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Grey's 3.5 dyno 226hp/202tq - Dynojet in KC

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Old 04-26-2008, 03:09 PM
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Grey's 3.5 dyno 226hp/202tq - Dynojet in KC

Finally got to Revline Racing in KC to a few dyno pulls.

I actually got four - their wideband didn't work the first time. They use their own PLX and probe in your bung, not a sniffer, so more accurate. Evey run was made in third gear, taken to fuel cut, locked into gear by a Shift_Fast. We noticed that the first two pulls had a knee-dip at 6K, so I took off the new air inlet - made no difference. There were no run files available today. All runs were made with open cutout except #4 - notice 7hp decrease...

EDIT: Fuel pressure was 42 psi.

Run #1 printout was also out of ink, so it's dim.... Setting was SAE, smoothing = 5 for all pulls.

Pull #1:



Pull #2:



Pull #3




Pull #4: cutout was closed for this one.




I'm pleased - 226 hp and a decent curve... now let the fun begin..



Some more photos of their shop:

http://i48.photobucket.com/albums/f2...o/DSCN0214.jpg

http://i48.photobucket.com/albums/f2...o/DSCN0213.jpg

http://i48.photobucket.com/albums/f2...o/DSCN0212.jpg

http://i48.photobucket.com/albums/f2...o/DSCN0211.jpg

http://i48.photobucket.com/albums/f2...o/DSCN0210.jpg

http://i48.photobucket.com/albums/f2...o/DSCN0208.jpg

.

Last edited by grey99max; 04-28-2008 at 09:00 AM.
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Old 04-26-2008, 03:33 PM
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Did you have the TQ locked during these dyno pulls?
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Old 04-26-2008, 03:52 PM
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Is the VI working? I believe power should go all the way to the top and not drop like that.
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Old 04-26-2008, 04:07 PM
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2k2 + top end isn’t that great actually.

Grey, you know what I’m going to ask… DRF’s please.

How does that bad boy feel? How do you have the VIAS connected?
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Old 04-26-2008, 08:21 PM
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Originally Posted by streetzlegend
Did you have the TQ locked during these dyno pulls?
Not this time -enough drama just getting these pulls done.... The cutout thing and the intake thing were enough changes for one day.
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Old 04-26-2008, 08:23 PM
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Originally Posted by SonicDust187
Is the VI working? I believe power should go all the way to the top and not drop like that.
There is no VI - the intake has been SSIMed...

There is the same funny dogleg in each graph. ??? Could this have been the dyno? I watched and heard the dyno operator take it to the ECU fuel-cut at 6650 on each pull, but the graph RPMs stopped before that on each graph. I wonder if the DRs on the front were slipping at the top - third gear pull to redline could do that. I've seen other cars do it - even to the extent of making lots of tire smoke.

With the 3" cutout open, the car was really loud... Really loud.

Last edited by grey99max; 04-26-2008 at 08:35 PM.
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Old 04-26-2008, 08:26 PM
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Originally Posted by NmexMAX
2k2 + top end isn’t that great actually.

Grey, you know what I’m going to ask… DRF’s please.

How does that bad boy feel? How do you have the VIAS connected?
Top-end power is plenty - when two stages of nitrous are coming back..

As I said, there were no DRFs available,

How does it feel? It's a beast on the street above 4K. No VIAS - it's SSIMed by *Z350.
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Old 04-26-2008, 09:43 PM
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Harold! w00h00!!!!!!!!!!!!!!

The drop in power after 6k is normal, I have it too. Its a cam-timing issue. Power up there isnt "all that" on the 5.5gens+, and its even more noticeable when using a 3.5 with 3.0 ECU and timing equipment. So no, I doubt your tires were spinning on the drum if they strapped down the car properly.

Yes SSIMs dont really kick-in until 4k.... and you sure as he!! know when it kicks in LOL... especially with BOOST! *hint hint Harold *
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Old 04-27-2008, 12:59 PM
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Originally Posted by 95BLKMAX
Harold! w00h00!!!!!!!!!!!!!!

The drop in power after 6k is normal, I have it too. Its a cam-timing issue. Power up there isnt "all that" on the 5.5gens+, and its even more noticeable when using a 3.5 with 3.0 ECU and timing equipment. So no, I doubt your tires were spinning on the drum if they strapped down the car properly.

