for sale maybe: My 3inch mandrel exhaust and downpipes.

[AllBeItMine]

Hey guys, i have been toying with the idea of replacing my exhaust with a twin setup. thought it would be cool to have one exhaust system per bank. kinda V8 style. I will only do it if i can sell the exhaust i got.

Its a 3inch mandrel bent all the way, its got one resonator and a performance muffler on the end. this hooks up to the 2.5inch mandrel bent custom downpipes.

It will be a bolt on for any 96+ twin turbo galant vr4 and use all the standard mounting points. i'm not 100% but it should fit on a legnum as well.

The performance difference is quite dramatic. It raises stock boost to around 10psi and allows the engine to rev freely past 7000rpm rather than that feeling you get of slowing down at around 5500rpm.

The best part is the sound. Call me a ricer, call me a boy racer but bugger ya, my car sounds absolutely mint. its got that soft purr at idle, that ducatti rumble at mid throttle and it screams like an externally wastegated R34GTR race car when its being thrashed.

I'm just after doing something different, these pipes have served me well but i want to try something new. they are about 6-8months old and will be cleaned up and re-painted black before sale. currently on the car. can have fitting arranged at no cost.

anybody interested?

[enigma]

Hey guys, i have been toying with the idea of replacing my exhaust with twin setup. thought it would be cool to have one exhaust system per bank. kinda V8 style. I will only do i if i can sell the exhaust i got.



May not be that easy, as you will have to put an 02 sensor in each bank. I would suggest keeping your downpipe and splitting in to 2 branches towards the back of the car like I have done.

[AllBeItMine]

why would i need the o2 sensor to read both pipes? its just a percentage isn't it?

there are alot of twin exhaust systems on cars with only one 02 sensor...

[Kieran]

why would i need the o2 sensor to read both pipes? its just a percentage isn't it?

there are alot of twin exhaust systems on cars with only one 02 sensor...

Ok, two things...

You need two sensors to ensure that one bank doesn't start leaning out... One bank may be being fed nicely, but if one or two cylinders on a bank are being starved a bit, it could be curtains..

However, check your engine first - Not all V6s may have this, I don't know about the VR-4, but the V6-24's exhaust system changed during it's lifetime (At the time of the facelifts I think) and went from a single Oxygen sensor in the downpipe to one in each manifold - Which would make things easier!

[enigma]

my 99 VR4 only has one O2 sensor, I certainly wouldn't want to run with only one bank being monitored!

2 sensors is the only solution really, not sure how you would wire them together to give an average (which would give you some protection!)

[Kieran]

Just been out to look under the Bonnet, and Hordak is indeed carrying two O2 sensors - Makes sense really, as I remember my dealer saying that Mitsubishi had to change the emissions gear during the car's lifetime to keep compliance.

[Kenneth]

my 99 VR4 only has one O2 sensor, I certainly wouldn't want to run with only one bank being monitored!

2 sensors is the only solution really, not sure how you would wire them together to give an average (which would give you some protection!)

My thoughts would be to use a micro-controller to monitor both and send back the leanest reading. You could then manually monitor for variations and such, but it would be pretty safe for the engine.

[Kenneth]

AllBeItMine, whats happening with that group buy thing? im more interested in the down pipes, but if you are selling your whole system I could be interested, depending on what you want for it.

[AllBeItMine]

okay - i could understand if this was like a 300zz with seperate intakes per bank... but its not. there is one throttle body, and the cylinders all get fed from the same pot. so how could one bank lean out over another?

annnyway - maybe its not such a good idea. i will have a chat with some people to find out whats the dilly on the O2 thing.

i will update the group buy thread soon. we are still waiting on a price from a manufacturing company in australia.

[wirdy]

I'm no expert, but I think your theory would be okay if the VR4 was single point injection on each bank.

With multi-point injection one cylinder in a bank could still run very lean and the ECU would know nothing about it. It's pretty unlikely, however- do you want to risk it?....I don't think I would.

You do have one saving grace - you're geographically closer to import a fresh parted engine though.

