JCat

iTrader: (4)

I've seen pictures of the rods, and they just look weak.

Of the engine failures that have occured, have the rods been the weakest link?

Is it correct to conclude that the 350Z would benefit greatly if it had stronger connecting rods? ...Would they be forged? ...pistons too? ...

What is currently available? Are they the best solution, or has that yet to be developed?

....any trade-offs (i.e. balance)?

Sharif@Forged

iTrader: (92)

The failures I have seen were head gaskets and rings. There was one person...I cant remember who...that actually threw a rod through the block.

I honestly dont know if there is a "weakest" link, becuase the failures have occured in numerous locations.....not just one. That said, I agree the rods look very wimpy and skinny, and no question, forged rods and pistons would be a great idea....there is no point in changing one without the other. If you tear the engine apart, change them both...and maybe a few other things.

One other note, the failures were consistnetly a result of too much timing advance and/or lean A/F. So I dont think its the F/I alone that is causing this...its the tuning. You'll recall the ATI kits didnt have timing provisions, so some folks were blowing up motors even witih stock boost and a 12.5:1 A/F ratio.

JCat

iTrader: (4)

I've blown many head gaskets (Fords, testing compression limits), and usually it was a repair that did not ruin the engine.

When a Z blows a head gasket, is it worse?

I've busted rings too, and gauged cylinder walls beyond repair.

Does the 350Z have sleaves that can be swapped-out?

SQUILL

Yes the Z actually has nice sleeves from the factory which can be swapped.

As far as the rods being the weak link ....with perfect timing and a/f ratios in therory the rods should give out before the rings/gaskets/pistons will when the overall compression level is to high within a F/I application.

However it seems to me that the real weak link is proper tuning of the engine as all the motors that went stemed from poor tuning and or timing.

here is a pic of the stock VQ block

JCat

iTrader: (4)

Since both of you emphasized tuning and timing.......

How much control do we have over the ECU? Can we tune it absolutely, or does it have logic that resists tuning?

Is timing adjusted via ecu programming?

Can we adjust ecu settings at different rpms, temperatures, loads?

Is there a must-read on how this all works?

Sharif@Forged

iTrader: (92)

With tuning...you have three options...none of which are cheap....

1) Technosquare Reflash. This is the most stable way to make changes to the stock ECU, since you are physically reprogramming the ECU. This procedure costs $595 and is a one time shot..no changes to boost, timing, etc...are feasible....unless you reflash again...or take higher risks by increasing boost without reflashing.

2) eManage (cheapest solution): This is included in the Greddy kit and give you lots of control over what the injectors and timing are doing. It does about 90% of what a stand-alone does. It's limitations are that since its a piggyback, you are still relying on the stock ECU maps...which we know tend to vary..and can be finiky...and then the eManage adds or subtracts from those. For 10-12psi, I think this is a safe and reliable solution. Another limitation is that the eManage has problems controlling significantly larger injectors than stock...although some have got it working with 700+cc injectors.

3) Stand Alone ECU: Phunk is working with the HKS stand-alone, and its seems to be everything that everyone could want. It is pricey though..at about $2000...I think...he can confirm that..with tuning and stuff. These types of stand-alones allow you to keep all the cool features of the stock ECU, such as all the power windoes, ABS, speedometer.....stuff like that....but the stand-alone totally runs it own fuel and timing maps, and totally disregards the stock ECU maps. This is cool!

JCat

iTrader: (4)

It's not as simple as bolting on an Edelbrock manifold and a 750cfm double-pumper anymore.

Thank you for taking the time to explain these options. You have an excellent talent in that you understand what forum users are courious about and are very good at explaining or relating what you have learned. We appreciate it!!

You have decided on emanage, correct? Any concerns? Are you confident it has or will provide you with everything that you need in respect to tuning your particular set-up?

