thawk408

iTrader: (16)

What does it say? I can see them.

Diesel350

iTrader: (6)

It's just a blank page with an advertisement at the top.

thawk408

iTrader: (16)

I adjusted the link, but let it keep loading. I think the site is running slow today.

Diesel350

iTrader: (6)

Oh ok. Now it's working. Not much of a gain with just the Crawford Plenum.

thawk408

iTrader: (16)

Considering that there was a 10rwhp gain close to redline, I would say it is a pretty good mod. Crawford plenum is a top end rpm mod and not midrange like MREV. Remeber we are modding a Z here.

Diesel350

iTrader: (6)

There's no real gain until about 6500. How many people are shifting at that point a majority of the time? Unless your highway racing all the time I don't see much of a benefit here.

Hydrazine

iTrader: (53)

Despite some pretty intense slaging, I always did a pretty good job of ignoring it in the past. And this is the first it got under my skin. It won't happen again. I don't want to have a bitter competition with anybody. It certaintly doesn't do me any good.

As far as the different spacers are concerned, I think the 5/16" spacer is clearly the best option for the 350Z. Its performance is not all that much different than the 1/2" spacer. Its huge advantage for the Z is that you get to keep the stock strut bar in place. And from all the strut bars I've seen, I like the stock strut bar the most. Its not the fanciest, but its able to put a preload on the strut towers. The preload (and how it applies the preload) is its advantage over the aftermarket bars.

If you were to drive a G35 C the only compromise with a 1/2" spacer is the engine cover and going coverless is not such a big deal. Some people want to keep the cover and some dont care about it one way or another.

If you were to drive a G35 Sedan, the 1/2" spacer fits good 99% of the time if you remove the thick grommets on the back of the cover. In this case, there isn't much of a reason not to get the 1/2" spacer.

The 5/16" spacer can be used on any G35 or 350Z for maximum stealth. It keeps the engine cover and strut bar on and you cant see anything when its installed.

There are several other projects in the works and they offer much higher potential but they will also be more complicated to develop. One was already rough prototyped and dynotested with really good results. These will take a little more time to bring to the market though.

Tony

thawk408

iTrader: (16)

It is beneficial in higher rpms when you are highway racing or road racing. After I put it on it felt like it kept pulling and pulled harder in the topend. Most people that mod the Z and want more power are going to go to redline almost everytime, if not everytime.

Diesel350

iTrader: (6)

Like I said unless your highway racing not much of a benefit. Most guys on this board are not shifting right at redline. I doubt very much that shifting at redline and shifting at 6500 will make much of a difference in overall straightline accerleration.

thawk408

iTrader: (16)

People that mod the Z to go faster and make more power will shift at redline. It is a given when the power to the engine continues all the way to redline, it just doesnt make sense to shift at 6500 when you still have power all the way to 7000. 500 rmps does make a big difference, just ask the guys with the 287hp motor that got the 7100 reflash.

Also, to me the benefits of the plenum seem to be present earlier then 6500. at 5700 is when the lines start to break apart and at 6300 there is is a decent gain. To me the plenum was beneficial becuase I shift at redline everytime when I race. If you want to shift at 6000 then it will not be as beneficial to you.

Diesel350

iTrader: (6)

So basically your saying that overall acceration will be better by shifting at redline then shifting at 6000? I highly doubt that but I will be doing some real world tests to find out.

GEE PASTA

You are so wrong. Road racers want a "Broad" power band. Anybody road racing at redline will not finish the race. And just a quick note about redline. Redline is where peak HP/Torque join in the upper curve. Not the rev limiter. More bad information based on butt dyno test's

thawk408

iTrader: (16)

I am not basing it on a butt dyno. If you look on the 12th page I have provided a dyno and in my sig there is a link to every dyno I have ever done with my car. On the rev-up motor the HP curve is a flat line from 6300-7000. You are telling me that this is not a good place to be while roadracing? When did I say something about the rev limiter?

The mods I have done have helped out the entire powerband.
Here is the dyno:
http://community.webshots.com/photo/...38370850lJWBTB

Green = stock
Red = stock + crawford plenum
Blue = mods in sig

GEE PASTA

Let me go back and reread your post's, I will show you or try to explain to you what you have posted so far. IM the one that said rev-limiter not you. Many people here think that just because you can rev your engine to 7100 rpms that is the redline, Grasshopper!
......................Pasta

thawk408

iTrader: (16)

If I am understanding you correctly, then you are saying that the redline is whatever rpm the maximum HP/TQ is produced? The defenition of a redline is the maximum engine speed at which an engine is designed to be safely operated. The peak HP/TQ is just where the engine produces its greatest power, but it can still have a redline past that. The rev-up motors stock have a 7000 redline with a 7200 rev-limiter I believe.

lowrider

iTrader: (3)

Well

It looks like they let the cat out of the bag.

http://www.sah2o.com/intakeproject.htm

Lou

GEE PASTA

Nope its 6600 rpms. But I have heard also its 6400 rpms. Most factory rated hipo engines tend to have there redline about 100 to 200 rpms just above cross over HP/TQ. I personally understand what you are saying and don't totally disagree with you. My biggest complaint is this car or cars have a 213 CI engine in what I would call a very heavy car. On a road course with a wide ratio transmission and holding the rpms up at redline you would have a winner.
With the gearing "Factory" You would be best off keeping you engine, As I would call it,(Under a bigger load) and shifting at the right shift points. My best guess would be around 6300 rpms. Give or take a few hundred rpms. There are many ways to tune a car for racing.
For me, and the weight of a Z or G, I prefer torque and keeping the engine under a full load.
Now on the other hand, I would like to tune my SBC for high end HP for the strip, and on a short course, tune for low end power, Long course high rpm power. We all are winners here because we are learning what works. On a quick note: The strain on an engine above redline
goes up so fast, its just not worth it to me. Pasta

thawk408

iTrader: (16)

Nope its 7000 on the 300hp motors and 6600 on the 287hp. On a factory engine the physical redline is where the red starts on the tachometer, hence the term redline. You are right that on most cars the manufacter makes the redline close to the peack power, becuase it would be usless to keep on revving and not make any power. But on the 300hp engine from about 6300-7000 it has almost a perfectly flat HP line. On a racetrack my peack power comes in at about 6300 and carries itself all the way to 7000. On the straight away you will want to redline the car becuase you are still in a useable powerband. If you shifted at 6300 this would put you at a lower power point in the powerband, then it would running it to 7000. This is called shortshifting and on some cars it might help, but on the Z I don't see the benefit, because its power is still carried even after the peak point.

sfarrah

iTrader: (4)

The cross over between HP and TQ on a dyno chart will always be 5252 rpms, so according to GEE PASTA the redline will always be 5252 + ~100 or ~200 on every car?? So by that definition an F1 motor or bike motor that can rev past 15,000 rpm's will have a redline of roughly 5500 rmp. No offense, but that's just funny. I think you have your definition of redline a little confused. Listen to tHawk408 when it comes to the definition of redline for a motor. Optimal shift points might be what you're trying to describe, but that has nothing to do with an engine's redline.

DaveO

My two cents:

"Redline" to me is the maximum safe engine rpm point as specified by the manufacturer. Nissan increased the redline from 6600 rpm to 7000 rpm for their new "rev-up" engine to take advantage of the top end power. They also strengthened the crank, rods, etc. to compensate for the additional inertial loads that the additional 400 rpm produces.

Some use the word "redline" to describe their shift point. This is often at, or 100-200 rpm above, the engine's horsepower peak or where it flatlines.

Here's what I'm doing. Based on several dynos, my engine's horsepower peak is 6200 rpm so I shift around 6400 rpm. Even though I could rev my engine to the factory 6600 rpm or even the TS 7100 rpm redline I don't. Why? Because above 6200 rpm the power is decreasing and the inertial loads are increasing expedientially. If my engine was still increasing power at a higher rpm, say 6800 rpm, I'd increase my shift point ("redline") to take advantage the additional power.