Thread: Teaser of the Week!

I'm giving up on trying to share knowledge acquired over 30+ years of racing, engine development and researching physics and theories of fluid dynamics.

BUT...

IF you had the engine, on an engine dyno, unloaded without the rev limit it has in these vehicles you may reach the limit of flow but there are other restrictions in the system that will affect flow well before (from the start of low in fact) before you reach Vmax of flow. Any ribbed section will create increased laminar flow and make any section effectively reduced in area reduced in size by an amount greater than that which a plain section will be affected at Vmax.

Then look at the power/torque curves of the engine. There's no need to be running it at high RPM's and so reaching areas where flow will be an issue as optimum numbers are well in the mid range of operations.

This topic comes up it seems in every discussion about snorkels. Have a look at the primary inlet on say a RRC or D1 with either the square or round filters. Looking at the square one, off the front there's a bellmouthed tube thats, by comparison to the rest of the inlet tract tiny, BUT, it works because the bellmouth (trumpet curve at the inlet edge) works to increase Vflow and so overcomes the limitation of size (faster flow vs slower larger vol flow). Probably also has an effect on what happens inside the airbox (haven't seen detail on in there) in terms of pattern of flow, distribution of air and so dust particles across the entire filter face, so reducing loading the filter in one place and relying on a smaller area for filtration and having flow restricted by the dust loading in that area of the filter.

Please, without malice, ill will, il feeling and with all respect. Just fit it, you won't feel it in the seat of your pants. You will feed cooler air (albeit compensated by the ECU anyway), cleaner air and keep it out of the water. Which I'd give up "perfect" flow for any day.

Originally Posted by FANTOM P38

Well I checked today & my stainless snorkel pipe is done, just need to get in there to pick up hopefully before weekend so I can have another play to work out mounting locations for A pillar & cut out gaurd & bonnet

This I gotta see! Text me when you know when you are gonna do it. I will pop over for a sticky beak and moral support when the gas axe comes out!!! ;-)

Originally Posted by DT-P38

This I gotta see! Text me when you know when you are gonna do it. I will pop over for a sticky beak and moral support when the gas axe comes out!!! ;-)

No Gas axe here Dave! Patience & some careful measure cut & grinding I think. Then I'll need to check double skin for gap on back edge of bonnet!

After taking a second look under the guard this time with the liner inserted i think i will be mounting the Snorkel on the outside all the way from the front and to hell with it. Thanks Danmal i didn't check with liner fitted just thought it followed guard arch i have included two end on pictures with the guard and liner in place for you all to check. Very tight squeeze through the middle section. And mine must be the poverty pack Steve i only have a single exhaust pipe which was 2", it now has a 2 1/2" and only one muffler to bring out that wonderful V8 sound.

Regards Gippy

Originally Posted by Gippslander

After taking a second look under the guard this time with the liner inserted i think i will be mounting the Snorkel on the outside all the way from the front and to hell with it. Thanks Danmal i didn't check with liner fitted just thought it followed guard arch i have included two end on pictures with the guard and liner in place for you all to check. Very tight squeeze through the middle section. And mine must be the poverty pack Steve i only have a single exhaust pipe which was 2", it now has a 2 1/2" and only one muffler to bring out that wonderful V8 sound.

Regards Gippy

Hi

Yes the middle section is the bit we are all exercising our "little grey cells" over, it's bloody tight in there!

Personally I am not interested in, or expecting, any power increase. My aim is simply to improve the wading abilty of the P38 without effecting the performance.

The way I see it if we can maintain a minimum of around 44 cm sq cross section then that will be fine.

Pretty sure I have a 2" exhaust as well and yeah the rear muffler is gone on mine as well

Steve

I just did some measuring for all concerned here are the results using inside caliper and digital caliper to take readings. First is the inside of my MAF at its smallest point (70.40mm), second set are of opening for inlet in guard vertical ( 60.00mm) and then horizontal ( 107.12mm) the air filter housing has a rubber insert to go through the opening into the air space created above the wheel arch so it is a little smaller.

Gippy hope it helps for those making components.
Couldn't get all photos in will make another mail

Last photos hope they help the last two are of the inside of the guard air filter box.

Gippy

Gippy

Thanks for all that work

It seems either the later models or maybe it's the 4.6L had a different airbox, MAF etc

My MAF "tube" does not taper and the airbox internals look a little different as well

Steve