFR is probably still very good ie. around 13.5:1 across the board or so...ie. he is getting all the power that is there to be had...

never seen a stock bolt on maxima run so rich before without upgraded injectors added! you will gain a lot from A/F tuning...

to give you an idea where you should be @ if we are talking about absolutely every bolt on...the de-k is capable of 210-220whp with A/F dialed in...230-240whp with emanage ultimate (heavy ignition timing increase)...

 

What type of DYNO machine did you use? Also, a list of mods would be cool for comparison reasons.

 

I see nothing wrong with the numbers.

 

I still have not seen a DEK lay down more than 210 (Dandy's isn't a DEK) Also, I wouldn't go that far and say stock a/f would be 13.5 either.

IIRC, he doesn't have VIAS

My A33B shows leaner results when adding an intake.

 

dandy max's is essentially a de-k...what's the difference? he has the 00VI....! yes cams on the regular vq's are slightly better, but aren't huge...

and to your other point, you haven't seen any of them lay down more than 210 cause none of them have had the ability to tune it properly since there is no ecu upgrade for these engines...only now has the emanage ultimate been avaliable--no de-k's with it that I know of to date...then I have no doubt #'s just like dandy's max's will be possible 230whp or so...
you have to think about this, maxboost put down 199whp without no timing advance, and no air fuel tuning, in fact he put it down with an almost 10:1 air fuel ratio...

also, you can't compare the a33b, the 3.5L has entirely different air fuel ratios iirc...

 

Why would it(A33B) have entirely different afr's?

 

what I mean is the 3.5 typically has entirely different afr's after adding things like headers and other bolt-ons than the 3.0's do...so you can't compare how one engine deals with changes or gains from a/f tuning and mods as some respond better than others and or produce slightly more power at a different afr than another...case and point, the 3.5's after headers need a good deal of afr tuning to see major gains, which they certainly do, but 3.5's don't seem to gain much from advanced IG timing, whereas historically, 3.0's have been the other way around...a/f tuning doesn't net them as much as IG timing advance does...it all has to do with the differences in volumetric efficiencies at different rpm ranges of each engine and which one can effectively use more timing or air or fuel at a certain location with knocking due to the VE being to higher or lower in that range than another.

 

Yup, I don't have VIAS

does this mean I don't need fuel management when I supercharge this summer?

 

Check my homepage for mods:

www.dsrmotorsports.cjb.net

 

I was talking about dandymax that has the vias...

 

your homepage says you have timing advanced by 17 degrees. is this correct (what unit are you using to do so)? if thats the case, i can see you dissappointment in the numbers.

also when you say you don't have VAIS, i assume you mean you don't have the VAIS control installed, and that you dynoed with the VAIS control rod in the open position.

just trying to take the bits and pieces from this thread and put them together
cause it's kinda hard to follow.

 

My timing was advanced by a Nissan Consult II machine at the dealer. It's different on a 5th gen bedcause the timing change stays in place compared to a 4th gen.

I took the whole 00VI rod out of my intake manifold so that my curve is linear compared to the "VTEC" like VIAS (also to assure myself that I am getting every bit of power I can since my VIAS was broken already)

 

regarding the timing, understood...

as far as removing the control rod, never heard of that before so i'm curious. so basically you have a gutted 00vi (no moving parts within the manifold)? did this hurt your low end? i'm not too familiar with 5th gen dynoes so it's hard for me to tell just by looking at your dyno sheet.

 

I can change my timing +/- 2* w/ Cipher.

Also, it's BTDC, no 'across the board'.

Typically w/o a tune, I've seen 2 other dynos (aside from yours) that put out ~ the same #'s w/ VIAS rod removed.

What were the SAE #'s? Do you have the run files?

Why did you cut the fun short @ 6k?

 

the timing advance via the consult does not apply at WOT...only during closed loop operation, so on a dyno, the timing advance will not produce higher #'s since the test is typically done at WOT/open loop.

without the rod, other dynoes show about 10whp extra from ~5K and up, but show about 15whp less before that and about the same amount of torque loss until 5K, where the torque band is held flat till redline rather than dropping off...so there is a high end improvement to be had, but someone on here determined that by using the integral of the entire powerband, there was a actually a slight loss since our gears are not close enough to always keep it in that meaty powerband, hence there would be no practical acceleration gain...however, if it is broken and you are sick of fixing it, the best solution is probably to remove it...

here are a collection of graphs I did back in the day from a discussion on this very subject, and some simple math calculations of them to see whether there is a gain or not:

in this photo, there are four graphs, the first (up and left), is a graph of just one guy on here with his de-k that got 220whp after a/f tuning and full bolt ons...the second (up and right) was from a thread about someone with a broken vias and power rod removed, the third (bottom and left) is the torque graph of the same scenario--broken vias vs. power rod removed and the last one, (bottom and right) is of a working vias (although not working the best it seems) overlayed on a dyno of the power rod removed...the last picture is what we are primarily looking at and what all the calculations are based on...all the equations seen there are the regressions of the plotted data--the equations used to plot the graphs using two different methods for accuracy checking...then integrals were used on those functions.

