jonnylaw

iTrader: (3)

fyi for the guys with the HKS kit, the instructions call for changing out air filter every 1300 to 1900 miles!!! Not sure if this is the same for the 3 layer dry type, as the kit comes with the 2 layer wey type. Both supposedly should flow about the same, but the 3 layer type should have slighly better filtration, but not 100% sure. Filters have MSRP of $20. Mine was on for about 3500 miles before I just swapped it out, and it seemed pretty dirty. The G's location of the filter is also below by the bumper, so I assume it may be exposed to more contaminents, even with the metal shield and plastic undertray. So I went with the 3 layer dry type for the moment. Not really sure which type is better. I guess a real test would have to be conducted to find out, lol.

cdoxp800

iTrader: (12)

thanks for looking jonnylaw. I know mine is 6600 currently. That's to be safe till I get a Full Tune with a PMAS.
The whole Hot start issue I am having is killing me right now. I thought about pulling fuel to see if that helps. Each time I get gas the Car will not restart. It's just a pain.

pez1111

iTrader: (2)

Hey jonnylaw
Do the cosworth intakes leak ? I imagine this would be under boost conditions. Did you need to do any thing prior to installation to fore go that issue, and did you require a intake spacer to run the larger injectors?

Good luck with your re-toon and i appreciate your inputs into this thread.

Cheers

jonnylaw

iTrader: (3)

Actually the leak(s) I had with my first plenum, were more noticeable at idle (vacuum leaks), as well as on the dyno. I had a plenum from the first casting batch, and I guess there was possibly some issues with the o-ring grooves being machined too deep. It was sent to Cosworth and even with new endcaps, would leak. So after a few weeks, they sent me an entirely new plenum from their newest casting. I was told no sealant/lok-tite was needed to provide a leak-free seal on the plenum. So the new plenum was assembled and installed per Cosworth's instructions.

So far, I have not noticed idle surge (which what was happening with the first plenum due to the vaccum leak(s)). So I am assuming it is not leaking so far. I should know for sure when I go in for my retune.

No spacer is needed when installing "stock size", but larger flowing injectors, like Deutshwerks--they are plug and play and many use this brand. Other brands like RC may require spacer--but go with DW and you won't have to worrk about clearance issues

jonnylaw

iTrader: (3)

You are revup, correct? You are just waiting for a upgraded maf for tune for safe high rpm?

Are you using a dampened crank pulley like the ATI or the Fluidampr? Or are you planning to use the stock crank pulley?

Thanks.

jonnylaw

iTrader: (3)

This got me thinking...I am worried the blower may be overspinning.
I am worried about overspinning the blower.

I purchased the stage 5 SC kit and the ATI crank pulley--part number 918588. ATI lists the OD diameter of that part number to be 6.78" (~1" bigger than stock ~5.7"):
http://www.atiracing.com/products/da.../damnissan.htm

From other's measurements, the GTM higher stage 10 psi pulleys are ~85mm (~3.35").
https://my350z.com/forum/8285566-post77.html

From HKS website, the GTS7040 has a 9.444 drive ratio and a max impeller speed of 110,000 rpms.
http://www.hksusa.com/info/?id=3767

I have a revup engine, so my redline is 7,000 rpm.

When I plug these numbers into an impeller speed calculator like the one found here:
http://www.928motorsports.com/servic...ingpulley.html
the impellar speed at 7,000 rpms shows 133,738!

The impellar speed would be passed its max limit around 5800 rpms and would be ~23,700 rpms higher than the max limit by redline. If this is correct, than the blower is overspinning, throwing the flow out of efficiency range, and possibly causing damage to the bearings/shortening the life of the blower?

I was thinking adressing the crank pulley might be good, while leaving the SC pulley as it is. Although I would rather have a true dampened crank pulley on the car, if I put back the stock one (~5.7"), the impeller speed at redline would be ~112,435 at redline. If ATI can make me a custom crank pulley slightly smaller than stock (~5.6"), the impeller speed would be (110,462) at redline (if the calculator/figure are correct).

