370z Supercharger Boost Issues

Optimiser · 01-16-2022, 11:30 PM

Quote:

Originally Posted by DrBacon

I haven't really followed this thread but reading back it sounds like the shop definitely don't quite know what they're doing. I strongly suggest going somewhere else.

As described in one of your previous posts boost falling off before redline is 100% a direct symptom of belt slip. Since you already have an RPM belt on the supercharger side that is most likely not the issue unless it's extremely loose (try pressing on the belt with a finger, it should be pretty stiff with little to no movement). Looking back at your pictures your serp belt is way too long without that extra tensioner, I run that K071045 belt WITH the tensioner to take up the excess slack, and even then I've been recommended to run the K071040 belt instead which is half an inch shorter.

If you sort out the belt situation and it's still a problem, then it's the intake.

Also, what happened to your engine grounds? Were they relocated or did they simply delete them? They are usually attached on the frame near the supercharger and attached at the top of the engine where the supercharger bracket brace is.

I just double checked his pics and his engine earths are in the the stock position (hidden behind tubing)

DrBacon · 01-17-2022, 01:28 AM

Quote:

Originally Posted by Optimiser

I just double checked his pics and his engine earths are in the the stock position (hidden behind tubing)

Oh that's interesting it's on the opposite side for RHD cars I guess? Never knew that

pkxu123 · 01-17-2022, 01:30 AM

My car is not with me atm but hopefully I get it back from the shop soon. They saw my email about the car running lean and knocking and called me to bring the car in last Wednesday. Haven’t heard back from them yet but hopefully they are making good progress.

Will keep you guys updated

THE BULL · 01-19-2022, 11:28 AM

One of the things I would check are your MAF jumper harnesses since the signal is a shielded wire and the jumper is not. It's possible you might be having MAFs sending an incorrect signal

However being that it's a reputable shop and BYthabay has tune many of them stick with them. Hope you get this resolved.

pkxu123 · 01-19-2022, 11:54 PM

Quote:

Originally Posted by THE BULL

One of the things I would check are your MAF jumper harnesses since the signal is a shielded wire and the jumper is not. It's possible you might be having MAFs sending an incorrect signal

However being that it's a reputable shop and BYthabay has tune many of them stick with them. Hope you get this resolved.

The shop ordered a brand new Stillen extension harness for me as it was missing in the kit but ill have a look at it.

Got the Topgunz anti slip pulley in but it still made the exact same boost. So it's probably not the belt or pulley that's causing the boost issue?

Not too much of a mechanic head myself but I do still want to get this all sorted...

Anyway, regarding the tune, we're having an issue now where the maps will randomly disappear. The first time it happened, I brought it back to the shop and they flashed the maps on it again. I drove it home the same day and it disappeared again on the second start up.
The shop suspects it's the ecutek bluetooth dongle so they took it back to their shop to analyse it. They flashed the maps back on again yesterday and it hasn't disappeared yet.

DrBacon · 01-20-2022, 12:25 AM

Quote:

Originally Posted by pkxu123

The shop ordered a brand new Stillen extension harness for me as it was missing in the kit but ill have a look at it.

Got the Topgunz anti slip pulley in but it still made the exact same boost. So it's probably not the belt or pulley that's causing the boost issue?

Not too much of a mechanic head myself but I do still want to get this all sorted...

Anyway, regarding the tune, we're having an issue now where the maps will randomly disappear. The first time it happened, I brought it back to the shop and they flashed the maps on it again. I drove it home the same day and it disappeared again on the second start up.
The shop suspects it's the ecutek bluetooth dongle so they took it back to their shop to analyse it. They flashed the maps back on again yesterday and it hasn't disappeared yet.

Take the intake tube off and run it filterless for a pull. Process of elimination by taking away potential variables.

pkxu123 · 01-21-2022, 06:48 AM

Quote:

Originally Posted by DrBacon

Take the intake tube off and run it filterless for a pull. Process of elimination by taking away potential variables.

I’ll get the tune sorted out first then will check if the intake is the issue. Still a couple of things that needs fixing with this set up unfortunately

pkxu123 · 03-08-2022, 07:53 AM

Update on post

I took it to another shop for diagnostic

Immediately, within a couple of hours they found the cause of the rattle AND the issue thats causing boost restriction! Amazing!

Soon as they took the bumper off, they can already tell that the intake was the problem. They did a dyno run with the intake on and off. With it on, they only saw around 5psi of boost. After they took it off, they immediately saw 10.

The shop that worked on the car initially custom fabricated the intake so I gave them a call and they were surprised that it was causing that much of a restriction.

And now the rattle…. They chucked it on the hoist and found that the right cat is defective… something is internally loose. Been advised to do a warranty claim.

Will keep this thread updated soon as I get updates…

NissanTracker · 03-08-2022, 06:43 PM

Quote:

Originally Posted by pkxu123

And now the rattle…. They chucked it on the hoist and found that the right cat is defective… something is internally loose. Been advised to do a warranty

I can tell you that I've blown OEM cats and high flow cats on my supercharger set ups on a couple of occasions. Especially if running rich. My current fix is running resonated ART pipes and moving the Cat cells further down the stream. (Suggested by Seb @specialtyZ).

