Notices
Engine & Drivetrain VQ Power and Delivery

Drilling engine required for pathfinder mod

Old 02-04-2019, 04:33 PM
  #21  
bealljk
Registered User
iTrader: (13)
 
Join Date: Apr 2010
Location: North Denver
Posts: 3,916
Liked 395 Times in 334 Posts
Default

^takes a big man to admit when he's wrong!

youre all good … keep doing the good work!
bealljk is offline  
Old 02-04-2019, 04:46 PM
  #22  
travlee
Master
iTrader: (8)
 
travlee's Avatar
 
Join Date: Jul 2011
Location: Texas
Posts: 37,556
Liked 5,887 Times in 4,054 Posts
Default

Maybe a closed system under pressure is the key, not enough pressure under atmosphere
travlee is online now  
Old 02-05-2019, 05:00 PM
  #23  
ChrisDe
Registered User
Thread Starter
 
ChrisDe's Avatar
 
Join Date: Jan 2018
Location: Lincolnshire, UK
Posts: 56
Liked 17 Times in 11 Posts
Default

Just in case anyone is still curious about this, a guy called Charles replied to a thread I started on facebook about this and they took some photos that show exactly how this is connected. The holes are quite high up in the sides of this area we've been talking about and coolant actually flows DOWN into that area, which is not something I'd ever considered at all, and explains everything.






After seeing this, looking back at my original photos and videos it seems really obvious now lol but yeah, end result is that all of the VQ35 engines are open in this area and the pathfinder mod does work as intended on all engines, not just US ones.

I've got to say though, it does make me question how useful the mod is... because the logic I've always seen people say is that the coolant goes to the rear cylinders and then has no easy escape route, so this mod adds that. As shown in the diagrams below:





On the blog post where those images were taken from, they say: "the coolant flows from the front of the engine to the rear cylinders and has nowhere else to go". Then regarding the pathfinder setup they say "If you follow the same flow, from the water pump and into the engine block, you’ll find that the coolant now has a “back door” out of the block". But I think the diagrams are very misleading and I can now see that the coolant flows up out of those rear cylinders and into the heads (just like all the other cylinders), and on its way some of it drops into this area that feeds the pathfinder mod thermostat etc.

So if this mod isn't actually adding a back door allowing coolant to escape that couldn't escape before, what is it doing? Also someone just pointed out to me that the HR and VHR don't even have this option (i.e. there's no blanking cap for you to remove and replace with anything else), so Nissan can't have thought it was that useful

Last edited by ChrisDe; 02-05-2019 at 05:23 PM.
ChrisDe is offline  
Old 02-05-2019, 06:36 PM
  #24  
OldManZ350
Registered User
iTrader: (23)
 
OldManZ350's Avatar
 
Join Date: Nov 2003
Location: Florida
Posts: 2,108
Liked 84 Times in 73 Posts
Default

Maybe it clogged.

Originally Posted by ChrisDe View Post
OK so after someone else here in the UK tested theirs and found water does flow through it, I tried attaching an air line to the main coolant hard line that comes out of the back of the heads and blowing a few psi of air pressure down there. To my surprise, the level of the water sat in this little area that we're talking about in this thread started to rise and fall as I turned on/off the air pressure. So it must be connected to the rest of the coolant system... which is weird because the water never drains out of there and also there's no bubbles when the level rises due to me blowing air through. So I don't really get how it's all connected especially as there's no visible holes, but it is and that's all that matters! So yeah, sorry for wasting everyone's time
OldManZ350 is offline  
Old 02-05-2019, 11:01 PM
  #25  
bealljk
Registered User
iTrader: (13)
 
Join Date: Apr 2010
Location: North Denver
Posts: 3,916
Liked 395 Times in 334 Posts
Default

Originally Posted by ChrisDe View Post
I've got to say though, it does make me question how useful the mod is...

On the blog post where those images were taken from, they say: "the coolant flows from the front of the engine to the rear cylinders and has nowhere else to go".

But I think the diagrams are very misleading and I can now see that the coolant flows up out of those rear cylinders and into the heads (just like all the other cylinders), and on its way some of it drops into this area that feeds the pathfinder mod thermostat etc.

So if this mod isn't actually adding a back door allowing coolant to escape that couldn't escape before, what is it doing? Also someone just pointed out to me that the HR and VHR don't even have this option (i.e. there's no blanking cap for you to remove and replace with anything else), so Nissan can't have thought it was that useful
Chris - I agree with most of what youre saying and I think this mod is helpful. Necessary? no, but helpful.

I think the diagrams are misleading too and I do think you're giving the coolant a 'back-door' or just a 3rd door to cycle through. Not that the OEM pump provides so much flow that the two coolant passages in the heads are insufficient but allowing coolant to find it's way out of the lower portions of cylinder jackets is a step in the right direction.

Ive learned not to attempt to think like an OEM ... I 'speculate' that nissan did not put this modification on the 350z/g35/maxima/altimas/murano/FX/M/etc because it was unnecessary and the cost of doing this to many many many vehicles outweighed the benefits. If it saved $100 per vehicle in materials/labor/warranty risk and was deleted from the 10s of millions of engines used between ~2003 and ~2008 that is a significant cost savings. We all know that cost was a serious factor when nissan decided to bring the Z back from the dead.

So to eliminate as many of these unnecessary mechanisms was a step in the right direction.

