1-7/8 or 1-3/4 4 into 1 extractors for my VE SS

[kingkava]

I wanted to know whether I should go for 1-7/8" extractors of 1-3/4"? they're both 4 into 1 style, along with 100cpsi high flow cats.
I provide a bit of a background of the car as I have had some minor modifications done to the car:
2010 VE SS Automatic.
LS3 camshaft
VCM OTR intake
Fitted and custom dyno tuned at Russo performance, which produced 260rwkw

He said he will do the 1-3/4 or 1-7/8 extractors for the same price for me (so its up to me), however he recommended 1-3/4"
So all up it will be extractors, high flow cats and re-tune all for $1750

any suggestions would be great.

cheers

[Woodchukka]

Remember you have to get exhaust gas out of the heads first so 1 3/4 will be more than up to the job. 1 7/8 are really too big unless it is in a blown application.

[kingkava]

Yeah makes sense. Not putting in a supercharger anytime soon so 1-3/4" is probably the way to go.
Cheers

[QldKev]

I'd stay 1 3/4, 1 7/8 are for blown or really big cam setups. The bigger pipes will give a better sound thou.

[RED R8]

At the same price is there any actual downside to going the 1 7/8 ? if they make the same power across the rev range either way the bigger pipes may just future proof you?

[Micks]

Russo boys know their stuff & would go with their recommendation. Your engine had a DOD delete too being a 2010 I take it?

[kingkava]

Yeah he did mention that i would lose a bit of power by going the bigger size....yeah they know their stuff thats why im going with his recommendation.

On top of the mods i mentioned, i have had a MAFless tune and the AFM deleted. Im not sure what a DOD is though....

I'll post up new rwkw and torque values once its all done (end of next week)

[Micks]

DOD is displacement on demand in Aus we call it active fuel management. Reckon yours being an auto should pickup approx another 15rwkw+ with those pipes & high flow cats.

[RED R8]

Yeah he did mention that i would lose a bit of power by going the bigger size....yeah they know their stuff thats why im going with his recommendation.

On top of the mods i mentioned, i have had a MAFless tune and the AFM deleted. Im not sure what a DOD is though....

I'll post up new rwkw and torque values once its all done (end of next week)

Ah OK....if not going blower etc down the track then the 3/4 makes sense.

[kingkava]

Another 15rwkw would be great but i lose traction all the way up to 120km/h the way it, so not sure how easy it will be to drive with more power.....its obvious the stock traction control system was designed for the original 270kw engine so its pretty much useless now.

[sjhugh]

Another 15rwkw would be great but i lose traction all the way up to 120km/h the way it, so not sure how easy it will be to drive with more power.....its obvious the stock traction control system was designed for the original 270kw engine so its pretty much useless now.

260kw at the wheels is not huge power.

You could expect a little slippage but I can’t say I’ve ever had any problem with the traction control on a VE with only that amount of power increase unless I switch the system off.

Maybe your tyres are the problem?

On a side note, that LS3 cam doesn’t seem to be doing much.

[Xjas]

Another 15rwkw would be great but i lose traction all the way up to 120km/h the way it, so not sure how easy it will be to drive with more power.....its obvious the stock traction control system was designed for the original 270kw engine so its pretty much useless now.

Forget extractors, use the money to buy some better tyres.

[Micks]

260kw at the wheels is not huge power.

You could expect a little slippage but I can’t say I’ve ever had any problem with the traction control on a VE with only that amount of power increase unless I switch the system off.

Maybe your tyres are the problem?

On a side note, that LS3 cam doesn’t seem to be doing much.

A 6L DOD delete with a LS3 cam will net about a 60kw increase depending how conservative the tune?
An A6 VE will generally do 200-210rwkw stock. So the Op's 260 without full pipes is good & a healthy increase with a stealth cam.
My DOD deleted L76 M6 netted 278rwkw there be the difference with the trannies.

[BLACK 346]

Another 15rwkw would be great but i lose traction all the way up to 120km/h the way it, so not sure how easy it will be to drive with more power.....its obvious the stock traction control system was designed for the original 270kw engine so its pretty much useless now.

Is the car custom tuned? I was advised by my tuner that the traction control in VE's can be adjusted in the tune to be as intrusive or unintrusive as you want.

[amckiwi]

I am very happy with the 1 7/8 pacemakers 100 cpi cats and HM Perry catback on my 09 (no AFM) manual VE Ute.
I also have a DUS OTR and no other mods.
This combo makes 289RWK on injected LPG 10 less on petrol.
The ute made over 230rwkw stock with less than 5,000ks on it which I think is at the upper end to begin with
Stu
My traction control was massaged a little as part of the tune.