i know there's probably threads about porting and polishing a GSR intake manifold, but i don't think i'd have much luck getting my question answered if i searched. my question is:

if i had my stock GSR intake manifold ported and polished, and had my head port-matched to the intake manifold, is it possible that it will flow more air than a skunk2 manifold? i'd like to get some quotes or figures of how many cfm's the skunk2 flows compared to someone's p&p GSR IM. i know not all p&p jobs are the same, so it will be hard to compare. but if someone has had their stock GSR intake manifold professionally ported and polished and had the head port-matched, i'd like to hear how it flows compared to a skunk2 manifold and if it was tested to see how much air it flows. also, how much green did it run you? dyno plots?

**EDIT: also, is it possible to port the IM out enough to need a 65mm throttle body? if not, a 62mm will have to do i suppose.**

thanks.

 

well im in the process of port matching mine right now and doing a little port and polishing also. Well heres the deal from what ive researched...the angle of the gsr head is different than the b16 and itr, its not as steep or steeper, cant remember but i think its less steep. anyways, the skunk 2 im was designed originally after the itr im so it has the steep angle which is undesireable for the gsr head, also the injector angles are different, i saw a dyno plot and i cant remember where, but if you search you can find it, well the gsr im actually gained more hp and tq in most of the graph than the sk2, you can get a realllly custom gsr im from a couple builders out there if you send yours to them, its gonna cost you but it will kill the numbers a sk2 put out and its no where near the same as it was when you sent it to them, they do all kinds of crazy stuff in there, RLZ does it, in my opinion if you dont want to spend that kind of money i would just do a little port matching yourself and stick with the gsr im, i have two of them, one of them i took the butterflies out and am going to weld up the holes and get it as p&p'd as i can without a bunch of special tools, im gonna try and get a plot from my stock im and the one im working on, so stay tuned and look for the post when i do it

 

sweet man. this is the kind of info i was looking for. i'll def keep my eye out for your dyno plots when you get everything done. if you get it done sometime soon, maybe you can post up on this thread.

so you're doing the port matching and polishing yourself huh? what kind of tools are you using? a dremel? anything else? i love the difference in sound right as the butterflies open on the GSR intake manifold. i'd like to keep the butterflies in, but i know the real power comes from them being removed also. if only there was a happy medium.

**EDIT: nevermind about my questions, i talked to you on AIM**


Modified by Train at 10:19 PM 5/31/2004

 

yeah the happy medium is the problem, im gonna try the manifold with the butterflies in and the p&p and then with no butterlfies and the plate welded up and see what performs the best, ill keep you posted

 

sweet.

 

does anyone else have any input?

 

NOT WORTH IT. THE MONEY YOUR SPENDING ON THE P&P YOU COULD JUST BUY A SKUNK 2 MANIFOLD. PLUS YOU CA N GET THE BIGGER THROTLE BODY.

 

go look at some dyno graphs of a skunk2 over a gsr im on the same motor, skunk2 doesnt make power in some places over the gsr im, and where it does make power its not enough to really matter, so i would have to say that the skunk2 is not worth it, but whatever floats your boat

 

if erik aguilar has the fastest honda in the world and uses the stock GSR im, thats gotta be sayin somethin. not that his intake manifold hasn't been extremely worked over, but if the skunk2, ITR, or JG, or whatever other intake manifold put out better numbers than he got with his P72 im, he'd be using that. and i know erik has his runners and head ported out a crazy amount and the shape of his ports are square (he worked around the water jackets), but i believe there is a lot of potential in the GSR im and i'd like to see what kind of numbers i can get out of it.

 

so how would u utilize a larger throttle body, bore the IM out to match a larger throttle body i assume?

 

yeah you just gotta port match it so it flows smoothly into the plenum, not a hard task to do, if you do it just take your time

 

IMO, i can feel a difference. i got my mani. p&p. first thing that i noticed is that response picked up. i got my mani. port matched to my p&p head and my itr throttle body. second thing i noticed is that when vtec engaged, it was louder.

all in all, i think it was a good thing to do to my car/setup. hope this helps out some.

 

did you take your butterflies out, leave them open, or leave them stock...

 

i left them in (stock).

 

so how much does it cost to do all that, if u could break it down, like p&p the im, and the head?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by one_c18b &raquo;</TD></TR><TR><TD CLASS="quote">IMO, i can feel a difference. i got my mani. p&p. first thing that i noticed is that response picked up. i got my mani. port matched to my p&p head and my itr throttle body. second thing i noticed is that when vtec engaged, it was louder.

all in all, i think it was a good thing to do to my car/setup. hope this helps out some. </TD></TR></TABLE>

yeah, i'd also like to know how much you spent on the p&p job for the im. did you get the p&p done, then do the port matching at a seperate time, or at the same time? either way, how much did it cost to do all that?

 

generally if you get someone to do it other than yourself they will do the port matching at the same time as the port and polishing, if you are doing it yourself, the easiest thing would be to do the portmatching first, bc youre taking off so much material that the finish on the alum will be rougher than you want it , so you can then port and polish everything and get it nice and even, there is this place that does porting and polishing of intake manifolds, ill try and find the link to thier website and post it, im just doing it myself to save the 100 bucks or whatever it cost

 

OK, finally got mine done, other than getting the old manifold out and some vacuum line problems, everything went very smoothly. I will say this....BIG difference was noticed, just from driving down the road once, so im going to the dyno this week, and ill be posting some numbers up...so check back

 

sweet man. got any pics of the manifold all taken apart? any inside shots? i'd def check back to see some dyno figures.

 

nah, i didnt have the chance, i wanted to get it running to see if it was going to do anything, after i dyno on wednesday i have to take it off to get the head worked on, hit me up on aim and ill show you some pics maybe

 

Not meaning to jack this thread, but I have a '99 GSR intake manifold for sale. PM me an offer.

 

I got a skunk2 honed out and p&p, the throttle body port match for my jg throttle bodie. Done by endyn, he benched flowed the the intake manifold and said that it out flowed individual throttle bodies with a gsr head. http://www.theoldone.com