Last edited by bealljk; 02-05-2019 at 11:03 PM.
bealljk is offline  
The following users liked this post: bealljk
ChrisDe (02-07-2019)
Old 02-07-2019, 03:11 PM
  #26  
03ztrackfun
Registered User
 
Join Date: Jan 2019
Location: Columbus, Ohio
Posts: 17
Likes: 0
Liked 3 Times in 2 Posts
Default

Hello to OP and all contributing to this thread. I'm a new 03' 350z owner and have been lurking/reading as many relevant posts as I can over the past 3-4 weeks to learn about issues and improvements for our cars. Wanted to say this is one of the best threads from any car forum I've read... and I've read a ton... current and previous owner of OBS F350, C4 Corvette, SN95 Mustang Cobra as well as all the normal boring stuff I've own(ed)
This thread should be used as an example to which all threads should be structured; Great pictures, staying on topic, intelligent discussion and research; that's all any thread should contain. Thumbs up. I'll be checking back to see how this all concludes. I'm curious now that its established the coolant passage way and direction if the Pathfinder Mod actually aids in cooling the cylinders or heads to a useful degree? I suspect under normal driving conditions the P.Mod has no affect. What about in severe situations?
03ztrackfun is offline  
The following 2 users liked this post by 03ztrackfun:
bealljk (02-07-2019), ChrisDe (02-07-2019)
Old 02-07-2019, 03:20 PM
  #27  
ChrisDe
Registered User
Thread Starter
 
ChrisDe's Avatar
 
Join Date: Jan 2018
Location: Lincolnshire, UK
Posts: 56
Liked 17 Times in 11 Posts
Default

Originally Posted by 03ztrackfun View Post
Hello to OP and all contributing to this thread. I'm a new 03' 350z owner and have been lurking/reading as many relevant posts as I can over the past 3-4 weeks to learn about issues and improvements for our cars. Wanted to say this is one of the best threads from any car forum I've read... and I've read a ton... current and previous owner of OBS F350, C4 Corvette, SN95 Mustang Cobra as well as all the normal boring stuff I've own(ed)
This thread should be used as an example to which all threads should be structured; Great pictures, staying on topic, intelligent discussion and research; that's all any thread should contain. Thumbs up. I'll be checking back to see how this all concludes. I'm curious now that its established the coolant passage way and direction if the Pathfinder Mod actually aids in cooling the cylinders or heads to a useful degree? I suspect under normal driving conditions the P.Mod has no affect. What about in severe situations?
Yeah I've been surprised how many people are willing to take the time to go take pictures and videos to help get a good understanding of this, so big thank you to everyone that's done that.

As for checking back to see how it concludes though, I'd say it is pretty much concluded now. We know this passage is definitely connected on all of the VQ35DE and REVUP engines, and the only thing left is speculation as to how useful this mod is really. I can't compare overall coolant temp before and after doing this mod because I'm doing it at the same time as going twin turbo and changing loads of things so it would not be a fair comparison at all. I do remember seeing a shop post something about this mod lowering their coolant temps by about 15 degrees F if I remember rightly, but I'm pretty sure they were selling a kit to do the mod so you never know how trustworthy that is or how fair their comparisons before/after were.
ChrisDe is offline  
Old 02-07-2019, 03:33 PM
  #28  
03ztrackfun
Registered User
 
Join Date: Jan 2019
Location: Columbus, Ohio
Posts: 17
Likes: 0
Liked 3 Times in 2 Posts
Default

Thanks ChrisDE Yep, my guess is no benefit or need in normal driving even spirted driving to a mildly modified VQ. For your situation and the situation I'll be using my Z for would be nice to know if coolant temps are reduced during a 20-30 minute neck ringing track session.
Best of luck with your TT build.
03ztrackfun is offline  
The following users liked this post: 03ztrackfun
ChrisDe (02-07-2019)
Old 02-12-2019, 05:55 AM
  #29  
Cedric Guerin
Registered User
 
Cedric Guerin's Avatar
 
Join Date: Jan 2019
Location: Clearwater FL
Posts: 9
Liked 0 Times in 0 Posts
Default

Do people typically buy the whole kit from z1. I was thinking about pick a parting it off a pathfinder.
Cedric Guerin is offline  
Old 02-12-2019, 07:47 AM
  #30  
bealljk
Registered User
iTrader: (13)
 
Join Date: Apr 2010
Location: North Denver
Posts: 3,916
Liked 395 Times in 334 Posts
Default

Originally Posted by Cedric Guerin View Post
Do people typically buy the whole kit from z1. I was thinking about pick a parting it off a pathfinder.
I welded fittings on the cover plate and a bung on the coolant hard pipe, no thermostat.
bealljk is offline  
Old 02-12-2019, 02:35 PM
  #31  
Conway_160
Registered User
iTrader: (1)
 
Join Date: Dec 2012
Location: Pan Handle
Posts: 2,015
Liked 124 Times in 109 Posts
Default

Originally Posted by Cedric Guerin View Post
Do people typically buy the whole kit from z1. I was thinking about pick a parting it off a pathfinder.
I have one i'm not using i would sell you for way cheaper than Z1.
Conway_160 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Thomas.
Forced Induction
28
01-28-2016 09:19 AM
ttuberz
Maintenance & Repair
12
01-26-2009 01:53 PM
boma
Audio & Video
4
11-09-2005 08:43 AM


Thread Tools
Search this Thread
Quick Reply: Drilling engine required for pathfinder mod


Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: