I just got off the phone w/ a guy i know and he can get me a 3.5 for $600. Then i called the shop i go to and they charge $750 just to swap in a motor(this is without modifying the 3.5). Then i started thinking and i figure i am going to have to lower my boost levels, get the car retuned, and get the ARP rod bolts. This starting to look to expensive at the moment, but i keep thinking about how sick it would be to go through w/ the swap. Can some of you give me some opinions on how much power a S/C'd 3.5 @ 9psi would net. Also would this be a safe setup since there is no way in hell i can afford another blown motor anytime soon

 

Hey Chris you may not have heard of me before but I can share a few comments and hopefully ask a few questions.

I have a VQ35 powered 4th gen with an '00 VI. If you ask me personally if it's worth it, I say hell yes. I have an SAFC II dyno tuned it etc and am now looking to get an SMT-6 to advance the timing. So to answer your question yes it is worth it. Also talk to Tilley, TILLEYS99 is his user name. He has a turbo setup with a VQ35 he recently dyno'd and got 354 WHP. INSANE!!! That thing is crazy fast.

Now to the questions, why do you think you blew your motor? I'm concerned about this because I will be advancing my timing soon and don't want to run into any issues.

 

Thanks for the insight

Man to tell you the truth i don't know yet. It could be a combination of things. My setup isn't that much more different than anyone on here except the timming which is stock. So that leads me to think it was timming. When i find out though i will deff let you guys know.

 

How much boost are you running? Stock motor, CC's of Injectors? What type of fuel management? I swear the VQs are strong motors I'm very surprised that bish blew.

 

geez man just look at his sig...

 

The ARP rod bolts are needed for high RPM abuse (I'm talking 7000-7200+) but on a boosted car I would personally play it safe and avoid problems by keeping the stock 6550 rev limiter. I doubt you'll need them if you don't go over 7k.

The 3.5 can take more timing than the 3.0 so you might be able to keep stock timing safely. I'm not 100% sure yet. We'd have to compare stock 3.0 timing to what the 350z runs stock, but there is apparently a pretty significant difference.

 

If you're gonna get rid of your blower, I got dibs!

 

 

I say go for it. I was gonna go that route but at that time when I blew my motor in the fall of 05, I wanted to go 3.5....at that time 3.5 swaps were just a few who innovated that idea like Tilley and such...now its a regular thing to do....be the first to be 3.5 S/C...I believe u have to swap out the time chain/ cover and such....Godspeed

 

Are we talking about a destroke 3.5(VQ32DE) that tilley has in his car or just a straight 3.5 with 3.0 timing chain. I have seen a general list of parts to accomplish the 3.2 swap but have forgotten what is involved with a 3.5 (fuel rail? TB? EGR?)... which of the two can handle more boost and power???

I'm looking into this since i forsee my motor eventually blowing. If a 3.5 doesnt take as much work (ie tearing the motor apart) then 3.5 would be a better route for me...

Sorry Chris if I hijacked ur thread. BTW sorry to hear about ur motor.

 

no prob, i am talking about just doing a straight up 3.5 swap

 

how would you incorporate the s/c in that setup?

 

use the 3.0 timming chain cover which the SC bolts on to

 

whats involved other than 3.0 timing chain for a straight swap? I would imagin a pathfinder tb and soildering injector plugs and rpm switch for VTC? I'm interested in this too any help would be great.

 

id have to imagine, that it would be a torque MONSTER. :-D mmm dooo iiitttt
btw, im sure ive told u more that once...and nows prob. not the best time, but god dam your car is gorgeous.

 

my injectors are direct drop in, the pf tb needs a adapter plate and i think you do need a rpm switch for the VTC

 

You cant keep VTC with 3.0 timing chain/sprockets, you have to loose the VTC setup if your going that route- plus the blower won't bolt up with the VTCs in the way.

 

ahhh yep forgot about that. Still learning how this **** works

 

^^^ me too, still learning.
with pull the 3.5 timing chain cover off and putting in the 3.0, does in involve pulling the cams or taking off the head...?

Lucky your injectors are drop in, I would need new 550cc and make it a return setup not returnless. I already have DW 500cc so I need to sell these if I decide to get a motor.

How much boost on stock internals do u think it would hold? for both ur sc and my turbo setup...

