http://www.my350z.com/forum/showthread.php?t=315828

 

http://www.my350z.com/forum/showthre...highlight=Javi

 

cosworth pistons=bottom end work
shortblock built by forged=bottom end work


looks like 295 (295<300) and very questionable dyno runs


nobody has said that you cant make 300whp, just saying its very very very unlikely without bottom end work

 

I stand corrected. Was just reading and saw it was at z1. Was also reading about the haltech stand alone picking up some good numbers.

 

You missed were I was talking about camphasing and VVT tuning. That is the only reason I posted that dyno.
And questionable how? Many people have achived 280hp with Boltons and tune

 

Where are his run files? Dyno conditions can be manipulated to inflate numbers. Why is it that one person can magically get close to 300WHP with just cams and other minor riff-raff while many others can't? I don't believe in factory freaks. The word I'm looking for is anomaly...

 

I'm still waiting to hear why FWD VQ's can't achieve these numbers with similar mods. Anomaly my ***, its called good part selection. Most Z owners are Ricers who do mods just so they can post NISMO in their sig.

 

It's not common in the RWD world so why would anyone think it's a walk in the park for a FWD VQ35 where the owners are naturally cheaper? No one said it's impossible, just pricey.

You're also flipping your script. You came into this thread saying that 350Z heads were better. You got proven wrong and now you're saying "if the RWD 3.5's can do it so can FWD 3.5's"? What happened to the Z33 heads being different/better? I <3 inconsistency...


In any case, no one here is reinventing the wheel. The info posted on the first pagina (by me) regarding the most important items has been repeated a few times by other people. Cams, dialing in the cam angle, (along with timing and a/f changes),headwork and a modified stock or aftermark IM will get you the bulk of the power. Bottom end building (primarily the rods) and balancing is so you can rev where the engine is happiest reliably and not for a few dyno pulls or 1/4 mile runs. Increased compression makes it easier to get there by adding power everywhere in the rev-range (>15WHP peak on its own).

 

Ok so I posted at 5 am and remembered wrongly that his was a DJ vs a DD. If it did 300 on a DD then it's probably higher on a DJ, as you said. I don't see an issue with his numbers, but his is a fully built engine, a long way from just bolt-ons. I'd like to see some/any 300whp Dynojet posts, SAE corrected.

Keep in mind that 295 number is STD not SAE corrected. And 280 can still be a long way from 300. Also, the VTC tuning (ie adding further advance on the intake) wouldn't likely affect the peak hp #, just bump up the midrange.

The reality, as DasYears and nismology have stated, based on the combined knowledge and experience in both the FWD and RWD worlds, is that it is difficult to get to 300whp without significant work. To my knowledge, hardly anyone has chosen to do this and shown solid proof.

No one's saying 300whp is impossible, but you implied it could be done easily on just a tune and bolt-ons, which so far has not been proven to be the case. Not that I wouldn't love to get 300whp out of bolt-ons...

 

What part of the engine would be at fault for failure in a higher revving application? I would never touch cams without a new set of valve springs.

For the record, what's the highest a stock VQ should have a rev cut?

 

It looks like either the 3 or 3.5L shouldn't really go above 7200 for extended periods due to them shaking the oil pump to death. Dandy ran into that at 7500-8K on a fully stock 3L minus the HR oil pump. I was talking to a Z guy earlier, actually it was the guy that owns the 303WHP Z, and he said he reved his car to 7500 fully stock. I don't know if that was just playing around but he probably didn't sustain the RPMs like I would.

Then the 303WHP Z1 performance setup has an HR oil pump and he revs to 8400. The difference is the Z33 has a fully balanced bottom end, and its forged.

Its looking like 280WHP is the max with out some custom work be it ITBs or internal work. Thats RWD or FWD.

The minimum Id do if I opened the bottom end would be high comp pistons, eagle rods, and a full balance to 10K rpm. That with a GOOD valve job and big cams and good headers gave 303WHP on a "low numbers" dyno.

That last 20-30WHP sure is a b**** lmao.

~Alex

 

Depends on your definition of "higher revving". The stock rod bolts are good to ~7100 RPM. Past that on a regular basis and failure is almost guaranteed. Upgrade to ARP rod bolts and the safe limit is ~ 7500 RPM. Wouldn't go higher than this without further modifications.

7100 RPM.

 

BTW, what's with this talk of the HR oil pump? No one has put one in a DE to my knowledge. DandyMax and Adam from my350Z used revup pumps. Don't know who started the spread of this bit of misinfo...

 

in that case, I should turn my rev limiter down a little. I typically take it to about 7-7200. The rev cut is currently at 7500, although I never take it there. When I dynoed, the guy took it all the way to the rev cut.

 

LMFAO I keep doing that! I always mean the revup pump but I just say HR. DOH!!

~Alex

 

Don't mean to nitpick, but if cams are aggressive enough you can gain top end power by delaying the retard. Rocks @ my350z proved this with his Tomei 272's. K that's all...

 

Interesting. Do you have pics of the dyno sheet at all? I'm curious to see what the curves look like that high on stock cams.

