Think you future 3.5 swappers might want to consider this
#41
Supporting Maxima.org Member
Thread Starter
iTrader: (8)
Join Date: Apr 2003
Location: Miami, FL
Posts: 9,116
Originally Posted by 95naSTA
Very interesting thread..
Just out of curiosity, how much is cam timing adjusted by adv/retarding one cam sprocket tooth?
Just out of curiosity, how much is cam timing adjusted by adv/retarding one cam sprocket tooth?
#42
Originally Posted by nismology
With that said, it's not a good idea to change the cam timing like this. All the sprockets need to be in perfect synchonization for the ECU to be able to do it's job properly.
I'm just thinking in the case of the exhaust cam, instead of having to redrill another hole you could adjust it 17.1 or 34.3 crank degrees.
#43
Supporting Maxima.org Member
Thread Starter
iTrader: (8)
Join Date: Apr 2003
Location: Miami, FL
Posts: 9,116
Originally Posted by 95naSTA
Why would it make the ecu unhappy?
I'm just thinking in the case of the exhaust cam, instead of having to redrill another hole you could adjust it 17.1 or 34.3 crank degrees.
BTW, the 8.57* assumed you were talking about the intake cams. The exhaust cam timing would change a lot more since the exhaust sprockets have substantially fewer teeth.
#44
Supporting Maxima.org Member
iTrader: (29)
Join Date: Oct 2005
Location: Middleboro/Carver, Ma
Posts: 4,572
so I'm lost then, I thought the 3.5 VI also tuned the intake runners length to take advantage of the resonance supercharging effect, so it is just a variable port design that opens additional high-end ports? how can that be since it's not on the lower manifold or head? if it is lengthened runners like the de-k than I don't see how the intake cam timing effects the rpm of that effect since it delays the opening of the intake valve AND the closing so the pulse wave would still start and return to the valve at the same time for a given rpm, sorry if I confused the hell out of you nismology like I just did to myself, I just need help to understand the 3.5 VI and cam timing a little better
maybe stephen max and the other person who is getting adaptors made within the next few days could hop in here......maybe if that other person is running a similiar set-up I'd be willing to take my car to the dyno [even though it wouldn't be too accurate of a comparison] w/49* assuming it wouldn't be to much hassle for stephen max to set me up with that, I am leary though since it will retard the exhaust timing and I'm not clear on how/why that will effect the powerband (sorry to be asking for so much knowledge) and I def. can't afford to burn a valve either
maybe stephen max and the other person who is getting adaptors made within the next few days could hop in here......maybe if that other person is running a similiar set-up I'd be willing to take my car to the dyno [even though it wouldn't be too accurate of a comparison] w/49* assuming it wouldn't be to much hassle for stephen max to set me up with that, I am leary though since it will retard the exhaust timing and I'm not clear on how/why that will effect the powerband (sorry to be asking for so much knowledge) and I def. can't afford to burn a valve either
#46
Supporting Maxima.org Member
Thread Starter
iTrader: (8)
Join Date: Apr 2003
Location: Miami, FL
Posts: 9,116
Originally Posted by KRRZ350
so I'm lost then, I thought the 3.5 VI also tuned the intake runners length to take advantage of the resonance supercharging effect, so it is just a variable port design that opens additional high-end ports?
maybe stephen max and the other person who is getting adaptors made within the next few days could hop in here......maybe if that other person is running a similiar set-up I'd be willing to take my car to the dyno [even though it wouldn't be too accurate of a comparison] w/49* assuming it wouldn't be to much hassle for stephen max to set me up with that, I am leary though since it will retard the exhaust timing and I'm not clear on how/why that will effect the powerband (sorry to be asking for so much knowledge) and I def. can't afford to burn a valve either
#47
Supporting Maxima.org Member
iTrader: (29)
Join Date: Oct 2005
Location: Middleboro/Carver, Ma
Posts: 4,572
well in my case where I will be using adaptors I geuss I am stuck at 44* on the int. I'm still confused on the 3.5im though, I understand the principles of internal resonance supercharging I've been assuming your talking about that the whole time, maybe I'm on a different page though, when you say dynamic supercharging you do mean when the inertia from the incoming air hit's the back of the intake valve as it closes and then bounces back as the intake valve is opening again which happens at a certain rpm based on runner length?
#48
Supporting Maxima.org Member
Thread Starter
iTrader: (8)
Join Date: Apr 2003
Location: Miami, FL
Posts: 9,116
Originally Posted by KRRZ350
well in my case where I will be using adaptors I geuss I am stuck at 44* on the int.
I'm still confused on the 3.5im though, I understand the principles of internal resonance supercharging I've been assuming your talking about that the whole time, maybe I'm on a different page though, when you say dynamic supercharging you do mean when the inertia from the incoming air hit's the back of the intake valve as it closes and then bounces back as the intake valve is opening again which happens at a certain rpm based on runner length?
