OH_1fstgsr

iTrader: (2)

***PICTURES OF NEW MANIFOLD ON PAGE 6***
https://honda-tech.com/forums/showth...2808750&page=6

***PICTURES OF THE CUSTOM CAI 3.5" TO 3" ON PAGE 8***
https://honda-tech.com/forums/showth...6#post47588506

Many of you will immediately say no way just from the title but first look over my proposal.

As some of you already know when I installed the Px on my GSR it only made 3whp more and lost 20wtq, then with an additional retune it ended up at 6whp increase and only a 10tq loss.
Here is the link if anyone needs a refresher. https://honda-tech.com/forums/all-motor-naturally-aspirated-44/disappointing-results-performer-x-huge-torque-loss-minimal-hp-gain-2776313/

Basic I want to get my torque curve back and see if I can gain 6whp up top.
The 1st changes will be to the plenum section of the manifold. I am thinking of removing the shaded area. This will allow the following.
-Air can now come straight into the plenum and not hit the first divider 2nd pic.
-It will now have a larger plenum volume, this should help top end.
-The runner length will be shortened with the material removed. Less runner surface area, more air speed.



These change do however create an area of difficulty. The butterfly plate would now have poor entrances to the runners, no taper. Some machine and/or grinding will be needed to address this issue. The outline of the cut space of the plenum section is shown in red.


The next item is the butterfly plate. Basically the butterfly section will now look like my throttle body. Bolts replace and the shaft machined to reduce the cross sectional area. Also each plate with be knife edged and don't foget port matching to the runner section.




I am looking for pro’s and con’s to these ideas ONLY and support relating to improvement of this manifold to see if I can out do the Px in my application.

Here is a the dyno graph I am trying to improve.
RED is new tune with the Performer X.
BLUE is old tune with GSR Manifold.

OH_1fstgsr

iTrader: (2)

Old set-up
PnP'd GSR intake manifold
AEM GSR CAI

New Set-up
Performer X IM, port matched
AEM ITR 3" CAI
BPI 3" Velocity Stack

Everything else the same, listed below.

Exhaust
SMSP 4-2-1 2-1/2” Header
SMSP High Flow Cat 2-1/2” 300 cell
PTM 2-1/2” Custom Exhaust w/Vibrant Muffler

Intake
RC Engineering Ported GSR Throttle Body 70mm>64mm
RC Engineering Fuel Injectors w/clips 370cc

Block
USDM ITR Pistons (81.25)
USDM ITR Rods
(Compression Ratio ~11.6:1)

Head
DPR Stage 5 Port ‘n’ Polish
ITR Valves, ITR Springs, ITR Retainers, ITR LMA’s
CTR Intake Cam Shaft
ITR Exhaust Cam Shaft

ECU
Skunk2 OBD2a>OBD1 Harness with IAB control
P72 OBD1 ECU
Hondata S300
__________________

raverx3m

iTrader: (1)

i belive its been tested by many shops already, after many hours of grinding the gains were not that big.
you will need a flowbentch to see where its all going,
i tried to do that as well, and emailed endyn.
they have done tests with gsr IM
and concluded that you can get same gains in midrange with a ported aftermarket single runner IM and keep the top end power.

raverx3m

iTrader: (1)

well i checked the dyno, and the guy in the first post mentioned bigger cams.
as well as endyn also told me that theres a limit to how far you can push the gsr IM beyond that it just dont have enough air flow.
but if you using stok engine gsr i think would be better.
isnt the performer x meant to produce power at higher RPM?


i even went as far as trying to get my hands on k series dual runner IM to see if it can be modified to fit b series lol. but couldnt find any

BigBlock22

remember the first 9 sec NA Honda that was built by Erick Aguilar? it used a modified GSR manifold. that alone should be enough proof to say there are great things to be done with the GSR manifold. it all depends on whos doing the work on the manifold. i think there is room for more work/improvement. if the money is there bro, i would send it out to Ericks Racing to see what they can do

jmart41791

dang that makes you wonder if honda really knew what these things are capable of lol

raverx3m

iTrader: (1)

everyone says that,
but does anyone actually know what has been done to it?
it might have been completely gutted and rewelded.
endyn did just that, they did alot of welding and cutting.
remember also that the 9 second car was idling at 3-4k rpm or something like that?

