370z GTM Stage 2 twin turbo Stock block

esfourteen · 03-14-2012, 03:16 PM

Quote:

Originally Posted by roplusbee

Not form experience, but I would think an SC setup would be decent with a 7AT. I am curious about the pulleys now. I like the idea of reducing rotational mass. The purpose of underdriving the accessories it keep them from overloading? Never had a pulley before..................don't slam me, please!

reducing rotational mass in the drivetrain frees up power, your engine doesn't make more power but the end result is more power is transferred to the wheels.

The major issue with the pulleys is that they are aluminum and our crank is steel, they are basically welding themselves together via galvanic corrosion over time.

roplusbee · 03-14-2012, 03:22 PM

Thanks

Reality · 03-14-2012, 04:28 PM

Quote:

Originally Posted by esfourteen

reducing rotational mass in the drivetrain frees up power, your engine doesn't make more power but the end result is more power is transferred to the wheels.

The major issue with the pulleys is that they are aluminum and our crank is steel, they are basically welding themselves together via galvanic corrosion over time.

I would say that it results in the power getting to the ground "easier". I did not make any legitimate power.
I did 3 back-to-back baselines, Installed Pulleys and Made 3 more runs... No real life gains.
Same dyno, same day (within a few hours).

I totally agree with the crank pulleys fusing.. I know of this happening to 2 local z owners who were both boosted.

A note for FI z owners, would be to read up on harmonic dampeners when considering crank pulley replacement...
-Or engine go boom!

Mike@GTM · 03-14-2012, 06:49 PM

Quote:

Originally Posted by Reality

I would say that it results in the power getting to the ground "easier". I did not make any legitimate power.
I did 3 back-to-back baselines, Installed Pulleys and Made 3 more runs... No real life gains.
Same dyno, same day (within a few hours).

I totally agree with the crank pulleys fusing.. I know of this happening to 2 local z owners who were both boosted.

A note for FI z owners, would be to read up on harmonic dampeners when considering crank pulley replacement...
-Or engine go boom!

That's what we've been saying as well. We even have a video of us removing a fused crank pulley in our Stage 2 Supercharger Press Release thread and have touched on the issues that have resulted from harmonics. We've seen the catastrophic results of running an aftermarket lightweight pulley.

Also, while reduction in rotational inertia does help improve engine response, there are other factors to consider as well...like how long you want your engine to last.

roplusbee · 03-14-2012, 08:20 PM

Yup..........I will pass. Just curious about it..........

LafitteZ · 03-15-2012, 07:19 AM

Of all the pulleys sold and of all the cars with the under drive there are only a handful of cars with a problem and even less with catastrophic problem. I have 2 cars with them one for 6 years supercharged and now my turbo 370 for 2 years no problems. We have 150 members in the Louisiana z n g community and not one of us has had 1 problem with the pulleys and we've been using them for years and not just on zs. I'm sure most mods we can find someone with a nasty problem I mean look the autos are melting the trannys but not everyone it's happening to. It's the nature of the beast there's always going to be problems with something and compared to how many cars have the underdrive compared to how many have problems is veryyyyy low.

LafitteZ · 03-15-2012, 07:20 AM

Lets not eat peanuts because 1 out of 100000 are allergic. I mean same difference.

Nixlimited · 03-15-2012, 10:24 AM

The point is: for the very nominal gains, if any, why take the risk?

shaun66 · 03-15-2012, 12:39 PM

Watch the video it really makes you

like why am i doing this to my motor!

LafitteZ · 03-15-2012, 07:04 PM

Quote:

Originally Posted by shaun66

Watch the video it really makes you

like why am i doing this to my motor!

Yea I understand mabe im just a risk taker. Iv seen many engines blow to bits from FI. We still do it on the quest for more power and more speed. Im willing to take the risk then again iv had no bad experience with them.

Speedy · 03-15-2012, 09:50 PM

Quote:

Originally Posted by shaun66

Watch the video it really makes you

like why am i doing this to my motor!

I must be dense. What video?

Speedy · 03-15-2012, 09:51 PM

Quote:

Originally Posted by LafitteZ

All you 7at guys if y'all had a choice would y'all buy the auto again? I'm thinking about buying a g37 for the ol lady and I'll prolly boost it off the lot.

7AT NO DOUBT! I just ran a 13.080 in the 1/4 bone stock with crappy track prep on the stock tires and everything. Best MPH was 108. Are there 6mts beating those times bone stock?

LafitteZ · 03-18-2012, 11:20 PM

thats a damn good time speedy. the 7ats are wooping some *** in this new platform

Ron · 03-19-2012, 07:41 AM

Quote:

Originally Posted by Speedy

I must be dense. What video?