 

hehe that really peaked my interest too. I wanna see this.

1997GA16DE, when am I gonna see you again man, I might need your help in the fall when I crack my vq30 open and I do a whole new fuel system, cams, ecu piggyback and P&P on my manifolds.

 

There are several factors at play and each situation is different but sure I'll buy that, with longer duration cams and good head flow, plus resonance tuning effects in the exhaust primaries. Too much retard may start to hurt a little bit at high rpm if over-scavenging starts...

 

Are you referring to excessive cylinder blowdown?

The scenario I had in mind was improving dynamic compression.

 

That could be (ie too late an IVC with the long duration cam), but what I happened to mention was more related to the EVC (if it's extended too late, for too long an overlap), in that if there is a strong enough inertia tuning effect via the IM and exhaust primary tuned lengths, at high rpm too much overlap can start to hurt, by over-scavenging, ie drawing charge right out the exhaust, and especially with too late an EVC. To me a cylinder blow down issue is more a matter of early EVO (ie too much advance).

I mentioned the exhaust because I happened to be thinking about it at the time in the context of dual VTC, and it was more a general comment than specifically about his car, I keep forgetting most of the cars don't have dual VTC since I'm always thinking in a dual context... (my brain goes off on tangents like that and I forget to clarify certain things, gettin' old... haha)

Sooo... given that he only has intake VTC and keeping it advanced helped (while not changing the exhaust), then I'd agree that it's likely the DCR improvement responsible. I wonder if there would be any real improvement at a cam duration of 260ish though... perhaps not... might be still an early enough closing... hmmm.

 

I requested that XAT sends me a better copy of the dyno because I forgot to tell them to turn on the torque curve. Here's what I have:

Before and After tuning:


3 Final runs:


Video:
(RIGHT CLICK, SAVE AS 16.2MB)

 

I had a good idea what you meant but was confused when you mentioned advancing the intake cam since delaying retard would essentially increase overlap and exacerbate said overscavenging effect. Wasn't thinking in terms of exhaust CVTC.

Step away from the mudslide....

 

Oh yea, I requested that they change the graph to power vs. RPM rather than power vs. MPH. I think they're going to get back to me on Wed since the guy only comes in twice a week.

 

Good question. I think there's extra mid-range power to be had with some advance but I don't know about top-end since the JWT's peak (with no headwork of course) at or near the stock redline anyway. At least in the Z33 application...

 

Very possible but it also depends how much advance, and the timing of the suction wave would have a lot to do with it.. (ie need port pressure diagrams to see the full story)

 

Yeah I was talking about top end or high-mid (ie around the point the cam is phased back to stock retard)

 

I figured. The peak is so close to the full retard point there would be hardly anything to be gained. BTW, has anyone dyno'd S1's (or knockoffs) with SSIM/CVTC?

 

sorry im a newb i guess but what CVTC ? some sort of mod ?

 

Not that I can recall, but then again you know how bad my memory is.


It's Nissan's acronym for variable cam timing.

 

Ive seen many engine swaps in my day but for some reason the sentra vq35 swap STILL impresses me. I just love the whole concept of it, wolf in sheeps clothing. Would you ever sell that thing?? And wouldnt traction be a problem at 300whp in a fwd car?

 

Coming from a non-biased opinion (not that I know if any of you are biased, but this is in the All-motor section)...

You are going to pay a good amount to build the engine up.

It sounds like you really like the turbo idea, but at the same time like NA cars....

Well I am the same way, I really enjoy the feel of a turbo, the sounds, just everything about it (power on the fly).

I am currently in the process of Boosting my max (3.5 02 6-Speed) (btw, this is officially the first time I have posted this on the org). I am about $600 away from a finished project.

However, when I get done the boosting I am not going to be able to run the boost much higher then 10 lbs, so I am stuck, once again where I can't easily adjust power on the fly (boost controller) because of my motor, so I plan to build the motor up once I finish boosting the car.

From what I am reading for 300 WHP from everyone, you are going to spend more money getting to 300 WHP then you are if you boosted.

Right now we have spend roughly $2600 on my turbo setup, and I am not talking piece of **** stuff, and we have like I said another $600 (maybe $900) to spend, so that puts us under $3500 for a turbo setup that will support more then 300 WHP (Not dyno proven statement).

I am currently sitting at 229 WHP / 239 Torque (Adjusted)

My recommendations for you would be to go both routes that you want. Use each Option for the other...

i.e

Turbo the car, make sure that you are system is stable with a turbo running, get yourself some engine management ect ect ect...

and then build the motor up which in turn, depending on how you build it (going with lower compression pistons vs higher compression pistons if you were to stay N/A) to support more boost.

At that time, yes you are F/I but at the same time you have given your motor some care and taken care of building it up...

dollar for dollar N/A is going to cost you more

But, if you want my All-motor opinion, and willing to spend good money...

4.2x stoker kit IMO :-D

 

Main thing that I would like about an "all motor" car is people's faces when you tell them it's n/a and you just womped on X car. Another thing would be reliability, you will surely have less "maintenance," and things to go wrong with n/a than you would with f/i

.02