Yes SSIMs dont really kick-in until 4k.... and you sure as he!! know when it kicks in LOL... especially with BOOST! *hint hint Harold *
Thanks - it's good to know that - it just seemed quite abrupt. Plus their dyno charts didn't match what I know is an accurate fuel-cut RPM.

Boost, huh? Funny - yesterday I met the guy Chuong, who runs Revline, who makes very fast 9 sec. turboed Hondas for the street (and ran into another guy there with a supercharged Honda NSX I beat before). He was impressed with the old max, and offered to help me build it up some more... It's obvious that a good engine management computer would make some more HP. They had at least 6 engine builds going on there Saturday. I think that I'll look into what they can do for me...


Their web site: http://www.revlinemotorsports.com/index.php


Last edited by grey99max; 04-27-2008 at 01:04 PM.
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Old 04-27-2008, 09:42 PM
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Originally Posted by grey99max
Thanks - it's good to know that - it just seemed quite abrupt. Plus their dyno charts didn't match what I know is an accurate fuel-cut RPM.

Boost, huh? Funny - yesterday I met the guy Chuong, who runs Revline, who makes very fast 9 sec. turboed Hondas for the street (and ran into another guy there with a supercharged Honda NSX I beat before). He was impressed with the old max, and offered to help me build it up some more... It's obvious that a good engine management computer would make some more HP. They had at least 6 engine builds going on there Saturday. I think that I'll look into what they can do for me...


Their web site: http://www.revlinemotorsports.com/index.php

If they charge you more than $550 for an "engine management system".... turn it down, lol. For that much you get an Emanage Ultimate and do all you need to do with that. Not only that, but for YOUR particular realm, you dont need any timing ADVANCE, if anything you'd need RETARD. So really, EManage Blue would be just fine, which can be had for $150 shipped or less used.
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Old 04-28-2008, 08:57 AM
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Originally Posted by 95BLKMAX
If they charge you more than $550 for an "engine management system".... turn it down, lol. For that much you get an Emanage Ultimate and do all you need to do with that. Not only that, but for YOUR particular realm, you dont need any timing ADVANCE, if anything you'd need RETARD. So really, EManage Blue would be just fine, which can be had for $150 shipped or less used.
Nice play on words there...

I guess I need someone to convince me that I need an Emanage of some type. I think the timing from the stock ECU is fine - 17* advance at WOT is about right. I do have a couple of datalogging programs that show me what just happened. If A/F will be tweaked by the nitrous jets and regulated fuel pressure (42 psi now) then what can I do with an Emanage? I admit I don't get it.

When are you and streetz going to settle who is the baddest RMT Maxima in Florida? And are you selling tickets? Or videos?

.
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Old 04-28-2008, 10:18 AM
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Nice runs.

In for the 1/4 mile times.
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Old 04-28-2008, 10:56 AM
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Originally Posted by ajcool2
Nice runs.

In for the 1/4 mile times.
Maybe this Wednesday at KCIR - or Heartland if the weather holds. Maybe - more rains are coming...


I have no idea what the car will do NA..... maybe 14 flat?
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Old 04-28-2008, 09:29 PM
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Originally Posted by grey99max
Nice play on words there...

I guess I need someone to convince me that I need an Emanage of some type. I think the timing from the stock ECU is fine - 17* advance at WOT is about right. I do have a couple of datalogging programs that show me what just happened. If A/F will be tweaked by the nitrous jets and regulated fuel pressure (42 psi now) then what can I do with an Emanage? I admit I don't get it.

When are you and streetz going to settle who is the baddest RMT Maxima in Florida? And are you selling tickets? Or videos?

.
Well now we have a 3rd contender for the title. The white Maxima on my sig is officially RMT'd as of last week. Basically, we have 3 turbo maximas shooting to break into 12s. That wont be for another few months at least. I gotta pay tuition for summer and.... it aint cheap :-(.

