OTR VS Side intake?

[Bingo BIlly]

I have a VY SS and Im getting a Custom Tune and intake fitted.

I have read up on these intakes and some people say over the Radiator is better as less restirction to throttle body and sucks in cold air through grill.

Other school of thought is that over the radiator means more heat soak and the intake gets hot and cannot dissipate heat well. The side intakes in the respect are better.

I am going to get a maffless tune and some places say over the radiator whilst others are saying go for mafless pipe and upgraded airbox is better.

Can I ask the people who know on here to give an opininion from their own first hand experience. Which one produces more power/torque, which has better induction sound and which one suffers from heat soak.

Not too concerned of price as both end up costing similar.

[VX_INT]

The air in a OTR wont heat soak, will get sucked in to the engine before it even heat soak....

[Bingo BIlly]

is that universally accepted? That seems right under wot but cruising about town under light throttle would it suffer.

From my readings it seems the otr design makes more power.

[Wonky]

IMO the issue is not so much the heatsoak with an OTR but the location of the IAT (intake air temperature) sensor. This has been the subject of a fair bit of debate on here but as the VX INT said, the air coming through a well designed OTR will hardly be heated in the few milliseconds the air takes to pass through.

Various positions for the IAT sensor will allow it to read artificially high and pull timing, thus robbing power. A good OTR and well positioned IAT sensor will provide maximum power and induction roar!

[Bingo BIlly]

Im sold on the OTR. Im looking at the ORRSOM unit. Is that one of the better versions?

[SirNemesis]

The alloy or fibreglass version?

[Jman]

For what its worth,

On the question of induction sound alone, I had the 2nd hole mod done on my old VX SS which was of the old side type intake........AWESOME induction sound, really throaty. Best $35 bucks spent :rofl:

I have the ORRSOM OTR on the VE and can NOT notice any induction sound at all......mind you it would prob be difficult to tell over the exhaust note but honestly zero induction sound.

[sportwagon]

I had 3 dyno runs with my standard ve induction and each got slightly worse and used a g tech to test my 0 to 100 times and the same result each run slower than the last,then i got an otrcai and 5 dyno runs no difference and on the g tech my 0 to 100 runs almost all the same and my last run after 12 runs was my quickest time,that has me convinced.

[Wonky]

Im sold on the OTR. Im looking at the ORRSOM unit. Is that one of the better versions?

In pre VE I'm not sure but do know the DUS OTR works very well and looks awesome when colour coded to body - quite factory. My mate with red VX SS has red DUS OTR on it now and it looks great!! Went from 180rwkw stock with only catback to 240rwkw with VY2 HSV headers, Ballistic cats, Sureflo 3.5 catback, DUS OTR and tune. Still has more in it when tune tweaked as not pushed hard initially on dyno due to rebuilt diff.

[LuisS]

6 of 1 , 1/2 a dozen of the other.


As Wonky said , the position of the IAT sensor is very important - we had a car last week which had a "side intake" and was MAF tuned showing some weird IAT's , when I lifted the bonnet I found whoever had the pipe off last refitted the MAF sensor ( which also houses the IAT ) hard up against the top radiator hose !

I have a car at work at the moment on which I am about to do some back to back tests which should put the issue to rest.

[v8dude78]

6 of 1 , 1/2 a dozen of the other.


As Wonky said , the position of the IAT sensor is very important - we had a car last week which had a "side intake" and was MAF tuned showing some weird IAT's , when I lifted the bonnet I found whoever had the pipe off last refitted the MAF sensor ( which also houses the IAT ) hard up against the top radiator hose !

I have a car at work at the moment on which I am about to do some back to back tests which should put the issue to rest.

Should make for some interesting reading Luis out of curiosity the car in question is it VT-VZ or VE

[LuisS]

Hi Graeme, it's a VY with a big cam, higgins heads etc ;)

[Bingo BIlly]

it would be nice to see some pre and post dyno runs.

When i do mine I will definately advise. But the benefit will be difficult to conclude as Im getting tune as well.

[v8dude78]

Hi Graeme, it's a VY with a big cam, higgins heads
etc ;)
Sounds good mate some very nice work being done down there at the moment :goodjob:


it would be nice to see some pre and post dyno runs.

When i do mine I will definately advise. But the benefit will be difficult to conclude as Im getting tune as well.

I know with my set up (MCAI gts maf pipe K&N filter HM TRI-Y headers stock cats and 2.5 inch cat back) made a best of 188 RWKW at APS

Hopefully not to much longer and ill have the tune and cats done too

[smokey777]

For what its worth,

On the question of induction sound alone, I had the 2nd hole mod done on my old VX SS which was of the old side type intake........AWESOME induction sound, really throaty. Best $35 bucks spent :rofl:

I have the ORRSOM OTR on the VE and can NOT notice any induction sound at all......mind you it would prob be difficult to tell over the exhaust note but honestly zero induction sound.

totally agree lol i had a 3-4" tube going from air box to front of bumper on me VN & the induction roar was awsome lol but the OTR on me VY now VE hear nothing

[mikek73xu1]

Ill give an example of how similar the 2 setups can perform.
Over here in NZ we have 2 VX GTS's that are basically mechanically identical - both doing just over 300RWKW but mine is a pod filter on the std GTS pipe and the other has an OTR.
We have just done a standing and flying 1/4 mile event - mine went about a tenth quicker over the standing 1/4 and pulled about 1.5kph more over the flying 1/4 and i have the pod filter.
Now for me the interesting one is the flying 1/4 as this doesn't have the variance for example of who can launch the best - it was a run up of about 1km then into it - my average speed across the flying 1/4 was 244.5 kph and a time of 5.9 sec the other was 233 kph and 6.0 sec's so i reckon that shows the 2 systems work the same.
Mike

[ADAM 26]

For what its worth,

On the question of induction sound alone, I had the 2nd hole mod done on my old VX SS which was of the old side type intake........AWESOME induction sound, really throaty. Best $35 bucks spent :rofl:

I have the ORRSOM OTR on the VE and can NOT notice any induction sound at all......mind you it would prob be difficult to tell over the exhaust note but honestly zero induction sound.

i noticed this on my ve aswell, there was very little induction noise from the otr on my ve, but my vx and vy had lots of induction noise from there otr`s.

[OVZ-346]

i have a cammed vz ssz ute a4 with the normal bolt ons

as far as induction goes currently it has a mafless tune factory holden airbox with a 2 hole mod and mcai ebay plastic gts maf pipe it makes good power

i am fitting a vcm otr as a temporary trial to see if they really are that much better, possibly next week ,but it will not stay on the car as i personally rather the factory neat look of the factory setup

the car will have power runs and again be tuned to suit the above airbox setup then immediatly swapped for the otr and tuned to suit that

if anyone is interested in true , honest , unbiased back to back testing results on a cammed setup im happy to do it

im thinking once its tuned on each setup do 5 or so 3rd gear full power runs back to back and average the results on each setup to see a true power difference

but if im going to do it i dont want to be "abused" for lack of a better term because of the style of how it was done or anything like that because i have notning to gain from it either way. im really only doing it with my tuner to clear up some ideas we have..... although having said that its not rocket science , its been done a hundred times before

discuss :)

[OVZ-346]

i would LOVE to test other otr's if anyone around the Toowoomba QLD area has any but the vcm is the only one i have on hand for testing

[blow thru]

Sorry to dig up an old thread but what were the differences between otrs an maf pipe??