CJM: Ultimate 370z Fuel Pump Thread
 

Edit & Update: I have deleted the posts with data as they are outdated. I have a current PDF which is a format that is much easier for me to continually update and organize than forum posts are. Please find the PDF hosted here: Click Here

CJ Motorsports offers products and solutions to maximum performance of your factory 370z fuel sending unit. When your needs exceed the potential of the factory sending unit, we also have entire custom sending units to achieve any level of performance.

We manufacture and carry everything you need to perform all following modifications to your sending unit. If you prefer to have us perform the modifications for you, please contact me for a quote. We can work with your existing sending unit, or we can start with a brand new one and ship it to you complete.

I have decided to create this thread as a resource for the community. I expect it can be useful for customers installing our components purchased either directly from us or included in their forced induction system kit. I also wish to help the DIY'ers, as we have always supported that side of the community. You will find that most of the individual pieces from our kits/systems are available separately for customers who wish to custom tailor their own fuel system. If it difficult for us to make complete systems that will be a good fit for every single vehicle's own configuration, so we are happy to accommodate custom builds the best we can.

Reserved

Yes and Yes! When I decide to go E85 I will be giving you a call for the correct application for my setup and power goals!

So much win to fill one thread! Long overdue Charles! Subbing

Subbed since I'm helping install an Aeromotive this weekend.

Subscribed

This is good Charles this thread should be made a Sticky with more forum members starting to build there engines.

OK done with it for now... gotta get some other work done.

I just finished the instructions on putting a 400/485 in. Had a lot of questions on that lately so I wanted to get it out there. Especially because I have some customers that are about to do it and need the info!

This is a lifeline. Thanks for the info!

Charles @ CJM is seriously a wealth of knowledge and goes above and beyond when it comes to answering stupid questions. I should know lol. He's received probably a couple dozen from me alone haha. :shakes head:

Keep cranking out amazing products man! Thanks for helping out and supporting fellow Z owners everywhere! I can't wait to see what the S2 fuel system will do with our custom SC setup!

Thanks!

No, we thank you! :D

Phunk - I completed my fuel pump install over the weekend on my BP Turbo kit. Since you mention on the first page that you cannot confirm fitment on a G37, here's several pictures from my swap. Mine looked exactly like the one in Sasha's instruction manual. Hopefully they might help you. FYI...I have a 2010 coupe

http://i1155.photobucket.com/albums/...ps0b755d06.jpg
http://i1155.photobucket.com/albums/...psd097be4b.jpg
http://i1155.photobucket.com/albums/...ps2fc99d48.jpg

Good Job CJM

Thanks for sharing! I believe the G37 Coupe sending unit is the same with the exception of it being slightly shorter, maybe 1-1.5". If you happen to have not dropped it back in the tank yet, try and get us a tank depth measurement... then we will know for sure! If you already installed it, no worried, I will get the measurement from someone.

Charles

Setting up the CNC right now... once its running I will have a day or two to work on this thread more and also get back to everyone who has PM'd me

Already put it back together. I actually read your post after all the work was completed. Had the pictures handy so figure it might be helpful to you.

actually ya.. just looking at the picture i can tell that the chrome rods are shorter

Love this thread. MODs, please STICKY!

Added idle fuel pressure fix section. Put it together awfully quickly. Let me know if its not clear enough.

Added return conversion instructions for CJM S1 and S1.5 fuel systems or any other brand fuel systems that include the official CJM RCK (return correction kit)

I have another fuel pump module sent to me here right now to perform the works on, so I will hopefully have a chance to take the photos and post up the reverse flow return conversion and filter delete.

Hey guys, looking to drill out my Ventri for my new pump as suggested, what did you guys find was the best size to drill it out to? Hopefully looking to do it once. I know Charles gives a conservative but just seeing out of the guys that have done this with a 340 what did you find worked best for you?

Hi phunk, can you please check all your posts on page 1, all images disappeared. Also, the Install Manual link of the S1 Fuel System is broken. I am about to get the S1 kit for my TT preparation and need some install Guide.

