Tuning, A/F Ratios, Etc What's the deal??
#1
Tuning, A/F Ratios, Etc What's the deal??
After someone gets a full VQ35 swap (I'm talking block, heads, IM whether its 2k2 IM or '00 VI) and maintains stock VQ30 ECU, with VQ30 Timing equipment what if any tuning is required? How would the AFR's be? Tilley recommended keeping the stock vq30 ECU stock, simply because it has the optimal settings for the VQ35. So far from what I understand a VQ30 ECU on a full VQ35 swap (minus VTC, wiring, and ECU) simply detects more air because of larger displacement. However, I see many individuals here who have swapped motors or have had others swap mention that they need to tune and what not.
So what exactly needs to be tuned and is it required. Will one run lean or rich with '00VI or with a 2k2 IM. The only reason I would consider getting a TS or JWT ECU would be to take advantage of a higher rev. limiter. This is solely based on Tilleys recommendations. So guys what's the scoop with tuning, fill me in!
So what exactly needs to be tuned and is it required. Will one run lean or rich with '00VI or with a 2k2 IM. The only reason I would consider getting a TS or JWT ECU would be to take advantage of a higher rev. limiter. This is solely based on Tilleys recommendations. So guys what's the scoop with tuning, fill me in!
#2
No one with the swap has really dyneod. So A/F cannot be determined just yet. Tilley has, but I don't remember seeing the A/F, it exsists, but I haven't haven't looked in too great of detail for it, but you donate so search on. But I would also like to see vlasy, JClaw, maybe even dubbya dyno ... with the latter 2 running on 4th gen ECU's.
#3
Originally Posted by NmexMAX
No one with the swap has really dyneod. So A/F cannot be determined just yet. Tilley has, but I don't remember seeing the A/F, it exsists, but I haven't haven't looked in too great of detail for it, but you donate so search on. But I would also like to see vlasy, JClaw, maybe even dubbya dyno ... with the latter 2 running on 4th gen ECU's.
#6
Originally Posted by NmexMAX
Way way off.. but I wonder what he would've done SAE since it was a mild day and overall non-ideal conditions.
#9
Another thing to keep in mind is that my engine was pretty heat soaked. It took me 45 minutes or so to get to the dyno on a hot day and my car only set for like 10 minutes before the dyno. Lots of factors involved here.
#10
Originally Posted by Dubbya
Another thing to keep in mind is that my engine was pretty heat soaked. It took me 45 minutes or so to get to the dyno on a hot day and my car only set for like 10 minutes before the dyno. Lots of factors involved here.
#15
Originally Posted by JClaw
The important part of the tuning is ignition timing advance. VQ35's can run far more advance, so to get the most out of our VQ35s, we need to advance timing A LOT.
#16
Supporting Maxima.org Member
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You're paranoid
I am not ready to dyno yet. I just spent 700$ this week and I'd need an extra 500$ to get the 300zx conversion completed, we're working on the crank sensor issue.
I will get better track numbers this weekend though.
I am not ready to dyno yet. I just spent 700$ this week and I'd need an extra 500$ to get the 300zx conversion completed, we're working on the crank sensor issue.
I will get better track numbers this weekend though.
#17
No not but you always specify A LOT, but no #'s .And I'm not interested in what is going to hurt my car if that's what you're implying because I don;t have a 3.5 hybrid setup(running on 3.0 ECU), but merely, I'm interested as to how much more gains are possible with these 3.5 hybrids.
.. I can drink A LOT of whiskey, but A LOT in your and my words can differ.. Also as stated in previous posts by the well respected and reputable BlackBIRDVQ, that with too much advancement no gains but rather a loss is experienced...
I think I know where you're getting this "A LOT" more is safer with the 3.5L concept from. But for confirmation ... where?
.. I can drink A LOT of whiskey, but A LOT in your and my words can differ.. Also as stated in previous posts by the well respected and reputable BlackBIRDVQ, that with too much advancement no gains but rather a loss is experienced...