Any thoughts/sugestions?

jonnylaw

iTrader: (3)

Although I am still waiting to hear back from ATI about a smaller diameter pulley, I'll likely put back on a brand new oem crank/seal/bolt, and have the car retuned like this. This will keep the blower in its efficiency range, it would not overspin until 6800 rpms. As long as the oem's dampening effectiveness is adequate for 400whp/400trq, this may be the most cost effective and readily available option for me.

_ink

iTrader: (2)

Hi Jonny,

Might be worthwhile if you get in contact with this company:

http://www.rosstuffbond.com.au/metal_jacket.html

http://www.rosstuffbond.com.au/pdfs/ross-mjcat.pdf

cdoxp800

iTrader: (12)

Great find. Looks like they have something for the VQ.

VQ35 - 306230.

No size indicated, but a phone call can clear that up.

jonnylaw

iTrader: (3)

^^thx guys. I'm going to e-mail them since they are in Australia about the one for our cars. I need to know the diameter.

ATI told me they can get me a 5.5 od for $500 and it would take a couple of weeks. But, I'd want to keep stock size (5.75) if possible. Will see what the Ross diameter is. If bigger than stock, will likely order new stock oem pulley.

cdoxp800

iTrader: (12)

I got a Reply.

jonnylaw

iTrader: (3)

Wow, so this is the only stk diameter size dampened crank pulley for our engines (as far as we know)

but not available for 12 weeks..darn

_ink

iTrader: (2)

I have verified this information being located in Australia, its slightly easier for me.

I spoke to Ross himself, and he advised that it can be as early as 8 weeks which is still quite long.

But i'd recommend that you install the stock one back on. BTW, is the the 4 ribbed or 6 ribbed pulley?

Also, what exactly are the benefits of this to our SC cars?

jonnylaw

iTrader: (3)

hmm. well 8 weeks is better than 12, but still may be too long for me to wait. Also, the price seems to be about $550 US, given currency rate exchange.

I'm assuming the S/C is driven off of the 6 rib pulley as the 4 rib is for the a/c I think. Can anyone verify? So Ross confirmed that the actual outside diameter on his pulley is 5.75" (same as stock)?

The benefits of a harmonic dampened pulley is that is prevents harmful damage to the crank and components due to torsional vibration that can occur at high rpm or more load like in F/I. I'm not sure if 400/400 demands a true dampened pulley like the ATI/Fluidampr/Ross, or if the oem one is safe enough for these power levels.

At $190 for a brand new OEM one, I am leaning towards that direction, plus its readily available. I've got about a month before I can have it swapped out and redynod, however.

jonnylaw

iTrader: (3)

Ok so the actual price of the Ross unit is $670 AU dollars or ~$620 US dollars.

ATI can make me a custom dampened pulley of the exact same specs for ~$700 and would take 60-90 days, perhaps less.

Either way, unless Sam@GTM recommends otherwise, I'm going to put on a new oem pulley on and retune.

IanP

iTrader: (2)

Are you planning on selling the ati pulley? If so I might be interested

My car has gone away for mapping today

jonnylaw

iTrader: (3)

I'm still waiting to hear back from SAM@GTM for his suggestion on what I should do, but according to the impellar calculations, I should take the ATI off. If I do this it will likely be right before my dyno appt (~1 month away). Then yes, it will likely be up for sale. I will pm you before I list the unit for sale. One thing to keep in mind is your impellar speed. If you have the out of the box HKS kit and a non revup (6600 redline), you could likely use the ATI and gain a few psi without overspinning the blower, but check an impellar calculator to make sure.

Hope all goes well with your turn

IanP

iTrader: (2)

Mines a non revup with a stage 2 GTM kit, so 7/8 psi

_ink

iTrader: (2)

Hey Guys,

Does this kit use the stock MAF housing? Or is this not used?

jonnylaw

iTrader: (3)

The housing is not used-the maf sensor is plugged in on the HKS cast intake pipe (on the g35 coupe kit--not sure on the Z).