96sleeper

iTrader: (4)

I rarely post, but I have been seeing more and more posts about the vtc's making some astronomical difference in power. People post like there will be a full second difference in the 1/4 mile times with a full VQ35 swap instead of using VQ30 timing equipment on a VQ35. I would like people with actual concrete evidence to post, not just heresay.

I am all for area under the curve and fully agree the car with the most area under the curve will be faster, but when racing I am rarely or never below 4000 rpm, especially on slicks. For many people doing the swap this way is much simpler and easier, and it is a viable option. A car can still make good power without vtc's.

I would like to see some more information regarding this if anyone has any. I remember SR20DEN dynoing a long time ago and un-hooking the vtc's to do a comparison, but that would not translate to a 3.5 swap with VQ30 timing equip where the cams will be drilled in a location that is middle of the road, not one extreme or another.

I have viewed many runfiles including SR20DEN and 6spdhayes, and compared them to my all motor runfiles and there is very little difference in low end, and I have aftermarket cams which hurt the low end even more. Below 4000 rpm the difference varies from 1-10 lb-ft, and 1-5 hp lower than either of theirs. Hardly the huge difference everyone talks about.

Post up...I have my flame suit on.

made in china

iTrader: (7)

I have no "proof" in form of dyno results per se, but I feel very confident that the full VQ35 swap will outperform a hybrid swap. You have cams, so you basically are more modded than most maxima's here. I have seen many low (relatively speaking) HP hybrid swaps on here. Basically, a few people putting down less than 200 whp, some AT putting down 170-180 IIRC. All the other dyno's of hybrids making near stock Gen 5.5 power levels have what I consider a good deal of mods.

Anyways, Nissan wouldn't invest in VTC and VIAS if it didn't perform. I am biased since I am wrapping up a full Gen 5.5 swap. I see it this way, all the effort hybrid swappers put into swapping timing components, adding I/H/E, adding A/F modifications like VAFC etc isn't any less effort than I need to do a full Gen 5.5 swap. It's kind of a wash IMO, a mildly modded hybrid swap making similar power as a stock Gen 5.5 full swap. However, the full Gen 5.5 full swap leaves the door to mods wide open with a more complete starting point. Put all the mods a average hybrid swapper has onto a full Gen 5.5 swap and the full swap will smash on the hybrid.

Me, I like all the new, updated Gen 5.5 hardware whirring away in my car. I would be dissatisfied with myself if I did not go all out. Besides, like anything around here, those who don't have it, say they don't need it. Those who do have it say they would never do without. Oh well....

grey99max

iTrader: (12)

So are you taking this "full Gen 5.5 swap" to the strip when it's finished? Just curious.....

96sleeper

iTrader: (4)

You must not have read my post. I don't want to know what you think is better, just because you think so. I want concrete evidence. Obviously you think it makes a huge difference because you did the full swap.

Like I said, I am all for area under the curve, I just think it is a very small return for the extra work.

made in china

iTrader: (7)

Holy crap you are very defensive.

BTW, yes the full swap VQ35DE with AT is proven to lay the smackdown on hybrid AT swaps. Why? Not sure what went wrong with other people's swaps. I am thinking of "dubbya"s hybrid swap compared to "Jime"s full swap. Not even close.

Anyway, most people run MT with there VQ35 whatever swaps. You wouldn't be able to check my 1/4 mile times against many other AT's. I am not going for fastest swap, just most complete. And I'll never need to argue with anyone which way is better, because I know in my head which way I think is better. Which is not the same way as you think.

BTW, many lightly modded Gen 5.5 AT's put out over 230+ WHP. The same kinds of mods needed to make a Hybrid swap put out similar numbers with MT. What do you mean opinions? I don't have time to "Free Google" search the proof. You know what I am talking about.

96sleeper

iTrader: (4)

I am not being defensive, I just don't want this thread to fill up with people's opinions. I want people to post good solid info so others can make informed decisions.

made in china

iTrader: (7)

So then use the SEARCH button. Like I have been told anytime I ask a question, you better search 'cause it's all here somewhere.