this 2nd picture is some simple math regressions of to graphs on their integrals to see what the gain is like from vias working to power rod removed to see the gain since I was curios of this in the past.
The end result was that there is an overall 9ft.lbs wtq gain if kept above 5K rpms->redline and a overall loss of 18ft. lbs wtq if the entire rpm range is considered from 2.5K->redline.

looking at whp, if the entire rpm range from 2.5K to redline was considered, there is a 7whp gain with the rod removed overall, if kept above 5K, there is a 20whp overall gain

keep in mind these are rough estimations, just took the values at different rpm points from the last "overlay" graph of larry c and nathan...the comparison was almost perfect as told by them, they stated that as far as mods go, they were almost the same (almost potentially taints the data a good deal) and the conditions of the dyno were almost the same (once again, mess up the data little)...

so with the power valve removed, overall you gain 7whp and lose 18ft/lbs wtq going from 2.5K->redline according to the area under the curve/integral of the entire thing minus the other

if kept it above 5K rpms->redline, you gain 20whp and also gain 9ft/lbs wtq overall mind you, not peak...so don't get too excited!

I know larry had an extended rev limiter...didn't use the data past 6.5K of course, and nathan's data only started at 2.5K so I couldn't use larry's data below that to see torque loss.

so the final result on that discussion was determined that the removal of the valve was not optimal for everyday use, the whp gain was offset by the dramatic loss in torque, required to move our heavy cars off the line effectively and get us into that meaty powerband up top sooner.

if you are doing only high end racing though, the power rod removal can be worth it, especially with an extended rev limiter as the line stays steady in high rpms, never dropping. Most likely, though, proper tuning needs to be done to regain some low end and also to gain some high end to a factory ecu that has a static WOT a/f map that is tuned to expect more air below 5K and less air above 5K that the removed power rod effectively does. so tuning and an extended rev limiter are an absolute must if your going to remove the power rod.

 

It applies to anything under 2300 RPM

 

that's the second stipulation/condition...but primarily and most importantly, not at WOT, which is what everyone wants...more timing at WOT...

 

good info!

 

the best thing to do would figure out a way to modify the power rod to optimize flow, so you can balance it to get the best of both worlds! better high end with minimal low end loss...

 

lol, I tell everyone I'm willing to sacrifice all my low-end torque in exchange for high-end HP, That's why I'm going SC instead of a custom turbo setup.

Another orger from SoCal told me theres practically no power in the lower RPM range on a supercharged maxima, you don't hit full boost until 6000rpm.

But whatever, SC is SC, and me wanty.

 

not exactly true, with the much smaller pulley's, boost comes in sooner...since it is spinning at a faster speed at a lower rpm...so with the smallest pulley you see a little boost in the low end...plus does it really matter? our cars always have had a decent amount of low end...even the 3.0's...! it's not like your supercharging a 1.6 or 2.0L honda engine where there is no low end to start with...!

SC is a great way to go, yes less power possible in the end, and you get that parasitic drag from the pulley system, but in the end, with the smallest pulley, all bolt ons and proper tuning, you can confidently see 350whp if not a little more--now tell me that won't be one screamin' maxima regardless if most of the power is in the high end or not....!!??!?!

plus for road racing and track racing, SC is the best...you keep that beautiful NA-like linear powerband...no sudden peak or spool up...

 

Would the power valve removal then in turn benefit an auto? I notice that the auto doesn't hold top end power to well. I mean I need to fully check my Vias, but I'm sure it is working. I can't really see those dyno's but where was the most torque lost with the removal? If its minimal before 2500 then it can be beneficial on an auto? Correct me if I'm wrong? I'm just speculating as I need to verify if my Vias is actually broken or not.

 

Depends on what type of driving you do. i.e., a lot of highway driving would benefit re: the long 4AT ratios.

Also, where did you get this notion that the AT DEK doesn't hold top end power to well?

 

I think he means the gearing is so far spread, that it from one gear to the next, it will shift out of the meaty top end powerband the de-k has...combine that with the fact that a lot of auto's shift out early and don't carry all the way to the limiter, and you can't ride that powerband as long as you'd like and carry higher rpm's into the next gear either...

 

It can also be that the longer gears are beneficial w/ high end power. This has been discussed re: A32 MEVI's, and IMO, it's beneficial when highway driving.

Also, why not hold the gear to fuel cut whenever trying to exploit the powerband? I always do, call it ricey, but do I care. If your power band is useful past stock shift, then why not take advantage and shift @ or near fuel cut?

