3.5 swap How can I eliminate the mid range dead spot?
12-08-2007, 10:46 AM
#6
My point is that it's a VE issue. Anything short of a different IM design or VTC's won't help that. I was saying it in case he had a modified IM or was running it with the power valve open full time.
12-08-2007, 04:51 PM
#14
The general shape did change a bit but it is still recognizable. The hole in the powerband that is created by a inoperative 2k2 VI can not be erased with timing since the engine takes a major hit in VE. This is exacerbated by the fact that a stock 3.0 ECU's timing dips around the same RPM range. My point is that change in VE > change in timing with respects to an engine's power delivery. You can increase torque with timing, but that dip will be there relative to the rest of the powerband regardless.
12-08-2007, 05:12 PM
#15
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I dunno, I have a working VI and gave a big 
to everyones description in that other thread, and boy does the dip in power sure go along with the dip in timing shown on the graphs in that other thread.
Until someone advances the hell out of the timing in that flat range on a 4.5gen w/3.0 ecu
to everyones description in that other thread, and boy does the dip in power sure go along with the dip in timing shown on the graphs in that other thread. Until someone advances the hell out of the timing in that flat range on a 4.5gen w/3.0 ecu
12-08-2007, 09:19 PM
#16
or just have a device that will throw a few PSI from just before that RPM range.. should help the VE issue 
.
But yea, needs timing advance (to at least 5.5gen levels), a working VI, and VCTCs.
.But yea, needs timing advance (to at least 5.5gen levels), a working VI, and VCTCs.
12-09-2007, 01:50 PM
#21
12-09-2007, 01:51 PM
#22
its in the 98....
wait, I know my friend's friend has an original 3.5 sitting in his garage....ohhhh, what else would i need, ecu and lots of patiance with rewiring?
wait, I know my friend's friend has an original 3.5 sitting in his garage....ohhhh, what else would i need, ecu and lots of patiance with rewiring?
Last edited by goldtooth; 12-09-2007 at 01:53 PM.
12-09-2007, 05:01 PM
#23
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3.5 swap
I need help, it wont let me post a new thread and im getting ready to start my swap. I just was wondering how everyone went about with the variable intake on the 03. Im using the ecu from my 97 and was just going to wire an rpm switch into it. Any other thoughts other than what is already in the stickys?
12-09-2007, 06:08 PM
#24
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Like most people, I use a window switch so that I can have it function as normal (1800-3600) But I see no problems with using an rpm switch and just have it closed from 0-3600. I think there is speculation the only reason it is open from the factory from 0-1800 is to reduce the crazy low-end grunt of the 3.5, but I don't know. Setting it either way from 0-1800 made no difference for me 
Last edited by KRRZ350; 12-09-2007 at 06:12 PM.
12-09-2007, 09:08 PM
#26
12-10-2007, 08:38 AM
#29
12-10-2007, 08:47 AM
#30
LOL. goldtooth as much as I agree is the PW'ing going on, unfortunately there's nothing else that could be said for the original subject that hasnt been mentioned already.
However one thing I can add to it...
I too have that dead spot. I of course have 3.0 ECU, and a "treated IM". Timing advance will help, but only up to a point. In relation to the rest of the curve, yea you'll still have a dip in that region.
HOWEVER... If you get an EU and extend that redline to ~7100-7200, everytime you shift its going to land you just past the dead spot. Therefore, you'd only experience it in 1st gear. This is with racing though, street driving is another story.
Around the street, really the only thing you could do is have a functioning VI and be able to advance the timing to at least 5.5 gen midrange levels.
However one thing I can add to it...
I too have that dead spot. I of course have 3.0 ECU, and a "treated IM". Timing advance will help, but only up to a point. In relation to the rest of the curve, yea you'll still have a dip in that region.
HOWEVER... If you get an EU and extend that redline to ~7100-7200, everytime you shift its going to land you just past the dead spot. Therefore, you'd only experience it in 1st gear. This is with racing though, street driving is another story.
Around the street, really the only thing you could do is have a functioning VI and be able to advance the timing to at least 5.5 gen midrange levels.
12-13-2007, 04:18 PM
#31
I have the same dead spot w/o a ssim mod, running the 3.0 ecu of course. By advancing timing you do mean w/ the consult II to about 17 degrees? Correct me if I am wrong 95blkmax, thanx in advance
12-13-2007, 04:29 PM
#33
12-13-2007, 04:36 PM
#34
12-13-2007, 05:49 PM
#36
It has actually been a couple of years, I’m pretty sure you just missed the thread. I think it's valid for this particular thread too, useful.
http://forums.maxima.org/oldthread.php?t=434821
http://forums.maxima.org/oldthread.php?t=434821
12-13-2007, 07:20 PM
#37
Also, I get HORRENDOUS gas mileage. I lowered the fuel pressure down the 28 psi at idle.
I tried to tune it, but any adjustments I make on the SAFC2, there is no results on the A/F ratio graph a la laptop..... Im pretty sure the connections are all good, I'm getting readings from the sensors....any ideas?
I tried to tune it, but any adjustments I make on the SAFC2, there is no results on the A/F ratio graph a la laptop..... Im pretty sure the connections are all good, I'm getting readings from the sensors....any ideas?
12-13-2007, 07:29 PM
#39