I'm been running the RPW headers from Australia and wondering if anybody else had headers and what piping size and exhaust you might be using?

I run the RPW's. I am using 2 1/2 CAT input and 2 1/2 CAT output. Using the Magnaflow 94006 - the requirement is a Magnaflow 53004 2" universal. But I have been using this model for years so everytime it needs to be replaced they just get the same one <img src="/forums/images/graemlins/wink.gif" alt="" />! I use a Magnaflow Muffler Flowthrough 2 1/2" and 2 1/2 inch pipe all the way back.

Do you have a picture of how the headers look both off and on the vehicle? Also, any noticeable difference in performance?

I can take pictures of it on. I have no pictures of it off.
Performance wise. I got 3 - 4 mpg better ( which is what I am after ),
much better mid range power , but this is in conjunction with a set of RPW stage 1 cams
and a ECU with JET reprogramming. The seat of the pants DYNO says the headers were worth
about 20 power and the cams and ECU were 70% of the total upgrade.
( Headers 1st , then CAM, ECU, and intake / exhaust port job on the heads).
The cams were mid rage enhancement.
Though there are DYNO's near me - none large enough to hold the truck.
If there were I would do a real check and tune

BS, Sorry for going off topic but I'd like to hear about your ECU getting Jet Chipped.

Me too.

John B.

Back in the day (04-05?) I posted pics of the headers before and after install, but they don't seem to show up on my post history...we discussed the 3.0 having the kahuna's to merit/benifit from a dual exhaust system....the concensus was it didn't!

Brian,
Thanks for the info....I assume your running the headers into a single exhaust? What are you using to tie it into a
2 to 1 system?
BJ

So the RPW headers are 2 to 1 from RPW. You can order manual or automatic versions.
The difference is the crossover pipe from the drivers side to the passangers side to clear the automatic trans.
This is my second set of RPW headers the first cracked and needed to be replaced after 5 years
.
The first pair were automatic and fit like a glove , the 2nd set was by mistake manual
and did not fit without modification which I did cause I didn't want to wait for a ne xover pipe.

Now the JET chip ... You need to send your ECU to them.
They reprogram it and send it back for $399.
I pass smog CA ( except for visual inspection ) with flying collors. The performance is much better
and I got better MPG out of it. It was worth ito me. Steep price though - I wrestled with the
cost factor for a while but could not resist. BTW I have a spare stock ECU so it was not a biggie.

Brian,

Is your Magnaflow Flowthru muffler a 30121?

As my 89 doesn't need a CAT up here in the "LIVE FREE OR DIE" state of New Hampshire I was thinking of running straight 2 1/2" pipe off each header into a dual inlet Magnaflow with a 3" outlet.

Right now I'm running 2 into 1 from the headers, all 2" piping and have not ever been satisfied with the performance or sound.

Just saw RPW says 2 1/2 is the minimum piping, so there's part of my problem!
What do you guys think....is it worth the trouble?

I've always liked true duals with a balance pipe connecting the two sides. Since you don't need cats (well, some of you), it would be cheaper by far.

I'd use 2 1/2", mufflers right at the header reducer flange, then crossover/balance tube, true dual all the way back, and maybe small resonators just before the exits.

At least in AZ, you have to do it right, because the thing won't ever rust out. In other parts of the country, it's only a matter of time before you just have to do it again, so what the heck, just try it...

John B.