OH_1fstgsr

iTrader: (2)

My GSR manifold has already been basically polished and a bit of some porting. Most of the work has been done in the runner section. The butterfly valves had no change and I made very nice increases in the mid range with the old set-up. I am now looking to improve the top end and maintain the midrange.
The first thing I notice while study other manifold designs was the following on this cross-sectional image of a Skunk2 manifold the air can come right in from the TB opening with out any interference. The GSR does not have this type of design. The picture above shows this interference. I am expecting a reduction in the induced turbulence as the air enters the plenum. Calmer air is happier air. In the pic above you can see a bit of oil on the wall of first runner. That is the only place that had oil, a low pressure area due to the design, maybe?

raverx3m

iTrader: (1)

well unless you can make one big butterfly instead of 4 little ones and reshape it after the butterflies.

00Red_SiR

I think it's very interesting what you're doing. I believe that if you cut that section out of your manifold you'll end up losing a good chunk of that juicy midrange you had. Something like having the whole manifold extrudehoned would possibly give you the gains you're looking for out of it.

That oil spot just inside your intake is probably from having your valve cover vented into your intake pipe and the little bit of reversion you'd get up in that tube from higher RPM would probably wipe the wall on that sharp turn.

OH_1fstgsr

iTrader: (2)

I thought this might be an issue with the changes I would be making, but I have some changes from my orginal that might off-set the loses. I am now running a 3" CAI not the GSR 2.75". Not a big difference but maybe enough. I am now running a V-Stack that I did not have before, a few more hp.
One last thing that will change is the injectors, I will be replacing the RC370's with FIC525's. I am hoping these changes will off set the low end loses that might occure. I guess I will have to wait and see.

00Red_SiR

One note about the FIC injectors, I was told that unless you go with the 775cc or larger, you don't get the "enhanced" spray pattern (divided) which is beneficial on a 4v/cyl motor. The 525's would be similar to installing RDX injectors, better than stock/RC injectors but only slightly when compared to the 900/1000cc Bosch injectors.

FYI I will be testing out a set of the Bosch 900cc FIC injectors on my car next month when I do all the tuning and testing down at IMW in Pa.

raverx3m

iTrader: (1)

lol i almost ordered a set of 725 cc from xenocron how come the bigger injectors have better spray pattern? i thought smaller ones atomize fuel better.
sorry to get this off track a lil bit.

knife edge the throttle body valve and the IAB valves as well.
i did that for the TB wasnt too hard( didnt have the IAB plate in mine)

which you cant really see but i also rounded the screws and made them even with surface, and rounded the butterfly holder?

DDTECH

Beat it to death.

OH_1fstgsr

iTrader: (2)

I will double check with my tuner about this, he is a distributor for FIC.

My throttle body already has this done. This is exactly what will be done to the butterflys.

Natural Aspirations

I would be willing to bet removing the dual runners and designing a upper section that flows better and allows better air distribution would be a great improvement

Similar to this.

95skunkedgsr

yea just ask nah2b to make you a top hafe of the intake mani for the gsr mani and throw a ford T-body on it

Natural Aspirations

What about designing a single oval butterfly plate for the lower section and adding a taper to the secondary runners? This would slightly increase the area and shorten the runner a tad along with removing the upper webbing.

I have actually been thinking about this a lot myself.

raverx3m

iTrader: (1)

we can call it the SAB (SAUSAGE AIR BYPASS)

00Red_SiR

I just felt my butt cheeks clench up when I read this...lol

1.5Slowmatic

i was thinking of randy's(NAH2B) intake as well like the RLZ one. I mean a lot of the F22 guys use the H manifold Frankenstein intake and get the butterflys removed and it works well for them. Don't see why it couldnt work here either

gutted-dx

iTrader: (1)

I would think a test pipe itself, would net around 3-4hp.

Sparkles

What about designing a single oval butterfly plate for the lower section and adding a taper to the secondary runners? This would slightly increase the area and shorten the runner a tad along with removing the upper webbing.

I have actually been thinking about this a lot myself.[/QUOTE]

This is a great idea! You'd get the strong low/mid power with much more volume for the top end. You would have to build one big rectangular butterfly.

OH_1fstgsr

iTrader: (2)

Maybe. Didn't look at like that.

Status Update.
Plenum will be cut out.
Butterflys will be worked over.
So how will the air smoothly enter the holes in the butterfly plate? Aluminum expoy, I hope. We should be able to fill in the openings and create what ever taper we'd like.
So all the area in red will have material added.

Lower runner section portmatch to butterfly section.

Slain

cant wait to see some progress on this.