HM Headers

[monaro2003]

Hi all,

I am about to put a set of HM Headers 121SS on a 2003 CV8 series 3. Has anyone had any dealings with them. They are stainless, short 4 into 1 with a 2.5 inch outlet.

Does any body know how good they are or not. I do know that HM usually has good products.

Opinions requested

[LuisS]

You'll love them - we fit them regularly with great results

[gavlotic]

I just had HM123SS and ballistic cats installed recently. They're the long tube 4 into 1. A bit big for my current setup. But Im planning further mods later. Sound bloody nice though.

-Gav

[Peter B - CV8]

Pretty sure that these are the same as the Sureflow 4-1 shorties that I have. Are you getting some hi flow cats as well ???? Nothing wrong with the HM product - they have been around for years & have good runs on the board.

[Party Pete]

I had the 121SS on the Monaro for a while. They produced power fine I didn't find they gave me the sound I was looking for and after much discussion with Mark at Exhaust Technology I ended up going with Pacemaker long 4-1.

[monaro2003]

I am also putting high flow 200 cell stainless magna flow cats. This will complement 2.5 inch x force system.

[Party Pete]

I had the headers with the matching HM high flow cats and cat pipes. I was using a Remus cat back system. It worked fine but I wanted a more traditional V8 "beat" which the short headers didn't provide. Hence I ended up doing everything again. The sound I was looking for only came together with the long headers. That was my experience for what it is worth.

[monaro2003]

Thanks for that advice. Will try these for now as if I have them. If I I go through the same as you then I will change them but still be able to use existing items. If anything that is what I have thought of initially.

[LuisS]

[VZ_V8]

I have these on my ute, they made reasonably good power in my ute. 252rwkw before I got the Ballistic Racing 100CPSI cats installed. Were fitted before I bought it.

[Party Pete]

Absolutely. As I said they do work well enough and they might hit the sweet spot you are looking for with your set up. I certainly won't knock them for the quality of their build and the power characteristics.

[monaro2003]

They look awsome on the car. Will let you know how the CV8 goes. Car is booked for the job to be done this upcoming Saturday.

[monaro2003]

Hi guys

I have had the car running for the past week.Running wise very impressed. The mid range is great. I am how ever disappointed with he level of the sound. It could be a little louder. The exhaust guy reckons it is the back muffler. I need to put a set up that is similar to 2 single resonators. Will see what I will do. I did drive it from the Barossa to the Adelaide hills, and I must admit when running she is not that quiet. I will most probably do what the exhaust guy reckons. Over all at this point very pleased with added performance...

[Shilberite]

About to get a set of 4-1's installed on my vy ss ute. I already have a 2.5inch xforce cat back, then later in the week im getting a vcm otr and a tune done.

[whitels1ss]

About to get a set of 4-1's installed on my vy ss ute. I already have a 2.5inch xforce cat back, then later in the week im getting a vcm otr and a tune done.

You will love it mate!