OTR maffless VS ss induction growler

[Gunzero]

just want to know whats better and cheaper for my clubsport over the rad and a maffless tune or the SS Induction growler kit some rough prices would be good to

[Munz]

Better = Dus/VCM otr + mafless
Cheap = Mace Airbox + maf tune still get good power from this setup

[CRUSTIN]

Your talking about 10kw vs 12kw gain with tune. And that difference is at speed, at slow speeds the otr does nothing.

[Sabbath']

Your talking about 10kw vs 12kw gain with tune. And that difference is at speed, at slow speeds the otr does nothing.

Go MAFless and OTR.

You will pick up bucket loads of torque, along with the power gains.

[CRUSTIN]

The tune yes, Otr has little effect on performance. People get them cause they are cheap and look good.

[Sabbath']

The tune yes, Otr has little effect on performance. People get them cause they are cheap and look good.

Bullshit. Straight induction path, lower intake temps.

OTR v Standard Airbox sees almost 40 degrees difference in IAT. now explain to me how unrestricted airflow and lower IAT's provide little effect on performance

[GRPABT1]

This topic is old as the hills, SS Inductions intake have been proven to suck balls many a time. The OTR has also been proven to work at the track.

[Surfwagon]

Dus OTR and mafless tune FTW.

[Phillshz]

Bullshit. Straight induction path, lower intake temps.

OTR v Standard Airbox sees almost 40 degrees difference in IAT. now explain to me how unrestricted airflow and lower IAT's provide little effect on performance

After seeing this repeatly thrown around in various threads and forums curiousty got the better of me so i carried out a IAT test on my VZ l76 auto.

I have fitted a k & n filter,MCAI shroud and modified it with the 2 hole mod,it`s a stock car otherwise.
Using a trade quality digital multimeter and a wire temp probe with a accuracy of 2.5 deg c over -50 to 250 deg c range (means it pretty good and accurate).

Behind headlight in the little shrouded area. Temp is ambient at idle and on the move. (fans or a/c on see`s it climb to double ambient)

Inside intake tube into air box under filter. Temp is 2-3 deg higher than ambient but drops to ambient on the move.(Fans or a/c on see it gradually climb but not like behind the light)

Before MAF in intake pipe (taken at hot idle and at 2000rpm). Temp is 4 deg higher than ambient at idle,2-3 deg higher than ambient at 2k. (fans on see`s the temp climb to 12 deg above ambient but fans off see`s it drop back to 4 above ambient at 2k)

Right in front of T/B in intake pipe. Cold start and a 30 min drive in stop/start 0-80-0km/h traffic. Temp is ambient for some time then begins a slow climb (nearly 10 mins before it climbs,tells me radiator/underbonnet heat is starting to affect temps). Once engine is hot temp flucuates from 6 to 8 deg above ambient whilst at hot idle(no fans,fans on easily sees double ambient but fans off at 2k sees a descent back to 6-8 deg above ambient then at hot idle a rise to 10 deg above ambient and stays constant).
On the move though temp sits between 3-4 deg above ambient with hot engine at a constant 60-80km/h (anything above walking pace sees the temps start to drop).

I`d like to check it on long trip to be certain but it does seem the stock intake (or at least the MCAI/2 hole version on any VZ V8,which is prob the ultimate in stock intakes due to it`s 90mm size and design) does cope well with heatsoak. Remember the air is passing through the intake at a high speed so it doesn`t get much time to absorb much heat.

I did read somewhere that a mild (tune/full zorst) monaro had a stock intake setup and was at WSID doing decent times,then fitted a OTR and had the tune tickled to suit just to see how much it improved times, it then ran .2 and 2mph faster. I also then read somewhere else that a OTR is good for 5-10rwkw over the MCAI (this was from a tuner), while the MCAI is said to be good for 5-10rwkw over a dead stock intake.

Take from it what you will. But i believe the basic thoery behind a OTR dominance is for the vt-vy`s with the MAF as the known restriction,the easiest way around it was to bin the entrie stock intake and go MAFLESS OTR with a tune to run MAFLESS. The tuning guys found a profitable and in demand market and had the results to back it up,which is why it still works today. The big 90mm 6.0-6.3L intakes now make a OTR optional not mandatory these days,there are some good looking ones out there and they do look the business over a stock setup.

Cheers Phill

[GRPABT1]

Nice post Phil! Some good points there with evidence to back it up. Personally I would go straight for the best if forking out the dollars on an aftermarket intake and go a big filter OTR. But you points regarding the later models with larger intake and maf do make sense if budget does not extend to the price of aftermarket intake and tuning.

[Sabbath']

Take from it what you will. But i believe the basic thoery behind a OTR dominance is for the vt-vy`s with the MAF as the known restriction,the easiest way around it was to bin the entrie stock intake and go MAFLESS OTR with a tune to run MAFLESS. The tuning guys found a profitable and in demand market and had the results to back it up,which is why it still works today. The big 90mm 6.0-6.3L intakes now make a OTR optional not mandatory these days,there are some good looking ones out there and they do look the business over a stock setup.

Cheers Phill

Nice investigation. It's a shame that it doesnt encompass the temperature that the IAT sensor actually picks up from being on the airbox to being on an OTR. Im aware i didnt write sensor in my post, but i was on my phone and it was early so i apologise.

[CRUSTIN]

Bullshit. Straight induction path, lower intake temps.

OTR v Standard Airbox sees almost 40 degrees difference in IAT. now explain to me how unrestricted airflow and lower IAT's provide little effect on performance

Dont be a child sabbath, listen to what im saying.

If i took my intake pipe straight off the throttle body there would be no restriction, does that mean i would feel any power gain? No, the intake pipe is more than large enough to give unrestricted flow, that is of course if you remove any bends with a pod filter. Your intake is a restriction only after your have increased maximum flow because every manufaturer matches engine output to parts.

And for temperature, insulating your pipe with foil would give the same result. And most of the temperature is from your manifolds, have your got manifold insulators?

An OTR will give most gains on track and high speed, it will do nothing for a dyno or around town.

I also have a mate who is a car mechanic and ownes a drag car, he tested an ss with standard intake vs growler, he lost power. And dont go on about ambient temps and whatnot, if your gains are less than environmental variences, it isnt worth it.