 

You hit it dead on. The VB is great for low end already but doesn'thit the top end. Ah well, I'll try it out and see how I like it. How do I go about removing the power rod? Is it as simple as opening the Vias up and pulling it out?

 

Well since this got bumped up and I apparently missed it the first time around (I was in NZ), I have a couple things to add/clarify:

-Nmex's point about my last engine not being a DEK but a DE is valid. They are not the same just because of the 00VI. IMO the DEK does not have more aggressive cams. Yes the exhaust has a bit more lift than the DE, but look at the smaller duration on the intake, given that choice I'll take the DE cam thank you. In fact I'd wager that difference is partly responsible for the fact most DEK's don't peak as high in the powerband as mine did 2 years ago (dyno was 220hp at 6600 rpm - sheesh has it already been 2 years!?) The later intake closing will help at high rpm. Now having said that the engine going in the car now for the rest of this season is a DEK out of an 01 but it won't have stock DEK valvetrain.

And speaking of that dyno...

-I had the PV installed and opening at 5000 rpm. So the 220hp is with the PV, not without. I have never dyno'd without a PV installed.

-IMO the 3.5's can benefit from timing advance just as much as 3.0's, both engines are conservatively tuned from the factory.

 

If you're facing the engine from the front of the car, it has to come out from the left side of the manifold IIRC, there's a small metal cover bolted on (just take a look you'll see what I mean).

 

It doesn't help anything with respect to power low , mid or high. Just 'helps' shifts, and @ WOT, depending on shift point/fuel cut, 1-2 happens @ 45-50MPH, 2-3 80-90MPH. So, again, IMO, no relevance re: power.

Now that Dandy has made that point, I think you should leave it in. Though that point is complex re: DEK vs DE. But, if you get ambitious, take it out. Do a simple search re: power rod removal. Honestly it seems as if you're getting deep enough in engine modding that a small donation to the site will be worthwhile at this point. If /when you do, power rod removal in the 5th gen and AM forums. I think I've even linked you in the past.




This is apparent on your dyno, re: torque curve. Very linear and strong.

 

Will definately get around to it. I honestly keep forgetting. Free search only takes you so far lol.

I've been in a power rod removed max and it was amazing on the highway. Low end wasn't bad but it was standard. I'll play with the car bit.

 

+1

More intake duration >>> slightly less exhaust lift, for sure. It's kinda discouraging that more people don't know of these subtle differences between the VQ's.

 

because the subtle differences are so minut...they make such a little difference, most will never care to know about it...


when you remove the power rod you take it out from the passenger side of the engine, the a/c line might get in the way a little, but there should be a metal cap or cover there with two bolts IIRC...easy...but make sure you take off the other side first, the side with the actuator/selenoid since if you take it out without removing the spring from the driver side first that is in there between the rod and the brass actuator cup, it may fall in the manifold, then you would have a big problem and have to remove the entire manifold to get it out...god forbid you run the engine with it in there...and also make sure if you leave the cup assembly on, it is jb welded on there so it doesn't break off and fall in the manifold as well over time...

dandy will have to give us his opinion/experience of b4/after feel with the power rod removed and not...

there has been a few threads on it, you can search for them...I did a mathmatical analysis back in the day but can't find it...


keep in mind that the auto's in many max's have trouble holding till redline in some cases, and shift out early, those far spread ratios will plant you to far down in the next gear as well...so something to think about since, you might still need the midrange and low end that is lost with PV removal...

-Michael

 

Minute or not, it's a difference that is worth noting.

Also:
Both my 4AT's will sit and bounce the limiter no matter what gear (1,2,3, never tried 4th/OD) if left in that particular gear, i.e. holding the gear. No reason the 4AT TCM's in 00-01's should be any different.

 

Cams specs are sort of a big deal, don't ya think? Especially considering that DE intake cams have 8* more duration. That's pretty significant. All else being equal, the DE with 00VI has slightly better top-end power potential than a DE-K. Besides, other than the cams, there are hardly any other internal differences between the DE and DE-K (other than slightly looser bearing clearance specs) so you'd think people would at least know that much. In the SR20 community for instance swapping '91 intake cams in is a common thing even though the difference in spec isn't MASSIVE. Just concerns me how little most people know about the engine they "love". Heck, most people still think that the DE-K has better/lighter internals than the DE.





Ok fine. I'm just a fiend for technical info. Sue me...

 

...extra water outlet on the block...

 

I meant internally, but yea that too.

 

^^^ yep better cooling. But if anyone is throwing in a DE-K should already be considering changing the cams. Preferable to pathfinder on the 3.0 or a set of 3.5 cams.

 

Slow down there. Explain ... again

 

Yeah I just figured since we're listing differences anyways.. lol