I haven't installed them yet, but I'm hoping to lower temps as well that is causing timing to get pulled when IAT's climb in WOT. Should have some logs in a couple weeks + retune for it. I'll post results

Elmo370z · 03-08-2022, 08:52 PM

Need a better intercooler, and probably downpipe. Air is getting backed up at wot causing your IAT’s to shoot up. Such a common issue with everyone here.

Spooler · 03-08-2022, 10:39 PM

Quote:

Originally Posted by Elmo370z

Need a better intercooler, and probably downpipe. Air is getting backed up at wot causing your IAT’s to shoot up. Such a common issue with everyone here.

Your close but not quite right.

370zMelb · 03-09-2022, 06:04 AM

Quote:

Originally Posted by pkxu123

Update on post

I took it to another shop for diagnostic

Immediately, within a couple of hours they found the cause of the rattle AND the issue thats causing boost restriction! Amazing!

Soon as they took the bumper off, they can already tell that the intake was the problem. They did a dyno run with the intake on and off. With it on, they only saw around 5psi of boost. After they took it off, they immediately saw 10.

The shop that worked on the car initially custom fabricated the intake so I gave them a call and they were surprised that it was causing that much of a restriction.

And now the rattle…. They chucked it on the hoist and found that the right cat is defective… something is internally loose. Been advised to do a warranty claim.

Will keep this thread updated soon as I get updates…

So are you going to bring it to a new shop or have the old shop fix the intake and get them to retune it again?

If I were you, I would just demand a refund and take it elsewhere. Seems like you've had nothing but trouble and dishonesty through this shop.

pkxu123 · 03-09-2022, 06:45 AM

Quote:

Originally Posted by 370zMelb

So are you going to bring it to a new shop or have the old shop fix the intake and get them to retune it again?

If I were you, I would just demand a refund and take it elsewhere. Seems like you've had nothing but trouble and dishonesty through this shop.

I called the shop but the owner wasn’t in the shop. The front desk has told me he will let the owner know and I will receive a phone call from him. Been 2 days and I haven’t received anything yet…

At this point, I’m probably leaning towards a refund so I can get someone else to sort it out if they’re not willing to.

TopgunZ · 03-09-2022, 08:59 AM

Get the 4" S&B velocity stack/turboguard and add 2 Filterwears 6" filters. Problem solved.

pkxu123 · 03-11-2022, 06:01 AM

Quote:

Originally Posted by TopgunZ

Get the 4" S&B velocity stack/turboguard and add 2 Filterwears 6" filters. Problem solved.

Will this severely reduce the life of the motor/blower?

01-17-2022, 01:30 AM	#33 (permalink)
pkxu123 Base Member Join Date: May 2021 Location: Australia Posts: 29 Drives: 2017 Nissan 370z Rep Power: 28	My car is not with me atm but hopefully I get it back from the shop soon. They saw my email about the car running lean and knocking and called me to bring the car in last Wednesday. Haven’t heard back from them yet but hopefully they are making good progress. Will keep you guys updated Optimiser likes this.

01-19-2022, 11:28 AM	#34 (permalink)
THE BULL Base Member Join Date: Apr 2021 Location: Florida Posts: 217 Drives: G37S Rep Power: 26848	One of the things I would check are your MAF jumper harnesses since the signal is a shielded wire and the jumper is not. It's possible you might be having MAFs sending an incorrect signal However being that it's a reputable shop and BYthabay has tune many of them stick with them. Hope you get this resolved. Last edited by THE BULL; 01-19-2022 at 11:32 AM.

03-08-2022, 07:53 AM	#38 (permalink)
pkxu123 Base Member Join Date: May 2021 Location: Australia Posts: 29 Drives: 2017 Nissan 370z Rep Power: 28	Update on post I took it to another shop for diagnostic Immediately, within a couple of hours they found the cause of the rattle AND the issue thats causing boost restriction! Amazing! Soon as they took the bumper off, they can already tell that the intake was the problem. They did a dyno run with the intake on and off. With it on, they only saw around 5psi of boost. After they took it off, they immediately saw 10. The shop that worked on the car initially custom fabricated the intake so I gave them a call and they were surprised that it was causing that much of a restriction. And now the rattle…. They chucked it on the hoist and found that the right cat is defective… something is internally loose. Been advised to do a warranty claim. Will keep this thread updated soon as I get updates… 2011 Nismo#91, Optimiser, DrBacon and 1 others like this. Last edited by pkxu123; 03-08-2022 at 04:14 PM.

03-09-2022, 08:59 AM	#44 (permalink)
TopgunZ A True Z Fanatic Join Date: Jun 2012 Location: Minneapolis Posts: 2,651 Drives: 06 350Z , 09 370Z MT Rep Power: 6833	Get the 4" S&B velocity stack/turboguard and add 2 Filterwears 6" filters. Problem solved. pkxu123 likes this. __________________ ROTREX SUPERCHARGER TUNER KITS - $6799/ CUSTOM STILLEN AIR TO AIR KITS -$2100/ 700+ WHP!! WWW.TOPGUNSPEEDWORKS.COM

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