egb18c5

your thinking about these builds like F1 engines, very detailed, which isn't exactly wrong but its not the foot you want to start off with, especially in your case. start with the basics and move forward from there.

the PX manifold proves itself as a nice manifold for the rpm range it was made for. there's a few people who did back to back testing with a unmodified PX mani. if your looking for EXACT combinations like yours, your search results will be very limited.

he also posted a graph with a unmodified PX mani, you might have to do some extra digging, but its there. searching can go a long way.

slowsleeper

Here's what the setup made on a SHELF unmodded Performer X:


The Performer X IMO is my preferred IM for the 1.8 stock sleeve engines, next or new IM that I may want to get my hands on would be the new Skunk Ultra Street. I am sure with the proper setup, making power with either of these IM will be a piece of cake.

SR20S13

https://honda-tech.com/forums/all-motor-naturally-aspirated-44/attn-people-who-rebuilding-gsrs-hate-ctr-pistons-2931459/

this thread, 81mm bore CTR Pistons, GSR crank/head and 235whp on a stock performer x

egb18c5

it will be there when your ready

FlewByU352

How does camshaft choice play a role in manifold selection? I'm wondering if certain cams a short manifold like the ITR would be better than the PX? Or does this prove far superior on everything with a 1.8L?

Rocket

Big, big role.

raverx3m

iTrader: (1)

rocket is it possible for a simple explanation?
there was a discussion in oher threads but i didnt understand much of it lol.


and throttle body included also in the equation.

Rocket

Two ways :
1. Intake charge momentum and
2. Resonance waves (harmonics)

DazeMS

1. Valve opens pulls air in VIA lift X duration.

2. Frequency generated by incoming air that responds to length and volume of intake and plenum. The dual plane runners in some hondas such as the GSR and prelude (h22a) are examples of a "tuned" harmonic response. This is tested through points in engine rpm. or Variable Resonance Induction System or VRIS for short. Harmonics is something I feel honda has not experimented enough with shrug.. Instead, they went straight for VTEC.

Rocket

Harmonics is not as effective as momentum, i. e. Velocity of charge (determined by cross-section) and the mass of the charge, length of the charge.

FlewByU352

So does this become an expensive trial and error? Or can a formula be used to calculate air resonance length, speed, and volume? When does velocity become a restriction on volume to have negative effects?

SR20S13

Its also trail and error, even with a formula they don't always work.

dc4teg95

Would skunk 2 tuner 2 cams be ok with this manifold? My motor build plan is as follows

Head:
Itr head
Skunk tuner 2 with vt
PX manifold (already have)
65mm tb or stock 62 tapered to 70
Toda rep header (already have)
3" sri with arm dry flow filter (already have)
Rdx injectors

Block:
Gsr block
Ls crank machined to clear oil squirters and balanced
Ls rods shot peened
ARP rod bolts
ARP head studs
Rs machine itr pistons 81.5mm
OEM head gasket
Shaved and balanced OEM crank pulley
Comp clutch stage 1.5 (already have)
Exedy 7.5 flywheel (already have)

I don't plan to rev much higher then 85-8800rpm. Just building a fun street motor.

DazeMS

that is very true . Resonant response changes so frequently, that it is inefficient to tune for. Mazda was one of the few who tried to tune for Harmonics with Intake plenums at several different RPM points. the VRIS setup on their kL series v6 motors, adjusted three different times to optimize torque throughout the engines rpm. It was pretty effective in keeping the torque up and those motors usually made almost the same in hp and torque to the wheels. But, VVT is more efficient and cost effective.

Rocket

Expensive as in trying different manifolds? If you are designing a manifold and got to pay $30K for a mold, it's expensive and you may want to do software simulations, but it still needs to be validated with real world testing.

Just look at the 230whp 82mm LSVTEC. PX works real good, I always liked it from the beginning, but people didn't make good power with it (for whatever reasons), till someone built a good combo. If that is your goal, model you build after that. A lot of the Edelbrock stuff is very well designed.

Couple things to note about the PX:

Proper TB angle into the plenum.
Proper plenum overhang on the no. 1 (cylinder) runner
Proper length for harmonic tuning: for 8.4-10K range assuming a 14" length from valve to runner entry (you guys can check my guess here, http://www.bgsoflex.com/intakeln.html)
High velocity runner cross-section

These comments are based on my eyeball observation.

DazeMS

PARTS DAY! yay.. Dont know when I am going to get around to putting it on, but this manifold is HUGE compared to the sk2 pro. Also, looking at the IM flange, the px is properly angled with the ports!! OMG yay.. the TB opening is bigger then stock, but seems smaller then 68mm.. more like 65mm.. I will have to get it port matched etc.

I did not get a IM flange gasket, not sure if that was supposed to come with or not, but it came with the TB gasket. I noticed that something, the factory TB gasket does not match the spacing of the edelbrock gasket, but the edelbrock matches up perfectly with the PX tb opening. I wonder if the same is said for the IM flange gaskets. hmm, could be the reason some think it looks "off", but the ports and injector boss' do not seem misaligned, so perhaps it was an error on only a small batch of earlier Px's ?

gutted-dx

iTrader: (1)

They only come with a tb gasket. Interested in your results i have one on my b20vtec and my motor loves it.

raverx3m

iTrader: (1)

figure I post this here since its related also


GREEN LINE previous tune from march 28 with about 45 degrees temperature outside
RED LINE today jun 27 with 74 degrees temperature

removed power steering
added 1.5 inch to intake length and rolled flanged the intake pipe to have smooth transition from 3 inch to 3.5 inch pipe
whatever I did it smoothed out that choppy area between 6000 and 7200 rpm

second chart is my custom intake VS whale *****
RED line-whale *****, GREEN line my intake

FlewByU352

I'd consider those gains from removing the power steering alone. Belt driven power steering is give or take a 5whp eater. I didn't buy into it robbing that much as people said until I did it for myself on the rollers. My setup put down 203WHP without it.

raverx3m

iTrader: (1)

7tq gain in the low end is definitely noticeable

gutted-dx

iTrader: (1)

Nice gains! The whale intake performed a little better than i expected too.

raverx3m

iTrader: (1)

It lost power compared to mine

d15Beta

wonder if the Px would work (gain some)
on a high strung b16

raverx3m

iTrader: (1)

It falls off at 8000 do probably not for high revving

d15Beta

good eye.. both those above looks to be in that area...


although I had assumed its the cam size to displacement deal

this manifold might be "big" on a 1.6L ... hmmm I guess that's worth a try and dyno and share here?