 

Let me ask you this- if the shop that you took it to, blew your engine from what it sounds like mis-tune (cut out and wideband in tail pipe ?) you going to trust someone like that with a engine build up ?

I dont know if you have a 2nd car to drive around or not, but I suggest you stick to a cheap 3.0L, as DE-Ks can be sourced for less than 400 bux at times. You could have your engine runing within 1 day if your mechanic is somewhat competent. Make sure to get the ignition retard working properly and veriffy it via timing gun and scan tool- you can do that with the E-blue. Or you will be doing another engine swap soon. I can pick up 10 deg of advance if I lean out my fuel maps in EU that I have, which in your case would most likely cause the engine to go.

On a side note- I had a similar misfotune happen to my SR20DET long time ago(98 I belive), as the injectors I got from Nissan Motorsports where not 555cc but 370cc. JWT programmed the ECU for a Z32 MAF and 555cc injectors. My car ran dangerously lean without me ever knowing it (never heard of wideband 02 anywhere around me)- it did run like azz thou. After bout a week of fuqn around the engine spun 2 rod bearings.

YOU CAN repair a rod bearing failure in few hours worth of work for bout 100 bux, that is if the crankshaft isn't scored up and the big end of the rod is still ok. You just have to match up the right bearings for your engine- FSM shows how and you Could possibly fix it...... key words here are - COULD possibly.

 

No the shop that tuned my car did a good job. They told me timming could be a issue and warned me of the dangers. I took it to another place to get it dynoed. We did this on a Sunday afternoon when the shop was closed. The tailpipe sniffer was putt on before he knew about the cuttout. We were going to use my in car wbo2 but it isn't working for some reason. I then told him we could still go ahead and dyno it since the car had been tuned several months ago and has ran perfect since.

Honestly mike i would rather just swap in a new engine being that mine has 85,000 miles on it and the 3.5 swap is not going to be that much more money. I can get a 30,000 mile 3.5 motor from a guy in town for $600. My shop said they would hook me up and install the 3.5 for the same price as he would do the 3.0. I think they are kinda excited to get a chance do it.

 

Be the first to do it. Although I would run lower boost... 12 psi is going to put out pretty ridiculous numbers on a 3.5.

 

Don't tell him that. Although he will need a 5MT soon enough if he does this.

 

Why?????

As long as he keeps timing/detonation in control, the VQ35 will take it and more.

 

i would like to keep everything safe this time, although i would like to go for some sick #'s. I guess i need to get a J&S

 

Then you need to retard timing. Buy the emanage timing harness.

J&S would add safety and with the knock gauge allow you to tune the amount of timing to eek out more whp.

 

Why would you need to pull timing? Stock 3.0 timing is overly conservative even for a boosted 3.5. How much timing are boosted 350z's pulling? Not that much. Running 93 Octane and stock timing on a 3.5 would be very very safe IMO.

 

He is scaling 510cc injectors through the MAF, which in theory advances the timing, how much...I don't know. He needs to excessively pull timing until he gets things sorted out.

After 6psi or so, 350Z guys are pulling timing especially above 6K rpm. How much is "not that much"? Sounds to me like 6-degrees or so from 20-25degrees total on TT setups...SCs should be less though.

 

Sorry to partially hyjack the thread, but how much power can stock 3.5 315 cc injectors take? And what about stock G35/350z 335cc injectors? It has to be in the mid-300 range at the wheels, right?

 

Actually per Shariff in this thread:
http://my350z.com/forum/showthread.p...ght=timing+ATI

Stock is typically 20-27 degrees, at 9psi 20-22 degrees is too much for 93-octane, and he says to shoot for ~15-18 degrees. He says he runs far less timing in the midrange/towards peak torque and then gradually advances it towards redline.

 

so i would have to drastically pull timming to start out with then work from there?

 

If you don't change anything, apparently not, since you've been running with the timing whatever it is for awhile. I don't know what caused your engine to fail Chris, we need more info. I'm just suspecting the timing, since that's the only obvious difference in your setup vs. others who have not had issues.

However, I'd hook up an OBD scanner or better yet a Consult and log your timing with the scaling once you get the new engine. Without knowing anything, I'd pull 1-2 degrees per PSI and then reduce it in the upper end.

 

you need to get this underway :-) if everything goes well, ill be doing the same thing.