Thanks :tiphat:

Not sure how I missed this post until now... I think this forum isnt sending the email notifications reliably lately.

If you take the link and add "host." in front of the URL, it will all work. Everything is moving around right now due to a new website. So the file is now at HERE

Awesome, many thanks :tiphat:
Gonna get my S1 kit with the AAM TT very soon.. cant wait:tup:

Phunk, can u plz confirm whether the Idle Pressure Fix is still needed with the CJM S1 Fuel Return Kit + AEM 320LPH pump? There is no mentioning of it in the Install Manual. (Assuming the FPR is correctly set to 52psi). Thx!

The idle pressure fix is needed for pretty much any upgraded fuel pump, but definitely one as large as 320lph.

The installation manual for the S1 system doesnt mention the idle pressure fix because it is not required for the return fuel system.

But it is required for the fuel pump upgrade that you are doing, with or without a return system.

I am working on getting all this stuff in PDFs and it will be slowly popping up in the TECH section of the new website.

Okay, and thanks for all the great work :tup:

Would you be able to update the photos on your thread Charles? It's not appearing correctly. This is some great info here.

Thanks.

It was all moved to a PDF on our website, in the tech section.

Just installed the CJM fuel tap with mini pressure gauge... My fuel pressure at idle at just over 60psi with my 255 lph pump.

What is the downside of not performing the idle pressure fix? Is it safe to assume I would need a retune if I did it?

That pressure spike is the down side.

You wouldn't need a retune if you fixed it. But you don't need to fix it if it's not causing a problem. It come right back down to spec as soon as you give it some gas. But if it's making you idle rich or giving you startup issues you might want to address it.

Thanks! The car runs fine so I will just leave it =)

I've been having start up issues for 2 months now after i upgraded from a walbro 255 to a aeromotive 340 fuel pump and is always when the car sits for hours and it never did it with the 255 fuel pump. I am starting to think i need to do this Idle Pressure thing to possibly sort things out but first i need to find that PDF.

I would recommend getting a fuel pressure gauge in the car so you can see pressure at idle and startup. This would help indicate if there is a possible problem there.

Phunk... this holiday I have been trying to fix my wobbly idle and thought I might as well do the idle pressure fix... I have pulled the fuel pump and drilled the venturi 4 times now - the last time with a 7/64" bit. Pressure at idle has only dropped to 59psi (and was only ~62psi before I started) and I am hesitant to keep drilling it in fear I may be doing something incorrectly. Is this out of the ordinary? Seems very large compared to the starting point you provide in your tech article. I am drilling all the way through the oriface.

I am running a walbro 255lph and reading the pressure from the mini gauge on my CJM fuel port.

Any advice you can provide would be appreciated! Happy holidays!

edit: Also wanted to mention I have 650cc injectors too.. otherwise the fuel system is stock. I also tried revving the motor up to 3.5k and the fuel pressure only dropped a few psi.

Might that not be the crux of your problem right there?

Perhaps a bigger pump and good regulator?

7/64 sounds large-ish to me for just the Walbro 255. If I found myself in your position, the first thing I would try is entirely removing the black Venturi from the bottom of the canister and reassembling (temporary). This way you can find out if there is any end in sight or if you might go larger until the component is entirely useless just to find it still didn't fix your fuel pressure spike. To take the part out completely will defeat the Venturi system but it will also answer a question, whether any size modification at all could even resolve your condition.

The idle pressure spike generally is only at idle and flattens out immediately when the throttle is touched, so I'm thinking your fuel pressure spike might not be coming from the Venturi system.

If you drilled out and it got you down a few psi, and then you drilled it a little more and it didn't go down more, than I don't think it's going to go down any more. It's a very sensitive setup and the slightest enlargement should have a measurable effect.

I suspect your stock fuel pressure regulator is backing up the return flow itself. But even in that case pressure should drop as soon as you touch the throttle. Which would lead me to consider the gauge is reading incorrectly or the regulator itself is regulating incorrectly.

Thanks for the response! I'll try removing that bottom venturi piece and report back. I appreciate your guidance!

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