I think I know where you're getting this "A LOT" more is safer with the 3.5L concept from. But for confirmation ... where?
#18
Originally Posted by JClaw
You're paranoid
I am not ready to dyno yet. I just spent 700$ this week and I'd need an extra 500$ to get the 300zx conversion completed, we're working on the crank sensor issue.
I will get better track numbers this weekend though.
I am not ready to dyno yet. I just spent 700$ this week and I'd need an extra 500$ to get the 300zx conversion completed, we're working on the crank sensor issue.
I will get better track numbers this weekend though.
#20
Originally Posted by Kevlo911
Too much timing = knocking = timing pulled back = power loss. I expierenced this on the dyno at Maxus.
Edit: I would also like to add that if you use an octane that is to high, you will lose power. With advanced timing its critical to match your fuel octane to the amount of advance your are using.
#21
Originally Posted by 98SEBlackMax
Theres a theoretical limit to how far you can advance spark on any given engine. Even with race gas theres a finite limit, to best of my knowledge no one has mentioned where it stops gaining on a VQ30/35. However with the VQ35s they can attain more advance on lower (IE 93~95) octane because of better heads but even with race gas they are ultimately limited as well.
Edit: I would also like to add that if you use an octane that is to high, you will lose power. With advanced timing its critical to match your fuel octane to the amount of advance your are using.
Edit: I would also like to add that if you use an octane that is to high, you will lose power. With advanced timing its critical to match your fuel octane to the amount of advance your are using.
#22
Originally Posted by deezo
Well, I know 89 is bad with a TS ECU but what would be bad on the high end of the octane scale?
#23
Moderator who thinks he is better than us with his I30
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If I had a VQ35 using a VQ30 ECU I would go with something like an SMT-6 or some other piggy back or stand alone that would allow me to tune the AF and timing myself. I would not trust that a TS or JWT would be right for that type of set up.
#25
Originally Posted by SR20DEN
Come on guys. There are alot of smart people in here, can't you figure this one out?
13.5~14.0 A/F at WOT for 1/4 mile use and 12.5~13.0 A/F at WOT for road course use. With the SMT-7 I should be able to tune wideband so those values will be consistant and not be a static map.
Timing advance is variable. It depends on the engine, fuel octane, A/F ratio, and atmosphere conditions for the most part.
#27
Originally Posted by SR20DEN
The best solution for controlling a VQ35 without a VQ35 ECU.
If JWT or TS developed a good all around program for a VQ35 swap in a 4th gen that would probally be the cheapest option. But IMO this wouldnt work for everyone, one size does not fit all...
OBD-1 300ZX ECU swap if Jclaw can figure it out, but that rules out some states emissons testing because of lack of OBD-2. Pricing is to be determined...
Me im biased because of the SMT, so I would use an aftermarket ECU with just a rev limit increase and control the timing & air/fuel with the SMT-7. It's not the cheapest option but i would have control over a good part of the engine while retaining my OBD-2 emissons control systems. The main reason I bought a '96 was OBD-2 testing. All they do now in Mass is scan the computer for codes and pass you. Ive used resistors and other tricks to fool the ECU and have passed several times.
#34
Originally Posted by nismology
I'm waiting on some smart-a$$ answer like "Use the VQ35 ECU...duh!!!" or something...
Keep going. And if you had read what I actually said you woudl know I have already established that isn't the case.
#35
Originally Posted by SR20DEN
You're half right.
Keep going. And if you had read what I actually said you woudl know I have already established that isn't the case.
Keep going. And if you had read what I actually said you woudl know I have already established that isn't the case.
#36
Originally Posted by nismology
Well i know you said not the VQ35 ECU. But you also said it's not aftermarket. How can something not be either stock or aftermarket??
There is a point and a reason behind all this.
I don't want to just give the answer away. I want everyone to understand what the answer is and WHY the answer is what it is.