#49
Supporting Maxima.org Member
Thread Starter
iTrader: (8)
Join Date: Apr 2003
Location: Miami, FL
Posts: 9,116
Originally Posted by Broaner
Very interesting info and I'm following and learning and listening as best I can. I still have this question though. "The standard way to do the cam swap involes drilling the new holes XXX degrees in the counterclockwise direction." I've never seen where anyone says what full VTC retard is in cam degrees from the OEM 30 dowel. Please someone point me.
#50
Supporting Maxima.org Member
iTrader: (29)
Join Date: Oct 2005
Location: Middleboro/Carver, Ma
Posts: 4,572
Originally Posted by nismology
Couldn't you just order the adapters with custom specs? Or have you already received them?
so out of curiosity/desire to learn, I have to ask yet one more question on the 3.5im, (you can pm the answer if you don't want to clutter this thread with stuff other than cam info)- what are the principles that the 3.5 variable effective runner length works on versus the traditional dynamic supercharging
#51
Supporting Maxima.org Member
iTrader: (17)
Join Date: Aug 2004
Location: Montreal, Qc, Canada
Posts: 5,437
With what SR20DEN posted in the VQ35HR thread it looks like my 70* intake valve closing guess was pretty good; my nismo cams have the same 10.5 mm lift as the VQ35HR and VQ35 Rev-up 7100 rpm motor, just more duration (262* instead of 248*):
Originally Posted by SR20DEN
2007 VQ35HR
The VQ35HR has slightly different cam timings than the VQ35DE 'Revup'.
VQ35DE 'Revup' cam data
Engine: VQ35DE (3)
Model Years: 2005-2006 (G35mt, 35th Anniversary 350Z)
CVTC: Intake and Exhaust
Intake__Lift: 10.5mm
Exhaust_Lift: 10.5mm
Intake__Duration: 248º
Exhaust_Duration: 248º
Intake_Opens: 2º ATDC
Intake_Closes: 70º ABDC
Exhaust_Opens: 70º BBDC
Exhaust_Closes: 2º BTDC
Overlap: -4º
----------------
VQ35HR
Engine: VQ35DE
CVTC: Intake and Exhaust
Intake__Lift: 10.5mm
Exhaust_Lift: 10.5mm
Intake__Duration: 248º
Exhaust_Duration: 248º
Intake_Opens: 2º BTDC
Intake_Closes: 66º ABDC
Exhaust_Opens: 68º BBDC
Exhaust_Closes: 0º BTDC
Overlap: 2º
The intake cam has been advanced by 4º and the exhaust cam has been advanced by 2º.
The VQ35HR has slightly different cam timings than the VQ35DE 'Revup'.
VQ35DE 'Revup' cam data
Engine: VQ35DE (3)
Model Years: 2005-2006 (G35mt, 35th Anniversary 350Z)
CVTC: Intake and Exhaust
Intake__Lift: 10.5mm
Exhaust_Lift: 10.5mm
Intake__Duration: 248º
Exhaust_Duration: 248º
Intake_Opens: 2º ATDC
Intake_Closes: 70º ABDC
Exhaust_Opens: 70º BBDC
Exhaust_Closes: 2º BTDC
Overlap: -4º
----------------
VQ35HR
Engine: VQ35DE
CVTC: Intake and Exhaust
Intake__Lift: 10.5mm
Exhaust_Lift: 10.5mm
Intake__Duration: 248º
Exhaust_Duration: 248º
Intake_Opens: 2º BTDC
Intake_Closes: 66º ABDC
Exhaust_Opens: 68º BBDC
Exhaust_Closes: 0º BTDC
Overlap: 2º
The intake cam has been advanced by 4º and the exhaust cam has been advanced by 2º.
#55
Supporting Maxima.org Member
iTrader: (1)
Join Date: Mar 2003
Location: Beaverton, Oregon
Posts: 735
Originally Posted by Nismo87SE
I was wondering if anyone has actually measured the change in power vs change in cam timing? The consensus is that retarding the intake cam is the way to go, however during actual tuning it might not. Now I've done a lot of tuning in my own car with adjustable cam gears. Unless I'm totally mistaken, basically what I found is that advancing intake cam relative to stock increases torque in low-midrange while making the idle rougher. Now retarding the intake cam reduces low-midrange torque but it does make a little more power up top and the idle is smoother.
For the exhaust cam in my case doesn't seem to make much of a difference in power given retard or advance. However, it will make the idle smoother by retarding the exhaust. Right now I'd pay good money if my engine (SR20DE) was able to be retrofitted with VTC control. If I could get like 9* of change, I could gain like 8-11wtq below 6000rpm and gain like 10-12whp over 6000rpm if able to retard intake cam as well. With aftermarket cams someone needs to do different intake/exhaust cam positions to find best overall torque curve.
For the exhaust cam in my case doesn't seem to make much of a difference in power given retard or advance. However, it will make the idle smoother by retarding the exhaust. Right now I'd pay good money if my engine (SR20DE) was able to be retrofitted with VTC control. If I could get like 9* of change, I could gain like 8-11wtq below 6000rpm and gain like 10-12whp over 6000rpm if able to retard intake cam as well. With aftermarket cams someone needs to do different intake/exhaust cam positions to find best overall torque curve.
