Custom Y-Pipe For A32/A33

[ongteckweng]

mafia bro...wher about u did that? any pics on the final product? the 2 precats r from the Y-pipe right...

 

[MafiaRide]

Somewhere near leisure mall, cheras where there are alot of shoplots. If you know the row with 2 pet shops, the exhaust shop is in between. Yup, the 2 precats are from the y-pipe. Replace with a flex pipe and a bullet.
Let me know and I might be able to draw you a map.

No pics lah bro cause it doesn't look as good as the chrome ones you showed :-)

 

[defcon1]

Mafia...actually, I'd have done it without the flex pipe and bullet. They tend to slow down the exhaust flow velocity...bad for low rev performance.

Or maybe the bullet (if well designed)...but not the flex pipe.

And the kick you feel at 4500 rpm are the butterfly valves in the plenum opening. You could have them permanently open, but your FC would go to hell...

 

[ongteckweng]

Mafia...actually, I'd have done it without the flex pipe and bullet. They tend to slow down the exhaust flow velocity...bad for low rev performance.

Or maybe the bullet (if well designed)...but not the flex pipe.

And the kick you feel at 4500 rpm are the butterfly valves in the plenum opening. You could have them permanently open, but your FC would go to hell...

i would say its the bullet...the flex pipe its to reduce the vibration of the whole exhaust system right??

 

[defcon1]

i would say its the bullet...the flex pipe its to reduce the vibration of the whole exhaust system right??

Some bullets are designed to spiral the exhaust out. This creates a vortex effect that sucks the exhaust out of the headers.

The flex is designed to take into consideration engine movement...includes vibrations and shifts during launches. Probably a good idea to have.

 

[MafiaRide]

So happen one of the precat is near the bend, so a flex pipe was used, as you mentioned to reduce vibrations during hard acceleration.

The bullet I use is the one without protrusion or spirals. I've read somewhere that these things, if not designed correctly can create more backpressure than a stock catcon.

My low revs didn't really suffer actually. What I felt after changing was that the engine was slightly more response and eager to move when I throttle up a bit. As for the second plenum, yeah did some reading and ask the nissan mechs, they said our engine has that. The difference I felt was more dramatic comparing with the stock catcon and my current setup. Maybe there is now less restriction to overcome for the gasses to exit, hence better flow at WOT.

Who knows but as long as I enjoy my ride who cares :-)

 

[ongteckweng]

So happen one of the precat is near the bend, so a flex pipe was used, as you mentioned to reduce vibrations during hard acceleration.

The bullet I use is the one without protrusion or spirals. I've read somewhere that these things, if not designed correctly can create more backpressure than a stock catcon.

My low revs didn't really suffer actually. What I felt after changing was that the engine was slightly more response and eager to move when I throttle up a bit. As for the second plenum, yeah did some reading and ask the nissan mechs, they said our engine has that. The difference I felt was more dramatic comparing with the stock catcon and my current setup. Maybe there is now less restriction to overcome for the gasses to exit, hence better flow at WOT.

Who knows but as long as I enjoy my ride who cares :-)

u r right mate...its our car...its our money...hahaha

 

[defcon1]

I'm thinking that maybe I could modify the opening rate of the butterflies. The butterflies are controlled by the vacuum actuator on the right of the engine cover. Adding a vacuum booster and a valve will allow us to meter the amount of vacuum to that actuator and define whether it opens earlier or later.

It's somewhat similar to the butterfly valves in the inlet manifold of my Celica except that those were in the inlet runners...a much better configuration, in my opinion cos it limits the amount of air agitation prior to entry into the cylinders.

Also, you're right about the bullet. A badly designed one can actually cause a lot of back pressure...which is why, I would prefer to go without one...noise permitting, that is... :)

...somehow, it's bad enough being called a "riceboy"...but at my age, "rice-man" just doesn't cut it...

 

[ongteckweng]

I'm thinking that maybe I could modify the opening rate of the butterflies. The butterflies are controlled by the vacuum actuator on the right of the engine cover. Adding a vacuum booster and a valve will allow us to meter the amount of vacuum to that actuator and define whether it opens earlier or later.

It's somewhat similar to the butterfly valves in the inlet manifold of my Celica except that those were in the inlet runners...a much better configuration, in my opinion cos it limits the amount of air agitation prior to entry into the cylinders.

Also, you're right about the bullet. A badly designed one can actually cause a lot of back pressure...which is why, I would prefer to go without one...noise permitting, that is... :)

...somehow, it's bad enough being called a "riceboy"...but at my age, "rice-man" just doesn't cut it...

take out the bullet...sound proof ur cabin....best of both world...

 

[MafiaRide]

That is an interesting thought. I'm not sure for the cefiro, is the actuator driven by vacuum or electronic but it sure looks like vacuum. For the perdana, it is electronically controlled by the ecu to open at 5500.

Just be careful when doing this. I believe it is designed to be used after a certain rpm. If the incoming air is too slow, your concern is that the air coming in from the 2nd plenum will cause turbulence to the incoming stream resulting in a not so clean burn. But after certain rpm, the air is being sucked in so fast opening the 2nd plenum will have no effect but rather gain a little more power.

