v6 3.5 exhaust?

[jonhart80]

Has anyone had a v6 3.5 petrol fitted with an new exhaust. what was the cost and was there any benfits?

[Homer]

Mate PM slimv6.
He's just bought some headers from RPW in Perth and was fitting some pipes up. Would be interesting to see how he went - RPW will ship - he is in Africa.

[slimv6]

yeah, I first too al the cats out. but there;s bit of fabrication work to do on the headers to get the rest of the system to fit.

Watch out for downstream lambda sensors, they will need to be moved and defoulers installed, if you taking the catalytics out...

I got aout 15%, at 1600m above sea level. it's looney at the coast...

[jonhart80]

Just got my exhaust done All places recomended that the stock system was good and the cost to get new pipe bent was not worth the cost. They recomended just to remove the muffler and put in a high flow glass packed sports muffler. Got a little more throttle responce and will see what the fuel econ is like this tank. Great sound sounds tuff.

[Homer]

Just so I am on the same page...you still have the std pipes and all 3 std cats and put on a new sports muffler?

Would like to hear the results as I got a reasonable result from replacing the 3rd cat with 100 cell hi flow.

May do a muffler if it improves yours a bit.

[jonhart80]

Yes all standard pipes just rear muffler done. Did you get any improvement with the new cat?

[Homer]

Yeah mate, about 5-6KW judging by the dyno figures - just felt crisper - some of the measured KW gain could also have been the engine loosening up after 20,000 k's from the first time I dyno'd it.

Doesn't sound much but it all counts.

Exhaust note sounds better too - but not like the dunnydore drone.

[slimv6]

lose the 3rd cat! Technically, there's still two in there...

I got about 15hp from that and the new box, kept the same dia as before the flange. sounds great, goes great...

homer, I haven't had a gap to fit the daym pipes, but I got some fab to do cause there's only place for 1 lambda sensor, need to put in 4...

The other thing that i'm a bit nervous about is that the primary headers on the RHS are about 2wice as long as the ones on the LHS... Logic tells me that the best configuration is gonna be same longth on all 6. It is why we change these things, isn't it?

[slimv6]

O, and remember I'm 1650MASL....

[Homer]

Hey mate.

I couldn't get anyone to remove the 3rd cat altogether. The best I could do was swap it with the highest flow cat available. Made a difference.

I would think same length headers would be the norm too? Maybe they know something different.....

Must feel good when you get to drive it at sea level occasionally. I was touring around and got up near your height and threw my first engine light about a year ago.
Mustn't have liked the tune in the thin air.

[slimv6]

heh heh...

It's a new vehicle at the seaside!

I think I'm gonna try tackle my pipe on the weekend. Just a bit concerned about the sensors tho... Will pot them to the FB group and link them here.

Then, it's dyno time!

I only ever had a engine light on the P0302 error, seems like a intermittent bad lead. 4 times in total of 160000km...

[Homer]

Mine does the same PO303 every month or so. Yours is no 2 cyl, mine 3cyl.

Talked to the service guys last week with the light still on and no joy happening there without blood being drawn. Must have shite leads or plugs from std?

I can feel mine when it misses. Only seems to be under heavy load or flogging it a bit and only the once - then clears.
Was towing up a range with foot to the boards and it felt like a limp mode one time, but all good after the load is reduced again

[slimv6]

yeah, same shit. I reckon those fongkong leads are to blame... I haven't had it for a while tho. plugs were hanged recently, but I definitely reckon a lead is the culprit.

just a bit of a bitch to check the plug leads and plugs, plenum off and well, we knkow what a crap job that is...

[Homer]

Yeah I'm going to get them to change no 3 lead when the plugs are done.
I'll have to pay for it, but it's better than the frustration of telling them over and over what the problem is and them "not being able to find it"....

[slimv6]

Gents!

I am busy bolting all the good stuff up! beena bit hectic, but should be done by friday...

Only 2 snags I got from RPW headers,
1. No place for lambda's.so I'm cuting new ones and installing them at the collectors. Should give an even reading for both banks. Also trying to keep them at the same distance, so there's not too much variation when the headers cool off. They are different lengths.. (WTF?)
2. The last collector, the 2:1 does not fit with the rest of my system, so refabricating another collector with 2x51mm in and 1x64mm out.

as for the restof the system, it's done about 100000km, stainless with no queries.may just have to do some slight adjustments to make sure it's hanging on the rubbers properly.

Stay tuned for more dyno figures...

(I'll be gutted if there's not much gain...)

Oh, and just a word to the wiser, if there are defoulers fitted on your downstream lambda sensors, make sure the defoulers have enough space insode to accomodate the whole senso. The bloody git who installed the last set crushed the bottom of the sensors. feck.

[slimv6]

ANd the headers are in!!!

only one concern, there's not very effective port matching with the rpw headers, suspect it could be for a 3.0...

But, again, from 3000, it's a different vehicle!

Dyno booked for tuesday. hopefully they can set the ignition timing on it, as it's only fuelling for the mo...

[Homer]

So the ports are mis aligned a bit? That would lose some of the flow benefit you're getting from the cat removal....bet it sounds good.

Looking forward to the dyno results

[salt36]

Me too homer

Watching with interest....