Jump to content
SAU Community

Recommended Posts

There is an excellent article in Autospeed this issue about airflow through the coolers and believe it or not, it has nearly SFA to do with the size of the front opening (grille area) that determins the amount of airflow.

It has everything to do with the amount of pressure in the engine bay and how successfully you disperse it.

Lift the back of the bonnet about a cm and you will be surprised how much difference is in the airflow.

I am getting a couple of the gauges that measure the pressures and do the tests myself and then I will let everyone know the outcome.

Hmmm,I understand what you say about the dispersion of pressure,but surely direct airflow would impact on the cooling efficiency of said coolers? :confused:

As in direct contact with cool air? I'm aware the (negative) pressurisation and ram-air style effects would feed the ambient air to coolers,regardless of frontal opening area,but I'm talking about increased eficiency by way of direct cool airflow contact? Or am I off target here? :D

  • Replies 2k
  • Created
  • Last Reply

Top Posters In This Topic

Hmmm,I understand what you say about the dispersion of pressure,but surely direct airflow would impact on the cooling efficiency of said coolers? :confused:

As in direct contact with cool air? I'm aware the (negative) pressurisation and ram-air style effects would feed the ambient air to coolers,regardless of frontal opening area,but I'm talking about increased eficiency by way of direct cool airflow contact? Or am I off target here? :D

Once the air pressure inside the engine bay equals the air pressure on the outside the flow through the coolers is ZERO and the only cooling would be on the front face and regardless wether there is a big hole or little hole at the front, the oncoming air is basically the same.

Interesting, i have raised the back of my bonnet 20mm, when i had the L24E it reduced my overheating problem considerably. My intercooler is hidden well behind my bumper, and i still manage to create frost on my out tank of the cooler, with less direct flow than you would think

Once the air pressure inside the engine bay equals the air pressure on the outside the flow through the coolers is ZERO and the only cooling would be on the front face and regardless wether there is a big hole or little hole at the front, the oncoming air is basically the same.

Hmmm,very interesting.I can understand wht you say here,but I would've thought that even with zero flow through a core,the bigger the front face exposed direcly to the air stream,the more cooling.Of course,with a 'small hole' at the front,the air would diffuse in and around the core,but I'd have imagined that it wouldn't be the same as high speed air flow hitting it directly??

Also,for interest's sake,how much benifit would a "big mouth'd" front bar that shows the whole intercooler be then? I'm guessing not as good as previously thought perhaps?? After reading your comments,I can see more advantage at lower speeds from direct flow,before pressure equalises.Direct flow at lower speeds should aid cooling in as much as reducing heat soak,whereas a "hidden" intercooler would be more pron to radiate heat,and that heat not be dispersed as effectivily,due to the low air speeds,and no great air diffusion occuring.

:headspin:

Thoughts?

Hmmm,very interesting.I can understand wht you say here,but I would've thought that even with zero flow through a core,the bigger the front face exposed direcly to the air stream,the more cooling.Of course,with a 'small hole' at the front,the air would diffuse in and around the core,but I'd have imagined that it wouldn't be the same as high speed air flow hitting it directly??

Also,for interest's sake,how much benifit would a "big mouth'd" front bar that shows the whole intercooler be then? I'm guessing not as good as previously thought perhaps??  After reading your comments,I can see more advantage at lower speeds from direct flow,before pressure equalises.Direct flow at lower speeds should aid cooling in as much as reducing heat soak,whereas a "hidden" intercooler would be more pron to radiate heat,and that heat not be dispersed as effectivily,due to the low air speeds,and no great air diffusion occuring.  

:headspin:  

Thoughts?

yeah its monday and who thinks on a monday LOL :D

Adam yes your car will have a speed sensor wire, as it should have a 180kmp/h limitere as well..As to what wire it is, ask the audience on that one

Hmmm,very interesting.I can understand wht you say here,but I would've thought that even with zero flow through a core,the bigger the front face exposed direcly to the air stream,the more cooling.Of course,with a 'small hole' at the front,the air would diffuse in and around the core,but I'd have imagined that it wouldn't be the same as high speed air flow hitting it directly??

Also,for interest's sake,how much benifit would a "big mouth'd" front bar that shows the whole intercooler be then? I'm guessing not as good as previously thought perhaps??  After reading your comments,I can see more advantage at lower speeds from direct flow,before pressure equalises.Direct flow at lower speeds should aid cooling in as much as reducing heat soak,whereas a "hidden" intercooler would be more pron to radiate heat,and that heat not be dispersed as effectivily,due to the low air speeds,and no great air diffusion occuring.  

:headspin:  

Thoughts?

with my fmic its mounted low to get the air through the 2 slits to the radiator, i've also raised the bonnet at the back to allow the air flowing across the bonnet to work as a vacume and suck the hot air out ofthe engine bay, in theory then allowing more air flow into the engine bay (thats how it works in my head)...my fmic and piping are all black to help with theat soke... :D

well i installed the Malpassi Rising Rate Fuel Pressure Regulator today and ran into several problems and now my car is ****ed atm.

i fitted the FPR and at first it was fluctuating heaps the pressure on idle. a few hoses were loose so we tightened those. took it for a spin and it had huge misfire again. found out it had one of the things on the plenum d/c one of them things that help it idle some air pressure thing or something ithink? not sure. but anyway i reconnected that and it idled a bit better went for a spin still huge misfire.

