[fullthrottle]

This was just recently sent to me by another ford forum member.


HPX have now got a bolt on true twin system for the ba xr8s.
This is their claim "This sports system will out perform any similar product below 5000RPM"

They have also kept the pipes 2 1/4 as they say the XR8s are very back pressure sensitive.

Has anyone tried this?

I don't like the fact how it is still within legal limits....to me that is just too soft. But I guess they have to do it if they are to mass produce it.

Here is the PDF.

http://members.optusnet.com.au/fullthrottle/BAV8.pdf

I had to upload it onto my site as I dunno how to upload files here. Please let us know if you have one of these systems on your beast!

 

[rod c]

fullthrottle, I had a email from HPX today saying they are out of stock at the moment and are starting production again today. They have roughly sold 40 systems. So there mighten be any FF members that have tried them yet.

 

[fullthrottle]

So did I. They are adamant that 2.5 inch is too big for the XR8s.
THeir system keeps the orignal Y piece (which is 2.5inch)...same as the herrod setup.
They run a dual 2 1/4 the rest of the way. Herrod's is dual 2.5 going into a single 3". I have no doubt both these setups have been designed to maintain back pressure.

As you probably know I have tried a dozen setups. Previously they have all been barky. However as of yesterday I found a muffler that is giving me the deep and boomy sound I was after. The current setup is a 2 1/2 inch running to a front twin in twin out muffler. Then 2 1/4 the rest of the way going into a smaller resonator.

Now that I have the deep and boomy sound, I am missing the v8 pulse!! You can only hear the pulse on idle or if you floor it. The rest of the time it runs like a turbo 6. Creates a very similar sound to the herrod setup except louder.
What I want to do is get rid of the merge pipe at the front and have 2 seperate pipes. This SHOULD give more pulse. But I'm not sure how this will affect performance (if at all). Perhaps someone with some knowledge on balance pipes can enlighten us?

 

[Fordy]

I always thought balance pipes were necesary.

Are you runing extractors??

 

[fullthrottle]

Nope.
I rang a few places and they all tell me that balance pipes are only necessary for very high powered engine where the pulse needs to be balanced. It can sometimes produce more torque but you're not looking at big differences here. I'm gonna bite the bullet and try the split system. Will let you know if I feel any difference. (it will certainly sound better).

PS. The HPX system seems to be selling like hot cakes...rang two places and they have been sold out! Waiting for more.... hmmmm

 

[Fordy]

What are these systems worth??

 

[fullthrottle]

im getting mixed messages in terms of price.
hpx themselves tell me 1200 retail. I rang a retail (won't say who) and they said 1100 fitted. Not bad for a dual full stainless steel system.

 

[rod c]

Do the original mufflers that are 2 in 2 out keep the exhaust gases from both pipes from mixing or is it 1 big muffler?

 

[rod c]

I was told by email from HPX $1273.50.

 

[Fordy]

Whats a Herrod cat back system worth??

To see a comparison.

 

[rod c]

Roughly $1400.

 

[fullthrottle]

Herrod is $1300. Full stainless steel also.
I doubt there would be much difference in power between the two of them. Maybe slightly different torque characteristics..one is dual 2 1/4 all the way, the other is a dual 2 1/2 to a 3" then out to a dual 2 1/2".

Rod. The original mufflers are seperated pipes. They don't merge.
The front muffler is only 2".

 

[Con]

fullthrottle what brand was the muffler that that gave you the deep boomy sound. if you dont mind sharing that info please.
Cheers,
Con

 

[philstoj]

these systems look surprisingly like my old system.....(the ute one)
dont this company make the zorsts for ford?
it looks exactly like the standard system i took off my au2 xr8 ute....

 

[fullthrottle]

philstoj. I asked them (HPX) if they could describe what it sounds like. The answer was "a bit like the AU XR8s". ) I'd have to hear it to believe it as the windsor v8s with an exhaust sound really good! I asked them to gimme a buzz when they do the next xr8 ute. So will have to wait and see.

Con... I would tell you if i knew. It is a single muffler with twin in twin out. It is quite heavy and feels very solid. Inside the chambers are split i.e. it doesn't merge into a single pipe. I believe it came off a skyline gtr (i didnt know skylines came with twin systems!). The pipes inside are 2.5inch The entry and exit are 2 1/4 inch. Thats the best I can describe it. I'll ask the people what type of muffler it is and will let u know... probably over the weekend.

I only pray that splitting the front section into two seperate pipes will gimme the v8 pulse I'm after and won't loose any torque.

It has been a very long journey for me. Altogether tried about 14 different setups. The zorst joint I went to has been extremely patient with me lol. They were willing to let me try as many system as I like until I got the sound I was after for my intial investment. (I think they regret it lol)

 

[fullthrottle]

well .... had the front section demerged ( made into two seperate pipes). Surprising result. Pulse still not as evident! Sounds good when idling or free reving but no pulse on light to medium throttle. I suspect the "deep and boomy" front muffler has killed the pulse. Good thing is that it doesn't seem to have effected the torque characteristics on the bummometre. I've decided im gonna keep this current one...still not exactly how I like it...but it is one of the better setups out of the 15 odd that I've tried /

Still keen to hear the HPX one.

 

[rod c]

philstoj. I asked them (HPX) if they could describe what it sounds like. The answer was "a bit like the AU XR8s". ) I'd have to hear it to believe it as the windsor v8s with an exhaust sound really good!

As you say fullthrottle with a exhaust because my AU xr8 sounded worse then my BA!!

 

[XRFPV8]

Herrod is $1300. Full stainless steel thats fitted.. is the hpx for Roughly $1400 fitted ???

 

[rod c]

Sorry, Herrods price was a quote I got up here fitted and freight ect....... HPX quoted me $1273.50, yeh, I would say roughly $1400 fitted.

 

[FANTM1]

To "rod c" I have stripped the orig rear muffler. The internals are, 1st section is made up of two perforated 2" pipes sharing a common perforated oval chamber,then a wrap of sound deadener, the pipes then go into a second chamber stepping back up to 2&1/4" inch pipes which seem to have some tuning ports hanging off of them. I have modified my rear by packing the first section with f/glass and welding the two ports closed. I then cut off the rear pipes and removed the perforated inserts and deadenig material and welded them back on. This gives a much better idle note from the rear(deeper and slightly louder) and under heavy acceleration sounds like it really means business. But it still doesn't have that meaty sound at lesser throttle.

The HPX system may be the answer but I'd like to hear one.

One of the guys in our club has a 3" single system using a Redback chambered muffler. that sounded pretty meaty. It was on an auto XR8. made plenty of beefy noise, maybe a rear res. would work to reduce the level, if required.