[AllBeItMine]

okay - after some more talking - this is just too hard. the length of pipes need to be the same, so the one coming off the back turbo would need to do a detour somewhere along the underside of the car to make up for the longer front pipe.

just too hard. will stick with what i got. work fine anyway

[marsh]

okay - after some more talking - this is just too hard. the length of pipes need to be the same, so the one coming off the back turbo would need to do a detour somewhere along the underside of the car to make up for the longer front pipe.

just too hard. will stick with what i got. work fine anyway


I was thinking that. How would you manage to keep them the same length?, one from the back bank would have to run a full lap of the back of the car to be equal.

[i3ooyah]

AllBeItMine, whats happening with that group buy thing? im more interested in the down pipes, but if you are selling your whole system I could be interested, depending on what you want for it.

what group buy? i'll be interested in that

[AllBeItMine]

I was thinking that. How would you manage to keep them the same length?, one from the back bank would have to run a full lap of the back of the car to be equal.


i was thinking of having one of the pipes exiting on the right side of the car where as the shorter, back bank pipe would exit on the left, doing a turn around the dif. would be more or less the same length... with a balancer pipe for the o2 sensor it wouldn't matter so much anyway.

[marsh]

i was thinking of having one of the pipes exiting on the right side of the car where as the shorter, back bank pipe would exit on the left, doing a turn around the dif. would be more or less the same length... with a balancer pipe for the o2 sensor it wouldn't matter so much anyway.

Ignore the complications, some engineering could make it work.

It'd be the dogs gonads. :2thumbsup

[Sulli]

Regarding the unequal length. Don't Imprezas have unequal length headers, which give the boxer engine that awesome sound?
An upgrade on the Scooby is to fit equal length headers, which I think improves responsiveness and power slightly, but loses the boxer rumble.
Therefore, if you have unequal length headers, you probably wouldn't have a problem, and a unique sounding VR4??

[paulmc]

I thought that at WOT the lambda had nothing to do with the mixture as the ecu just reverts to its map. The lambda is not very accurate anyway and can only measure a very small range accurately ( it is fine for just about measurments, but the ecu wont use these) so the ecu runs from what info it has in its map.

[Rally205]

I thought that at WOT the lambda had nothing to do with the mixture as the ecu just reverts to its map. The lambda is not very accurate anyway and can only measure a very small range accurately ( it is fine for just about measurments, but the ecu wont use these) so the ecu runs from what info it has in its map.


Thats correct. The ECU only uses the Lambda probe for closed loop running at idle. The response time of the probe is far too slow to give any reliable input at any other throttle position. The ecu does not adapt to different mixture readings it simply relies on its preset fuel/ignition map in relation to throttle position/ AFM , intake temp and manifold pressure as far as I am aware.

[bernmc]

I've been speaking to me Dear Olde Dad about this - he did a lot of exhaust/gas flow work for Ford Motor Racing when he was a lad. He still does custom exhausts. He thinks a V6 into separate banks is one of the nicest sounding exhausts out there. He's doing some research into the lambda sensors too, but his initial response was that it shouldn't matter...

He's not too familiar with the sensors & systems on Jap cars though.

[valmes]

Does it promise any performance gains? Why brake what's working?

[AllBeItMine]

well. some pros and cons here.

if i could get somebody to buy my existing exhaust i would do it. otherwise i wont bother.

any offers? anybody?

[Kenneth]

well. some pros and cons here.

if i could get somebody to buy my existing exhaust i would do it. otherwise i wont bother.

any offers? anybody?

im currently trying to scrape enough cash together to pay $2500 for tickets to UK in august. (gotta pay by 28th of feb to get a "good deal") give me a couple of weeks and I will definatly be interested.

What exactly are you offering? the whole lot?

[AllBeItMine]

yeah. the whole lot.

i have pictures. but the exhaust will be taken off the car, completely cleaned up, resprayed and re-fitted to your car.

i paid $850 for the exhaust and $500 for the dumpipes. would probably need to sell for around $1000.

its only been on the car for about 6months. and in good nick.