All piggybacks are simply a way to bring out more of that potential power in your setup by doing a fine-tuning. Weather or not its worth it to you, is really up to you. All motor on the 3.0L I gained 7whp/6wtq. Gains would of course differ from setup to setup, no way to guarantee a certain amount of power from tuning due to that.
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Old 04-29-2008, 06:25 AM
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Originally Posted by 95BLKMAX

All piggybacks are simply a way to bring out more of that potential power in your setup
As raw and dated as the SAFC is, it has helped quite a bit, especially re: larger MAF housings, for me anyhow.
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Old 04-29-2008, 07:11 AM
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Originally Posted by NmexMAX
As raw and dated as the SAFC is, it has helped quite a bit, especially re: larger MAF housings, for me anyhow.
I've seen you talking about using larger MAFs - you need something to compensate for this, right? I'm running really rich at WOT, so maybe a larger MAF would lean out the engine a bit ??
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Old 04-29-2008, 08:10 AM
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Originally Posted by grey99max
I've seen you talking about using larger MAFs - you need something to compensate for this, right? I'm running really rich at WOT, so maybe a larger MAF would lean out the engine a bit ??
It helped him. As long as you can monitor AFR, trial & error would be fine.

http://forums.maxima.org/showthread....373&highlight=


That is w/no AFC.

Keep in mind, SAFC's are cheap and very easy to isntall.
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Old 04-29-2008, 08:17 AM
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Originally Posted by NmexMAX
It helped him. As long as you can monitor AFR, trial & error would be fine.

http://forums.maxima.org/showthread....373&highlight=


That is w/no AFC.

Keep in mind, SAFC's are cheap and very easy to isntall.
Yes, I've got a PLX R-300 installed now. So I need to look into a SAFC as my first step into real tuning ?? I'm so used to slamming more nitrous that I've never thought about AFC tuning..

Thanks for the feedback. 'ppreciate it..
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Old 04-29-2008, 09:51 AM
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Originally Posted by grey99max
Yes, I've got a PLX R-300 installed now. So I need to look into a SAFC as my first step into real tuning ?? I'm so used to slamming more nitrous that I've never thought about AFC tuning..

Thanks for the feedback. 'ppreciate it..
IMO, it's still a very raw way to do things. But like I said, it makes larger MAF housings much easier. Considering the success you've had in the past w/o one, it may or may not help. Considering what is on the market these days, it does pale in comparison (SAFC).

I too have an R300, I have tapped the important wires from ht ECU and have extended each wire (MAF/ECT/TPS/RPM/MPH) with a single elad wire so it makes a SAFC/PLXR300 install / reinstall VERY easy.
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Old 04-29-2008, 09:59 AM
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If you are so rich at wot while NA, try lowering your wot FP by one psi and see how much it leans out. But it is obvious that you need some sort of device to control your fuel because you are too rich in midrange and almost good towards top end.

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Old 04-29-2008, 11:32 AM
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Originally Posted by SonicDust187
If you are so rich at wot while NA, try lowering your wot FP by one psi and see how much it leans out. But it is obvious that you need some sort of device to control your fuel because you are too rich in midrange and almost good towards top end.
Actually I've already tried that - I originally had the fuel pressure at 44 psi and ran w/PLX to get numbers, then dropped the pressure to 42 psi and checked again - no changes in A/F in 2nd or 3rd gears. I've read of the same thing happening to others here in the ORG - don't know why this is true. ???

I'm telling myself I can use nitrous jetting to clean this up - tweaking jet sizes is something I've had a lot of practice doing - and yes, the car was faster with about 12:1 A/F as measured on a DD dyno. By going from 10:1 to 12:1 I picked up 2 mph in the quarter mile. But this won't level out the A/F curve, will it?
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Old 04-29-2008, 11:56 AM
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You really should use something to control your fuel. I would probably pick up Emanage blue because they are so cheap and since you spray you do not need to advance timing, which the blue cant do. But it can retard it.
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Old 04-29-2008, 12:24 PM
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Originally Posted by SonicDust187
which the blue cant do. But it can retard it.
It has been proven to advance it. Although off topic, I have to step in and state otherwise.
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Old 04-29-2008, 01:50 PM
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Originally Posted by NmexMAX
It has been proven to advance it. Although off topic, I have to step in and state otherwise.
Really, can you link me to it.
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Old 04-29-2008, 01:58 PM
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Here's the exact post, but the entire thread is great. http://forums.maxima.org/showpost.ph...2&postcount=48
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Old 05-04-2008, 07:05 PM
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MAF-time

I've been looking into MAF mods, and decided to build a 3" MAF.

