http://www.350Z-TECX.COM/forums/inde...showtopic=9925

and replace the 'X' with a 'H'

 

I should have added that unless you have a much higher volume FI system, then boost is boost. As I've seen on here, the turbos don't seem to flow more air than the bigger superchargers @ the same boost level, that's what my comments are based on.

 

[QUOTE=BriGuyMax]

Boost is boost bud...no matter what's making it...QUOTE]

Bri, to clarify, this is not the case. PSI is measure of pressure, but not airflow. 12psi from a large turbocharger is significantly more mass air, than 12psi from a small factory turbo charger, for instance. Airflow makes power, not pressure. The mass of the airflow is the key factory in power production, not pressure.

 

[QUOTE=Sharif@Forged]Read the post just previous to yours...I already clarified.

 

I think someone is posting something about this already, but I've tried explaining this so many times that I had to vent a little and hope for someone to get it and use it when they are considering their FI setup.

BOOST DOES NOT EQUAL HORSEPOWER

Horsepower, wherever you choose to read it, crank, flywheel, wheel, etc..etc.. is due to the combination of components in between the point where you measure it, the method in which they are setup, and TUNING.

You can have all the goodies possible in your car, and have 300HP to the wheels, that same car could do anything between 300 and 1000HP.

Compression, A/F, Fuel Delivery, Air/Fuel Capacity, Tuning, Gear Ratios, Spring Ratios, Cam, Timing, valves, block setup, and about 50 other major parts and accesseries is what get you HP not FI, FI is just another part (only a faster way of getting there sometimes)

 

I agree with Sharif on this. In cases of exceeding the capabilities of the engine components (as opposed to just poor tuning), torque will eat up a motor faster than horsepower. I think that is why the SCs have a seemingly higher survivability factor. The torque curve on a TT is much more agressive and therefore potentially more detrimental to the longevity of the motor if not addressed correctly during tuning.

I've seen lots of posts stating "I was pushing X HP when my engine blew", but few that said "I was pushing X Torque". I think if the latter were analyzed, you would find much more consistency than looking at the HP numbers.

 

Torque = turning moment. Rods if they bend, do so under peak turning moment, not peak HP; so I'm with Sharif also.

Edit-> Sorry, rods will always bend a little as the crank will also twist a little during normal operation; I meant bend to deformation

 

[QUOTE=BriGuyMax]The current FI kits on the market have vastly different airflow production capabilities, which is why you see a pretty big spread in power, at a given boost level, between the various kits.

I am glad we agree, that power/trq is a function of mass airflow, rather than pressure.

 

yes, we agree.... and hopefully that boost does not equal hp, and boost is only measured in pressure.

We need a FI dynamics instruction book for the FI dynamcis course that we should make available a local campuses

 

Huh? I think you mistyped or lost me for a minute.

Boost is pressure, measured in PSI or Bar or whatever. Boost is not mass airflow...we just agreed that they were different. Mass ariflow can vary greatly, while pressure remains constant.

 

I didn't want to comment on this thread , but dude you are clueless ).

WRT
"and if for some reason your timing is way off, you will smack a piston with a valve..."

A few VQs have popped due to agressive "Ignition timing" which led to high cylinder pressures or shock caused by detonation. "Cam" timing is totally different aspect and current tuners have no ECU control of CAM timing on the VQ35. Spend a few years doing research to understand modern automotive technology and come back when you have a clue.

Geeeesh.

 

[QUOTE=Sharif@Forged]Not just that , everyone is tuning with differing octane maps and other ad-ons. Most Cali cars are tuned for 91 octane (more conservative timing) whch inherently reduces those overall dyno numbers as an average.

 

This is what happens when you are doing too many things at onces, on only 1 cup of coffee.....

I went back and edited my post, you're right... I typoed a thought.... I wanted it to read more along the lines that boost is not HP, Boost is solely measured in pressure, and a goal of FI is to provide greater mass airlflow which nets you hp/trq.....

How's that?

 

Sounds good to me!

 

[QUOTE=Sharif@Forged]However, a second order effect on tq. results from higher inlet presssures (boost) to the cylinders (force/load on the pistons)..The compression ratio x inlet pressure x the area of the cylinder head increases as the boost increases. The net force on the piston increases and walla more tq to the crank..

 

It's pleasing to see no Stillen SC have blown a motor! Makes me feel that much more comfortable as I am gonna order my Stage 2 in a year or so! :P

 

Just cause no one posted doesn't mean it has not happened. For a while people kept posting that only one vortech (booger's) had blown a motor and by reading this thead you see it's not the case.

 

I never said that boost equals horsepower. But I think you can agree that we have a basic hp range for a well tuned bolt on FI kit on a 350Z at a certain boost level. For example..at 5-6psi guys are typically seeing 330-360whp regardless of the FI kit, and and at 8-9 psi guys are seeing 400-440rwhp on average. I only questioned it because 440 seemed very low regardless of which FI kit they had and that it was odd to see an average whp level at such a higher than average boost level.

 

2 STOCK motors, 7 trannies, 3 clutches, 3 VLSD's, 1 starter, 1 battery, 3 coilovers, 4 bodykits, 2 doors, 1 rear hatch, 3 p/s window motors, 1 d/s window motor, 1 trans mount, etc...

have ~7k miles on 3'rd dealer installed motors and ~10k on latest trans... trans grinds into 1'st, 2'nd, 3'rd and 5'th, i think it's the worst one yet (with Redline MT90)

haven't had any issues with LSD/Rear end since getting KAAZ/3.9FD

right now the car won't start unless push started.. changed starter, battery, all fuses, checked wiring, ignition, immobilizer, don't know what to do next?

 

Um...sell your car..that's unheard of. Or get someone to steal it and wreck it...woops I didn't say that. :P