My redline is set at the stock level--so 7k. I did think about keeping the ATI on and swapping to the stock SC pulley, some suggested this--but others suggested it would be better to have the smaller pully for more boost closer to the charger itself. I really don't know what to think. But now that the ATI is off and the stocker on, I feel it would be better to swap crank pulleys, otherwise I will be swapping two pulleys (although I could of saved $$ and time doing the SC pulley swap in the first place).

I would agree that not much time is spent near redline on the street for me. Also, I'm not too concerned about 10% at redline--this is with the Fluidampr though, if I decide to purchase one. The ATI with the 85mm pulley would be about 18% over at redline and would begin to overspin at 5900 rpm (which was my setup before with 12-13psi). So although I could save money by just putting the ATI back, this may be too aggressive. a bit too much, overspin too soon.

Then again, I really don't know what factors into HKS's stated rpm limit--whether it has to do with impeller/bearing longevity or other reasons. It has been suggested to me that there is likley some wiggle room/fudge factor. But how much? who knows.

I do know that I am just not happy with my setup as it is with the stock crank pulley. I am only getting ~8psi and 360whp/360trq. I'm not sure if it is because I have headers or the belts are not as tight as they should be, but I thought the Stage 4/5 kits were good for 9-9.5 psi--as you are getting. And having the 12-13psi with the ATI kinda got me used to that--I'd probably be happy with ~10psi and some more power, so maybe the Fluidampr will be the best choice--although I am tempted to put back the ATI--but dunno how I feel about 18% overspin at redline and initial overspin at 5900 rpms..

I've also thought about going with meth injection, but I really don't want to do with the hassle of install and refilling of fluid. I know it sounds petty, but I'm not really jumping on it, and would rather not do meth injection.

Decisions....No matter what though, it's going to be more $$$ and more down time

 

I'm jealous. I've had idle surge ever since I had the S/C installed and its really annoying. Sometimes more often than others, but I've never been able to get rid of it. I mean it could be caused by many things (vacuum leak,loose belts,dirty throttle body, electronics, tune, etc.) The one thing I have yet to do which may be causing/contributing to it, is cleaning the throttle body--which I plan to do soon-hopefully this weekend.

 

It's a process of elimination i suppose.

I did the install of the kit myself with a few friends, so it's good knowing that everything was done correctly.

Question, are you running the fcon that the kit came with?

If so, did you have it tuned? Or are you running the stock map that comes with it?

 

I am using a fcon-vpro and uprev reflash. Tuned by HKS pro dealer/tuner.

 

Those figures look a little low for 8psi? My car is making 380whp/350 ft/lb (DE engine) at 7.5psi but we've maxed out the MAF now

We have the same mods aswell

Mine is tuned with uprev & no idle surge issues

 

yea, I don't know what to think. Maybe my idle surge( or its cause) is causing me to not make as much power as I should. Maybe I should check for leaks, or do a compression/leak down test. I do have a revup and I thought I would be making more power than what I put down. Not sure if it makes a difference, but ambient temps were 90+F when the dyno was recorded. I hope my engine is not tired.

I ordered a Fluidampr today, and will have it installed and retuned and maybe check out the engine/exhaust for potential lekas. Hopedully I will be making more towards what I did before. I'm just not happy with 360/360 after being at 400/415.

Are you m/t or a/t? What kind of dyno was your numbers recorded at? Do you know if it was SAE or STD correction. Mine was a SAE corrected and a Dynapack--but this particular dynapack reads lower than most and when I went on a dynojet, it showed a difference of about 5-7whp

 

Manual car, numbers recorded on a dynapack hub dyno. Not sure what the correction is but I think its STD

 

I took a look at your dynos from your car thread, and correction factor says: DIN.

Correction factors are confusing especially when F/I at different altitudes imo. However it seems STD reads the highest, followed by DIN (which is very close to STD), and SAE usually reads the lowest.

see:
http://www.bikeboy.org/dynocorrectionfactors.html

Also see:

http://www.quasarelectronics.com/~dy...on-factors.htm :

"SAE-J1349 the one that seems to work best! And is used by lots of dyno companies as default.

DIN 70020 Also popular, and used by people who like bigger numbers! In a lot of conditions it gives figures a few percent higher than the rest."


So perhaps if your numbers were SAE corrected they would be very similar to mine

 

So a 8psi you are at 380whp/350 ft/lb. Thats not bad. At Z1 motorsports I did 370whp/350tq at 8.31 psi. Every dyno is different. I wish I could get to 390/370.