96sleeper

iTrader: (4)

Here is a runfile comparison of three of the most modified VQ35's that I have saved on my computer. Two of them have full working 3.5's with VTC's, one has VQ30 timing equipment with aftermarket cams.

The red one is the non-vtc engine, and you can see, yes the torque and hp are a little lower below 4000rpm, but it does have aftermarket cams which hurt low end power. Seems to me that there is not a huge difference though. It would hurt an auto car more, but the majority of maxima people that like to drag race have 5 speeds.

96sleeper

iTrader: (4)

lol, do you see how long I have been on this site. I have been telling people to search long before you were ever on here. Opinion is what is always posted about this topic, I am looking for more.

grey99max

iTrader: (12)

This thread went to he11 in record time. I think that 96sleeper took a valid position in questioning VTC/nonVTC 3.5 swaps. I'm interested, because I'm well into a 3.5 build, and I'm staring at the VTCs on my 3.5 and wonder if I should try to keep them or complete the 3.0 timing conversion when my ARP rod bolts get here.

The Original Poster has set the question out for reasonable answers. If anyone has one or two, share them with us - but keep it civil here.

Kiddies don't make successful 3.5 installations of any sort.

nismology

iTrader: (8)

I don't have any concrete evidence to post at this time since I don't know of any mod-for-mod comparison yet. I'll search for some if I get a chance. I don't know of anyone that thinks that CVTC will make a full second improvement in the 1/4 (yes I know you were exaggerating) though. That's rediculous. At the same time though, I'm a firm believer that the car powered with the CVTC-equipped motor will be faster an quicker in the 1/4 mile. How much, can't say. The advantage of VTC's can manifest itself somewhat with just bolt-ons and stock CVTC maps, as your dyno comparison suggests, but it doesn't end there. The biggest advantage is when you start revising the VTC maps in conjunction with aggressive cams. For instance, no one in their right mind would think that curves between a hybrid motor with tomei 280/272 cams and a Full 3.5 with the same cams + V-manage (or TS reflashed cam timing) would be similar. I've seen a 350Z dyno comparo where a dyno curve with 295/265 cams, bolt-ons, and TS revised cam timing, head work and tuning was compared to the stock baseline. It made more power/torque from 3k on up. http://www.my350z.com/forum/showthread.php?t=166639

I know it's not exactly a head-to-head comparison but I seriously doubt that could ever happen with a CVTC-less motor with comparably aggressive cams. Either way, I don't think it's fair to call it a "small return" yet without any mod-for-mod comparisons. I'd like to see dyno comparisons of motors with operating VI's for starters since the stock A33B CVTC maps were designed around them.




P.S. I do agree that your tone seems a bit defensive. Doesn't really sound like you're COMPLETELY at peace with your setup. If i'm mistaken, pardon me.

P.S.S. I find it interesting that the green curve holds comparable (if not slightly more) power past the stock rev-limit despite the lack of aftermarket cams.

nismology

iTrader: (8)

Also, I feel that if anyone has to ask whether or not going with the full 3.5 swap is worth it, it's not for them. The people that go through with it have their reasons (CVTC is only one of them) knowing it's going to be substantially more difficult and pricey, and the people that don't have theirs (ease of installation). I doubt you'd ever hear a full swapper say "I wish I'd never done it this way" though.

96sleeper

iTrader: (4)

I assure you, I am not being defensive. I just want someone to be able to prove me wrong. I wish they did make a bigger difference, I would be all over it. And you are right, they are great for people with aftermarket cams since they keep the low end loss to a minimum. I just keep seeing post after post about what a huge difference there is, and no one can back up those claims so I wanted to see some info. I still feel good about my setup, but I don't know of anyone that mods car that is completely at peace with any setup, there is always new things to try. If I thought I could pick up 30 lb-ft across the board below 4500 rpm, I would be all over it.

All three cars in that comparison are SSIM equipped...That mods appears to hurt low end as much or more than the vtc's....

nismology

iTrader: (8)

It's possible to even gain some low-end (and everywhere else) if the CVTC map is modified appropriately depending on the cam grind. Also, your dyno comparison suggests that a CVTC-equipped motor will do better at high RPM mod-for-mod. The dyno's i've seen of sans-VTC motors say the same.

