[geeyoutoo]

I seriously doubt you will find any significant flow advantages with a metal fabricated snorkel on a ZD30. I have an early DI with an original safari snorkel on it, I measured the various internal diameters and found it was smaller than the later models which concerned me, I did a lot of testing and came to the conclusion going bigger was not going to make it go better, I have done many mods to my std airbox which did make a difference, but doing a test on the air quantity going into the airbox showed no issues at all. My old girl puts out pretty good Hp and torque, I know I wouldn't gain anything.
My 2 cents worth on a favourite topic.

 

[geeyoutoo]

Hi Ross, I knew you would come up with a logical answer. I still have to install the 4" airbox that I have, but cant do that until I have the connections sorted for the fender(wing).
This is why i asked the question. My thoughts were a safari style snorkel should be fine. So feel that you have clarified this for me.
The safari snorkel is also substantially less than a Fabricated metal style snorkel.

Absolutely it is, and I can assure you that a fabricated steel snorkel on my engine would make absolutely no difference, there is a lot of this type of thing, ie, several months ago as a project I removed the 2 3/4" 200 Cat dump pipe from my Beaudesert system and replaced it with a 3" straight through dump, the day before I did that I took the old girl out to my regularly used flat test road and did a 60-100k run in 4th gear, as soon as I fitted the 3" straight through dump I did the same thing at same place, no bloody difference whatsoever, now that one did surprise me a bit.

 

[geeyoutoo]

Is it that surprising Ross, if the remaining (and longer) part of your exhaust stays in 2-3/4 ?
In addition, isn’t a portion of the global back-pressure possibly generated by your VNturbo exhaust turbine and its vanes ?

The consensus among many is the CAT is a restriction, I wasn't sure so set out to positively find out, a possibility maybe, proved wrong thankfully, my question answered, as said I was a 'bit' surprised, not a lot.

My EMP is within spec.

 

[geeyoutoo]

@jono6974 just to get back to the ZD30 situation, simple maths that I've pointed out many times over the years. The 4.2 and the ZD30 utilise the same airbox and same snorkel (when fitted) all things being equal, boost etc, the 4.2 requires 1/3rd more air in std form to operate at any given rev. Once I realised that I saw it as pointless to spend any more money on the inlet side other than my own mods, ie, open up airbox intake to spread airflow over a wider area of the filter, also it is highly beneficial to have at least 30mm clearance around the air filter to maximise airflow, using a K&N or even gooderer a BMC gives you that clearance. I now get dirt and insects stuck in the airfilter for 360 degrees. Mine goes OK, I'm not at 200rwhp but I'm closer to it than I am to 150rwhp 🙂. I was never interested in max Hp, just good torque down low giving me great driveability.

 

[geeyoutoo]

hi Ross, yes i have noticed that the td42 and zd30 use the same airbox.
as i already have a fatz airbox which has not yet been fitted, i just want to maximise the intake as much as possible.
In saying that i saw some footage on a tuning website that claims the original airbox flows more air than most aftermarket airboxes.i believe this was due to the filter placement creating turbulence on its flat end as the air hits it.( but that is not my field of expertise)
As mentioned before i am not one for cutting holes in things, i think of holes allowing water ingress and rust to develop.
I could just fit the fatz airbox without the snorkel, but would need to figure out how to make the connections under the fender( I have not even looked in there yet)

Cool, it is all up to what you want, that is the important part. Removing the underguard parts is challenging Lol.

 

[geeyoutoo]

Hey, lets not forget the biggest reason we have snorkels, it is not performance, simply water crossings, I've had water over the bonnet, can't do that without a snorkel. When we had this argument many years ago about forward/backward snorkels I played around with the snorkel head on mine, so easy, forwards, sideways (to pick up air ramping up windscreen) and backwards, did I notice anything in drivability, no way.

Relate drivability, I've said in other conversations I've run 30psi on my eclipse, and yes my tune can handle it, got dyno numbers, same dyno at 25psi saw a drop in Hp, could I feel it driving around in my normal fashion, no, I did tests 60-100k in 4th and no tangible difference.

The biggest complaint I hear about rearward facing snorkel is the drumming sound wives don't like.

My 2 cents worth.