Exhausting times.... - Page 2

**Stav** · 06-08-2008, 05:02 PM

Quote:

Originally Posted by Sox

I'll PM you the exhaust dude in Blacktown if you like, he has made all my systems for the last 20 years.
Remember my XH had 175rwkw and ran 14.4 with no traction. It had JMM race headers, with a press bent 2.5" system made by the guy in Blacktown. I believe the main muffler was custom made and it also had a resonator and a hot dog because I wanted it very quiet.
My current AU has a Mercury muffler fitted by him I think.

I have known yor exhaust bloke since was 7 mate. He is a very nice bloke. Used to be a customer at my dads corner store..

I also 100% agree with you that that the primary/secondary lengths and diameters have a huge effect on power delivery.

Sox · 06-08-2008, 05:21 PM

Quote:

Originally Posted by Stav

I have known yor exhaust bloke since was 7 mate. He is a very nice bloke. Used to be a customer at my dads corner store..

I hope we're both on the same page here... Bruce, right.

**Stav** · 06-08-2008, 05:23 PM

Yes. He is up at Sunnyholt Road..Perhaps not 7 but definately from my teenage days

Sox · 06-08-2008, 05:35 PM

Quote:

Originally Posted by Stav

Yes. He is up at Sunnyholt Road..Perhaps not 7 but definately from my teenage days

Yer, nice bloke, been in the game a long time and knows his stuff.
Go and talk to him about exhaust science.

**Stav** · 06-08-2008, 05:37 PM

What was your average mph and best mph with our headers? Ive averaged 96.7mph and a best once of 97....
Heck what is the best mph for our headers from anyone?

edit..Ive got to stop the guessing and actually test what I have first..

Sox · 06-08-2008, 05:45 PM

Quote:

Originally Posted by Stav

What was your average mph and best mph with our headers? Ive averaged 96.7mph and a best once of 97....
Heck what is the best mph for our headers from anyone?

My results were line ball with yours. Best was a frag under 97, with consistant 96's.

My runs were done with a temp of just under 30deg.

As I said in a previous post, I had no traction, the tyres were probably 2 years old. My ute also had very stiff springs with Bilstien shocks which provided no squat whatsoever. It launched like a pig with best 60 times of more than 2.2secs.

With good traction and cooler weather, my ute would have run like Brendans ute, 14.0 and 99mph.

DEV5 kit, standard XR ECU, press bent 2.5" system, 3.45 diff, 5spd.

The Monty · 06-08-2008, 06:00 PM

Quote:

Originally Posted by Sox

Because they are race engines which are constantly revving high, likely always between 4000-6000rpm.
Road cars need to work off a different set of rules, such as low rpm power, noise control, etc.

Thats fair enough, but if we are at the strip, we arent really spending much time below 4000rpm, so it could be optimal for racing, but not street.

Sox · 06-08-2008, 06:07 PM

Quote:

Originally Posted by The Monty

Thats fair enough, but if we are at the strip, we arent really spending much time below 4000rpm, so it could be optimal for racing, but not street.

Very likely.

**Stav** · 06-08-2008, 06:13 PM

Quote:

Originally Posted by Sox

My results were line ball with yours. Best was a frag under 97, with consistant 96's.

My runs were done with a temp of just under 30deg.

As I said in a previous post, I had no traction, the tyres were probably 2 years old. My ute also had very stiff springs with Bilstien shocks which provided no squat whatsoever. It launched like a pig with best 60 times of more than 2.2secs.

With good traction and cooler weather, my ute would have run like Brendans ute, 14.0 and 99mph.

DEV5 kit, standard XR ECU, press bent 2.5" system, 3.45 diff, 5spd.

I ran 97 mph in 28 degrees with the 14.301. In winter 14.241 at 96.7 mph in 14 degrees

Sox · 06-08-2008, 06:18 PM

Quote:

Originally Posted by Stav

I ran 97 mph in 28 degrees with the 14.301. In winter 14.241 at 96.7 mph in 14 degrees

Was everything identical though?
I know you've messed with so many things so often I doubt you'd even remember.

:
Most cars pick up a couple tenths and few mph. Some even more, particularly those which are too rich.
My A/F ratios were spot on, so their wouldn't have been a lot.

**Stav** · 06-08-2008, 06:46 PM

I did use different fuel..hehhe. Nar I think the culprit is a tiny oil leak in the number 1 spark plug thread.

**Stav** · 06-08-2008, 08:44 PM

This is a top ten list for the au 4.0 six powered au's.The top 3 mph cars are

SIKSIX 99.58 Manual
Geza 99.23 ?
Hamo 97.6 Auto
Some may be manuals which of course have an extra 10 rwkws over autos...but what xorst did they run?

SIKSIX · 06-08-2008, 08:49 PM

Quote:

Originally Posted by Stav

SikSix..my 3 inch was done by simply having a 3 inch flange welded onto the headers.Bolted straight on.What have you been up to man? When are you running again? Help shuffle the top ten

School and work, I have raced again since the 14.4 but with no luck, 60 ft's were ok (2.1-2.0) but the bit the clutch cable hooks onto the fork slowly bent over the night left me granny, granny shifting (to save my g/box) but still managed 14.6@95-ish mph so theres more in it. At least i like to think so

: . Then it gave up completely snapping off that night and so did i for a while but damn this forum is getting me back into it!!

On topic, how much gain is there to be had in upgrading the cat? cause i am still running my std. cat and what is the life on one of them things. How can i tell if it needs replaceing?

Just seen the post, i have pacie comps i think 4480's, std cat, red back 2.5" (recently no resonator)

**Stav** · 06-08-2008, 08:58 PM

In all honesty...I dont know how much gain there is in the cat.I can make an educated guess though...I would recommend a hi flow metal cat to get an increase but be prepared for another tune as the car will feel slower until you do.Once tuned you will be a very happy camper. I will take a stab in the dark that you should see another tenth off your times

edit to your edit

95 mph is good for a 14.4 and maybe a 14.3. We can only gauge the effectiveness of the paccies once you have a better cat ...