On my TJ ive fitted the phenolic gaskets and a k&n panel filter and this has gone quite far to lower intake temps (35degrees after a 45min/28km run on a 20 degree day), i have plans to unrestrict the snorkel by adding a cold air pick up where the resonator was on earlier models

my question: is their any benefit/hindrance to upgrading the corrugated rubber intake hose between the AFM and TB to silicon hose and ali pipe/pvc pipe?

Well, in regards to adding a cold air pick up where the resonator is on earlier models... I've done that exact thing on my TF. I did mention it under a CAI thread (I'm sure) but nobody commented on it! It does work well though from what I can tell. Its not a replacement for the air coming in the front of the snorkel, just a supplement!

doing a custom intake looks good, on these cars, its about all there is too it. If you are going to do it, go for aluminum, while it gets hot like metals, it also cools exponentially faster. You wont be finding extra power but you might find a nice induction noise that wasnt there before.

Aluminium is the worst thing for air intakes & especially CAI, I don't know why people use it! Actually it completely defeats the purpose of CAI, and by the time the engine is warm (think summer:S) it would be making the intake temperature quite hot. Just try and get hold of some say, 55-60mm plastic tubing and run that down to the bumper from the snorkel resonator port. Vacuum cleaner hose works (cleaned of course). Since its an additional inlet and not the sole input, the corrugation makes no difference and you have the advantage its really flexible and quite easy to get hold of. If you were replacing the snorkel with CAI, then you'd have to go to a lot more hassle (but still, not using aluminium or metal).

The advantage with the snorkel mod is water won't be an issue, its a lot harder to suck up water through the pipe than to get air in through the front of the snorkel like normal!

like i said, since performance isnt going to be even measureable with a modded intake tract you might as well make something that looks nice. Other steels dont heat up as quick but stay hot for a lot longer then Al.

If i had the money it would be carbon fibre for all inlet tract including plenum and runners but its a magna, thats not going to prove out of sight with a modded intake...so Al it is.

Doesn"t really matter how quick/fast it heats up, not does it matter really what it's made off, just make sure it's flexable and is mounted well.

cheers guys got the answers i was looking for... think if staying stock after the AFM and doing the resonator CAI pipe install
probably gonna try wrapping it in exhaust bandage to see if it helps

the boss just splurged on a new scanner at work so i can record before and afters of the resulting temps

Some temps would be great as people seem to debate this endlessly. :)

If you thermowrap it, it would probably be okay, but that kind of defeats the purpose of using aluminium for looks in the first place. Aluminium does heat up and cool down quickly because it is an exceptional conductor of heat, the cooling down in this case is done by the air flowing through it (to the engine) as the engine bay heat remains the same. Actually using the aluminium job, the air would probably end up the same temperature as using an open pod, in which case the CAI is pointless.

The resonator and heat shielded piping (or plastic(type) tubing) isn't defeating the purpose though, it seems to work quite well. If you run a K&N panel filter and reduce the restictions in the snorkel then you could assume the performance benefit would be similar to that of having a K&N pod filter that is heat shielded. Just unfortunate Lukey don't make air filters for the Magna, I've heard they perform better than the K&N on Falcons & Commodores (and don't need oiling).

well i did a test on my intake temps with the intake stock except for the k&n and phenolic gaskets vs. a stock TH

the temps were consistantly lower at all times and were much quicker to drop when moving after sitting at idle for a while

went a bit further and fitted a vac guage to my intake to test restriction
with snorkel it measured 7PSI
without snorkel it measured 5PSI.... hardly worth writing home about

a 94 subaru imprezza is 50psi, an audi s4 is 32psi, an ef falcon is 16psi, and a prius is 4psi, and as a general rule anything 4 - 16 psi is excellent

i didnt have a chance to measure on the stock TH but next one i get in i certainly will... although id assume 12psi is fairly close

well i did a test on my intake temps with the intake stock except for the k&n and phenolic gaskets vs. a stock TH

the temps were consistantly lower at all times and were much quicker to drop when moving after sitting at idle for a while

went a bit further and fitted a vac guage to my intake to test restriction
with snorkel it measured 7PSI
without snorkel it measured 5PSI.... hardly worth writing home about

a 94 subaru imprezza is 50psi, an audi s4 is 32psi, an ef falcon is 16psi, and a prius is 4psi, and as a general rule anything 4 - 16 psi is excellent

i didnt have a chance to measure on the stock TH but next one i get in i certainly will... although id assume 12psi is fairly close

Never measured anything like these inlet restriction numbers before. Are you sure the scale was PSI? Seems more like inches of water. Where in the inlet tract did you insert the vac gauge?