then on way back into my street smelt electrical burning smell. got into driveway could still smell it. anyway turned car off, properly hooked up that 2nd valve that was d/c, secured the FPR a bit better, turned it's pressure down coz i guess my injectors are dirty/****ed.

went to turn the car on and theres no power going to the fuel pump. i know this coz its not 'buzzing' so its not priming. car tries to turn over but no fuel. immobiliser looks fine, all the fuses in the box in the top left of the engine bay look fine, but car no go :D

sooooo i need an FJ20 Wiring Diagram. does anyone have one? i found the normal 2 pages that float round every website in Oz and theyre no good i want proper full wiring diagram. so i can try and trace the wiring etc to the fuel pump and to the ECU etc. really need it to narrow this down and try and find the problem. seems like its a burnt out wire somewhere i guess.

if anyone has proper wiring diagrams that'd be great. cheers

']well i installed the Malpassi Rising Rate Fuel Pressure Regulator today and ran into several problems and now my car is ****ed atm.

i fitted the FPR and at first it was fluctuating heaps the pressure on idle. a few hoses were loose so we tightened those. took it for a spin and it had huge misfire again. found out it had one of the things on the plenum d/c one of them things that help it idle some air pressure thing or something ithink? not sure. but anyway i reconnected that and it idled a bit better went for a spin still huge misfire.

then on way back into my street smelt electrical burning smell. got into driveway could still smell it. anyway turned car off, properly hooked up that 2nd valve that was d/c, secured the FPR a bit better, turned it's pressure down coz i guess my injectors are dirty/****ed.

went to turn the car on and theres no power going to the fuel pump. i know this coz its not 'buzzing' so its not priming. car tries to turn over but no fuel. immobiliser looks fine, all the fuses in the box in the top left of the engine bay look fine, but car no go ;)

sooooo i need an FJ20 Wiring Diagram. does anyone have one? i found the normal 2 pages that float round every website in Oz and theyre no good i want proper full wiring diagram. so i can try and trace the wiring etc to the fuel pump and to the ECU etc. really need it to narrow this down and try and find the problem. seems like its a burnt out wire somewhere i guess.

if anyone has proper wiring diagrams that'd be great. cheers

I think you may find what your looking for on fj20.com

']

sooooo i need an FJ20 Wiring Diagram. does anyone have one? i found the normal 2 pages that float round every website in Oz and theyre no good i want proper full wiring diagram.

The 2 pages you found were on the FJ20 website right? And what exactly do you have DR or MR?

HAHAHa just saw the last post..

Does anyone else have a turbo timer fitted that needed to be spliced into the speed sensor wire? If so, which wire is it? I had a look at the FJ20.com diagram but can't make it out.

And where could I mount the timer so that if I want I can still read it, but it can be covered up easily if I ever get pulled over. I was thinking of moving my head unit across to the left and then putting the turbo timer on the rhs of the big gap with a hinged cover above it or something?

Does anyone else have a turbo timer fitted that needed to be spliced into the speed sensor wire?  If so, which wire is it?  I had a look at the FJ20.com diagram but can't make it out.

And where could I mount the timer so that if I want I can still read it, but it can be covered up easily if I ever get pulled over.  I was thinking of moving my head unit across to the left and then putting the turbo timer on the rhs of the big gap with a hinged cover above it or something?

y dont you mount it between the centre console and your seat, above your sun visor.....in the ashtray!!

Guest
This topic is now closed to further replies.



  • Similar Content

  • Latest Posts

    • yeah first and reverse is where you will find clutch release issues (whether hydraulic or mechanical) because the difference in revs required is the highest there; particularly changing down from 2nd to 1st when still moving. To be clearer though, it is possible that the clutch release bearing is the wrong height. This is less likely than a hydraulic issue but it is not unheard of when you are mixing and matching
    • Quite right, if you make it to that pension you deserve every cent
    • Hi all, Restoring r33 series 1 rb25det. All the heater hoses were on their way out, have replaced them and put it all back together. After testing I noticed a small leak from behind the head on the actual metal water line to the turbo when cars warm. I tried running a longer hose over it but it kept leaking...   I am about to take the (stock) manifold off again😔 to change the water line does any one have any lines they recommend? I was looking at Aeroflow Turbo Oil & Water Line Set but not sure what everyone else recommends. Car is completely stock but want to upgrade turbo eventually. it looks like ill have to disconnect a lot just to replace these lines so if there's anything else recommended to do please let me know. Thank you in advance!
    • From memory, on the R33 GTSt at least, while everyone says "It's not adjustable", I found when I changed clutches in mine, it just needed a small adjustment on the rod length. But be very wary here, as you could end up trying to push the pushrod in the master too far, or blowing out the slave.   Most likely though, if the master/slave isn't bypassing internally or leaking out, then the throw out is the wrong height compared to the fingers on the clutch, so when it moves to disengage the clutch, it isn't 100% disengaged. You can check part of this out too by jacking the car up, having the engine running, put your foot on the clutch and try to engage 1st gear. If it goes in pretty easy (Compared to the ground) and/or the wheels start turning a fair bit and it takes a bit too much brake pedal to bring them back to a stop, this is likely the issue.  I'm not sure if you can adjust the height of the forks etc in these though, it's been that long since I've touched any RB gearbox.
    • That's all good, I thought I was missing some interesting feature! Maybe @PranK can double check if that is something that is meant to be operating or not.
×
×
  • Create New...