4.5 Exhaust

[Alitis007]

Hi all, i'm thinking of making up an exhaust for my 4.5 to get the motor to breath better. Just want to know what sizes do people have on theirs and if its worth doing ?? I was planning to get a set of extractor/ header pipes, 2.5" high flow cat, a couple of high flow/ sports mufflers and make it out of 304 stainless steel. I was thinking 2.5" mandrel bent but seeing its a fairly large motor would it be better to run the exhaust from the extractors a 2" siamese style system for flow and air speed?

Cheers George.

[Winnie]

You'd get good results from a 2.75"

[Alitis007]

I was thinking that but i'm not sure how pricey it will be, plus its only temporary for a couple of months or so till i save the $$ up to throw something with a bit more kick under the bonnet!! Plus giving it a full boot to stay at 100 up hills makes the wheels start turning in head lol and looking at the straw it breaths thru its a good place to start.

[Winnie]

I wouldn't bother if it's going to be redundant in a couple of months?

[BigRAWesty]

Why waste good money..
What are you looking at dropping in it?
And if your looking for power why just turbo the 4.5?

Kallen Westbrook
Owner of
Westy's Accessories

[Alitis007]

I wouldn't bother if it's going to be redundant in a couple of months?

Just the extractors will be mate!!

Why waste good money..
What are you looking at dropping in it?
And if your looking for power why just turbo the 4.5?

Kallen Westbrook
Owner of
Westy's Accessories

The thought of a LS1 is bouncing around in my head, and if i make it right that will be half my zorst made all i will need to do is add a cat, x pipe and change the rear muffler. I have 2 magnaflow mufflers laying around and a couple of meters of 2.5" pipe just need the headers, cat and a pre bent mandrel or 2 coz i might have a few laying around too.

[nissannewby]

6.0 Chev all the way have a look at russ81'build up in the DIY section.

[Alitis007]

6.0 Chev all the way have a look at russ81'build up in the DIY section.

I was thinking more on the lines of fit the gena in first and when it gets a little "tired" slap together a 7ltr stroker kit, i always wanted a 427 ci or charge it. Its all a matter of funds as always!

[nissannewby]

You can fit 582 in a gu easy enough

[threedogs]

Been there done that with the 350 Chev conversion. NEVER again. Forget the 350 diesel V8 too, hopeless engine. Stick with what you have. Look at YTUBE and see what the Saudis can do to a 4.5 or 4.8 and a turbo. IT WILL BLOW YOUR MIND. mind you fuels only 13 cents a litre. I have mates with 4.5 and 4.8 GQ utes that pull a 14 sec 1/4 mile and have 235 rwKw, Ice, ice baby cant touch this. These utes fly