Sharif@Forged

iTrader: (92)

For my purposes the eManage is pretty good solution, since I doubt I will exceed 450whp on a stock motor anytime soon. I think its more than sufficient. I can add IPW, and retard timing, and view all the inputs/outputs in real-time on the profec-01. you can tune it with a laptop too. The only concern I have its that even if perfectly tuned, the tune can change based on the mood of the ECU....since the eManage is piggybacking off whatever the ECU spits out. So most people will tune in an extra level of safety, so that if the ECU starts getting aggresive, you'll have a bigger margin of safety.

If I decided to build the block, and really turn up the juice, I think the stand alone is the way to go. Hopefulliy by then, AEM will have completed their plug and play stand-alone. The big advantage is that it is totally user programmable, and you dont need to take it to an authorized tuner to get it worked on....its totally unlocked...which allows great flexibilty...or....a big disaster...LOL,

Right now, I am working on improving the robustness (is that a word?), of my fuel system, So far, all I have done is dropped in the Walbro 255. I still need an FPR plug and to install my Aeromotive FPR and return line. I think that will have to wait until I move to Charlotte in a couple of weeks...not enough time.

Good luck with whatever you decide!

Dr Bonz

iTrader: (1)

gq_626

You didn't mention the J&S Safeguard unit. What is your opinion on it? (I realize it is just for timing and it doesn't control fuel).

I have one but it isn't installed. As you probably know, I also have an ATI SCer. In your opinion, should I go with the TS ECU flash for FI or should I use the J&S (or perhaps even both?).

I plan on going with a larger fuel pump and injectors and ditching the ATI FMU eventually. I may even consider the 9 lb pulley. Any recommendations? It would be nice to get close to 400 WHP (I'm around 360-370 now)

Thanks.

ImportPartsPro

iTrader: (512)

Actually that is *not* a stock block. It was taken from our site and is an Upgraded block that has been bored out and has 8.5:1 Pistons.

SQUILL

Hmmmmm i copied it of this site from someone else that posted it here quite a while ago.

Are the sleeves the factory sleeves or have they been replaced or upgraded?

Sharif@Forged

iTrader: (92)

The J&S is another good option, I just havent seen too many installations on the 350Z yet. There were some issues with overheating coils as well, when I discussed this with John. I they are solved, but I'd like to see a few more good installations on the 350Z before making an assessment.

And correct...it only does timing, so you'll still need one of the above options to do the fuel.

spazpilot

iTrader: (2)

SGP I would guess

derek_i

Kyle,

Is that AEBS or something different? If different, please post some info.

-D

G3po

iTrader: (8)

my vote: the block shown has OEM sleeves .020 overbored with SRP 8.5:1 forged pistons. Can't be sure about the rods, but I bet they are the Pauters that SRP sells.

Definately not AEBS, since the sleeves are OEM and block deck has not been "closed". (closed deck is n AEBS tell tale sign).

SQUILL

i second the vote!

APS

No doubt the connecting rods are the 1st mechanical FUSE and if you exceed 500 Horsepower (real Horsepower at the Crank) a strong set of Billet con rods and forged pistons would be considered a mandatory upgrade if you want to avoid serious engine damage down the path.

Peter

APS

G3po

iTrader: (8)

So APS , what you are saying is that your TT dynos at 430rwhp are at the top of the recommended edge for reliablity with the OEM internals? Of course one big fudge factor is "real" drivetrain loss and the dyno used to measure.

APS

Yeah I believe that up around the 500 Horsepower flywheel power (approx 450 horsepower dynojet wheel power) is starting to get into the RED zone for the con rods at the factory RPM limit.

Of course a piston could also fail 1st through continual detonation and then the con rod would cause horrible damage to the cyl block, so one would need to diagnose which component failed 1st - either way you end up with a real mess.

Bottom line if you are going to get really serious with power (500+ HP) a good set of billett con rods and forged pistons would be an ideal upgrade.

Peter

APS

JCat

iTrader: (4)

What is the difference between billett (I could not find definition of billett on internet) and forged?

Are there "better" wrist pins available?

Should the wrist pins be the floating type?