Vortech - 3rd time's a charm!
 

Wanted to update you guys on my battle with defective Vortechs, finally got the car back after Vortech #2 went bad, think it's been 7 weeks! The head unit was fixed (or "replaced", new housing, impeller, bearings) in 4 weeks, but we ran into a number of tuning issues when I tried to upgrade. Threw on the 2.87" pulley w/650cc injectors and encountered the notorious belt slippage problem on non-revups, had to get the GTM pulley mod. Then it turned out that I was making too much boost - 12 psi past 6300 RPM! :eek: So I ended up with a conservative tune, but it's still making some nasty power due to the insane amount of boost. We think the culprit is too much back pressure, since the only mod I have on the exhaust side is a set of HFCs. I see some headers in my near future. ;)

But man this thing is a missile, I don't have a hard number, because it wasn't taken above 6300 RPM on the dyno (safety concerns), but with my raised 6800 RPM redline (via reflash), I think it's safe to estimate that I'm a little past 400 whp, not too shabby for a 5AT!

I could use some advice from you transmission gurus though. I detected a hint of a problem even before my new setup (back when I was at 364 whp), I would occasionally slip during the 2-3 shift in D. It's gotten worse, FAST. There's a really strong jolt during the 2-3 shift, and last night I took it out for spirited back road driving, and during a 3-4 shift, the car completely bogged down, felt like I was coasting in neutral for about a second, then bammm, hard a$$ shift into 4th. Not looking good. I'm thinking it's either the VB, clutch packs, or VB and clutch packs. I do have a defective VB though, and I think my Infiniti service manager is willing to replace it (I match the TSB perfectly), but if the clutch packs are damaged I'm screwed (a la SGP built tranny, $$$$). What do you guys think, does that sound like a typical VB issue (on the brink of destruction)? I'm thinking the logical first step is to get the defective unit replaced, see how the new part performs, and if the slipping is gone, get it upgraded ASAP. If the slipping is still there though, I don't know...

theres a TSB for VB?...

ah... 06-07.

congrats on getting it all running! :biggthumpup:

12 psi is hardly insane. I run 15psi daily.

So if your tuner didnt run the car up to redline on the dyno, he just guessed about the tuning for the last couple hundred rpms? My 650cc injectors were running 100% IDC at the top before my RFS. Certainly wouldnt wanted my tuner to guess up there bc you can go lean very quick when your IDC is maxed and your fuel pressure drops like a rock.

That's a good question, all I know for sure is that the printed run was stopped early. I'm assuming they didn't make a wild guess for 6300-6800 RPM. But they did warm me not hit high RPMs for an extended period (i.e. a crazy highway run), which is fine because I never do that.

well u can log a run and check you IDC #'s your self. If you are seeing 100% idc, i'd just double your AF.

have fun!

Get the sgp or gtm valve body upgrade and see what you are missing...............and dont forget a trans cooler.

Already have a B&M cooler installed (had one most of my time FI). Once I get my defective VB replaced I'm leaning toward the SGP upgrade. I'm still scared the clutch packs may be damaged though. I'd really be surprised if 364 whp (313 ft-lbs) did that though. Keeping my fingers crossed! The one thing pointing toward the VB is that the upshifts seem to act up at the same time the downshifts do, so when I"m seeing behavior described in the TSB (lockup), if I give it a little throttle I slip. They seem to be in a coexisting worsening state.

how is everything going? good post. can you tell me more about the GTM pulley mod?

Not too bad right now, it's back in the shop for a rough idle and SES light, I'm guessing it's the notorious misfire code. Should be fixed soon though and I'm gonna try to get Infiniti to replace my defective valve body, we'll see where it goes from there, if my shifts are still messed up, probably means the clutch packs are damaged.

The GTM pulley mod is awesome man. Before my latest setup, I was running a 3.12" pulley with a gates belt, which supposedly was also applicable to the 2.87" pulley. When I upgraded to the 2.87 (and added bigger injectors), the gates belt started slipping like crazy on the dyno, I'd hit 10 psi, belt would slip, it would drop to 7-8 psi almost instantly and regain control, but it was pretty much untunable. Apparently this has happened to a lot of nonrevup guys. The GTM pulley mod is really a kit (dirt cheap now too), it's a new belt and small tensioner pulley - a picture is worth a thousand words:

http://i235.photobucket.com/albums/e...5/DSC03469.jpg

DIY at my350z:
http://www.my350z.com/forum/showthre...ght=gtm+pulley
Link to kit:
http://www.gtmotorsports.com/product...cat=258&page=1

thats weird, i run much higher boost and i dont see any slip. no gtm mod. just out of the box non-revup pulleys.

I think vortech musta redone the pulley config on the non-revup plates bc my belt is only 78.5" as well (gates 0785 compared to the 0795 that came with the 3.33 pulley)

upgrade your valve body. torque is the real killer when it comes to f/i so your vortech should be ok.

cool thanks man. i have heard about this but i have been happy with my boost. plus mad tickets so driving slow no need to dump money on power when i drive like an old lady.

but i think i will do this. keep me updated on yoru ride man. thx

I think Vortech did change the pulley configuration on the newer kits, when I got mine installed in July, a couple of people commented on how my pulley setup looked strange. From what I understand though, the slippage is kind of luck of the draw too.

Speaking of which, apparently my UTEC went bad, that's what threw the SES light, I'm like the failure man! :D

But damn, talk about customer service, TurboXS had a free replacement delivered in less than 24 hours, already back in the car with the map reloaded! My hat is off to them, incredible.

Next step is to fight with Infiniti to get my defective VB replaced, then I'm getting it upgraded, assuming the clutch packs are fine!