njmad

I have installed a skunk2 intake manifold on my 1997 acura integra gsr. and after about a week with it on there i wondered to myself if the intake manifold is allready port matched to the head. anybody know??

Thanks Nick

racebum

it isn't, in fact it's not even the correct port shape at all. the skunk2 im is a copy of the itr manifold right down to the b16 port shape. why was it not made to fit the gsr head? i really have no clue. if you're running this manifold on a stock ecu be sure to get an adjustable fuel pressure regulator and tune with a wideband or at a minimum the live date feed on a scan tool

njmad

oh crap really. i need a tune???

mouab18c1

iTrader: (5)

A tune for maximum power of the manifold. I did however drive with a skunk2 mani on my stock gsr and stock ecu for a year. Never had a problem

super jdm yo

the skunk2 manifold is a type r replica but they do make it for gsr's too. what it does is replicate the characteristics of the type r manifold. I have a pro series for my build and I matched it up to the head and it's reasonable but not perfect. you should be able to get away with not port matching it, it won't matter unless you're trying to make big numbers.

GagnarTheUnruly

iTrader: (3)

I've heard that they've redesigned it and that it now comes in at the right angle, but I'm not sure.

OH_1fstgsr

iTrader: (2)

The intake port angles are differnet on the GSR head vs the ITR/B16 head.
The orginal skunk IM for the GSR was basically a copy of the ITR manifold. So it would have and the incorrect runner angle.
The new Skunk Pro Series addressed this issue.
One thing to keep in mind is the Blox is a copy of the orginal Skunk not the Pro.

keepinitrehaal

I just bought a Pro series manifold for my build and this is good to know.

njmad

whats different about the b16 and itr head vs. gsr???

racebum

port shape. performance wise virtually zero

GagnarTheUnruly

iTrader: (3)

On B16/ITR the angle of the block where the IM mounts is slightly different, so the IM has to have a slightly different runner angle.

ITR is different from standard B16 because it has a mild hand port job on the intake side.

GS-R B18 heads have quench pads

Flow characteristics are ever so slightly different. Stock B16 may flow slightly better at high rpms and slightly worse at middle rpms. The difference is quite small.

Acuronda_SloTeg

you dont need a tune, you need a chip that deletes primary vtec. it needs to only run on secondary vtec. when you change the manifold from stock, you delete the butterflies from the system but the ecu doesnt know that and still tries to run off that, hence the common torque loss from the mani swap. the computer waits for the butterflies to open but they never do so when secondary vtec comes in it finally starts kicking once you get chipped for just computer programmed vtec it'll run great (this only applies to gsr's by the way)

OH_1fstgsr

iTrader: (2)

What! Primary and Secondary VTEC. This is the first I've heard of this. LOL.

Any of the tuning programs can handle the issue of the IAB's. It is a check box in the program very simple to address, on or off. A simple chip will not be good enough. A tune to adjust the fuel and timing to get back the torque loss can only be fully addressed with tune. The VTEC point will also be in a different location with the single runner vs the GSR manifold. Tuning will get you the best location of you new VTEC point.
A best guess will not get it done.

Acuronda_SloTeg

its simple lingo. people refer to it as primary and secondary, its just a change in the computer when the butterflies open (dubbed primary vtec) and the actual vtec controlled by the setup we all know (dubbed secondary vtec)

Acuronda_SloTeg

its the exact same reason why the car acts up if you take out the butterflies on the stock mani without chippin and reprogramming it. yes you are right it needs to be changed up, but if you mention that the stock mani is gone or butterflies removed, the company that you order from or go to will set the program right

GagnarTheUnruly

iTrader: (3)

Acuronda, that's bad information for several reasons.

First, even if you aren't confused about how the VTEC and IAB systems work, your nomenclature is.

VTEC = variable valve timing (and lift) electronic control -- it controls whether the valves in the engine respond to the primary or secondary lobes cast onto each cam. At low (< 4400 rpm) engine speeds and low throttle openings, VTEC keeps the valves operating off the lower profile primary cam lobes and above 4400 rpm it switches the valves to following the high profile secondary cam lobes.

IAB = intake air bypass system. On a GS-R dual-stage intake manifold, the IAB system switches a butterfly open in the intake manifold, that causes air to divert from a longer flow path to a shorter one. The longer, primary runner length lends more low end torque, and the shorter secondary length lends more high end torque. The IAB system switches from the primary to secondary runners at about 5700 rpm. This has NOTHING to do with the VTEC system.

Recap: In GS-Rs, VTEC switches the valves from following the primary to secondary cam lobes at 4400 rpm, and IAB switches the intake from long runner to short runner at 5700 rpm.

The reason there is a power loss at low ends when people disable IAB control is because the short runners are not suitable for generating low end power. This results in less air entering the combustion chamber and less powerful combustion. On a stock tune it also results in a richer condition, and tuning that condition can mitigate a small amount of power lost due to the inappropriate runner length.

Aftermarket ITR style intakes, however, do not flow like the GS-R intake at any engine speed. The SK2 intake with a good tune can outperform GS-R everywhere on the powerband. As a result, this intake will lean out the engine nearly everywhere in the powerband if the stock tune is kept. This lean condition is destructive and needs to be fixed with a tune. While it's possible to get better-than-GSR-tune basemaps from tuning specialists, those basemaps are best viewed as either band-aids for temporary use, or starting points for further tuning. No tuner worth his salt would ever recommend permanent use of a basemap.

njmad

can i just use a AME fuel pressure regulator for now with stock fuel rail and pump??

racebum

if you have a way to measure AF then yes, it won't be perfect but it can be safely driven

i was able to get part throttle af almost spot on with around 44psi when i did this for a friend. btw do NOT set it at 44psi and assume it's correct. get a wideband or at a very minimum a live data scan tool

njmad

do i need to get one with a gauge ??

illack91

good info ive been running my ls/vtec with skunk 2 mani on a stock gsr ecu for months now....i was thinking about going p28 on chrome.....how much power can be squeezed out

OH_1fstgsr

iTrader: (2)

I have owned my GSR for 11 years this month. This was the first time I have EVER heard of primary and secondary VTEC by anyone. Most people think the butterflies activation is the actual VTEC because they can feel and hear it.
I just found this to be quite funny.

When I changed my GSR from the stock OBD2 P72 ECU to a OBD1 P72 with a HONDATA S300 my tuner was able to find between 8-10whp throughout the entire power band.

njmad

thanks everbody. going to get a tune ssoooooon

racebum

spending 199 on a hondata s100 will make tuning easier. it's also cheaper nearly everywhere since hondata is so much easier to program. unless your tuner is really good with crome, hondata is usually the better choice

GagnarTheUnruly

iTrader: (3)

I'm going with Neptune RTP. It's also just a couple hundred more than Crome and a lot more versatile than s100.

bettsbanger

I've been waiting for this answer ^^^ for like 2 years. THANK YOU. I wanted to know what power the mani would make with s300. Proves to me that it's wellll worth the money.