What Exhaust you all running. Test pipe or HFC?

Thanks

 

hmm. I wonder is running the GTM spec SC pulley has anything to do with the idle surge? Unlikely, but strange that both myself and cdox are having idle surge and we bothe are using the GTM spec SC pulley.

Ink is runnins stock SC pulley and no idle surge.

I wonder if the smaller GTM spec SC pulley is resulting in belt slip?

ItoZann you are running the smaller GTM pulley? Do you have any idle surge?

 

Those with the GTM spec SC pulley, can you verify the part number for the Bando belt that connects the idler pulley to the SC pulle? I am looking to get a replacement.

Also, what brand, sizes are you guys running for alternator and AC belts?

Thanks.

 

I am using the Bando 1060 on the supercharger. I got them from MR RIZK. You could try the Dayco 5070410. The Bando PK1060 is 41.73in, and the Dayco 5070410 is 41in. The Dayco 5070410 should work just find if you have a 85mm GTM Sc Pulley.

As for the others:
A/c side is OEM
Pw steering, alternator. I am using a Dayco 5060670 (6PK1700).

 

Thx. for the part numbers and belt info. You are using the GTM 85mm SC pulley correct? I am wondering if the smaller pulley may be contributing to belt slippage. I'm pretty sure my belt is currently slipping at higher rpms as evidence my my boost dropping and not making as much power. I will try to post graphs.

Maybe I should try the Dayco since its a little shorter than the Bando?

I'm kicking myself for not keeping the ATI and switching to the stock SC pulley instead of swapping to crank pulley, as this would probably lessened chance of belt slip b/c more belt wrap--but not sure on how that would effect spool/boost having the larger pulley on the SC..

Now, I've ordered the Fluidampr and plan to just swap the crank pulleys again. But the belt slip has me wondering... Is the smaller GTM pulley a big factor in getting boost sooner/more boost than a bigger crank pulley?

 

Hmm. I'm a little confused on your choice of the 1060 as what comes with the kit is the 1040 if you have the 85mm pulley. Since you are using the Stage 4, I am assuming you are running the smaller GTM spec SC pulley, so if you are running the 1060 belts, then that is 20mm larger than the belt that comes with the 85mm pulley?

 

As per the instructions the HKS comes with the Bando 7PK1060. See attached

you can also read about it here:
http://www.superstreetonline.com/tec...dynograph.html

They talk about, Install the last belt, 7PK1060, but check all of your belts' tension a couple hours after the installation is complete. Adjust as needed to match HKS' tension specs.

And you can also see a photo of it here:
https://my350z.com/forum/product-ann...er-system.html

 

Right, the HKS comes with the 1060, but that is with the HKS SC pulley (95mm). The GTM spec SC pulley is 85mm and comes with the 1040:

https://my350z.com/forum/6888804-post1.html



So if you are running the HKS 95mm stock SC pulley, then the 1060 is the recommended belt.

But if you are running the GTM spec pulley (85mm), the recommended belt would be the 1040 as that is what is supplied by GTM. The smaller pulley would require a slightly smaller belt especially with potential for belt slip.

So you are running the GTM spec pulley (85mm) with the 1060

 

Oh, got you. Sorry for the confusion. We were talking the same thing but to different directions.
But like I stated earlier. The Dayco 5070410 should work just find if you have a 85mm GTM Sc Pulley. The photo above is a 1040mm which = 40.94. The Dayco 5070410 is 41 inches.

And yes I am running the 1060 with my 85mm pulley. I may get the Dayco 5070410 when it start to get worn out.

 

^^gotcha. Understood. So how much boost did u see withe the 85mm pulley? One of your posts says 8.3 and another says 9.3?

 

On my last dyno I saw a peak of 8.85. My avg is 8.5.

Now my boost Gauge is saying 10. I think I currently have something wrong I feel. I have Nismo Cat back with Berk Metallic Substrate High Flow Cats and all of the sudden my car got quiet at WOT. I am staring to think I melted my cats.

 

Yeah, really happy with the figures, would have liked a bit more TQ but I'm happy for now

Exhaust is - DC Sports headers, Tomei test pipes, Ichiba Y-pipe & Greddy single Ti-C

I'm running the OEM belt for A/C & the belt that came with the kit for the ancileries (can't remember the number off hand)

I've got a 90mm pulley to be fitted & a smaller belt once I get around to sorting out a MAF.