This is the post, videos at the bottom.

Quote:

Originally Posted by SAM@GTM

....

UNDERDRIVE PULLEY is a bad idea all the way around for few reasons :

- Despite what anyone says about this engine being internally balance and removing the harmonic balancer does not have any effect on this engine is totally false. So by removing the harmonic balancer (witch is made from two part metal and rubber in the middle bonding them together for the sole purpose of absorbing engine harmonics and vibrations ) you are destroying your engine .

- Further more by installing the lighter aluminum pulley, keep in mind that aluminum is softer then harden steel (crankshaft) you are also taking a chance of either killing your crankshaft or being unable to ever remove the underdrive pulley since with time it will weld it self to the crank. and here is exactly what happened in this case, So we had to remove the whole front end, radiator support, a/c condenser so we can put a big enough air gun to brake loos the bolt and still had hell of time to do so .

Also I'm quoting the same info from the web

please watch this videos

Z eliminator · 03-19-2012, 07:43 AM

7 AT 12.42 @114.3

all motor.

best 6 MT 12.29. 114.7 all motor.

Same mods.

03-14-2012, 03:22 PM	#122 (permalink)
roplusbee A True Z Fanatic Join Date: Dec 2009 Location: Killeen, TX Posts: 2,360 Drives: 2007 350Z NISMO Rep Power: 22	Thanks __________________ 2007 350Z NISMO #0618: Zerolift \| UPREV \| F.I. \| Greddy \| Competition Clutch \| Injector Dynamics \| Aeromotive \| Pioneer \| JL

03-14-2012, 08:20 PM	#125 (permalink)
roplusbee A True Z Fanatic Join Date: Dec 2009 Location: Killeen, TX Posts: 2,360 Drives: 2007 350Z NISMO Rep Power: 22	Yup..........I will pass. Just curious about it.......... __________________ 2007 350Z NISMO #0618: Zerolift \| UPREV \| F.I. \| Greddy \| Competition Clutch \| Injector Dynamics \| Aeromotive \| Pioneer \| JL

03-15-2012, 10:24 AM	#128 (permalink)
Nixlimited A True Z Fanatic Join Date: Aug 2009 Location: San Diego Posts: 1,235 Drives: 15 GT-R / 11 Prius Rep Power: 25	The point is: for the very nominal gains, if any, why take the risk? yoyoPR likes this. __________________ Car Sold! Pleasure being a part of the Z community. New ride: 2015 GT-R - 647 WHP / 641 WTQ (e85) & 543 WHP / 519 WTQ (91)

03-15-2012, 12:39 PM	#129 (permalink)
shaun66 Track Member Join Date: Mar 2010 Location: n Posts: 837 Drives: MB 370z 7AT Rep Power: 16	Watch the video it really makes you like why am i doing this to my motor! yoyoPR likes this.

03-19-2012, 07:43 AM	#135 (permalink)
Z eliminator A True Z Fanatic Join Date: Jul 2009 Location: Ontario Canada Posts: 1,659 Drives: 370 Z 7AT Sports Rep Power: 18	7 AT 12.42 @114.3 all motor. best 6 MT 12.29. 114.7 all motor. Same mods. __________________ 12.343 @114.14 . 4.5 stroker motor is now being built. Dec 1 2015.

03-15-2012, 07:19 AM	#126 (permalink)
LafitteZ Track Member Join Date: Jan 2011 Location: lafitte, la Posts: 698 Drives: 40th anniversary Rep Power: 15	Of all the pulleys sold and of all the cars with the under drive there are only a handful of cars with a problem and even less with catastrophic problem. I have 2 cars with them one for 6 years supercharged and now my turbo 370 for 2 years no problems. We have 150 members in the Louisiana z n g community and not one of us has had 1 problem with the pulleys and we've been using them for years and not just on zs. I'm sure most mods we can find someone with a nasty problem I mean look the autos are melting the trannys but not everyone it's happening to. It's the nature of the beast there's always going to be problems with something and compared to how many cars have the underdrive compared to how many have problems is veryyyyy low.

03-15-2012, 07:20 AM	#127 (permalink)
LafitteZ Track Member Join Date: Jan 2011 Location: lafitte, la Posts: 698 Drives: 40th anniversary Rep Power: 15	Lets not eat peanuts because 1 out of 100000 are allergic. I mean same difference.

03-18-2012, 11:20 PM	#133 (permalink)
LafitteZ Track Member Join Date: Jan 2011 Location: lafitte, la Posts: 698 Drives: 40th anniversary Rep Power: 15	thats a damn good time speedy. the 7ats are wooping some *** in this new platform

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