The stock FWD CVTC map is relatively mild when compared to the 350Z maps and is seemingly built around an operating VI. I'd like to see a 350Z VTC map/SSIM equipped maxima thrown into the dyno mix to see how much of a difference it would make. NmexMAX would fit the bill but he has an auto.

made in china

iTrader: (7)

It is a nearly impossible request for someone to "prove you wrong". You'd be hard pressed to find similar cars to compare. The full 3.5 is a different beast than the hybrid, and there are enough variables that you could argue just to argue for arguements sake. I think one of the other reasons Nissan deployed VTC on these motors is to improve emissions. VTC can eliminate the need for EGR, allowing the cylinder head to perform that function instead of aux equipment like an EGR valve.

scrhale

I think the use of CVTC has also been taken out of context. Although it is possible, I seriously doubt that the only time you will drive your Max is on the strip. What if you are in 3rd or 4th at 2.5-3.5K on the interstate and want to accelerate. You may not need to downshift since that extra low-end is there. There are plenty of situation when you will be in your low-end power. It makes the car more enjoyable outside of the strip.

NmexMAX

iTrader: (22)

FYI, A34's are equipped with external EGR's. So I wouldn't say Nissan did it for that reason.

And that's one of the main reasons for better/more aggressive CVTC maps for autos since we have such tall gear ratios. 5/6MT, different story.

For clarification, hybrid isn't being discussed per-se. IMO, hybrid = VQ32.







***EDIT***

Jime showed some gains in his times.
http://forums.maxima.org/showthread.php?t=529464
http://forums.maxima.org/showthread.php?t=495197

And of course eng92's data:

http://forums.maxima.org/showpost.ph...8&postcount=59




Good reading
http://forums.maxima.org/showthread.php?t=262261

Matt93SE

iTrader: (44)

ignoring any of the BS in the thread, and just posting this FYI so you can see the effect of the VTCs.. May be same or different on the VQ, but here is is anyway..


VE30DE with VTCs enabled/disabled..


on the blue run, I grounded the VTCs so they're on or off or whatever... but you can see what it did to the high end. not cool. supposedly the VTC system is set up so it's supposed to add low end, not high end. obviously that isn't the case here.

scrhale

Looks like the dyno is reflecting VTCs stuck in the permenant timing advance. This is just a guess. I have seen Nismo and others talk about doing the 3.5 swap with timing in full retard it reflects exactly what this dyno shows, BUT INVERTED.

Either way, the above dyno proves that tuning can be done to factory VTC maps. You should NOT be able to turn VTCs off and gain HP as Matt did under 5K.

DasYears

on the ve the vtc's are only on or off, but with the vq35 they are continuously variable (i think we knew that). so you get the optimization through the entire RPM range, unlike the VE that only changes two preset angles

nismology

iTrader: (8)

Was talking in terms of dyno comparisons only.

scrhale

Oh ... well then I retract my previous statement. Either way, and I am not trying to sound smart or be a smart-***, but could someone explain why there were a couple of ponies gained with VTC off on the VE.

DasYears

well i think the green and blue are the only comparable graphs here, since it seems the red may have been before some mods or something. the blue and green i would consider dyno variation, heat soak or something else probly caused that small drop. they would be the same though because the cam profile in the green and blue are the same until the point where the vtc's switched, which seems to be somewhere around 4800. before that point, there would be zero difference in cam profile/adavance

Matt93SE

iTrader: (44)

If you're referring to my graph, the red was the first run after I put the car on the dyno. the engine was simply heatsoaked from the drive over I guess.
we made one run, let it cool ~7-8 min, then made another (green), then grounded the VTCs and made the last (blue) run ~7-8 min after that.

ajcool2

iTrader: (43)

Bumping this because its been a few years and we finally have a dyno from a full 3.5 swapped max to compare with a partial swap. Very interestng I must say. Different transmission types will make it hard to compare but its a start.