Air feed from front to rear - and Viz Paint ?

Daz made an out of thread comment in another post - so I raise a new thread.

Quote
I can let you know how you get air from the front to the rear,
Remove the rad from the front of the car,remove the boot lining.rad is placed into the boot,the rear boot needs venting and scoops placed on the rear boot to force air.
the tunnel where the coolant pipes where is now an air induction channel.
moving the rad is very easy,if you remove the boot floor as well.the engine performs better and cooling issues are sorted out.
End Quote

I shan't be doing this mod any time soon Daz! That's one heck of a modification. Has it been done before? I realised you were thinking of relocating the radiator to avoid the long coolant run - and now understand how you would have used the old radiator space as an air intake. Thanks for the info - it's a cunning idea.

My MGF ownership is all about enhanced driving enjoyment rather than conversion to a race car. Else I'd have bought something else in the first place. For me, it's a lot of fun getting various aspects of the car that are "not quite right" to "just right" however long it takes me. Air intake is next on my list.

I love the induction roar from my K&N flower pot, but the air tubes hang under the car, facing forward. It's a cheapo method that's always getting bashed on sleeping policemen. The tubes also have the potential to carry water and transfer road grit into the engine bay - and why I've mounted them 4" distant from the filter cone. The method probably pays lip service to "cold air feed" and a sealed air cone with airtube to the gearbox side vent seems the most obvious solution to these "issues" - as used by others. However, I have heard that external airflow at that grill point could be sucking air out rather than encouraging it in.

Another job for viz paint perhaps to check what really happens down there. I wonder what materials to use that won't permanently hurt my lovely paintwork?

This site is quite interesting http://f1-dictionary.110mb.com/flow_visualization_paint.html

Jeff

You could use emulsion paint that would just wash off. Unkess you left it for some time.


Talking about air flow I was surprised that when my engine bay fan operates it blows air out of the o/s side vent. I assumed it would suck colder air in.:shrug:

Pilot error, David.
Suggest to put a piece of toilet paper or a pound note to the mesh when the fan is running.

I'd bet it will stick on due to the air suction :whistle:

Btw. I'm on the MGF matter now since more than 12 years and follow the air flow discussions for the same time.
My question is to you other skilled engineers out there:
Did any of you ever look up or calculate yourself about the amount of air flow and speed required to pull down the temperature of a 100kg aluminum block from lets say 100° C to 99° C ?
Would recommend
You'll wonder and leave out such games with air flow to the engine bay

However, it may look good at our little car :lol:
:coat:

Dieter wrote: Pilot error, David.
Suggest to put a piece of toilet paper or a pound note to the mesh when the fan is running.

Well been throwing pound notes at the TF for some time now - maybe its time to try toilet paper :bust:

Hi jeff we have built three track cars with front to rear air and rear mounted rad.cars didnt have heaters.But we do know how to get air better into the engine on a road car.A good friend of mine works for a woking based f1 company.the ns air take,external scoop,built a solid pipe direct to manifold via a filter.air from the bottom isnt a good idea.as you know.
we know how to do it but not how to build the air intake.

to keep the engine cooler,we have built a few race mgfs.the summer months are the worst for the mgf,like racing.we used to make holes in the inspection cover and no carpet,but for a road car that isnt any good,but removing the foam underneath the inspection cover carpet helps believe it or not.
Another thing is move the engine bay sensor nearer the engine,the fan comes on sooner.

Dieter wrote: Pilot error, David.
Suggest to put a piece of toilet paper or a pound note to the mesh when the fan is running.

I'd bet it will stick on due to the air suction :whistle:

Btw. I'm on the MGF matter now since more than 12 years and follow the air flow discussions for the same time.
My question is to you other skilled engineers out there:
Did any of you ever look up or calculate yourself about the amount of air flow and speed required to pull down the temperature of a 100kg aluminum block from lets say 100° C to 99° C ?
Would recommend
You'll wonder and leave out such games with air flow to the engine bay

However, it may look good at our little car :lol:
:coat:

Definitely blowing Dieter, I have witnesses! Maybe my fan is wired wrong.

dazlightyear wrote: to keep the engine cooler,we have built a few race mgfs.the summer months are the worst for the mgf,like racing.we used to make holes in the inspection cover and no carpet,but for a road car that isnt any good,but removing the foam underneath the inspection cover carpet helps believe it or not.
Another thing is move the engine bay sensor nearer the engine,the fan comes on sooner.

Relocating the ambient air sensor is a very good idea. I find it only ever activates the engine fan after a thrashing and when coming to a standstill. It soon turns itself off. I'll experiment next time I've got the tool box out!
Agree with Dieter that this fan sucks in air to the engine - I last checked with a sheet of photo copier paper (could find a pound note at the time). Frankly, I can't see the problem with it working 100% of the time, once the engine has warmed to just under half way on the gauge. The noise might get on one's nerves though, if it's not really necessary to be operating.

Cooling the engine bay air is not my primary concern. I am as happy as I can be with the engine cooling on my MGF since opening out the waterways in the head and fitting a PRT. I have good condition rubber hoses, rust free bypass pipes, new water pump and stainless under floor pipes. There are twin fans on the radiator. Although to enhance my confidence level, I might fit an ally radiator when I get the chance.

What I really want is colder air feed for induction. I believe cooler air has a higher oxygen content and is more dense than air heated in the engine bay. Cooler air aids efficient combustion = more mpg or more power (whatever way you care to look at it). In winter months though, cold moving air might iceup the throttle body - has that been a problem for anyone? It used to be on some of my old motorbikes!

Jeff

I have a Mk1 F, which had a ludicrously convoluted air intake and a 48mm throttle body.

I upgraded to a 52mm alloy throttle body, fitted a Pipercross Viper and took air from NS vent, as I didn't want to go the under car route, as I was worried about standing wate/debris etc.

The larger throttle body coupled with larger intake increases the volume of air and using the NS vent ensures cooler, denser, air - so both improve the breathing of the engine.

There are loads of bits on the net discussing the pressure at the vent and it seems that it's fairly neutral. Someone also pointed out that, as a car's aerodynamics are meant to keep the car on the road, then under the car would be an area of NEGATIVE pressure and therefore not a good place for an intake.

Anyway the change made a marked difference to performance, increased the MPG and the water temp gaugue read a notch lower than before the work.

No problems were encountered with icing up last winter.

Check out the 'how to' section to see what I did and a fuller explanation.

BTW, if you have a Mk1 the biggest problem is getting the resonator box out

hi jeff can i have two of your bottom mounts and i will put them on my car and our sales car

dazlightyear wrote: hi jeff can i have two of your bottom mounts and i will put them on my car and our sales car

Okay Daz I'll do a couple for you as well.

Jeff

i think I have 2 mounts and I can get a number really cheap for you,you could start a whole new company making bottom end mounts.