I'd say if you want to play, port a whole on the other side of the whole intake manifold [where the intake pipe connects to the intake manifold. Well, the opposite side of this]. I've seen others did it for other cars. You get true dual air intake. You will be taking in twice the volume of air. But the problem is you need to find the right diameter for the pipe so as not to lose intake velocity.

Its interesting how combustion engine works :-)

 

[defcon1]

Um...you'd also need to be able to measure the volume of air going in at different rpm's and provide the necessary enrichment...

 

[ongteckweng]

Um...you'd also need to be able to measure the volume of air going in at different rpm's and provide the necessary enrichment...

chris...best way for power still turbo...
no need so "mafan"...

 

[defcon1]

Ai yoh!!! You cannot imagine how "mafan" a turbo can be...I drove one for 6 years...

a) White smoke every 1.5 years, so need new turbo seal.
b) Engine very hot, all rubber/plastic parts including harness damn brittle. Finally changed harness.
c) FC? What's FC?
d) Have to make it a habit to check coolant level every week...
e) Use fully synthetic oil also have to change every 5000 km...too hot until oil also turn to carbon.
f) Any mod involves high level engineering, complex electronics...and deep pockets...
g) Tyres mininum RM 650 per piece.

...should I go on?...

 

[ongteckweng]

Ai yoh!!! You cannot imagine how "mafan" a turbo can be...I drove one for 6 years...

a) White smoke every 1.5 years, so need new turbo seal.
b) Engine very hot, all rubber/plastic parts including harness damn brittle. Finally changed harness.
c) FC? What's FC?
d) Have to make it a habit to check coolant level every week...
e) Use fully synthetic oil also have to change every 5000 km...too hot until oil also turn to carbon.
f) Any mod involves high level engineering, complex electronics...and deep pockets...
g) Tyres mininum RM 650 per piece.

...should I go on?...

of course la...u r clocking an average of 204km/h from KL to Tuas...

and u expect a problem free car???!! even F1's engine last 2 races max!!

 

[defcon1]

of course la...u r clocking an average of 204km/h from KL to Tuas...

and u expect a problem free car???!! even F1's engine last 2 races max!!

Heh...this one lasted about 120 round trips...

 

[MafiaRide]

Turbo cars are not as easy to maintain bro ong. Used to have a Eterna tt with 350whp running 1.1 bar boost, nitrous, haltech, O2 commander, etc. Literally reached topspeed of 260kmh but damn scary already. On launch, the front will hop.
What defcon say is very true. Enjoyed many kills with it but maintenance is a nitemare. Personally, I've tried it and I intend to keep it that way, ie: history. Nothing like the realibility of NA cars, if you don't over do it. If want more kick, get a 5L V12.

 

[ongteckweng]

Heh...this one lasted about 120 round trips...

yeah...but their engine costs 100,000 times more than ours....

maybe a 1,000,000 times more!

 

[ongteckweng]

Turbo cars are not as easy to maintain bro ong. Used to have a Eterna tt with 350whp running 1.1 bar boost, nitrous, haltech, O2 commander, etc. Literally reached topspeed of 260kmh but damn scary already. On launch, the front will hop.
What defcon say is very true. Enjoyed many kills with it but maintenance is a nitemare. Personally, I've tried it and I intend to keep it that way, ie: history. Nothing like the realibility of NA cars, if you don't over do it. If want more kick, get a 5L V12.

mafia bro...tell me about it...

i had a Saga with a VR4 engine for 4 yrs...lots of torque.....killed many suppose to be performance cars..break 4 gearboxes in a year...

3 sets of tyres every yr...and its the best time of driving in my life...well, until now...

 

[MafiaRide]

I do agree turbo cars are sweet to drive. Still can't get over the g-force. If I remember correctly, mine had something like 410NM of torque. My gearbox was fine just that I fried a piston. Tyres lasted me quite long. I only play with cars on the highway or lonely roads with long sweeping corners. Tight corners don't want to play cause front heavy and understeers easily.

Nailed M5, alfa 166, wiralution, wajevo, etc. Manage to keep up with an M3 but could not overtake. I love my perdana tt but was giving me too much trouble because of my yearn for more power. The eterna block was not the strongest.

The most funniest is this incident where I was coming back from partying travelling on the sungai besi highway at about 1+am. This kancil turbo was sticking so close to my ass. Armed my NOS switch and floor the pedal. Lost him in 3 seconds flat. Then slowed down and let them pass. Saw their faces in disbelief. This is a classic :-)

Since I sold her off, I don't drive like I used to. Much more subdued. Hardly pass 120kmh on highway. Now I make way for people on the fast lane. Last time floor the pedal :-) Silly things we do when young.

PS - I only "play" when provoked. Let's hear some of your kill stories.

 

[ongteckweng]

oh well...i dont do it often in public road...mostly in Batu 3 track...

but few cars that i remember outgunned n still laughing when i think about it...
i were travelling along the mrr2 kepong bridge towards Batu Caves around 120km/h...then came along a yellow evo 7, tailgating me....well, i move to the middle lane when when he tried to pass u, i just floored it pass my 180km/h mark on the meter n the evo was 200 metres away...slow down n let him pass...the best part...we were heading to the same workshop!!! imagine his face when he saw my car... of course he quickly go away....:lol: