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Discussion Starter #1
dollars spent to improve mpg / hp. ?! Does one spend less than $1000 to do CAI, Z-tube, Crawford Plenum, U.R. pulley to acheive 300 - 325 HP & better mpg ( if you keep your foot out of it) or do you go for the Super Charger (stillen?) $5000+ with over 360 HP ? Primary goal is to improve MPG, while the fun side of me (why we bought FX) is to +hp. ...$2 bucks a gal. , oh man!
 

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Hmm, lets see: if you've got the cash for the supercharger (or an FX to begin with), why worry over a few bucks difference in fill up price? Go for the BOOST! It's what I would do. The king has spoken, now go forth and mod!
 

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With all the regular 35 mods you do not end up with 320-325 hp based on the 1/4 mile times vs the 45.So $5000 for a truer 350 is a better buy on the performance side.Mileage does not always deteriorate with boost because you can drive less hard and get same or better response.The hill where I do most of my testing,I can now pull off lazy and short shift at 4-4500 and hit the same mph mark I did stock.
 

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Discussion Starter #4
Huh? could you please get a little more detailed/technical , ...sorta lost me a little. we are talking about a $5000 difference!
 

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In another words, just go for the blower.
 

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Bacically, he was saying don't use ricer math. 20hp plenum, 12hp pulley, 6hp Z tube and 7hp intake don't neccessarily add up to 45 gained HP. I have all of those and in cool weather/lowhunidity/sea level, average 6.4 sec 0-60 (before the pulley), which is on par with what FX45 owners are averaging @315hp, so 10 HP or so (likely more since my car weighs a few hundred pounds less than a '45) are lost in the math somewhere. It IS possible that I did gain 35-40HP, but still have a deficit on torque compared to the '45; it's all a balancing act. Anyway, if you want performance, you have to be wiling to pay for it, both out of pocket for the mod and at the pump. I wouldn't use gas milage as a determining factor, anyway. With the bolt-ons, the change in gas milage is negligable and if you drive normally, your milage shouldn't be THAT bad whith the blower. Decide what you want in terms of performance and go from there.
 

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Also, the numbers are a bit confusing as well. You're trying to add the RWHP gains of the bolt-ons to the crank HP of the car. Lets use an example of an average 15% or so drivetrain loss for RWD (a bit more for AWD): that means my RWD FX is putting about 240HP to the rear wheels stock. If I add the reported RWHP gains of the bolt-ons straight out, I get 285HP to the wheels (remember it doesn't REALLY add up this way, though). Now look at the dyno chart for the Stillen on a 350Z: http://www.infinitifx.org/phpBB2/viewtopic.php?t=470
Nearly 340 RWHP; that's a 100 HP gain to the rear wheels over stock, not to mention the massive gain in torque as well. Looks a bit more attractive when viewed this way, doesn't it?
 

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Two points:
-On another site they had a track day at a Maryland drag strip.Modified 35s vs stock 45s and the diff was 1 second.Those incremental HP gains seem un realistic..gains true,but not that much or the 45 is under rated(AWD,and tighter gearing).This was the most enlightening test of the 2 that I have seen.Clearly the 45 is faster than the #'s would indicate
-Should not compare g-times!Some 45 have done 6.0-6.1.I do not compare mag times with each other...just same mag tests(same site/same equip)
-Back to being helpful,the area under the torgue curve is what truly matters and the blowers excell here.One big $ hit and get there or smaller doses and get better!You will feel a diff.either way.
 

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Point taken. I wasn't really trying to make comparisons, just point out that numbers don't always add up the way one would think.

To be fair, though, in the comparo you reference, the '35 was AWD, right? Plus, 1/4 mile time comparisons are quite a bit different than 0-60 comparisons. G-Tech times are fine to compare if you have the cars together on the same day, use the same unit and same stretch of road which I have done with my car compared to a stock RWD '35. Haven't done it against a '45 yet, but hopefully will soon.
 

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brnjugfx45 said:
Two points:
-On another site they had a track day at a Maryland drag strip.Modified 35s vs stock 45s and the diff was 1 second.
Here's the link to that thread. Bradical has an AWD 35 with popcharger and Z-tube. He drove the only 35 at the track that day. The three 45s all had nearly identical performance numbers.

Don
 

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Oh, yeah, I remember that one. Still have to try the brake fuse/power brake launch trick...
 

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Discussion Starter #12
so if we do go for broke , the super charger, does the stillen (root) still seem to be a better choice over the ATI pro charger? ... can you say 5GRAND!
 

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PINITI-FX said:
so if we do go for broke , the super charger, does the stillen (root) still seem to be a better choice over the ATI pro charger? ... can you say 5GRAND!
Sorry I cannot get to just reply!The famous 350Z dyno blower tests is so sadly flawed(graphs are pretty though).Roots is more bottom/mid range and centrifical blowers are mid and up.Pro has an intercooler(good) and Stillen I do not know(check ads and pics).I thought you had a year,someone may test!Both require lube changes and are plentiful in the marketplace.Both can increase boost further with pulleys,but the range does not change(there are bigger eaton's/stillen,but Stillen is not changing the size.The Stillen with a diff manifold may solve some of the stock manifold problems,but air under pressure does not flow like normally aspirated air.As you drive your 35 where does it need enhancement?
 

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Discussion Starter #14
brnjug, so when do you get close to lancaster again?
 

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If you go for the Stillen stage 2 ($5k), you get the intercooler. IMO, the power curve of the Stillen is better suited and more useable in a heavier SUV such as the FX than the centrifrugal blowers' top end performance, but it depends on what you are looking for personally.
 

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The Stillen stage 2 has a nice, broad flat torque curve. It makes about 90-95% of peak torque @ 2200rpm and peaks @ ~ 4200rpm, at this point the HP starts to rise to its peak to 6500rpm. I think it's perfect for a heavy car like the FX.
 

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The one thing that all of you are forgetting I think is the cost of rebuilding the motor after about 30-50k miles. With a 10.3-1 compression ratio, I just can't see a motor lasting that long with a blower.

Doing N/A mods, while they may not net you to max performance, definitely won't effect the long term durabiliity of the motor. If anything, they will help it.
 

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Golden Boy said:
The one thing that all of you are forgetting I think is the cost of rebuilding the motor after about 30-50k miles. With a 10.3-1 compression ratio, I just can't see a motor lasting that long with a blower.
Well, we've got two factory blown Grand Prix GTPs in the driveway, next to the FX. They've got 55 & 60k miles on them, and never had a bit of engine trouble. I think the compression ration on them is only 8.5:1, and I'm sure they were designed to handle the extra boost.
 

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Well, we've got two factory blown Grand Prix GTPs in the driveway, next to the FX.
The key word there is factory. A motor specifically designed and built to be blown is a lot different than a N/A one with an aftermarket blower. Compression ratio will be the big difference. A 8.5:1 CR is just about perfect for a blower. Also the fuel system is designed for it along with factory tuning and internal engine components. A piston and ring combination designed for a blown application will be significantly different.

What it really boils down to is this. If you add an aftermarket blower to almost any motor, do know that you have a ticking time bomb on your hand. Yes you will get great power and it will work fine for a while but at the same time make sure you are saving up for that new built motor :D
 

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GB's got a point; I hadn't even considered the fact that these aftermarket blowers don't restroke the engine.

(Do the VK and VQ share the same compression ratio?)
 
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