Does the skunk2 manifold really make a difference?
Does the gsr skunk 2 manifold fit a Type R head also?

 

yes and no

the manifold is an improvement over the gsr but requires a change in fuel pressure at a minimum to run correctly. to get it perfect you'll need a tuneable ecu in order to add timing in the mid to lower rpm range where it will need it vs the gsr manifold

the edelbrock performer x is still a better manifold

the gsr and b16/itr heads are not interchangeable on the intake side but are on the exhaust.

 

if the head is not port matched, it's pretty much pointless. it will just be a bottleneck

 

not really, port matching decreases turbulence but does not increase cfm

 

on my GS-r integra, i bought a S2 Pro series manifold, just did the bolt on swap.. no tuning, no adjustments.. nothing.. just through a Hondata thermal IM gasket on while at it (not recommended, they suck *** and blow after a few months) and then installed a Prothane Polyurethane insert in the rear mount since the IM was out. Anyways i went from running a very consistent 15.6 @ 93 mph to a 15.1 @ 96 mph just by doing the manifold swap. Also as stated above, the type r and gs-r are not compatible, i know this because i bought the type r and tried it because i was a honda newb and the supposedly honda guru around here told me it would fit.

 

cfm? please, enlighten

 

On a completely stock gsr motor, ie stock compressionn, stock head, it will actually hurt you in performance. It decreases the mid range torque of the motor by disabling the butterflies.

In order to get the best out of it, you will need an obd1 ecu, such as a p28 or you can opt for a p73 obd2b ecu if you wish to stay obd2. You basically need an ECU that does not have the butterfly function.

Even with just an obd1 ecu, you will not see the performance gains you are looking for without the bump up in fuel/timing. It all really depends on what your power goals are, and your budget as well.

 

not true, it actually will make the car faster even untuned. not exactly sure why but i have tested the theory on a stock gsr.

the whole torque argument is one that makes sense on paper but doesn't carry through to the real world. an itr for example has more torque than the gsr everywhere.

a stock p72 ecu will feel a bit boggy under vtec though, a little less fuel and a little more timing generally fixes that.

 

there's no question here. ask one and i'll respond to it. port matching is often not a large performance gain, it's just a small part of the big picture. on a stock gsr the intake manifold is probably the biggest restriction, after that it's the intake bowls, beyond this i would either have to find someone who has or use a flow bench to test where the most significant changes happen. usually if i put a head together it's either stock or completely ported. what my goal is with the engine dictates which. that and how much time i want to spend on it. to port a vtec head and actually make it pick up a decent amount of flow it would take me 8-10hrs, closer to 12 if i get **** about details. this is also why having your head ported by hand costs cash, you figure $50hr@12hrs=$600

 

Yes, what i meant is that it will pick up more peak power over a stock gsr manifold, however, it will lose some drivability at lower rpms. The vtec point, which is set at 4400rpms on a gsr, would not be beneficial in the powerband that a single runner intake manifold such as the skunk2 or ITR would provide. This said using a p72 of course.
Wouldnt this type of setup require you to change the vtec point in order to get the best powerband?

 

haven't tested it to find out, if i had to guess vtec would benefit going to 5000 or so. if it would be faster? who knows, it would be easier to drive around town though. the low cross over of the gsr i honestly don't like for daily driving.

 

I never liked it to begin with either.

I too was in the predicament that the OP is in. After i built my motor, i decided to go ahead and get the Skunk2 Pro Series manifold, and it really brought everything to life. But then again, this was after the cams, valves, valve springs, sleeves, pistons, rods, ECU, fuel pump, injectors, etc. It was pretty much the last thing i did.

The ECU was tuned, the vtec point was raised to about 5200 or so. And thats when i noticed the car was using the powerband to its full potential.

 

forgive me for my lack of knowledge on the terminology. i was just curious what was meant by the term "cfm"

 

it stands for cubic feet per minute. it's used as a measurement of airflow. if you look at the power producing part of an engine you have from the throttle body to combustion chamber. the amount of air that flows through there with normal atmospheric pressure is measurable. porting heads and different manifolds can effect this, sometimes not always for the best. the overall goal with a motor is to increase flow without a decrease in velocity. velocity is just as important or honda would use runners the size of your fist. huge runners can flow **** tons of air but would have no velocity with such a small 1.8L bottom end. back to you and port matching. this can be effective in preventing turbulence but as you should be able to guess by now, it won't increase airflow overall unless that very spot is the biggest bottleneck on the intake side. as a rule intake ports themselves almost never are. the bowl is one of the biggest since that's where the air makes a very sharp turn and goes past the valve into the chamber. optimizing the bowl/valve/seat/chamber area by itself is worth a few hp on a b18c

 

good stuff. thanks for going into such detail. appreciate that
but wouldn't the turbulence of a mismatched plenum to port cause poor flow?

 

could yes, however the intake ports on a skunk2 IM are already the wrong shape for a gsr head. they have b16 ports and the gsr head has, well, gsr ports. totally different. from first glance the gsr appears to have a superior intake runner but the flow bench says they are basically the same. what you ideally want is either an exact match or the intake to be slightly smaller than the intake runner in the head. if the intake manifold runner ports are larger than that of the cylinder head then yes you run air right into an aluminum wall. not at all good for flow. if you ever hear of someone porting their IM and loosing HP there is a good chance this is the reason. the s2 manifold or better edelbrock performer x haven't been produced with a larger opening than the head. if they had been then the port matching could be a big deal. since they aren't the port matching only would benefit you if it was the bottleneck in the system.

this also should paint a picture of exactly how a turbo works in your head. if motor X can flow 280cfm per cylinder, what does that jump to at 20psi? exactly, now add enough fuel to have a powerful A/F ratio and you just moved a lot more air through that cylinder. add in displacement and rpm and you have a formula for HP. when you get a solid grasp on the 4 cylinder engine it will seem more like math than the art of building you feel when we first get into cars.

 

great info

 

And why do you prefer the PerformerX over the Skunk2?

Do you know if there are differences between the Skunk2 and the OEM B18C TypeR Intake manifold?

 

from my understanding, the skunk2 is a replica of the b18c5 mani. but with a c1 flange to fit gsr.

 

not an exact replica just based on the design

 

Just installed a S2 Pro IM on my bro's GSR EK hatch and it seems to pull harder than before and there's no CEL or Bogging whatsoever and he's running the JDM OBD2A P72 ECU. He's got the blue Hondata IM gasket as well and we slapped it on w/o the extended studs. After researching that it needs extended studs, we'll have to change the Hondata gasket out for a Honda OEM one since the studs are too short.

 

Ok, it bases on the B18C5 OEM intake manifold. But is it improved so that it makes sense to swap it against an OEM IM?

Differences to the performer X ? Maybe back to back test?

 

I'm going to have to disagree, only because i swapped out my stock GSR manifold for a new one, with out the butterfly's and it ran like Poop. didn't want to idle or anything.

But thanks to Dave at TPR for tuning it.

 

My opinion is
The Skunk2 IM isn't much better then stock when it comes N/A
And honestly it i feel there not much use for it until you go FI
not saying it's true but it's how i feel about it.