Your platform is desireable in this case, as you have the option of a SR20VE and all the goodies that come with it.
#58
Thanks everyone for the thoroughness of this thread and good info to help out all us future 4.5 gens.
Can we sum it up for clarification? i.e. which method produces which timing. (we've already concluded that the 53 ABDC intake closing, produced by tilley's drilled cams, is "good"). That leaves stephen max's adapters (and that's all i know of as far as people who offer adapters or drilling service).
Was the 44 ABDC conclusion wrong (for the adapters)? I think that is what you're saying in the addendum to the 1st post but not sure.
Can we sum it up for clarification? i.e. which method produces which timing. (we've already concluded that the 53 ABDC intake closing, produced by tilley's drilled cams, is "good"). That leaves stephen max's adapters (and that's all i know of as far as people who offer adapters or drilling service).
Was the 44 ABDC conclusion wrong (for the adapters)? I think that is what you're saying in the addendum to the 1st post but not sure.
#59
Originally Posted by TomV
Thanks everyone for the thoroughness of this thread and good info to help out all us future 4.5 gens.
Can we sum it up for clarification? i.e. which method produces which timing. (we've already concluded that the 53 ABDC intake closing, produced by tilley's drilled cams, is "good"). That leaves stephen max's adapters (and that's all i know of as far as people who offer adapters or drilling service).
Was the 44 ABDC conclusion wrong (for the adapters)? I think that is what you're saying in the addendum to the 1st post but not sure.
Can we sum it up for clarification? i.e. which method produces which timing. (we've already concluded that the 53 ABDC intake closing, produced by tilley's drilled cams, is "good"). That leaves stephen max's adapters (and that's all i know of as far as people who offer adapters or drilling service).
Was the 44 ABDC conclusion wrong (for the adapters)? I think that is what you're saying in the addendum to the 1st post but not sure.
Bump for the addendum.
#60
Supporting Maxima.org Member
Thread Starter
iTrader: (8)
Join Date: Apr 2003
Location: Miami, FL
Posts: 9,116
Tilley times the intake cams so the lobe seperation angle is the same as the 3.0 cams. This results in an intake valve closing @ 53° ABDC and 13° of overlap.
Stephen Max times them so that the intake valve closing event happens at the same time as the 3.0 cams. This results in an intake valve closing @ 49° ABDC and 17° of overlap.
Stephen Max times them so that the intake valve closing event happens at the same time as the 3.0 cams. This results in an intake valve closing @ 49° ABDC and 17° of overlap.
#61
Supporting Maxima.org Member
iTrader: (29)
Join Date: Oct 2005
Location: Middleboro/Carver, Ma
Posts: 4,572
I had stephenmax custom make my adaptors to 56* intake closing, it cost me a little more I believe ($125). All I have to go by is comparing it to a 4at 3.5, but damn this thing really pulls up top.
#62
Originally Posted by nismology
Tilley times the intake cams so the lobe seperation angle is the same as the 3.0 cams. This results in an intake valve closing @ 53° ABDC and 13° of overlap.
How dramatic do you think the difference is from 64* on the DE? and why do you think he did 53* instead of 64*
Originally Posted by nismology
Stephen Max times them so that the intake valve closing event happens at the same time as the 3.0 cams. This results in an intake valve closing @ 49° ABDC and 17° of overlap.
I'm going to go tune very soon and I want to be able to explain the differences between the stock vq35de and the way Tilley set my car up. Also the fact that the timing on the 3.0 ecu is different than the 3.5ecu.
I'm not familiar with the exact specs on the 3.0 cam timing or the 3.5 with Tilley's setup.
What are the most significant things to mention to the tuner so he can maximize the session?
Could someone do a comparison so the numbers are all lined up; like the HR cam data a few posts back. That would really consolidate the information between the swaps and the stock 3.5 motors.
#65
Supporting Maxima.org Member
Thread Starter
iTrader: (8)
Join Date: Apr 2003
Location: Miami, FL
Posts: 9,116
Originally Posted by oTranscendental
ok... all i really want to know is what the effect of not having 64* is on my power band, and where I'm losing most power.
#66
Originally Posted by nismology
You're missing out on some low-end and top-end power. The VQ35 ECU retards the intake cams at low RPM to minimize overlap, advances it in the mid-range to improve dynamic compression by causing the intake valve to close earlier, then retards it up top to promote more complete cylinder filling.
Aside from adjustable cam gears, or working vtc, what can I do to get some of that power back?
I still have the 3.0 TB/ and MAF. I heard of someone using a Ford 3" MAF. If I replace these, I'm sure I'll get some more power but will it mess with my idle and smooth operation?
Sorry for all the newb questions, I'm just trying to maximize the setup before I go tune. For example I heard of some guy bolting the MAF directly to the IM by deleting the midpipe. Short of trying all the little mods myself does anyone know of a a setup that will keep good streetability and still wail in the High rpms? I'm contemplating the gutted IM, but we all know that kills your low-end
Thread
Thread Starter
Forum
Replies
Last Post
MaxRPM6
New Member Introductions
0
09-11-2015 06:56 PM