Here are some pix of a stock MAF, then I hacked out the stock sensor and connector, cut off the front flange and mounted a chunk of 3" PVC (76mm I.D.) and attached that piece to the bored-out front flange. Then I cut open the PVC and made an opening for the sensor/connector block.





http://i48.photobucket.com/albums/f2...F/DSCN0245.jpg

http://i48.photobucket.com/albums/f2...F/DSCN0246.jpg



When installed this should make me into a:



I can see that the difference between the stock MAF cross-section area and the modified 76mm MAF area is considerable. I shoiuld be able to bolt this onto my new filter box when it arrives soon - the stock mounting ring is only 62mm, so a major mod is also needed here. I'll open it up to 76mm also. Hacking on plastic got easier, I found out, when I went to Home Depot and found the new plastic-cutting wheels and locking adapter for the Dremel tool. Those wheels work good!




Side issue - Squirrel whacker - 53 tails so far:

http://i48.photobucket.com/albums/f2...F/DSCN0252.jpg


Experimenting with the MAF may have rewards - if doing this raises my A/F ratio back up to 12:1 or so, then it was. Then I can explore a larger intake tract and special N2O stuff:

Dual bottles:

The dual-mount brackets:
http://i48.photobucket.com/albums/f2...F/DSCN0233.jpg




.

Last edited by grey99max; 05-04-2008 at 07:30 PM.
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Old 05-04-2008, 09:13 PM
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GO 3" MAF!!!! good job!
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Old 05-05-2008, 07:51 AM
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Originally Posted by NmexMAX
It has been proven to advance it. Although off topic, I have to step in and state otherwise.
Only with the A33B ECU, TMK. A couple people have tried it with the A32 ECU and the engine just sputters and wants to shut off.
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Old 05-07-2008, 08:16 PM
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New airbox today

Originally Posted by 95BLKMAX
GO 3" MAF!!!! good job!
I just got a new Ebay stock airbox today, opened up the hole from the box into the 76mm MAF to match the MAF, installed both into the car, and started it up. Kinda.

It was very lean and didn't want to idle, and showed 19.9 A/F at idle instead of bouncing around 14.5, so of course I went for a drive.. The engine smoothed out about 3000, but power was still way down and A/F never dropped below 14.5 even at WOT at 5000 - before, it would drop to low 11s at WOT really pig-rich at 10.8 in third gear..

Obviously it's now too lean, so I took out the airbox/MAF, re-installed the original, and put the modded MAF on the bench and added some extra material in the airflow, so I can try it again tomorrow. Maybe the A/F under WOT will show a lower number. Tomorrow.


Last edited by grey99max; 05-08-2008 at 07:25 AM.
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Old 05-07-2008, 09:05 PM
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Originally Posted by nismology
Only with the A33B ECU, TMK. A couple people have tried it with the A32 ECU and the engine just sputters and wants to shut off.
Which is puzzling... but yes as far as I know it's not confirmed on an A32


Grey, nice to see a dyno from you, although I must admit I was expecting a little bit higher number, in the 230's perhaps?
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Old 05-08-2008, 07:31 AM
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Originally Posted by DandyMax
Which is puzzling... but yes as far as I know it's not confirmed on an A32


Grey, nice to see a dyno from you, although I must admit I was expecting a little bit higher number, in the 230's perhaps?
Completely untuned and pig-rich - what can I say? That's why I'm playing with a larger MAF and airbox right now. I want to open up the air path into the TB as much as possible, and maybe raise the A/F a point or two. Yeah, I'm just playing around here, but the dual-tank dual stage nitrous system is due for installation soon. That should work better.

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Old 05-08-2008, 10:06 AM
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any plans for a safc or engine manage in the future or will you tune best you can by playing with maf then fine tune with the nitrous jets
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Old 05-08-2008, 11:32 AM
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Originally Posted by grey99max
Completely untuned and pig-rich - what can I say? That's why I'm playing with a larger MAF and airbox right now. I want to open up the air path into the TB as much as possible, and maybe raise the A/F a point or two.
Yeah I guess that would explain it...
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Old 05-08-2008, 12:38 PM
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Originally Posted by t6378tp
any plans for a safc or engine manage in the future or will you tune best you can by playing with maf then fine tune with the nitrous jets

I just don't know at the moment - I need/want to:

1. Open the intake tract and MAF as much as practical.
2. Get the WOT A/F back under control.
3. Not use any piggyback that advances ignition timing.
4. Spray a load through the motor.

Just playing with the modified MAF will be educational - I'm going to enlarge the sensor cross-section area tonight and see what happens to the A/F. I should be able to bring it back down - hopefully to 12:1. Then I can datalog that with my PLX R-300 and see how the curve looks.