Cheers,
Alan

WHOOPS!!! :iough:
what can i say... twas late

my vac guage reads inHg and the tech data i based it upon was InH20 from a magnehelic guage
which means that the post i just put up was erraneous
be it a faulty guage on my end (but all tests will assume otherwise) or on autospeeds end it appears that if i do the conversion inHg to inH2O the magna has 95inH20/68inH20 w/o snokel

but atleast i can try out my guage on some other cars to determine their readings

there is a ferrari next door at work :woot::woot::woot:
and a prius... and i gots a commode in the shop

so i will be back with my own data.... with more accuracy

Here was my setup, some might say overdone (110mm piping), but it worked well and had a repeatable noticeable improvement over stock when switching back and forth between this and the stock setup. Only downside of this was an increase in dust collecting in the airbox, but it wasn't a problem I just added cleaning out the airbox to my general maintenance of checking fluids weekly.


http://img151.imageshack.us/img151/3655/dsc00021yyx.jpg

I'd been wondering about the benefits/legalities of doin something along the lines of Subaru kinda style mod for cai and was wondering this... would it work modding the filter box to rotate it 90 degrees clockwise and actually have a vent in the bonnet so when the bonnet's closed, it seals/butts to box and eliminates restrictive snorkel altogether and possibly helps with "forcing" air intake in the process... any ideas?

Cold air is both good and bad. Depends where you want the benefit and what sort of fuel/injectors/direct or port injection etc.

For economy in cold weather and small throttle openings a bit of heat in the inlet air can help fuel atomisation. This helps fuel/air homogenisation, so a better burn and less emissions. However with direct injection very high fuel pressure is used so hot air won't help atomisation. Same with multi hole injectors like on the 380. Hot air probably won't help them either.

For power cold is always better. Cold air is more dense so you can fit more oxygen in the same volume. This means more fuel can be added, so the engine works like it has slightly bigger cylinders.

There are other benefits too if you can remap the ECU. Cold air cools the piston so you can lean out the full throttle mixture from the typical 11:1 - 11.5:1 to something closer to 12.7:1 without harming the pistons. (Direct injection cools the piston too, thats why they can run higher compression and leaner mixtures). Race engines go as lean as 13:1 - 13.2:1, depending on what gives best HP, because they only hold full throttle for maybe 15 secs. Manufacturers have to test and tune for the worst case scenario, perhaps pulling a big load up a long hill at 40 deg C into a 100kph headwind with the air con flat out and water temp at 120 deg, holding full throttle for minutes. A lot tougher than what is faced by a race engine!

As well as leaner the engine may benefit from a bit more spark adv, particularly if like the Magna its only 9:1 comp ratio. With hot air you can't do that, but with colder air you can add adv.

With our engines mounted sideways there is a lot of heat buildup in the valley, and the cosmetic bits just serve to hold more heat. I had a look at what Graham has done on his car but I suspect he will only get the full benefit when he remaps the ECU. He has a heat shield in the valley to limit heat radiation into the lower manifold and a flex pipe to blow cold air through the area. That moves any hot air and cools the fuel rail. For best HP you want the fuel cold so that when evaporating it pulls down inlet air temp as much as possible. If the rail is hot it keeps putting heat into the fuel and what returns to the tank raises the overall fuel temp.

Cheers,
Alan

Sounds great, i think we'll see a few copies that shortly!

a flex pipe to blow cold air through the area. That moves any hot air and cools the fuel rail. For best HP you want the fuel cold so that when evaporating it pulls down inlet air temp as much as possible.
Cheers,
Alan

Would a flex pipe feeding air to that area be a worthwhile mod even without the heatshield?

Alan would this sort of piping be good to use?

LINK (http://www.doityourself.com/invt/6753552)

I would have assumed it would be necessary for the heat shield to be secured or bolted in place to stop movement or any rattle noise. What about covering the heat shield with a "heat shield cloth" or similar? Like they to for turbo applications.

For the plastic duct, wouldn't a flexible metal tube be better? I would have thought the plastic one may melt under certain circumstances, or be a fire hazard.

This idea has crossed my mind in the past, I'm glad someone has decided to move forward with it.

Would a flex pipe feeding air to that area be a worthwhile mod even without the heatshield?

Alan would this sort of piping be good to use?

LINK (http://www.doityourself.com/invt/6753552)

Yes just the pipe would work OK. Not sure what pipe he used. From memory it looked 60-65mm dia.



I would have assumed it would be necessary for the heat shield to be secured or bolted in place to stop movement or any rattle noise. What about covering the heat shield with a "heat shield cloth" or similar? Like they to for turbo applications.

For the plastic duct, wouldn't a flexible metal tube be better? I would have thought the plastic one may melt under certain circumstances, or be a fire hazard.

This idea has crossed my mind in the past, I'm glad someone has decided to move forward with it.

Don't think any fire problems. All the other plastics on the engine would go up in smoke too, and the pipe isn't near the exhaust.

The shield will wedge in under the heads OK. Graham didn't use any screws/bolts. Covering helps if the shield has a big contact patch with something hot, but if the contact area is small and there is a good air gap and some air flow coverings don't make much difference to heat transfer past the shield.

Cheers,
Alan