If I consider any piggyback, it might be the Emanage-blue to control fuel, since I don't need most of the NA features. Guess it depends on how the next few days work out. I'll be re-installing both nitrous stages soon, and with the PLX I can easily tune the nitrous/air/fuel ratio accurately.

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Old 05-08-2008, 02:15 PM
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Originally Posted by grey99max
4. Spray a load through the motor.
LOL
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Old 05-08-2008, 02:46 PM
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What if ??

I've been struggling with the relationship between the MAF and the A/F I see on my 3.5. Then something occurred to me, based on recent experiences.

A stock MAF makes me run very rich at WOT. The MAF is stock diameter, but the midpipe is 70mm, the TB is 70mm, and the intake is much bigger than stock 3.0 parts. When the throttle is opened, the MAF sensor sees much higher airflow than normal with a 3.0, so it compensates with more fuel.

With a 3" MAF using a shortened MAF sensor, the cross-section area of the MAF is much larger than 3.0 standard, so the airflow through the sensor is much lower for a given RPM, and the car runs very lean, even at WOT.

Obviously, the injectors are controlled by only the MAF air flow, as proved by the extremes between the stock MAF and 3" MAF at WOT.

What would happen if:

1. you cut off the bottom section of the stock MAF sensor post? more area through the stock MAF..
2. you opened up a hole or two in the midpipe after the stock MAF? more air bypassing the sensor - and a larger net intake area..

I wonder if all the work of a 3" MAF is wasted if you can just bypass intake air around the stock MAF and into the midpipe, and get the same effects of a 3" MAF... holes with filters come to mind..

I have two N2O nozzle adapters in my midpipe right before the TB - if I uncovered them and covered with a light foam filter, would there be a WOT difference?

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Old 05-11-2008, 06:28 PM
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So I modified the 3" MAF by extending the bottom of the sensor stalk to the bottom on the tube. I installed it today and went for a drive. The car did indeed idle better and seemed to pull better = richer than before.

When I went WOT in 2nd gear, the A/F was about 14:1 - this is far lower than the earlier runs with this MAF using the shorter sensor stalk. The car pulled better. Remember, with the stock MAF, WOT in 2nd gear above 5K showed a 10/.8:1 A/F - way too rich. I'm looking for a balance of A/F for normal driving and achieving a 12:1 A/F at WOT. This experiment showed that the airflow through the dual-wire sensor does indeed control fuel delivery, and that the sensor flow in a 3" MAF can be adjusted by a baffle in the MAF.



The 3" MAF from the outside:


The first (very lean) 3" MAF:


The newest MAF mods, with extended sensor stalk (yet to be tested):


I installed the dual-bottle rack for the next round of nitrous for the 3.5.


This should be fun.

.
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Old 05-11-2008, 08:12 PM
  #38  
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Originally Posted by grey99max
The newest MAF mods, with extended sensor stalk (yet to be tested):


.
Is it me or that piece that you added to the bottom would really mess up the airflow to the engine?
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Old 05-12-2008, 06:57 AM
  #39  
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Originally Posted by SonicDust187
Is it me or that piece that you added to the bottom would really mess up the airflow to the engine?
It's you. The point of temporary pieces is to change the airflow into the round opening where the dual-wire sensor lives. A smaller piece lowered the WOT A/F from 19:1 to 14.1 - so I'm trying a larger piece to find a WOT compromise at 12:1 A/F. The black RTV strips out easily and is hard to overlook.

The problem with a 3" MAF opening and a stock 4th gen air sensor is that the sensor does not read correctly, but it gives a very lean WOT A/F because of the lower velocity through the sensor. The stock MAF is at the other extreme with a 3.5 - the airflow through the sensor is much higher than stock, which richens the A/F to crazy levels (10.8).

I may also add a larger cone right on the sensor, to pick up more air through the dual-wire sensor, along with some mini egg-crate to straighten up air flow. If this works, this may be the best solution.

I need to settle this one before tuning with nitrous. The heated dual bottles and my Alaskan Pipeline -6AN feed line can handle whatever I need at the nozzles - but I need to settle the MAF issue first, for normal driveability.

.
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Old 05-13-2008, 06:35 AM
  #40  
dot dot dot ...
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Ever think of maybe getting a SAFCII, cheap / easy / more convenient way of getting the desired AFR?

SAFC = very raw
What you're doing = prehistoric
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